TW202211943A - Respiratory gas delivery and sampling system - Google Patents

Abstract

There is provided a respiratory gas delivery and sampling system, a gas sampling system, a gas sampling interface and a gas sampling tip that may be used to sample exhaled and/or expired gases from a patient, particularly from a patient who is apnoeic and/or who is receiving high flow respiratory therapy. The gas sampling system comprises a respiratory gas monitor in fluid communication with the gas sampling interface, which comprises the gas sampling tip of the invention. The gas sampling interface comprises a gas sampling conduit and the gas sampling tip is located at a free end of the conduit. The gas sampling interface may be configured to allow the gas sampling tip to be selectively positioned at or in the mouth or a nare of the patient's nose.

Description

Breathing gas delivery and sampling system

The present application relates generally to respiratory gas therapy. More specifically, the present application relates to an interface for capturing exhaled and/or exhaled gas (eg, CO ₂ ) near a patient's nose or mouth while supplying breathing gas to the patient via a breathing apparatus . In use, the interface includes or is typically fluidly connected to a gas sampling conduit fluidly connected to a breathing gas monitor. The interface can be particularly useful when measuring the exhaled and/or exhaled gas of a patient receiving high flows of breathing gas.

In a medical setting, it is common practice to monitor patient exhaled and/or exhaled gas concentrations using a gas sampling system that includes a respiratory gas monitor connected to a gas sampling interface that includes a gas sampling tube to convey the Suffered exhaled and/or exhaled gas to a respiratory gas monitor. Respiratory gas monitors are well known in the art and can range from more comprehensive monitors capable of monitoring many different types of gases (eg nitrogen, O ₂ , CO ₂ , anesthetic gases, etc.) to monitoring only a single type of gas more specialized monitors. An example of a more specialized respiratory gas monitor is a capnography/capnograph, which works by inhaling the patient's exhaled and/or exhaled gas into a gas sampling interface connected to a capnography/capnograph. Monitor carbon dioxide. Anesthesia machines may also provide breathing gas monitors. The breathing gas monitor may be fully or partially integrated into the anesthesia machine, or may be independent of the anesthesia machine. Respiratory gas monitors provide a small amount of suction to draw gas into the sampling catheter.

The respiratory gas monitor receives exhaled and/or exhaled gas via the sampling conduit of the gas sampling interface. For example, the inlet of the sampling catheter may be positioned near the patient's nose or mouth such that the sampling catheter captures passing exhaled and/or exhaled gas that then enters the catheter through the inlet. In some cases, the inlet may be fluidly connected to or form part of a breathing apparatus, such as a mask or catheter. In some cases, the sampling catheter is independent of the patient interface, and the terminal end of the sampling catheter can be held or affixed in place on the patient's face.

Although gas sampling is commonly used to anesthetize patients, known gas sampling interfaces, gas sampling conduits, and gas sampling procedures are fraught with difficulties.

For example, the process of attaching a sampling catheter to a patient's face requires some preparation time and skill from some anesthesiologists, anesthesiologists, nurses, or other medical personnel. The sampling catheter must also be properly positioned so that the catheter/tube can be placed so that it can reliably capture exhaled and/or exhaled gas.

The gas sampling interface or sampling conduit can also be removed if the patient moves their head, or if an instrument is used to approach, or have to maneuver around the sampling interface or conduit.

Some gas sampling interfaces may also interfere with instruments or equipment such as mouthpieces, endoscopes or laryngoscopes. Additionally, if a portion of the sampling catheter is located within the patient's mouth, the tip of the sampling catheter may become blocked with saliva or blood, or may be drawn into the interior of the patient's cheek or onto the patient's tongue.

The current approach does not allow simple repositioning of the sampling interface when needed. For example, reliable _CO sampling can be difficult when it is unclear before the procedure whether the patient is breathing primarily through the nose or mouth. For example, if a sampling catheter was affixed in place at the patient's nose, and it was subsequently apparent that the patient was breathing primarily from the mouth, it would be necessary to remove the catheter and then affix the catheter to the appropriate location at the patient's mouth Location. Repositioning the sampling catheter in this manner requires repeating the sampling catheter attachment procedure, which is time consuming.

Accordingly, it would be desirable to provide a sampling interface that facilitates engagement of a sampling catheter with a patient such that engagement is rapid and catheter placement reliably captures _CO2 in exhaled and/or exhaled breaths.

Gas sampling is particularly difficult when a patient is apnea (due to a very low amount of air exhaled or exhaled from the lungs of an apnea patient). Exhaled _CO2 cannot be accurately detected in the nose or mouth because there is no patient ventilation to effectively expel gas away from the lungs, and any gas exiting the nose or mouth is significantly thin. may simply spread from the airways of apnea patients). It is possible to sample the exhaust gas from anywhere in the trachea where the exhaust gas is thinner (ie, from the back of the throat to the tracheal carina). However, sampling the back of the throat can create difficulties during procedures that require access to the patient's airway, such as during oral procedures where the sampling interface may interfere with the surgeon's tools. It is also difficult (and sometimes impossible) to intubate patients undergoing oral surgery. For this reason, high-flow breathing therapy is sometimes used to provide breathing gas to patients undergoing oral surgery or surgery on sites accessed through the mouth, but high-flow therapy can also be used for many other medical procedures. High-flow therapy refers to the supply of breath to an adult patient at a high flow (usually between about 15 L/min and about 150 L/min, preferably between about 30 L/min and about 120 L/min) via a breathing apparatus gas. However, the flow defined as high flow can vary from patient to patient. For example, in high-flow therapy of newborn infants, breathing gas is typically supplied at a flow rate of about 2 L/min/kg. Low-flow catheters typically cannot deliver breathing gas at flow rates higher than 15 L/min.

The nature of high-flow therapy results in significant dilution of the patient's exhaled air, making accurate measurement of _CO2 and other exhaled gases difficult.

More specifically, the anatomical dead space is the total volume of the patient's airway from the nose and mouth to the terminal bronchioles. During normal exhalation, this dead space is filled with _CO2 -rich gas from the lungs. At the transition point from expiration to inspiration, the _CO2 -rich gas remaining in the dead space is re-inhaled into the lungs as part of inspiration. When _CO2 monitoring is used in this state (ie, the patient is breathing normally without assistance), the _CO2 -rich gas system that fills the dead space during expiration is the gas measured by the gas sampling system. Due to the uniform gas distribution, the CO ₂ sampling interface can be used for nasal or oral sampling for sampling measurements roughly equivalent to CO ₂ concentrations in the lungs, allowing for extrapolation of the measurements. However, monitoring CO ₂ or other expiratory and/or exhaled gases while providing high flow therapy (supplying a patient with breathing gas at high flow via a breathing apparatus) is difficult. This is due to the irrigation mechanism provided by high-flow therapy, which alters the flow pattern within the anatomical dead space, resulting in an uneven distribution of exhaled gas. The _CO2 -rich airflow from the lungs is removed or "flushed away" from the dead space by fresh gas from the breathing apparatus and also (to a small extent) by the psychogenic pulse. As a result, the high flow treatment creates a swirling pattern of gas motion with a recirculation character, resulting in less _CO2 being reabsorbed. When sampling a non-uniform gas distribution from the nose and/or mouth, ineffective quantitative measurements are made by standard respiratory gas monitors in gas sampling systems. Compensation algorithms can be implemented to help interpret incorrect measurements, and if enough _CO2 is sampled, qualitative interpretation of the gas sample is still possible.

US Patent No. 7,337,780 discloses a combined gas delivery and gas sampling interface. The interface includes a nasal cannula with a mouth channel, wherein gas is delivered through one of the nasal cannulae of the catheter, and the gas is sampled through both the other cannula and the mouth channel. The mouth passage includes a wire spine that bends the mouth passage to a desired position to sample exhaled air from the patient's mouth. However, catheters are not suitable for providing high flow therapy, delivering therapy through both nostrils of the patient's nose, or allowing selective gas sampling from the nose or mouth.

Accordingly, it would be useful to provide a gas sampling interface that can be used to selectively sample exhaled and/or exhaled gas from the mouth or nose, even when supplying gas to apnea patients under high flow therapy.

After use of the sampling catheter, in order to prevent contamination, the sampling catheter typically needs to be disposed of, replaced or sanitized before the next patient.

Thus, it is also advantageous to facilitate the disposal or sanitation of the sampling catheter or related elements.

According to a first aspect, there is provided a gas sampling interface comprising: a conduit having a body having a hook portion for engaging a portion of a patient's face, the body defining a cavity having a cavity for receiving a patient's breath An inlet for air and/or exhaled air and an outlet for delivering exhaled and/or exhaled air to a gas measuring device.

In one form, the hook portion is adapted to engage the patient's face at or near the orifice of the patient's face. Preferably, the hook portion is adapted to engage with the patient's mouth or a portion of the patient's mouth. The hook portion may be adapted to engage the patient's nose or a portion of the patient's nose. Preferably, the shape of the hook portion is adjustable. In one form, the hook portion includes a substantially convex portion. Preferably, the body further comprises a substantially concave portion leading to a substantially convex hook portion leading to another substantially concave portion.

Preferably, the interface is disposable.

In one form, the catheter is a dual catheter lumen. In one form, the gas sampling interface further includes a length of malleable wire occupying one of the lumens.

In another form, the catheter is a single lumen catheter.

Preferably, the conduit is or comprises a polymeric material.

The catheter can be connected to the sampling tube via a luer fitting.

Preferably, the inlet has a mouth with a larger cross-sectional area than the conduit or lumen.

In one form, the catheter has heads of alternating or varying depths when viewed in cross-section.

Optionally, the conduit includes a plurality of gas receiving holes or openings around the periphery of the head and/or along the distance of the conduit from the tip. Preferably, the catheter includes one or more non-circular openings around the periphery of the head and/or along the distance of the catheter from the tip.

Preferably, the head of the interface includes a filter or head structure adapted to substantially inhibit the ingress of liquid. The head structure may comprise an absorbent porous sponge or foam at least partially surrounding the tip of the interface.

Preferably, the head structure includes a shroud, cage, roller or spacer surrounding the interface head. In one form, the cover includes a substantially cylindrical element. In another form, the shroud includes an elongated element having a substantially C-shaped cross-section. In yet another form, the cover includes an elongated element having a substantially square cross-section. Optionally, the cover has one or more openings or cutouts. For example, the cover may comprise toothed elements. Alternatively, the cover may include curved elements. In one form, the cover includes a substantially V-shaped element. In another form, the cover includes a planar element.

According to a second aspect, a gas sampling interface is provided, the gas sampling interface including a hook for engaging a portion of a patient's face and for securing a gas sampling conduit relative to the hook such that the inlet receives the patient's exhaled breath or attachment means for exhaled breath.

Preferably, the hook is rigid. Alternatively, the hook is flexible. In one form, the position of the gas sampling conduit relative to the hook is adjustable.

Preferably, the attachment member is removably attached to the gas sampling conduit. In one form, the attachment member consists of or includes a channel. In another form, the attachment member consists of or includes a clip or a pair of clips. In one form, the attachment member consists of or contains an elastomeric material. The attachment member may optionally be integrally formed with the hook. Alternatively, the attachment member is a separate element from the hook.

According to a third aspect, there is provided a gas sampling interface comprising: a nasal cannula having a manifold and at least one nasal cannula or outlet extending from the manifold to be received within a patient's in the nostril; and an attachment member that secures the gas sampling catheter relative to the nasal cannula such that the inlet port receives the patient's exhaled or exhaled gas.

Preferably, the attachment member is removably attached to the gas sampling conduit. In one form, the attachment member consists of or includes a clip or a pair of clips. In another form, the attachment member consists of or includes a strap or sleeve. Optionally, the attachment member consists of or includes an elastomeric material. In one form, the attachment member is integral with the manifold and/or at least one nasal cannula or outlet. In another form, the attachment member is a separate element from the manifold and/or at least one nasal cannula or outlet. Preferably, the position of the gas sampling conduit is adjustable relative to the attachment member.

According to a fourth aspect, there is provided an assembly comprising a gas sampling catheter and an attachment member for securing the gas sampling catheter to a nasal cannula, wherein the attachment member is attachable to the nasal cannula, the attachment member comprising at least two An offset clip attachable to the gas sampling conduit to allow the gas sampling conduit to follow a tortuous path when connected.

Preferably, the attachment member is removably attached to the gas sampling conduit. In one form, each clip includes a tube receiving area within which a portion of the gas sampling conduit can be retained.

In one form, the attachment member includes a sleeve including a body and a pair of spaced arms projecting from the body, wherein the sleeve further includes an interior region between the arms and an opening to the interior region, wherein the opening is formed along the length of the cannula and is defined by a side edge of the arm, and wherein the interior region is configured to receive a portion of the breathing apparatus. Optionally, the body of the attachment member includes a sleeve including an inner region and an opening to the inner region, wherein the opening is formed along the length of the sleeve and is defined by a side edge of the sleeve, and wherein the inner region is configured to receive a portion of a breathing apparatus. Preferably, the inner region includes a substantially arcuate inner surface. For example, the sleeve may comprise a substantially C-shaped cross-section. In another form, the sleeve includes a substantially U-shaped cross-section. Optionally, the substantially arcuate inner surface is formed by a plurality of substantially flat surfaces connected in series to form the substantially arcuate shape. In this form, the sleeve may comprise a substantially C-shaped cross-section. Alternatively, the sleeve may comprise a substantially U-shaped cross-section. Preferably, the sleeve is formed of a substantially flexible elastic material. For example, the sleeve may comprise a polymeric material. Preferably, the inner region of the cannula is substantially curved, and the inner region of the cannula is dimensioned to receive a portion of the gas delivery tube of the nasal cannula, and the width of the opening between the side edges is smaller than that by the attachment. The diameter of the portion of the gas delivery tube held by the member. In one form, the arms of the sleeve are offset from each other. Each clip may form a hook comprising a curved arm extending from the body and terminating at a distal end, wherein the arm may include an inner surface forming a substantially concave receiving area. Preferably, the diameter of the substantially concave receiving area is at least as large as the diameter of the gas sampling lumen. In one form, the distance between the distal portion of the hook and the body is less than the diameter of the gas sampling catheter.

Preferably, the attachment member is configured to attach to a side arm of a catheter such as a nasal cannula. Optionally, the size or shape of the concave receiving area of the clip matches the shape of the catheter side arms. In one form, the concave receiving area of the clip includes a plurality of flat surfaces shaped to receive the side arms of the catheter.

According to a fifth aspect, there is provided a gas sampling head removably connected to an inlet of a gas sampling conduit, wherein the sampling head includes a body including a substantially hollow interior region, the substantially hollow The interior region is configured to be in fluid communication with the inlet of the gas sampling conduit when connected to the gas sampling conduit, and wherein the body also includes a distal portion, the distal portion including a distal surface and an outer surface, wherein the gas sampling tip Further included is at least one gas-receiving aperture for receiving patient exhaled or exhaled gas, and wherein the gas-receiving aperture is in fluid communication with the substantially hollow interior region of the body.

Preferably, at least one gas receiving hole is formed in both the distal surface and the outer circumferential side surface such that the gas receiving hole extends from the distal surface and along the outer side surface. In one form, the at least one gas receiving hole forms an elongated opening in the distal portion of the gas sampling head. The distal end of the gas sampling head can be bent outwardly. For example, the distal portion of the gas sampling head may be substantially spherical.

Preferably, the gas sampling head includes three gas receiving holes evenly spaced around the distal end of the sampling head. Preferably, the distal end of the gas receiving hole(s) is narrower than the opposite end of the gas receiving hole(s).

In one form, the gas sampling head has a substantially cylindrical shape and forms a substantially circumferential outer surface. Preferably, each portion of the body located between the gas receiving holes forms a groove, wherein the grooves are substantially evenly spaced around the circumference of the distal portion of the gas sampling head.

According to a sixth aspect, a gas sampling interface is provided, the gas sampling interface comprising: a gas sampling conduit, the gas sampling conduit comprising an inlet for receiving exhaled or exhaled gas of a patient and an outlet connected to a respiratory gas monitor; and a removable sampling head at the inlet of the conduit, wherein the sampling head includes a body including a substantially hollow interior region configured to interact with the gas sampling conduit when connected to the gas sampling conduit The inlet of the gas sampling catheter is in fluid communication, and wherein the body further includes a distal portion, the distal portion including a distal surface and an outer surface, wherein the gas sampling head further includes at least one gas receiving aperture to receive patient exhalation or exhalation A gas, and wherein the gas receiving aperture is in fluid communication with the substantially hollow interior region of the body.

Preferably, at least one gas receiving hole is formed in both the distal surface and the outer side surface such that the gas receiving hole extends from the distal surface and along the side surface. The gas receiving hole may form an elongated opening in the distal portion of the gas sampling head. In one form, the distal end of the gas sampling tip is curved outward. For example, the distal portion of the gas sampling head may be substantially spherical.

Preferably, the gas sampling head includes three gas receiving holes evenly spaced around the distal end of the sampling head. The distal end of the gas receiving hole(s) may be narrower than the opposite end of the gas receiving hole(s). In one form, the gas sampling head has a substantially cylindrical shape. The gas sampling head may include three gas receiving holes evenly spaced around the distal end of the sampling head. Preferably, each portion of the body located between the gas receiving holes forms a groove, wherein the grooves are substantially evenly spaced around the circumference of the distal portion of the gas sampling head.

The gas sampling conduit can include a first lumen through which gas can flow and a second lumen, wherein a flexible elastic structural support member is located in the second lumen to allow the gas sampling conduit to bend into a desired shape and maintain substantially the desired shape. Alternatively, the gas sampling conduit includes a tube wall in which the flexible resilient structural member is located. The gas sampling conduit may be coextruded with the structural member to enclose the structural member within the wall of the conduit. The structural support members may include metal filaments. For example, the structural support members may include wires. The wires may be formed at least in part from stainless steel, aluminum, or nickel titanium.

According to a seventh aspect, a gas sampling interface is provided that includes a gas sampling conduit including a gas inlet, a gas outlet, and a malleable spine that allows the gas sampling tube to bend into a desired shape; wherein the gas sampling The interface further includes a removable gas sampling head including at least one gas receiving aperture in fluid communication with the gas inlet of the gas sampling conduit.

Preferably, the malleable spine is semi-rigid to allow the gas sampling catheter to bend into a desired shape and substantially maintain that shape. In one form, the malleable spine includes a wire. The wires may be formed at least in part from stainless steel, aluminum, or nickel titanium.

Preferably, the gas sampling head includes a body having a substantially circular cross-section, and further includes at least three gas receiving holes formed in the body, wherein each gas receiving hole extends from the distal end of the body and along the sides of the body , and wherein the gas receiving holes are evenly spaced circumferentially around the body to form grooves between adjacent gas receiving holes.

According to an eighth aspect, the present invention provides a gas sampling head for connection to an inlet of a gas sampling conduit, wherein the sampling head includes a body including a substantially hollow interior region configured being in fluid communication with the inlet of the gas sampling conduit when connected to the gas sampling conduit, and wherein the body also includes a distal portion having a distal wall and an outer surface, wherein the gas sampling head further includes a gas receiving hole connected to to the interior region and configured to receive patient exhaled or exhaled gas, and wherein the gas receiving aperture extends substantially around the entire outer perimeter of the outer surface.

Preferably, the gas sampling head end wall is supported by a centrally disposed support member connected to at least one inner wall of the body, and wherein the gas receiving hole extends around the entire outer periphery of the outer surface. The body of the sampling head may be substantially cylindrical, and the gas receiving hole forms an annular hole around the outside surface of the body. In one form, the body of the sampling head is substantially cylindrical, and the gas receiving apertures form helical apertures around the outside surface of the body.

According to a ninth aspect, the present invention provides a gas sampling head including a body having a substantially hollow interior region, wherein the body includes one or more sidewalls forming an outer surface of the body, configured to communicate with a gas The sampling conduit connects a proximal end such that the hollow interior region is in fluid communication with the gas sampling conduit, a distal end defined by the end wall, and wherein the body further includes a gas receiving hole forming an opening to the hollow interior region of the body, wherein the gas receiving holes extend substantially around the entire outer periphery of the outer side surface of the body.

In one form, the end wall is substantially transverse to and offset from the gas receiving aperture. Optionally, the end wall is integrally formed with the body. The cross-section of the wall may be the same as or larger than the cross-section of the gas-receiving hole. In one form, the end walls are longitudinally offset by a distance equal to or greater than the width of the gas receiving aperture. Optionally, the end wall is cantilevered from a portion of the body by a support member, which may comprise a strut, rod, arm or elongated extension. In one form, the body is substantially cylindrical, and the gas receiving apertures form an annular ring around the body. Alternatively, the body is substantially cylindrical, and the gas receiving holes form a helical arrangement around the body.

According to a tenth aspect, the present invention provides a respiratory therapy system for delivering high-flow respiratory therapy to a patient and sampling the patient's exhaled or exhaled gas, wherein the system includes: a breathing apparatus that includes a patient an interface and a breathing gas delivery tube connected to a gas source for delivering high flow breathing gas from the gas source to a patient through the breathing gas delivery tube through the patient interface; and a gas sampling interface, the The gas sampling interface includes a conduit including a first end in fluid communication with a respiratory gas monitor and a second distal end including at least one inlet for receiving expiratory or exhaled breathing gas from a patient, wherein at least a A portion is flexible to allow the portal to be selectively positioned at the patient's mouth or nose. In some forms, the breathing apparatus provides breathing gas to the patient at a flow rate between about 15 and about 150 L/min. Optionally, the breathing apparatus provides breathing gas to the patient at a flow rate between about 30 to about 120 L/min, or about 60 to about 110 L/min, or about 50 to about 150 L/min, or about 60 to about 100 L/min . In some forms, the breathing apparatus provides high flow breathing gas to the patient at a flow rate greater than about 30 L/min, greater than about 40 L/min, greater than about 50 L/min, greater than about 60 L/min, or greater than about 70 L/min. Optionally, the system is configured to deliver breathing gas to the newborn infant patient at a flow rate of about 2 L/min/kg.

In one form, the catheter includes a flexible elastic support structure that allows the distal portion to be manipulated into a desired shape and selectively directed toward the patient's nose or mouth. The flexible elastic support structure may include a wire within the catheter that allows at least a portion of the catheter to bend to form a hook-like shape. Optionally, the wire has a diameter smaller than the inner diameter of the conduit, and wherein a gap is formed between the wire and the inner wall of the conduit to allow gas to flow along the conduit. In one form, the conduit includes a first gas receiving lumen and a second support lumen. In this form, the wire is located in at least a portion of the support lumen. Optionally, the wire is coextruded with the gas sampling conduit. In one form, the guidewire is located in the distal portion of the catheter to allow the distal portion to bend to form a hook-like shape.

In one form, the system also includes an attachment member that attaches the gas sampling interface to the breathing apparatus. Optionally, the attachment member is integral with or attached to the breathing gas delivery tube, and the attachment member comprises: a sleeve at least partially surrounding a portion of the breathing gas delivery tube; wherein the sleeve The barrel includes at least one clip on the outer surface of the sleeve for receiving a portion of the catheter for attaching the catheter to the breathing apparatus. In one form, the sleeve includes a pair of clips that are offset from each other. Each clip can include a hook that includes a tube receiving area within which a portion of the catheter can be positioned to follow a tortuous path. Preferably, the hooks face in opposite directions to each other.

In one form, the gas sampling interface further includes a head at the distal end of the catheter, wherein the head includes a substantially hollow body including at least one gas receiving aperture to receive patient exhaled or exhaled gas, wherein the gas receiving hole is in fluid communication with at least one inlet of the conduit, and wherein the body of the head further includes a distal portion including a distal surface and an outer surface. At least one gas receiving hole may be formed in both the distal surface and the outer circumferential side surface such that the gas receiving hole extends from the distal surface and along the outer side surface. In one form, the at least one gas receiving hole forms an elongated opening in the distal portion of the gas sampling head.

In one form, the body of the head includes a substantially cylindrical shape. Optionally, the distal end of the gas sampling tip is curved outward. Preferably, the distal portion of the gas sampling head is substantially spherical.

In one form, the gas sampling head includes at least three gas receiving holes evenly spaced around the distal end of the sampling head. Optionally, each portion of the body located between the gas receiving holes forms grooves, wherein the grooves are substantially evenly spaced around the circumference of the distal portion of the gas sampling head.

Preferably, the breathing apparatus is a nasal cannula.

Preferably, the patient receiving treatment from the breathing apparatus is apnea.

According to an eleventh aspect, the present invention provides a gas sampling interface for use with a high flow breathing gas delivery system, the gas sampling interface comprising: a conduit including a first end in fluid communication with a breathing gas monitor; a second distal end, the second distal end including at least one inlet for receiving expiratory or exhaled breathing gas from the patient; a gas sampling head located at the distal end of the catheter and including a substantially hollow body , the substantially hollow body includes at least one gas-receiving hole to receive patient exhaled or exhaled gas, wherein the gas-receiving hole is in fluid communication with at least one inlet of the catheter, and wherein the body of the head further includes a distal surface and an outer surface the distal part of the . Preferably, at least one gas receiving hole is formed in both the distal surface and the outer circumferential side surface such that the gas receiving hole extends from the distal surface and along the outer side surface to form an elongated opening in the distal portion of the gas sampling head.

Optionally, the distal portion of the gas sampling head is substantially spherical.

In one form, the gas sampling head includes three gas receiving holes evenly spaced around the distal end of the sampling head. Optionally, each portion of the body located between the gas receiving holes forms grooves, wherein the grooves are substantially evenly spaced around the circumference of the distal portion of the gas sampling head.

In one form, the gas sampling conduit is connected to the gas sampling line of the breathing gas monitor via a luer fitting.

In another form, the gas sampling conduit is connected directly to the inlet of the respiratory gas monitor.

In one form, the gas sampling interface is configured to receive exhaled or exhaled gas from a patient receiving breathing gas from the breathing apparatus at a flow rate between about 15 and about 150 L/min. Optionally, the gas sampling interface is configured to operate at between about 30 and about 120 L/min, or between about 60 and about 110, or between about 50 and about 150 L/min, or between about 60 and about 100 L/min The flow comes from the breathing device receiving the exhaled or exhaled gas from the patient who is receiving breathing gas. In some forms, the gas sampling interface is configured to receive a high flow rate from the breathing apparatus at a flow rate of greater than about 30 L/min, greater than about 40 L/min, greater than about 50 L/min, greater than about 60 L/min, or greater than about 70 L/min Flow Exhaled or exhaled gas of a patient breathing gas.

Optionally, the gas sampling interface is configured to receive the breathing gas of the neonatal infant patient receiving breathing gas from the breathing apparatus at a flow rate of about 2 L/min/kg.

In one form, at least a portion of the catheter is flexible to allow the inlet to be selectively positioned at the patient's mouth or nose.

According to a twelfth aspect, the present invention provides a breathing apparatus comprising: a nasal cannula having at least one nasal cannula for support extending from a manifold and to be received in a user's nostrils or a manifold of outlets; a gas delivery tube in fluid communication with at least one nasal cannula or outlet to supply breathing gas via the at least one nasal cannula or outlet; and an attachment member for connecting the A gas sampling interface is attached to the nasal cannula, wherein the gas sampling interface includes a conduit including a first end in fluid communication with the respiratory gas monitor and a second distal end, the second distal end including at least one for receiving a patient An inlet for the patient's exhaled or exhaled breathing gas, wherein at least a portion of the conduit is flexible to allow the inlet to be selectively positioned at the patient's mouth or nose, and wherein the attachment member is connected to the breathing gas delivery tube or manifold The tube is integral with or attached to the breathing gas delivery tube or manifold, and the attachment member comprises: a sleeve at least partially surrounding a portion of the breathing gas delivery tube or manifold; wherein the sleeve comprises for receiving A portion of the gas sampling conduit to attach the conduit to at least one clip of the breathing apparatus. Optionally, the cannula includes a substantially arcuate inner surface to enclose a portion of the breathing gas delivery tube. The clips may be located on the outer surface of the sleeve. Preferably, the sleeve includes a pair of clips that are offset from each other. Each clip optionally includes a hook that includes a receiving area in which a portion of the catheter can be positioned to follow a tortuous path. Preferably, the hooks face in opposite directions to each other. In one form, the catheter is held substantially loosely within each clamp, such that disconnection of the catheter from one clamp allows the catheter to slide past the other clamp to accommodate the free end of the catheter extending between the distal end of the catheter and the sleeve section length. Optionally, the sleeve includes a substantially C-shaped cross-section.

In one form, the gas delivery tube supplies breathing gas to the patient at a flow rate of between about 15 and about 150 L/min. Optionally, the gas delivery tube supplies breath to the patient at a flow rate between about 30 to about 120 L/min, or about 60 to about 110 L/min, or about 50 to about 150 L/min, or about 60 to about 100 L/min gas. In some forms, the gas delivery tube provides high flow breathing gas to the patient at a flow rate greater than about 30 L/min, greater than about 40 L/min, greater than about 50 L/min, greater than about 60 L/min, or greater than about 70 L/min.

Optionally, the gas delivery tube supplies breathing gas to the newborn infant patient at a flow rate of about 2 L/min/kg.

According to a thirteenth aspect, the present invention provides a gas sampling head removably connected to a distal end of a gas sampling conduit, wherein the sampling head includes a body including a substantially hollow interior region, the The substantially hollow interior region is configured to be in fluid communication with the inlet of the gas sampling conduit when connected to the gas sampling conduit, and wherein the body also includes a distal portion having a distal surface and an outer surface, wherein the gas sampling head further At least one gas-receiving aperture is included that is connected to the hollow interior region to receive exhaled or exhaled gas of the patient, and wherein the gas-receiving aperture is in fluid communication with the substantially hollow interior region of the body. At least one gas-receiving hole may be formed in both the distal surface and the outer circumferential side surface such that the gas-receiving hole extends from the distal surface and along the outer side surface. Optionally, the at least one gas receiving hole forms an elongated opening in the distal portion of the gas sampling head.

In one form, the distal end of the gas sampling tip is curved outward. Optionally, the distal portion of the gas sampling head is substantially spherical. In one form, the gas sampling head has a substantially cylindrical shape. In one form, the gas sampling head includes a body having a substantially cylindrical shape and a substantially spherical distal end.

In one form, the gas sampling head includes three gas receiving holes evenly spaced around the distal end of the sampling head. Each portion of the body located between the gas receiving holes forms a groove, wherein the grooves are substantially evenly spaced around the circumference of the distal portion of the gas sampling head.

Optionally, the gas sampling head is configured to receive, by the breathing apparatus, exhaled or exhaled gas from a patient supplied with breathing gas at a flow rate of between about 15 and about 150 L/min. Optionally, the gas sampling head is configured to be delivered by the breathing apparatus at between about 30 and about 120 L/min, or between about 60 and about 110, or between about 50 and about 150 L/min, or between about 60 and about Flows between 100 L/min receive exhaled or exhaled gas from the patient being supplied with breathing gas. In some forms, the breathing apparatus provides high flow breathing gas to the patient at a flow rate of greater than about 30 L/min, greater than about 40 L/min, greater than about 50 L/min, greater than about 60 L/min, or greater than about 70 L/min.

Optionally, the gas sampling head is configured to receive exhaled or exhaled gas from a newborn infant patient supplied with breathing gas by the breathing apparatus at a flow rate of about 2 L/min/kg.

In one form, the head is attachable to a gas sampling interface that includes a conduit including a first end in fluid communication with the respiratory gas monitor and a second distal end attached to the head, and the second The distal end includes at least one inlet for receiving exhaled or exhaled breathing gas from the patient, wherein at least a portion of the conduit is flexible to allow the inlet to be selectively positioned at the patient's mouth or nose.

According to a fourteenth aspect, the present invention provides a breathing apparatus comprising: a nasal cannula including at least one nasal cannula or outlet to be received in a user's nostril; a gas delivery tube, the a gas delivery tube in fluid communication with the at least one nasal cannula or outlet for supplying breathing gas via the at least one nasal cannula or outlet; and an attachment member for attaching the gas sampling interface to the nasal cannula, wherein the attachment member is integral with or attached to the breathing gas delivery tube, and the attachment member comprises: a sleeve at least partially surrounding a portion of the breathing gas delivery tube; wherein the sleeve comprises a At least one clip for receiving a portion of the gas sampling conduit for attaching the conduit to the breathing apparatus. Optionally, the cannula includes a substantially arcuate inner surface to enclose a portion of the breathing gas delivery tube. In one form, the clip is located on the outer surface of the sleeve. Preferably, the sleeve includes a pair of clips that are offset from each other. Each clip may optionally include a hook that includes a receiving area in which a portion of the catheter may be positioned to follow a tortuous path. In one form, the hooks face in opposite directions to each other. Preferably, the catheter is held substantially loosely within each clamp, such that disconnection of the catheter from one clamp allows the catheter to slide over the other clamp to accommodate the free end of the catheter extending between the distal end of the catheter and the sleeve section length. The sleeve may optionally comprise a substantially C-shaped cross-section.

In one form, the gas delivery tube supplies breathing gas to the patient at a flow rate of between about 15 and about 120 L/min.

In another form, the gas delivery tube supplies breathing gas to the neonatal patient at a flow rate of about 2 L/min/kg.

According to a fifteenth aspect, the present invention provides a method of making a dual lumen gas sampling catheter including a body including a gas lumen and a wire lumen, wherein the catheter is formed by co-locating the wire with the catheter body Extrusion is created to position the wire within the wire guide.

According to a sixteenth aspect, the present invention provides a method of manufacturing a dual-lumen gas sampling catheter, the dual-lumen gas sampling catheter including a body including a gas lumen and a wire lumen, wherein the catheter is formed by covering the catheter around the wire , to position the wire within the wire guide.

According to a seventeenth aspect, the present invention provides a method of sampling breathing gas from an apnea patient receiving high-flow respiratory therapy using the respiratory therapy system of the tenth aspect of the present invention, wherein the method comprises the steps of: approaching the patient The airway is used to locate the inlet of the gas sampling interface, the breathing gas sample is received through the inlet, and the breathing gas monitor is used to determine whether the patient's airway is open.

Optionally, the breathing gas monitor may also measure the volume of breathing gas or one or more components of the breathing gas.

The present invention consists of the foregoing, and also contemplates structures of which only examples are given below.

In summary, the present invention relates to respiratory gas delivery and sampling systems, gas sampling systems, gas sampling interfaces, and gas sampling heads that can be used to sample a patient's exhaled and/or exhaled gas. The gas sampling system includes a respiratory gas monitor in fluid communication with the gas sampling interface, which includes the gas sampling head of the present invention. The gas sampling interface includes a gas sampling conduit, and the gas sampling head is located at the free end of the conduit. The gas sampling interface can be configured to allow the gas sampling head to be selectively positioned at the mouth (middle) or at the nostrils of the patient's nose (middle). The sampling head includes at least one inlet to receive exhaled or exhaled gas from the patient. The sampling head may also be configured to include a cover or structure to help prevent fluids, such as moisture or bodily fluids, from entering the sampling head. Additionally or alternatively, the sampling head may be configured to prevent or reduce the likelihood that the head will stick to the patient (eg, the patient's tongue or cheek). In some forms, the cover or structure of the sampling head can help prevent fluid ingress, and can also help prevent aspiration of the patient. The gas sampling interface may include a filter at the head or any other location of the gas sampling cavity of the sampling interface to prevent fluids (eg, moisture or body fluids) from entering or moving along the gas sampling cavity into the respiratory gas monitor.

Various gas sampling interfaces/breath sampling interfaces for use with respiratory gas monitors of gas sampling systems will now be described. It should be appreciated that any of these interfaces may be used in combination with (or connectable to) a breathing gas delivery and sampling system including a breathing apparatus for delivering breathing gas to a patient. Each gas sampling interface can sample the patient's breath and/or breath. Each interface can be used to sample nitrogen, O ₂ , anesthetic gas and/or CO ₂ . Alternatively, two sampling interfaces can be used, one for sampling nitrogen and the other for sampling _CO2 . The interface will sample exhaled and/or exhaled gas, and can be fluidly connected to a separate gas analyzer to identify _CO2 and nitrogen in exhaled and/or exhaled gas. It will be appreciated that exhaled air is the air that leaves the patient's lungs due to gas exchange in the lungs. Exhaled air is the gas expelled from the lungs (eg, diffused gas from the lungs) when the patient is not breathing spontaneously (eg, when the patient has difficulty breathing). Exhaled air is the gas pushed out of a patient's lungs as a result of the patient's spontaneous breathing.

The gas sampling interface of the invention disclosed herein may be disposable or reusable. A filter can be connected to the end of the sampling interface, between the interface inlet and the sampling conduit, to allow the sampling conduit to be reused. The gas sampling interface 100 and/or filters may vary for each patient. The disclosed gas sampling interface and gas sampling catheter can be used alone to engage with a portion of a patient's face, or the gas sampling interface and gas sampling catheter can be attached to a breathing apparatus (such as a nasal cannula) that delivers breathing gas to a patient. , nasal masks, masks, or other forms of patient interface).

The gas sampling interface of the present invention can be used with respiratory devices that provide high flows of breathing gas to a patient. Typically, breathing equipment provides high-flow breathing gas to apnea patients (eg, during anesthesia), but devices and interfaces can also be used to measure breathing gas in spontaneously breathing patients. To provide breathing gas at high flow rates, for adult patients, the gas can typically flow between about 15 L/min to about 150 L/min. Exemplary flow rates of breathing gas provided by the patient interface to the patient are between about 15 to about 150 L/min; between about 30 to about 120 L/min; between about 40 to about 100 L/min; about 50 to about Between 80 L/min; between about 60 to about 100 L/min; and between about 35 to about 75 L/min. In other examples, high flow breathing gas may be supplied to the patient at a flow rate between about 30 to about 120 L/min, or about 60 to about 110 L/min, or about 50 to about 150 L/min, or about 60 to about 100 L/min suffer. In some forms, the patient may be supplied with high flow breathing gas at a flow rate greater than about 30 L/min, greater than about 40 L/min, greater than about 50 L/min, greater than about 60 L/min, or greater than about 70 L/min. What might be considered "high flow" may vary, depending on the size of the patient. For example, a newborn infant patient may be supplied with high flow breathing gas at a flow rate of about 2 L/min/kg. In some forms, the gas sampling interface is configured to have an adaptive shape and/or position relative to the breathing apparatus. By providing the interface with an adaptable shape, it is possible to manipulate the interface to best engage with the patient, such as by hanging on the patient's lips, cheeks or nostrils. It is also possible to adjust the orientation and position of the interface by manipulating the interface close to the patient's mouth or nose. This allows the clinician to choose the best location for the interface, and can easily change that location if needed. By providing the interface with an adjustable position relative to the breathing apparatus, the interface can be directed towards the patient's mouth or nose as described above, and the length of the free end portion of the interface in relation to the breathing apparatus can also be easily adjusted. An interface with an easily adjustable length free end portion allows the interface to be used on patients with faces of different sizes. For example, when used with children, the gas sampling interface of the present invention requires a shorter free end portion than when used with adults. Where the sampling interface of the present invention is adjustable in shape and/or position, the interface is particularly versatile and can be used for a wide range of patients and medical procedures. For example, the sampling interface provides a selectively positionable device that can be moved between the mouth and nose depending on whether the patient's mouth is open and the type of medical procedure being performed.

FIG. 1 shows an embodiment of a gas sampling interface 100 . The gas sampling interface 100 includes a gas sampling conduit 101 having a body 103 that is preferably partially or fully formed from a substantially cylindrical wall (as shown in FIG. 1 ) to provide the body 103 with a flow path along its length. Substantially circular cross section. The catheter shown in Figure 1 has a single lumen extending along the length of the catheter and is therefore referred to in this specification as a single lumen catheter. However, the gas sampling conduit may include one, two or more lumens within the conduit. A gas sampling catheter comprising two lumens within the catheter is referred to in this specification as a dual lumen catheter. Both lumens of the dual lumen catheter may extend only partially along the entire length of the catheter, or the first support lumen may extend only partially along the length of the catheter (as will be described in further detail later in this specification), and The second air lumen may extend substantially along the entire length of the catheter,

The dimensions of the catheter and its lumen(s) are important to its maneuverability. It will be appreciated that the outer diameter of the catheter will be determined by the desired inner diameter of the lumen(s) and the material from which the catheter is made. It is important that the inner diameter(s) of the lumen(s) are not so large that the catheter is too large for the patient to comfortably use and easily maneuver into the desired shape and position. It is also important that the inner diameter(s) of the lumen(s) are not so small relative to the outer diameter of the conduit that airflow through the conduit is unduly obstructed, or that the walls of the conduit are so thick that it is difficult to Manipulate the catheter into the desired shape and substantially maintain the catheter in that shape.

Preferably, the body of the gas sampling conduit 101 has an outer (or outer) diameter of between about 2.5 mm and about 5.0 mm. The diameter may be about 3.5 mm to about 4 mm, or about 3.0 mm to about 3.5 mm, or about 3.1 mm to about 3.4 mm, or about 3.2 mm to about 3.3 mm. Preferably, the body of the gas sampling conduit has an outer diameter of about 3.8 mm. The inner diameter of the gas sampling catheter (where the catheter has a single lumen) is preferably between about 0.5 mm and about 2 mm to correspond to the inner diameter of the main sampling tube or gas sampling tube of the respiratory gas monitor without causing Extra resistance to flow. For example, the inner diameter of the catheter may be approximately 1.2 mm to 1.4 mm. Preferably, the inner diameter is about 1.4 mm.

In one form, the tubular body of the gas sampling conduit 101 has a wall thickness of about 0.9 mm. In this form, the body 103 of the catheter may have an outer diameter of about 3.0 mm and an inner diameter of about 1.2 mm. Gas sampling conduits of this form preferably include a single gas lumen within the conduit.

In one form, the outer diameter of the dual lumen catheter is between about 2.5 mm and about 5.0 mm. In one form, the outer diameter may be about 3.2 mm. The diameter may be about 3.5 mm to about 4 mm, or about 3.0 mm to about 3.5 mm, or about 3.1 mm to about 3.4 mm, or about 3.2 mm to about 3.3 mm. Preferably, the body of the gas sampling conduit has an outer diameter of about 3.8 mm. In another form, the outer diameter is about 4.0 mm. The lumens within the catheter can have the same diameter or different diameters. For example, the lumens may each have an inner diameter of about 1.2 mm. In one form, the dual lumen catheter has an outer diameter of about 3.8 mm, and each lumen has an inner diameter of about 1.4 mm. Alternatively, for example, the first lumen may have a diameter of about 1.0 mm, and the second lumen may have a diameter of about 1.3 mm. In another form of the dual lumen catheter, the catheter may have an outer diameter of about 3.8 mm. In this form, the first lumen may have an inner diameter of about 0.6 mm, and the second lumen may have an inner diameter of about 1.4 mm.

It is desirable that the outer diameter of the catheter is relatively small so as to occupy less space in the patient's mouth.

In one embodiment, as shown in FIG. 2 , the gas sampling interface includes a dual lumen conduit 201 . This catheter is similar to the catheter shown in Figure 1 and like numbers (plus 100) are used to denote like parts. In the embodiment shown in Figure 2, the catheter body 203 has a circular cross-section along its entire length. The catheter includes a flexible elastic support structure that allows the catheter to be manipulated into a desired shape (eg, a hook-like shape). The support structure can take many different forms. For example, the support structure may comprise a wire, rod or band of flexible elastic material (eg metallic material) extending along at least a portion of the catheter (preferably at the free end portion of the catheter). In one form, the catheter includes a first support lumen in which a support structure (eg, a guidewire) can be positioned. The wire may be inserted into the lumen or coextruded with the catheter, or a portion of the catheter may be overmolded around the wire. In other forms, the support structure may be formed around the outer wall of the catheter, or the outer wall may be made of a suitable material that provides the support structure.

In the embodiment shown in Figure 2, the catheter includes a first support lumen 201 to accommodate a support structure in the form of a wire within the first lumen. The first support cavity or wire cavity has a substantially circular cross-section along its entire length. The second air cavity 202 for receiving exhaled and/or exhaled gas has a substantially crescent-shaped cross-section along its entire length. The first cavity 201 is located inside and on one side of the second cavity 202 such that the crescent-shaped cross-section of the second air cavity is formed by the shape of the open space surrounding the first inner cavity 201 . In alternate embodiments of the dual lumen catheter 900, each lumen 911, 913 may have a substantially D-shaped cross-section (as shown in FIG. 9), or a substantially semi-circular cross-section, or a substantially The cross section of the upper circle. Preferably, the cross-sectional area of the air cavity is greater than about 1.3 mm. Preferably, the height of the air cavity is greater than about 1.5 mm. Preferably, the width of the air cavity is greater than about 1.5 mm. Figure 13 shows a dual lumen catheter wherein each lumen includes a substantially circular cross-section along its length.

The gas sampling conduit 101 may consist of or contain a polymeric material. The material can be any suitable medical material such as PVC, TPU or silicone. The hardness of the material is preferably from about 30 to about 85 on a Shore A durometer. The material is preferably transparent so that the interior of the catheter is visible, for example, to see if saliva, blood or other bodily fluids that may be present have been drawn into the catheter. The sampling catheter material may include a hardness of less than 90 on a Shore A durometer. This reduces the torque of the catheter on the patient end of the interface (compared to stiffer catheters), and thus reduces the chance of the sampling catheter falling out of the patient's mouth or nostrils. Softer materials are also more comfortable on the patient's face. Materials may contain polyurethane or silicone. Alternatively, the material may comprise PVC.

The gas sampling conduit 101 has at least one inlet, or gas receiving hole or opening 107 for receiving the patient's exhaled and/or exhaled gas. The inlet 107 may be formed in the distal portion of the catheter, such as in the outer wall of the catheter or at the distal end of the catheter. In the embodiment shown in Figure 1, the inlet is located at the distal end 108 of the body 103 of the catheter. The catheter also has an outlet 109 for delivering exhaled and/or exhaled gas to a breathing gas monitor, which may be a capnogram/capnograph or other form of gas monitor, to monitor _CO levels and/or levels of other breathing gases. The outlet 109 may be in fluid communication with a gas sampling tube or gas sampling line fluidly connected to the respiratory gas monitor. In another form, the outlet of the gas sampling conduit may be directly connected to a breathing gas monitor.

The catheter is preferably at least 30 cm long. This means that if the patient is on the catheter, any connector/luer connecting the catheter to the gas sampling tube of the respiratory gas monitor will not be located under the patient's head (which may be uncomfortable).

The catheter 101 can be configured to take a desired shape to engage with a patient's face such that the catheter can be easily attached to/engaged with the patient's face and disengaged/ Disengage from the patient's face. In a preferred form, the catheter may be shaped as a hook to hook around the patient's lips or teeth or around the patient's cheek or nostrils. In this form, it may be unnecessary to glue the catheter to the patient's face so that the catheter can be quickly and easily positioned in the desired location and removed after use.

In one form, for example, as shown in Figs. As shown, the catheter 101 includes a hook portion 105 that is preferably located at the distal end portion of the catheter. In one form, the tubular structure of the catheter may include a flexible elastic support structure that allows a portion of the catheter to be formed into a hook-like shape and substantially maintain that position. In another form, the tubular structure of the catheter can be connected to a rigid or semi-rigid hook to form a catheter having a hook portion. In another form, the catheter may be fabricated by including a hook portion, such as an end formed in a hook-like shape. The hook portion 105 forms a hook-like shape for engaging a portion of the patient's face.

The hook portion 105 of the catheter 101 is adapted to engage the patient's face at or near the orifice in the patient's face. In one embodiment, the hook portion 105 is adapted to engage with the patient's mouth or a portion of the patient's mouth. In use, the hook portion 105 surrounds the patient's cheek and enters the patient's mouth. The hook portion 105 enables the head 108 and inlet 107 of the catheter 101 to be suspended within the patient's mouth, if desired. In another embodiment, the hook portion 105 is adapted to engage the patient's nose or a portion of the patient's nose, such as the patient's nostril or nostrils. In this embodiment, the head 108 or inlet end of the catheter may be suspended or positioned at least partially within or within the patient's nostrils, or may be suspended or positioned at least partially adjacent the nostrils/nostrils.

The hook portion of the catheter may comprise a semi-rigid or rigid material that forms a flexible elastic support structure or spine that allows the catheter to be bent or manipulated into a desired shape. In some forms, the catheter can be configured to substantially retain the desired shape indefinitely. In other forms, the catheter may be configured to substantially retain the desired shape until manipulated by the user to form a different shape.

In one form, the flexible elastic support structure may comprise a length of extending wire such as, for example, a cable or rod located within a conduit. The wires are preferably metal wires. The guidewire may extend along one or more portions of the catheter, or the guidewire may extend along substantially the entire length of the catheter. The distal or patient end of the lead may be coated with a soft material so that it does not chafe or scratch the patient's face. Alternatively, the patient end of the lead can be positioned far enough back into the catheter so that it does not extend beyond the distal end of the catheter. In a further alternative, the end of the wire may be sealed within the wall of the catheter. In a further alternative, the wire may be located within the support lumen/wire lumen of the dual lumen catheter, and the patient end of the wire may be secured at one or more points along the inner wall of the wire lumen to hold the wire in place and prevent the lead from moving out of the lumen.

In another form, the catheter may include at least one lumen that serves as both a guidewire/support lumen and an air lumen. In this form, the catheter may comprise a wire having a diameter smaller than the inner diameter of the lumen. The wire may be retained within the lumen at one or more locations. In such an arrangement, the catheter can be bent around the guidewire, but one or more gaps are provided between the guidewire and the inner wall of the lumen so that gas can pass along the lumen for sampling by the respiratory gas monitor. The lumen cannot completely seal the incompressible wire to prevent complete blockage.

A length of malleable wire may occupy at least the hook portion of the catheter, or the wire may extend substantially the entire length of the catheter. For example, in the dual lumen catheter shown in FIG. 2 , the guidewire 210 may occupy one or more portions of the first lumen 204 of the dual lumen catheter 201 , or the guidewire may extend substantially the entire length of the first lumen 204 . The presence of wire 210 provides rigidity to conduit 201 and gas sampling interface 200 . The guidewire 210 is also flexible to allow some adjustment of the first support catheter 201 (and thus the catheter 201) to further customize the shape of the patient's facial interface. In particular, the shape of the hook portion can be formed by bending the wire 210 to form the desired hook shape for engagement with the patient's face.

The wire may comprise a stainless steel wire that can be bent/reshaped multiple times without breaking. The diameter of the wire may be between about 0.4 mm and 1.0 mm, and preferably about 0.6 mm or 0.7 mm in diameter. Preferably, the wires are 304 grade. These properties result in suitable ductility to allow the user to easily reshape/bend the catheter by hand. In another form, the wire comprises aluminum wire. In another form, the wire comprises Nitinol wire.

In one form, the wire 210 is located on the inside curve of the hook portion. This is to reduce the risk of kinking the gas sampling tube when bent. Alternatively, the guidewire 210 may be positioned on the outside curve of the hook portion, or along the sides, or at any other orientation or location around the length of the catheter.

Figures 12 and 13 illustrate another form of dual lumen catheter 1200. The first wire/support cavity 1211 contains wires that form a plastic shape. The second air chamber 1213 can be connected in fluid communication with a gas sampling tube (which is in fluid communication with the breathing gas monitor), or in direct fluid communication with the breathing gas monitor (where the sampling system does not include a connection between the monitor and the sampling conduit) sampling tube). In this dual lumen catheter, the catheter is preferably curved or formed with a catheter located inside the curve of the hook portion and a catheter located outside the curve. This arrangement results in lower flow resistance than if the cavities were positioned side-by-side around the bend. The wire is fed through a first lumen 1211 located on the inner curve of the hooked portion of the catheter. This reduces the risk of the wire piercing the catheter wall and reduces the risk of the wire kinking the catheter when the wire bends.

FIG. 13 shows a cross-section of a dual lumen catheter including a first guidewire lumen 1211 and a second air lumen 1213 . In one form, the air cavity 1213 may include an inner diameter of about 1.2 mm to correspond to the inner diameter of a gas sampling tube of an anesthesia machine or other form of breathing gas monitor or to the inlet of a breathing gas monitor. In another form, the air lumen 1213 may have an inner diameter of approximately 1.4 mm, and the wire lumen may have an inner diameter of approximately 0.6 mm. Smaller inner diameters will increase resistance to flow and may increase the chance of blockages in the gas sampling conduit and cause an alarm. It will be appreciated that the inner diameter may optionally be selected or designed to correspond to the inner diameter of the gas sampling tube of an anesthesia machine or breathing gas monitor, or to the inlet of a breathing gas monitor. However, as discussed above, the inner and outer diameters of the lumen of the catheter can vary.

The wire lumen 1211 may include an inner diameter of about 1.0 mm. This diameter is to accommodate 0.7mm wire. It will be appreciated that the inner diameter will be selected or designed to accommodate the wire.

The outer diameter of the catheter may be about 3.1 mm. This diameter was chosen because it allows catheters to include catheters with inner diameters of 1.2 mm and 1.0 mm and (as described above) with sufficient wall thickness. Inclusion of a small outer diameter catheter is advantageous for reducing the size of the interface in the patient's mouth to improve patient comfort and allow the clinician greater accessibility in the mouth. The smaller diameter conduit also allows the interface to fit under the bite block.

As shown in Figure 13, the lumen of the catheter may preferably, but need not be, round or circular. Rounded cavities and cavities are more resistant to kinking. In one form, the wall thickness WT1 between the lumens may be greater than the outer wall thicknesses WT2 and WT3 of the lumens (the wall thickness of the catheter). This wall structure also reduces the risk of kinking in the catheter when the catheter is bent; for example, if the user reshapes the catheter to create a tighter bend in the hook portion. In a preferred form, the gas sampling interface and gas sampling conduit comprise a dual lumen conduit having an outer diameter of about 3.8 mm. The catheter includes a first wire lumen (to receive a wire having an outer diameter of about 0.6 mm) with an inner diameter of about 0.6 mm, and a second air lumen with an inner diameter of about 1.4 mm. Both cavities have substantially circular cross-sections.

In a dual lumen catheter, the guidewire preferably extends down a first guidewire lumen within the catheter. In one form, the lead terminates along a portion of the lumen or catheter. For example, the wire may extend up to about 60mm from the free end of the catheter. In another form, the wire may extend substantially the entire length of the catheter. Optionally, the wire is coextruded with the tubular material of the catheter. When the catheter is bent, the free end of the wire may be substantially aligned with the free end of the catheter (or may be slightly retracted from the free end of the catheter). Optionally, the free end of the wire in the curved catheter can also be substantially aligned with the other end of the wire. This allows for maximum clamping force of the hooked portion of the catheter on the cheek. This design also minimizes the rigid length that extends past the pinch point, thereby reducing the torque on the pinch point that can disengage the interface.

In one embodiment, the catheter is manufactured to include a hook portion. For example, during manufacture, the catheter can be started in a straight state and then can be bent or hooked using a clamp. Heat may also be applied to the catheter for a period of time to shape the catheter. In another form, the conduit may be a thermoplastic tube. During manufacture, the catheter can be formed into a hooked shape by starting in a straight state and prior to bending or forming a permanently altered hooked shape using a clamp and brief heating to set the catheter into the desired shape.

In the embodiment shown in FIG. 1 , the gas sampling interface 100 is composed of a gas sampling conduit 101 , the gas sampling conduit 101 includes a section of pipe, wherein the interface end of the sampling conduit forms a hook shape as shown in FIG. 1 . This embodiment can be a single lumen catheter 1 interface or a dual lumen catheter interface. In other forms, the gas sampling conduit 101 may include sampling heads such as those described later in this specification, such that the conduit and head combine to form a gas sampling interface.

Figure 3 shows a spline curve representing a series of curves applied to one embodiment of the conduit of the interface. The catheter may include an additional curved portion directly adjacent to the hook, the curved portion being curved towards the interior of the hook curve. That is, when viewed from the outside, the catheter has a generally concave portion 317 that enters a generally convex hook portion 315 that enters another generally concave hook portion 315 Section 319. The concave portions 317 and 319 may have the same or different curvatures. The resulting combined shape provides a central pinch zone. Narrow pinch points improve patient comfort by minimizing pinch point area. In use, the gripping area can contact the inside and outside of the patient's cheek or nostril and help maintain the interface. The additional curved and hooked portions additionally provide some resistance to deformation of the catheter, which may exert a small reaction force on the inside and outside of the patient's cheek to help maintain the interface.

In one embodiment, a gas sampling interface or conduit can be hooked around the guide cannula to sample exhaled and/or exhaled gas from the patient's nostrils.

The embodiment shown in Figures 7 and 8 would be advantageous in this configuration because the openings would capture exhaled and/or exhaled air from the patient's nostrils.

One of the additional concave portions 319 may extend between the convex portion 315 and the distal end of the catheter. In use, this additional concave curvature can move the sampling catheter out of contact with the patient's face. A further convex curved portion 321 may optionally be provided between the additional concave curved portion and the distal end of the catheter. This further convex curved curve 321 may position the distal end of the catheter such that (in use) the sampling catheter extends generally parallel to and offset from the patient's cheek. This reduces the torque of the sampling catheter on the hook on the patient's face, thereby reducing or preventing the risk of displacement.

An additional concave curved portion 317 may extend between the hook curved portion 315 and the inlet of the catheter. This additional curved portion 317 can move the inlet of the catheter out of contact with the inside of the patient's cheek. To avoid, or at least substantially inhibit, complete or partial blockage of the catheter and/or sampling catheter with saliva or other potentially present bodily fluids (eg, blood), it is desirable to move the inlet of the catheter away from the interior of the patient's cheek.

The hook shape may include a series of curves in a substantially two-dimensional plane and include at least one curve or curve that curves substantially inward to form the hook. Hook shapes may include "J", "L", "U", "V", "Ω" or "hairpin" shaped conduits, or any combination thereof. That is, the hook portion may have one or more curved portions, one or more straight portions extending at an angle relative to adjacent curved portions, or a combination of straight portions and curved portions to form the hook. In one embodiment, the hook may comprise two generally parallel sections with curved or angled sections between the parallel sections to form the hook. This increases the surface area of the narrow pinch points in contact with the cheeks, increasing the stability of the face.

To avoid blocking or clogging the inlet 107, various embodiments of the head are contemplated (as will be described below). It should be understood that the conduit may include any suitable head for receiving exhaled and/or exhaled gas.

In one embodiment, as shown in Figures 4-6, the inlet 408 may have a mouth 407 having a larger cross-sectional area than an adjacent portion of the catheter body. This interface is similar to that shown in FIG. 1, and similar numbers are used to denote similar parts plus 300 units (ie, 103 and 403). The mouth 407 preferably has a shape that diverges outwardly from the cavity. Thus, the inlet 408 has an outer shape that diverges outwardly from the body 403 . The mouth 407 may be frustoconical, conical, flared, bell-shaped, or the like. This shape increases the open area over which the liquid saliva meniscus can be formed. As a result, the surface tension in the liquid saliva is reduced, making it less likely that a blockage will form in the duct.

In one embodiment, as shown in FIG. 6, the head 608 may have alternating or varying depths when viewed in cross-section. This interface is similar to that shown in Figure 1, and like numbers are used to denote like parts plus 500 units. For example, an undulating waveform 607 or cutout around the perimeter of the head may be apparent when viewed in cross-section. This shape disrupts the area on which a meniscus of liquid saliva or other bodily fluids can form. Thus, the stability of the meniscus can be reduced, and the likelihood of saliva blockage in the catheter can also be reduced. This shape also prevents complete blockage by the internal tissue of the mouth (or nose). The head shown and described with respect to Figure 6 can be used with either a single lumen catheter interface or a dual lumen catheter interface.

In another embodiment, such as shown in Figure 7, the catheter 701 may include a plurality of inlets/openings 723 around the perimeter of the head and/or along the distance of the catheter from the head. This interface is similar to that shown in Figure 1, and uses similar numbers to denote similar parts plus 600 units. In the event that one opening 723 is blocked, multiple openings 723 provide alternate entry points for receiving exhaled and/or exhaled gas. The plurality of openings 723 may have substantially the same size or varying sizes. The plurality of openings 723 may be located along a particular side, or have a larger (compared to the other) distribution of openings 723 toward a particular side of the head 708 . The shape of the opening 723 may vary. The distribution, size and/or shape of the openings 723 may vary in combination. Figure 7 shows a portion of this alternative embodiment with diamond shaped openings. Liquids have a tendency to be sucked into corners. The diamond-shaped opening will help draw saliva or other fluids (such as blood) from the center of the blocked hole, and will also help break up the meniscus. Figure 8 shows a portion of a similar embodiment. FIG. 8 has a circular opening 823 . It will be appreciated that the head shown in FIG. 7 and the head shown in FIG. 8 may be substantially straight (as shown in these figures), or may follow a spinal curvature (as shown in FIG. 3 and related). said). The heads shown and described with respect to FIG. 7 can be used with either a single-chamber interface or a dual-chamber interface.

The diameter or width of the opening may be greater than the inner diameter of the air cavity. This means that the flow resistance of each opening is no greater than that of the air cavity. Therefore, if only one opening is exposed, a breathing gas monitor such as an anesthesia machine will not have to draw against the greater resistance (which may cause blockage and cause an alarm). Any suitable inlet/opening will be successful as long as the opening has the same or greater pressure drop (ie, the same or less resistance to flow) than the air cavity itself.

In one form, the inlets/openings 723 and 823 simply pierce the outer wall of the air lumen within the catheter, so as to completely enclose the guidewire within the guidewire/support lumen of the catheter. The opening is preferably not located on the side of the catheter that contacts the inside of the patient's cheek to prevent the catheter from sucking onto the cheek.

The opening may be located in a portion of the catheter extending from the distal end of the catheter to a catheter length marking the maximum insertion depth. This ensures that the opening only draws air from inside the mouth and does not entrain any ambient air that could dilute the gas reading.

The opening may increase in size towards the end of the conduit. The opening sizes are chosen so that the resistance to flow through each opening is equal.

The header of the interface may optionally and/or additionally include header structures that further prevent the ingress of saliva or other bodily fluids (eg, blood) that may be present (as will be described below).

In another embodiment, the head structure may include a filter at least partially surrounding the head of the interface, or the filter may be positioned inside the catheter at the distal end of the catheter, or may be positioned within the head. The filter may be substantially porous to allow exhaled and/or exhaled air to pass through the filter and into the head of the interface. Additionally and/or alternatively, the filter may include openings (in addition to the porous openings) to allow the passage of exhaled and/or exhaled gases. The filter may also absorb moisture, saliva, or other bodily fluids (eg, blood) that may be present to prevent, or at least substantially inhibit, blockage or blockage of the catheter. In one form, the filter may comprise a substantially absorbent porous sponge, foam, or other suitable porous material. In another form, the filter can include a substantially hydrophobic material (eg, such as a hydrophobic foam material) that repels fluid/moisture while allowing exhaled or exhaled air to pass through the filter and into the sample head. Suitable hydrophobic foam materials for use in such filters include, but are not limited to, open cell polyurethane foam with hydrophobic coatings (which can be of varying densities) and microporous sintered polytetrafluoroethylene. Another suitable material for use as a hydrophobic filter is a hydrophobic textile (eg WrapPel) made of 100% filament polyester coated in a hydrophobic fluorocarbon. Other possible materials for hydrophobic filters could be WrapPel and Gore-Tex. In one form, the filter may form the sampling head such that the sampling head consists of the filter. In another form, the filter may substantially surround or partially surround the sampling head. In another form, a filter may be placed inside the sampling head or inside the sampling conduit to prevent fluid (eg, moisture) from entering the gas sampling conduit from exhaled or exhaled gas or body fluids, or when fluid has entered the gas sampling conduit Move the gas sampling tube up.

Alternatively or additionally, a filter for separating fluid from gas can be placed anywhere along the length of the gas sampling conduit to prevent fluid from moving up the sampling conduit and into the breathing gas monitor. Help protect breathing gas monitors.

In another embodiment, the head structure may comprise a shroud, cage, roller or spacer surrounding the head of the interface. In use, a hood, cage, roller, or spacer abuts the patient's inner cheek to move the head of the interface away from the patient's inner cheek to reduce the impact of saliva or other bodily fluids on the exhaled and/or exhaled breath receiving head. possibility. The hood, roller or spacer may be formed integrally with the conduit or separately from the conduit.

10-13, further examples of conduits and gas sampling interfaces will now be described.

Figure 10 shows a spine for one example of a hook shape. The shape of the interface on the outside of the patient's cheek is preferably curved to follow the shape of the patient's cheek. This reduces the distance from the patient's face to the interface, reducing torque and improving stability. The shape also reduces or eliminates the chance of the tip of the interface poking into the patient's face, improving comfort. 10 and 11 depict exemplary spines or shapes. The line shown is the centerline of any conduit cross-sectional profile. The hook shape is a smooth curve to prevent kinks in conduits that can interfere with airflow and cause blockages.

The depth of insertion of the catheter into the patient's mouth or nose can be selected by the clinician. Typically, the insertion depth is greater than 10mm, preferably greater than 20mm. An insertion depth of 10mm (or less) may allow the interface to roll out of the patient's mouth (especially when the patient is sitting upright or semi-upright). The gap formed at the end of the hook (ie, the space between the distal end of the catheter and the substantially straight portion of the catheter body) is preferably about 5 mm to provide a clamp on the patient's cheek. The longer insertion depth also allows the catheter to extend beyond the natural location of the patient's tongue tip. This means that patients are less likely to block the tip with their tongue or push the interface out of their mouth. When the patient is not used to the foreign body in their mouth, they may try to remove the foreign body with their tongue; so this can be a problem.

Referring to Figures 14-25, an alternative embodiment of a catheter with a cover will now be described. As mentioned above, if the inlet at the distal end of the catheter is blocked, the catheter may have several small inlets/openings or one larger inlet/opening 1427 near the tip of the catheter to provide an alternative gas path. The cover shown and described with respect to Figures 14-25 prevents, or at least substantially prevents, the opening(s) from being blocked. The shield may have an extension that is curved around the hook portion to prevent, or at least substantially prevent, the outlet of the shield from being inserted into the mouth through the patient's lips. The cover may be non-circular to prevent, or at least substantially inhibit, the patient's cheek from being completely encapsulated and/or sealed around the cover. The hood may include cutouts to allow gas entry. The cover may include one or more protrusions that prevent the patient's cheeks or lips from sealing over the opening(s). The one or more protrusions allow saliva/blood to drain from the tube opening(s). In one form, the cover may form a separate element that is attached to the conduit. Alternatively, the cover may have a triangular shape. In one form, the cover may only partially cover the inlet(s)/opening(s) such that the cover does not completely cover the opening(s). In one form, the cover may cover only some of the inlets/openings of the conduit.

The inlet(s)/opening(s) of a catheter with multiple openings can be sized to provide a similar flow resistance to a single inlet formed in the distal end of the catheter, so that the gas passes evenly through(s) Open your mouth. The opening may also be sized to minimize the maximum velocity through the catheter to reduce the risk of possible saliva or other bodily fluids (eg, blood) being drawn into the catheter. For example, for a catheter comprising a single lumen with an inner diameter of 1.2 mm, the oval hole may be 1 mm by 5 mm. Figure 14 shows an oval opening without a cover. Figure 15 shows an embodiment with a cover.

Figure 15 shows a gas sampling interface or conduit with a cover 1529 surrounding the conduit to cover the opening in the conduit to prevent partial or complete blockage of the opening. The cover of Figure 15 is in the form of a substantially cylindrical element.

The mask may have non-flat areas to increase the surface area and angle over which the interior of the patient's cheek must seal to create an obstruction.

Figure 16 shows a cover with internal ribs 1630 to keep cover 1629 away from the exterior of the catheter and the opening protected by the cover.

In one form, as shown in Figure 17, the cover 1729 may extend past the patient's lips in use, so that if the patient's lips seal around the interface, gas may still be entrained from the outside air to prevent partial or complete Occlusion and subsequent machine alarms.

Alternatively, the catheter may include a stop 1830 (shown in FIG. 18 ) at the curved portion of the hook portion to prevent the distal end of the shield 1829 from being inserted through the patient's lips into the patient's mouth or into the nostril too deeply . In other words, the barrier may create a depth limit that prevents the gas sampling catheter from being inserted too deep into the patient's mouth or nostrils.

The hood can open down the entire length of one side so that if the patient's lips are tightly closed, gas from the patient's mouth can still enter the gas sampling conduit through the opening.

Figure 19 shows a cover 1929 in the form of an elongated element having a generally C-shaped cross-section.

The cover may be non-circular to at least substantially inhibit the patient's cheek from being completely encased and/or sealed around the cover. For example, Figures 20 and 21 show a square cover 2029/2129 having a substantially square cross-section. The hood has cutouts 2032/2132 or openings to allow gas to enter the sampling conduit through the hood when the patient's lips are closed.

Figures 22 and 23 show the form of a hood with protrusions that prevent the patient's cheeks or lips from sealing against the gas sampling conduit inlet. FIG. 22 shows a cover having a plurality of protrusions in the form of sleeves to form toothed elements 2229 . FIG. 23 shows a cover including corrugated protrusions to form curved members 2329. Each arrangement of protrusions forms a shield that allows saliva and/or other bodily fluids (eg, blood) that may be present to drain from the catheter inlet, reducing the risk of inlet blockage.

The cover may be integral with the conduit or attached to the conduit as a separate component. Alternatively, the shield may be connected to or fed through a portion of the conduit extending out of the patient's mouth and attached to the patient's mouth to reduce the risk of portions of the shield falling off within the patient's airway.

Figure 24 shows an example of a cover 2429 with alternative protrusions comprising outwardly extending arms forming a generally triangular or V-shaped element around the conduit inlet. Figure 25 shows a cover in the form of a planar element with arms protruding from the sides of the catheter.

In one form, the gas sampling interface may be attached to the breathing apparatus via an attachment member, which may be a separate element attachable to both the breathing apparatus and the sampling interface, or may form part of the breathing apparatus (or An attachment member that is integral with the breathing apparatus), or may be an attachment member that forms part of (or is integral with) the sampling interface.

The sampling interface can be attached to the breathing apparatus at any suitable location. For example, where the breathing device is a nasal cannula, the sampling interface may be attached to the manifold of the catheter, or to the strap of the headgear, or to the breathing gas delivery tube. Where the breathing device is a mask, the sampling interface may be attached to the frame of the mask, the seal of the mask, or the straps of the mask headgear or breathing gas delivery tube.

Figure 26 illustrates a form of breathing apparatus that includes a gas sampling interface of a form of the present invention connected to or integral with the breathing apparatus. The breathing apparatus includes a nasal cannula connected to a gas sampling interface. The nasal cannula includes a manifold and at least one nasal cannula or outlet extending from the manifold to be received in a user's nostrils. The nasal cannula also includes an attachment member for securing the gas sampling catheter relative to the nasal cannula such that the inlet(s) of the gas sampling catheter receive patient exhaled and/or exhaled gas. In alternative embodiments, the breathing apparatus may include a different form of patient interface (eg, a face mask, nasal interface, or full face mask) and attachment members for securing the gas sampling catheter relative to the patient interface such that the (multiple) a) inlet to receive patient exhaled and/or exhaled air. Respiratory equipment provides high flow of breathing gas to the patient.

The attachment member may comprise any suitable attachment system to attach the gas sampling catheter to a nasal cannula or other form of patient interface. For example, the attachment member may include a clamp, a pair of clamps, or a strap. The attachment member may comprise an elastomeric material.

Where the patient interface is a nasal cannula, the attachment member may be integrated with the manifold of the cannula and/or at least one nasal cannula or outlet. Alternatively, the attachment member may be a separate element attachable to the manifold and/or at least one nasal cannula or outlet or to another suitable part of the breathing apparatus, such as a breathing gas delivery tube.

Figures 27-34 illustrate various embodiments of attachment members configured to attach the catheter of the breath sampling interface 100 to the manifold or headgear of the cannula of the breathing apparatus (both shown in Figs. 28, Fig. 30, Fig. 32 and Fig. 34 are all indicated by 4000).

The position of the gas sampling conduit is adjustable relative to the attachment member. For example, Figure 35 shows an attachment member/connector for a patient interface, wherein the attachment member includes a headgear clip 3550 that includes a Clamp 3551. The headgear clip connects the headgear strap to the side arm of the nasal cannula. The side arms of the nasal cannula include complementary clip receivers.

Figure 36 shows another form of attachment member/connector for a nasal cannula. A connector in the form of manifold portion 3650 can be inserted into the nasal cannula. The manifold portion is connected to the gas supply pipe at the threaded end. The opposite end is inserted into a complementary hole in the nasal cannula to supply gas to the cannula of the nasal cannula. The manifold section includes clamps 3651 for securing the gas sampling conduit.

Figure 37 shows a breathing apparatus incorporating the connector/attachment member of Figures 35 and 36 connected to a nasal cannula, and also shows the relative position of the breathing apparatus on the patient's face. Use a clamp similar to that shown in Figures 35 and 36 to connect the gas sampling conduit to the conduit.

A breathing apparatus incorporating either or both of the connectors/attachment members of Figures 35 and 36 allows a retention method for attaching the gas sampling catheter to the breathing apparatus independent of the patient's face shape and/or size.

The gas sampling catheter is usually held slightly in or near the patient's mouth, or just inside or near one of the patient's nostrils, to reduce the amount of fluid drawn into the catheter or from the catheter to the patient (eg, into the patient's cheek). or on the lips) and the chance of blockage. Positioning the catheter in this manner is less invasive and less obstructive than known sampling systems that require positioning the entrance to the gas sampling interface at the back of the patient's mouth. By positioning the catheter in or near the oral or nasal cavity, it is possible to reduce the risk of the sampling catheter creating pressure points or agitating the patient.

In one form, the gas sampling interface or conduit may be integrated with the conduit and molded or extruded to form a portion having two air lumens; one in fluid communication with the respiratory gas monitor and one with the air lumen/tube and conduit The gas flow source is in fluid communication. For example, the gas sampling interface or conduit may be partially co-extruded or co-molded with the gas delivery tube of the conduit.

In one form, the gas sampling catheter can be clipped to a breathing apparatus such as a nasal cannula. The sampling catheter can be clamped to the catheter during manufacture or provided flexibility of use by the end user. In one form, only one clamp can be used to connect the sampling catheter. Alternatively, multiple clamps may be used across at least a portion of the length of the catheter to give additional stability and positioning control of the sampling catheter relative to the catheter. The clamp can be placed on one side of the patient's face so that the other side of the face is free of the device. Alternatively, the clamps can be placed on either side of the nasal cannula of the catheter.

In one form, the nasal cannula and gas sampling catheter can be configured to connect the gas sampling catheter to the gas sampling tube of the respiratory gas monitor and simultaneously connect the catheter to the gas delivery source, and have a single connection comprising two connectors and / or with a single link movement.

As mentioned above, the sampling catheter may be a single lumen catheter. Alternatively, the sampling catheter may be a dual lumen catheter having a guide wire positioned within at least one lumen to provide positional control of the sampling catheter such that the catheter may be selectively positioned in the patient's mouth or in the patient's nose At (or near) one nostril.

Other forms of attachment members may be used to attach the gas sampling catheter to the breathing apparatus. For example, Figures 27 and 28 illustrate one embodiment of an attachment member in the form of a strap or loop 2740. The band or ring may comprise elastic or elastomeric material such as TPE or silicone. The strap or ring 2740 can stretch and slide over the conduit and gas sampling conduit. The location of the conduit is indicated by 2741 and the location of the gas sampling conduit is indicated by 2743. The catheter side of the strap 2740 may have a thinner wall portion (eg, 0.5-1 mm) to ensure it is compact and has adequate stretch on the patient's face. The catheter side of the strap 2740 may have a thicker wall portion (eg, 1.5mm-2mm) to ensure that the catheter does not stick to the strap when pulled and/or repositioned, and to ensure that the clamp does not move with the catheter. The cross-section of the band may be circular, triangular or irregular, and/or depend on the cross-section of the conduit.

29-34 illustrate embodiments of attachment members in the form of clips 2940, clips 3140, and clips 3340 that are slidable on the catheter. The location of the conduit is indicated by 2941/3141/3341, and the location of the gas sampling conduit is indicated by 2943/3143/3343. 29 and 30 show a clamp with overlapping portion 2945. Figures 31-34 illustrate a clip with tongues 3145/3340/3341 extending from the clip body to provide space for insertion and retention of a catheter therein. The tongue can be bent or bent to allow this insertion. The clamps of Figures 33 and 34 also show a curved tongue 3345 that provides a space for inserting a gas sampling catheter and retaining the catheter therein. Each tongue can be bent or bent to allow this insertion. For example, as the case may be, the gap between the tongue and the clamp body may be smaller than the outer diameter of the gas sampling conduit or the portion of the conduit to be attached to the clamp. In this arrangement, the flexible nature of the tongue allows the cannula or conduit to be pushed into the gap so that the tongue moves away from the clamp body to allow the cannula or catheter to be positioned between the clamp body and the tongue. Once the cannula or conduit is in position within the clamp, the pressure on the tongue can be removed, allowing the tongue to return to its natural resting position, without sufficient force to force the tongue away from the clamp body again , the cannula or catheter cannot be removed from the clamp. The tongue may be offset towards the clamp body. In some forms, the gap between the tongue and the clamp body may be slightly smaller than the portion of the catheter held by the clamp or smaller than the outer diameter of the catheter, so that the catheter (cannula or conduit) is gently clamped between the tongue and the clamp body between. Such embodiments may comprise polymeric materials such as polypropylene. In one form, the clamp may have a broken cross-section that allows space for the conduit to pass through. The clamp may have a fixed gas sampling conduit and may be a separate part of the clamp (eg, a partial cylinder or cylinder). The cross-sectional design may depend on the conduit cross-section.

In one embodiment, the gas sampling interface includes a hook for engaging a portion of the patient's face and an attachment system for securing the gas sampling catheter relative to the hook such that the inlet of the catheter receives the patient's exhaled and/or exhaled gas . The hook can be inserted into the patient's nostril or the patient's mouth. For example, hooks can be inserted into the corners of the patient's mouth. The hook provides a system by which the catheter is attached to the patient to position the catheter in the vicinity of the mouth or nose.

The hook may be rigid. Alternatively, the hook may be flexible. In further alternatives, the hooks may be a combination of rigid and flexible materials or features. Rigid or flexible hooks may be molded polymeric materials.

The hook may include any suitable attachment system including, for example, at least one connecting member (eg, a channel, clamp, pair of clamps, or straps) that secures the gas sampling conduit to the hook. The attachment member may comprise an elastomeric material.

The attachment member may be integral with the hook or with a separate element to the hook. The position of the gas sampling conduit can be adjusted relative to the hook.

The following alternative embodiments of the gas sampling interface include rigid hooks that can be supplied in different sizes based on patient anthropometric considerations.

Referring to the embodiment shown in Figure 38, the gas sampling interface includes rigid hooks 3860 for supporting the gas sampling conduit. Figure 38 shows an embodiment of a hook with a narrow area. The shape of the hook is similar to the shape of the spine shown and described in FIG. 3 . The narrow area advantageously provides some compression of the patient's cheek to hold the hook in place. In the embodiment of Figure 38, the narrow area is approximately 8 mm.

The radius of the hook tip defines the minimum radius of curvature of the gas sampling catheter, thus preventing kinking of the catheter and providing clearance around the thicker area of the patient's cheek (facial worm axis) near the patient's mouth.

An angled or curved portion is provided on the outside of the mouth, where the hook is shaped away from the cheek to allow easy hook attachment and removal.

The following embodiments of the gas sampling interface incorporate a gas sampling conduit that includes a flexible elastic support structure (eg, a wire). The wire may be a wire or rod positioned in the lumen of the gas sampling catheter, integrated into the material of the gas sampling catheter (overmolded or co-molded), or otherwise attached or bonded to the exterior of the gas sampling catheter. This allows for positional adjustment of the free end of the catheter. Alternatively, the hook may be semi-rigid, but still malleable, so that no wire is required.

In some forms, the gas sampling conduit can slide along the hook to vary the length of the free end of the conduit that can extend beyond the free end of the hook. In another form, the catheter may be connected to the hook such that the free end portion of the catheter is at the desired length. When combined with the ability to move the gas sampling catheter relative to the hook, the gas sampling catheter end position is limited only by the length of the catheter tubing, the length of wires within the catheter, and physical limitations imposed by the patient or necessary surgical or procedural equipment .

38-46 illustrate embodiments of rigid and semi-rigid hooks with different features and/or methods of attaching gas sampling catheters to rigid or semi-rigid hooks.

The embodiment shown in Figures 38-40 includes a connecting member with an integral clip 3861 on the outside of the rigid hook. The clamp 3861 allows the sampling conduit 3863 to be pressed into the clamp via a curved clamp or a curved gas sampling conduit or both. The clamp also allows the sampling conduit to be pulled or pushed axially through the clamp to adjust the length of the free end portion of the gas sampling conduit. Once adjusted, the clamp holds the sampling catheter in place relative to the hook.

FIGS. 41 and 42 illustrate a hook with a catheter attachment system having attachment members including a clip 4167 integral with the interior channel 4165 of the hook 4160. This embodiment allows the gas sampling conduit 4163 to be pressed into the clamp via a curved clamp or curved gas sampling conduit. This embodiment also allows the gas sampling conduit 4163 to be pulled or pushed axially through the clamp 4167 and channel 4165 so that the free length of the tube can be adjusted. Furthermore, this embodiment maintains the gas sampling conduit 4163 in a fixed position relative to the hook 4160.

43 shows a perspective view of an alternative embodiment of a rigid hook of a gas sampling interface 4360. This embodiment incorporates a rigid end stop for positioning and constraining the flexible element used to attach the sampling tube to the rigid hook.

Figure 44 shows an embodiment with the rigid hook of Figure 43 and a flexible element 4469 forming a sleeve for holding the gas sampling conduit 4463 while allowing adjustment of the length of the free end portion of the gas sampling conduit. The sleeve may be ribbed to provide additional grip on the outside of the patient's cheek.

Figures 45 and 46 show embodiments of hooks with attachment systems that have been overmolded on the hooks. These embodiments include rigid polymer hooks 4560 and one or more overmolded sleeves each forming an attachment member. The gas sampling conduit is passed through the cannula(s) to attach the gas sampling conduit 4563 to the hook. The length of the free end portion of the gas sampling conduit can be adjusted by pulling the conduit through the sleeve/overmold material until the desired length extends beyond the sleeve. That is, the sleeve/overmolded portion or element is secured to the rigid hook by mechanical and/or chemical locking, but not to the gas sampling conduit. These embodiments may incorporate curved ridges and other features such as soft handles.

As mentioned above, the hook may be flexible. Flexible pre-formed hooks are inserted into the corners of the patient's mouth and provide an attachment for securing the gas sampling catheter to the vicinity of the patient's mouth or nose. One advantage of a flexible hook is that the shape of the hook can be changed, eg, by bending, to accommodate the size of the patient's mouth.

The embodiments shown in Figures 47 and 48 incorporate wires in the form of flexible wires, rods or bars (metal or polymer) overmolded with a suitable flexible polymer (in a flat position) Or co-molded and then the hooks are formed before dispatch to the customer; the suitable flexible polymer such as TPE or silicone. This embodiment includes attachment members including clamps 4761 for external attachment of gas sampling conduits 4763. In this embodiment, the overmold material is bonded to a wire such as an internal flexible wire, rod or tape (metal or polymer) to allow for easy modification of hook size and shape to suit individual patients. The overmolded design includes one or more connecting members (clamps) for connecting to the gas sampling conduit. The overmolded design may include features for bend release in place to allow the overmolded wire to be bent into a hook shape. In this embodiment, there may be bend relief features in the mold for wire positioning. Hooks can be pre-formed prior to dispatch.

Referring to Figures 49-53, an alternate embodiment of an attachment member having dual flexible tubes or sleeves for attachment to two tubular members is shown. The tubular member may include a gas delivery conduit and a gas sampling conduit, or the tube may include a gas sampling lumen and a support lumen, or the tube may include, for example, a pair of gas sampling lumens. In these embodiments, the gas sampling interface may combine a gas sampling catheter with a wire, such as a wire, or rod, or tape located in a lumen of the wire, which is integrated (eg, by overmolding or co-molding). ) into the tube material of the catheter or adhered or bonded to the exterior of the catheter. The gas sampling conduit is preferably shaped as a hook for attachment to the patient's mouth. Such embodiments also include gas sampling conduits having wires (eg, metal wires, or rods, or tapes) located in one of two or more lumens within the gas sampling conduit. The wire may be integrated (eg, by overmolding or co-molding) into the tube material of the catheter or adhered or bonded to the outside of the tube to allow the catheter to be oriented by providing a semi-flexible and resilient end to the catheter. Positioned, the semi-flexible and resilient end can be bent into a desired shape to engage the patient's mouth or nostrils during gas sampling.

Engagement of the two catheters can be via one or more connecting members including a clamp with limited or no movement relative to the hook catheter (4973/5073/5173) while allowing axial movement of the sampling catheter Pass through the clamp (4971/5071/5171) so that the free length of the catheter can be adjusted. Multiple fixtures may be required. 49-51 show various embodiments of clamps 4970/5070/5170. The clamp can be a molded or extruded element. FIG. 52 shows the gas sampling conduit 5263 attached by the clamp 5270 to the hook 5260.

Figure 53 shows a clamp 5270 molded around a pair of lumens of a dual lumen catheter. The clamp 5270 can be overmolded on and or co-molded with the cavity. This form of clamp maintains lumens that are substantially equidistant from each other, but also allows the lumen of the catheter to be pulled or pushed axially through the overmolded or co-molded material of the clamp so that the free length of the catheter can be adjusted. Multiple overmolded or co-molded clamps can be used along the length of the catheter.

Figure 54 shows a cross section of a pull cord catheter with a first tether for gas sampling and a second tether configured to form a hook shape. The cord of the catheter can be unwound and cut so that the second cord shape can be designed to form a hook that is substantially shorter than the first cord used for gas sampling. The gas sampling cord may also be formed into a suitable hook shape to best sample the patient's breath or exhaled breath. Figure 54 shows a gas sampling catheter comprising a first pull cord having a gas sampling lumen 5481 and a wire lumen 5483, and a second pull cord having a second wire lumen 5485 for forming a hook shape.

In one embodiment, as shown in Figure 55, the gas sampling interface includes a gas sampling conduit 6163 and an attachment member 6140 to secure the gas sampling conduit to a breathing apparatus 1000 (eg, a mask or nasal cannula) that delivers breathing gas to a patient. 8040). In one form, the gas sampling conduit is removably attached to the attachment member. The attachment member may be configured to be removably connected to the breathing apparatus, or the attachment member may be integral with (form a part of) the breathing apparatus. For example, the attachment member may be built into the design of a nasal cannula, mask, or other breathing device to removably attach the gas sampling catheter to the breathing device.

In one embodiment, as shown in FIGS. 55-57 , the attachment member 6140 includes a body 6141 attachable to the breathing apparatus 1000 . The body 6141 can be clamped to a portion of the breathing apparatus. In one form, the body 6141 of the attachment member 6140 may form a substantially or partially closed sleeve that encloses a portion of the breathing apparatus 1000.

As shown in Figures 55-57, with the sleeve partially closed, the body/sleeve 6141 includes a pair of spaced apart protruding resilient arms 6150. Each protruding arm terminates in a side edge 6144. The sleeve 6141 includes an inner region 6142 and an opening 6143 to the inner region 6142 . The arms 6150 can be bent towards each other such that the area between the body 6141 and the protruding arms 6150 forms the inner area 6142 of the sleeve. Openings 6143 are defined by the arms and side edges 6144 of the sleeve and extend along the length of the sleeve. The inner region 6142 is defined by the inner surface of the attachment member and is shaped and dimensioned to receive a portion of the breathing apparatus 1000 (eg, a portion of a nasal cannula). The arms 6150 can be configured to be biased toward each other, but can be flexible enough to be pushed apart, eg, by pushing a portion of the breathing apparatus 1000 between the arms 6150. The material and dimensions of the sleeve-like body 6141 can be such that at least a portion of the breathing apparatus is retained within the interior region 6142 of the sleeve 6141, eg, by the arms 6150 clipped to the breathing apparatus. Other forms of attachment may also be suitable. Typically, the attachment member 6140 is configured to attach to the air delivery tube 8060 of the breathing apparatus 1000, although it is contemplated that the attachment member may be configured to attach to another portion of the breathing apparatus, such as a headgear of the breathing apparatus . For example, if the breathing apparatus includes a nasal cannula 8040, the attachment member may be configured to attach to the air delivery tube 8060, the manifold 8070 of the catheter, the side arms 8080 of the catheter, or the headgear 8090 of the catheter.

In the embodiment shown in FIGS. 55-57, the body 6141 of the attachment member 6140 is configured to attach to a substantially curved portion of a breathing apparatus (eg, breathing gas delivery tube 8060). In this form, the attachment member 6140 includes a substantially curved sleeve having curved arms 6150 or arms that include at least a curved inner surface (as shown) such that the arms are configured to clip Tightly or at least partially wrap the outer curved surface of the breathing gas delivery tube. In other words, the shape of the inner region 6142 is designed to substantially correspond to the outer contour of the gas delivery tube 8060 of the nasal cannula. For example, the inner region 6142 of the sleeve can be substantially curved to provide a substantially arcuate inner surface to the inner region and a substantially C-shaped cross-section to the sleeve such that the sleeve can at least partially wrap the gas delivery tube A portion of 8060 or other suitable curvature of a breathing apparatus, such as the curvature of the manifold of a nasal cannula. In another form, the cannula may form a substantially U-shaped cross-section to at least partially enclose a portion of the gas delivery tube 8060 or other suitable curved portion of the breathing apparatus, such as a curved manifold. In another form, the at least substantially arcuate inner surface of the sleeve may be formed by a plurality of substantially flat regions/surfaces arranged in series to form a substantially closed or fully closed sleeve. Where the sleeve is substantially closed, the substantially flat surfaces may be arranged to form a sleeve with a substantially C-shaped cross-section or to form a sleeve with a substantially U-shaped cross-section. In any form, at least the inner surface of the sleeve can be shaped to substantially match the outer shape of the portion of the breathing apparatus to which the sleeve is to be attached. For example, if the sleeve is to be attached to the side arm of a nasal cannula having a substantially thin rectangular profile, the inner surface of the sleeve may be formed from three substantially flat areas connected at right angles to provide substantially Sleeve with angular U-shaped profile.

The sleeve may be formed from a substantially flexible elastic material, such as a metal or polymeric material, that allows the cannula to return substantially to or toward the original resting position when the cannula is pushed over a portion of the nasal cannula , the spaced side edges 6144 or arms between the sleeves are biased and spaced toward each other in the rest position. Generally speaking, the width of the opening between the side edges 6144 is smaller than the diameter of the portion of the gas delivery tube 8060 (or other portion of the breathing apparatus) held within the cannula so that the breathing apparatus is securely held within the casing.

In one embodiment, the inner surface of the sleeve 6141 may include a plurality of ribs to engage or interlock with ribbed formations on the outer surface of the corrugated breathing gas delivery tube 8060. In one embodiment, the attachment member 6140 is removably connected to one of the side arms 8080 of the nasal cannula 8040 (or the side arm of the mask) by any suitable connection form. For example, the attachment member 6140 can include a pair of spaced apart protruding arms 6150 that are offset toward each other and configured to mate on opposing side surfaces of the side arms of the sleeve or mask to attach the attachment member Clamp to side arm. To mate the attachment member 6140 to the side arm, the attachment member 6140 can be positioned such that the side edge of the side arm is located at the opening between the protruding arms 6150 of the attachment member 6140. The arms 6150 are then separated by sliding the protruding arms 6150 of the sleeve 6141 onto opposing front and rear surfaces of the side arms to push the attachment member onto the side arms. The biased nature of the arm 6150 causes the arm 6150 to grip the side arm.

In another form, the attachment member may include a hinged clasp including a pair of arms attached together at closed hinged ends and including opposing receiving ends configured to utilize The hinge is opened or closed by moving the arms of the clasp towards and away from each other to close and open the hinge. The receiving end of the clasp may include a locking system configured to releasably lock the two arms of the clasp together. Any suitable locking system may suffice, such as a hook or post on one arm of the clasp that is configured to engage with a hook or hole on the other arm of the clasp. To mate the attachment member to the side arm, the receiving end of the clasp is opened to allow one arm of the clasp to slide under the side arm of the nasal cannula or mask. The other arm is then placed on top of the side arm and locked to the lower arm to clamp on the side arm and hold the hinged clasp in place. Where the attachment member forms a clip, the arms or gripping members of the clip may be shaped to be substantially complementary to the shape of the side arms to maximize grip retention on the side arms (preferably, to maximize patient comfort).

In one embodiment, the body or sleeve 6141 of the attachment member 6140 includes at least two offset clamps 6167 (a first clamp and a second clamp) attachable to the gas sampling conduit 6163 . The biasing clamp may be located on the outer surface of the attachment member. The offset arrangement of the clamp 6167 causes the gas sampling conduit 6163 to follow a tortuous path when attached. This helps keep the sampling catheter 6163 in place and reduces the risk that the sampling catheter may be accidentally pulled out of the patient's oral or nasal cavity or pushed too far into the patient's oral or nasal cavity.

Each clamp 6167 includes a tube receiving area 6170 within which a portion of the gas sampling conduit 6163 can be retained.

In one embodiment, each clamp 6167 forms a hook that includes an arm 6168 extending from the clamp body 6141 and terminating at a distal end 6169 a distance away from the outer surface of the connecting member body 6141 . The space between the distal end 6169 of the clip and the outer surface of the attachment member 6140 forms the clip opening. Arm 6168 may be curved. For example, the arms 6168 may include an inner surface that forms a substantially curved or concave tube receiving area 6170. The size of the curved profile of the tube receiving area 6170 may substantially correspond to the curved outer profile of the gas sampling conduit 6163 . In one form, the diameter of the curved tube receiving region 6170 may be at least as large as the diameter of the gas sampling conduit tube 6163. In another form, the diameter of the curved tube receiving area 6170 may be slightly smaller than the diameter of the gas sampling conduit to press against the gas sampling conduit and help maintain the position of the gas sampling conduit within the clamp 6167. In one form, the hook clamps may face in the opposite direction. For example, the first hook may face one side of the gas delivery tube (when on the tube) and the second hook may face the opposite side.

To assemble the gas sampling conduit 6163 to the attachment member 6140, the conduit 6163 is pushed through the opening of one clamp 6167 and then through the opening of the other clamp 6167 to follow a tortuous path that holds the conduit in place within the clamp. The length of the free end portion of the catheter can be easily adjusted by hooking/removing the catheter from the first clamp and then pulling the catheter in the desired direction so that the catheter slides through the second clamp until the free end portion is at the desired length. The catheter can then be hooked into the first clamp again to secure the catheter in place.

The gas sampling conduit 6163 can be removably mounted within the clamp 6167 of the attachment member 6140 so that the conduit can be replaced if desired. Thus, the gas sampling conduit can be removed from the attachment member by pulling the sampling conduit out of the clamp opening. Alternatively, the gas sampling conduit may be held permanently in the attachment member.

Each clamp 6167 is typically formed from a flexible elastic material that substantially returns upon pushing the gas sampling conduit 6163 into the tube receiving area 6170 and back once the gas sampling conduit 6163 is positioned within the tube receiving area 6170 In the original state, at least a portion of the hook is allowed to move away from the main body 6141 . In this embodiment, the distance between the distal portion of each hooked arm 6168 and the body 6141 (clamp opening) may be less than the diameter of the gas sampling conduit 6163 to help prevent the gas sampling conduit 6163 from inadvertently disengaging from the clamp 6167.

Depending on the shape and size of the tube receiving area 6170 and the gas sampling conduit 6163 in each clamp 6167, the clamp 6167 can be configured to loosely hold the gas sampling conduit 6163 in place within the clamp 6167 or securely hold the conduit 6163 in place. appropriate location.

In one embodiment, each clamp 6167 can be configured to clamp onto at least a portion of the gas sampling conduit 6163 with sufficient force to attach the conduit 6163 to the clamp 6167 without blocking the flow of gas within the sampling conduit 6163 path.

A connection or attachment member 8050 (such as a luer connector as shown in FIGS. 65-67 ) may be provided at or near the outlet 109 of the gas sampling conduit 101 of the gas sampling interface 100 to fluidly connect the sampling conduit 101 and the interface 100 Connect to the gas sampling line of the breathing gas monitor. It will be appreciated that any other means of connection between the interface and the gas sampling tube may alternatively be employed. In another form, the outlet of the gas sampling conduit may be directly connected to the inlet of the respiratory gas monitor.

As mentioned above, the use of a flexible elastic sampling catheter with a support structure (such as a wire) and the use of an attachment member to attach the catheter to the breathing apparatus, a catheter that allows the length of the free end portion to be adjusted, is a particularly advantageous embodiment, As shown in Figures 70 and 71, the catheter (and thus the sampling interface) can be selectively positioned (elastically bendable/shapeable) for placement near the mouth or nose. The distal end of the sampling interface can be placed in the mouth at approximately the location of the teeth, near the mouth, or near the patient's nostrils or nostrils. If a nasal cannula is used as a breathing device, it may be difficult to fit both the cannula of the cannula and the sampling interface into the patient's nostril, but depending on the size of the end portion or head of the sampling interface and how the patient is anesthetized, sampling Both the interface and the catheter cannula can be inserted into the nostrils. Alternatively, the sampling interface may be located just outside the nostril. Thus, the versatility of the sampling interface means that it can be used for patients exhaling and/or exhaling air through the mouth or nose (or, for dyspnea patients, and for patients whose breathing air is primarily from the body or only through the mouth or nose). The interface can simply be repositioned to suit the patient as needed. The interface can also be repositioned to suit the needs of the clinician and the limitations of the medical procedure. For example, during surgery, the patient's mouth may be held open multiple times by other medical devices or equipment, which may allow a good breath trail of exhaled and/or exhaled breaths via the gas sampling interfaces/devices disclosed herein to be Picked up from the patient's mouth. Alternatively, if the patient's mouth is closed, the sampling interface can be easily moved near the nostrils, or the distal end or head of the sampling interface can be positioned between the patient's lips (eg, against their teeth). It has been found that tracing exhaled and/or exhaled breaths from the patient's mouth is particularly effective when the patient is receiving high flow therapy via a nasal cannula. This is because placing the sampling interface at the mouth allows traces to be found (since the resistance to the flow of gas entering the sampling interface through the mouth is generally less than the resistance created by the high flow of breathing gas provided to the nostrils).

Figures 58-64 illustrate further embodiments of a gas sampling head 7050 that can be connected to a gas sampling conduit to receive gas expelled from a patient. The sampling head 7050 may be integrally formed with the gas sampling conduit 6163 or separately and then attached to the free end/gas inlet end of the sampling conduit 6163. The sampling heads 7050 may each be connected to the free ends 6163 of the sampling conduits using any suitable form of attachment. For example, the sampling tip can be welded to the sampling conduit; screwed onto the threaded free end of the sampling conduit; glued or otherwise adhered to the free end of the sampling conduit; or the sampling head and sampling conduit can be arranged in a hook-fit and friction-fit arrangement etc. attached together.

In a preferred embodiment, the gas sampling head 7050 is formed from a soft or semi-soft compressible material. Sampling heads made of rigid or hard materials may cause injury to the patient or may damage the patient's teeth (especially if the head is placed between the teeth and the patient inadvertently bites the head). These risks are avoided or at least mitigated by providing a sampling head that can contain compressible materials that are less likely to cause injury or harm to the patient.

In one embodiment, the sampling head 7050 includes a body 7060 that includes a substantially hollow interior region 7061 configured to communicate with the gas sampling conduit when the sampling head 7050 is connected to the sampling conduit 6163. The inlet of 6163 is in fluid communication. The body 7060 includes one or more sidewalls forming an outside surface of the body, a proximal connection end 7062 for connecting to the free end of the gas sampling conduit to place the hollow interior region in fluid communication with the gas sampling conduit, and a distal end terminating in the sampling head 7050. The distal portion 7063 of the end 7064.

In one form, the connection end 7062 may be glued to the gas sampling conduit 6163. In another form, the connection end 7062 can be threaded to the threaded end of the gas sampling conduit 6163 so that the sampling head can be tightened and unscrewed on the free end of the sampling conduit. In another form, the connection end may include a lip configured to fit over the collar of the inlet end of the sampling conduit to connect the sampling head and conduit in a snap-fit arrangement. Alternatively, the inlet end of the sampling conduit may include a lip that fits over the collar of the connection end to the sampling head.

Sampling head 7050 includes at least one inlet/gas receiving aperture 7230. Patient exhaled or exhaled gas may be received by an inlet/gas receiving aperture 7230 in fluid communication with a substantially hollow interior region 7061 of the body 7060 such that the received gas may pass through the body 7060 of the sampling head and into the inlet of the gas sampling conduit. Each inlet/gas receiving hole forms an opening to the hollow interior region of the head body.

In one form, the gas receiving hole 7230 can extend from the distal end 7064 of the sampling head and along one side of the sampling head body 7060. Preferably, the gas receiving hole 7230 forms an elongated opening in the distal end portion 7063 of the gas sampling head.

In one form, the sampling head 7050 includes an end wall at its distal end 7064 and one or more gas receiving holes on one or more side walls of the sampling head. In one form, the gas receiving apertures 7230 may extend substantially around the entire outer circumference of the sampling head (eg, around the entire outer circumference of the outside surface). Where the sampling head has a generally round/circular cross-section, the gas receiving holes 7230 may extend around the peripheral outer surface of the sampling head to form an annular annular hole (as shown in Figures 68A-68C ) . In another form, the gas receiving holes 7230 may extend around the circumferential outer surface of the sampling head in a substantially helical arrangement (similar to the helical threads of a corkscrew).

The end wall may be substantially transverse to and offset from the gas receiving hole(s). In one form, the end wall may be longitudinally offset a distance equal to or greater than the width of the gas inlet(s).

The cross-sectional area of the end wall may be less than, substantially equal to, or greater than the cross-sectional area of the hollow interior region of the sampling head body.

In one form, the cross-section of the end wall is the same as or greater than the cross-section of the gas receiving hole(s)/inlet(s).

In some embodiments, as shown in FIGS. 58-66 , the gas sampling head 7050 can include a plurality of inlet/gas receiving holes 7230 . For example, the sampling head 7050 may include a pair of gas receiving holes 7230 extending from the distal end of the sampling head and along the sides of the distal end portion 7063 of the gas sampling head body 7060. The holes 7230 may be evenly spaced from each other or may be unevenly spaced from each other. For example, the holes 7230 can be located on substantially opposite sides of the body 7060, or the holes 7230 can be closer to each other in at least one direction. In other embodiments, the gas sampling head 7050 may include two, three, four, or more gas receiving holes 7230 . The holes 7230 may or may not be evenly spaced from each other.

In the embodiment shown in FIGS. 58-66 , the gas sampling head 7050 includes three gas receiving holes 7230 evenly spaced around the distal end and sides of the sampling head 7050 . The spacing of the holes 7230 can be best seen in FIGS. 58 , 59 , 61 and 63 .

Each portion of the sampling head body 7060 located between the gas receiving holes 7230 forms a groove 7240 terminating at the distal end of the sampling head 7050 . A central support 7250 can be located at the distal end of the sampling head 7050 and can be connected to the groove 7240. The central support 7250 provides additional strength and positional integrity to the grooves 6240 to prevent the grooves 7240 from pressing together and at least partially blocking the gas receiving holes 7230. The central support 7250, the groove 7240, and the body 7060 of the sampling head 7050 together define the edge of the gas receiving hole 7230.

The body 7060 of the gas sampling head 7050 can have a substantially cylindrical form, and the grooves 7240 can be substantially evenly spaced around the circumference of the distal portion 7063 of the gas sampling head 7050. In one form, the interior of each groove may include a cutout area to form an enlarged opening in the head.

In one form, as shown in FIGS. 68A-68C , the distal end 7064 of the sampling head may be supported by a support member including a stem/strut/arm/elongate extension 7070 connected to the end wall and body 7060 . The support member 7070 can be positioned substantially centrally along the longitudinal axis of the sampling head, or the support member can be generally laterally offset from the center of the longitudinal axis of the sampling head. For example, the support member 7070 may be attached to at least one inner wall of the body or an outer side surface of the body of the sampling head. In one form, as shown in Figure 68C, the body 7060 of the sampling head can form a plug with a protruding support member 7070 that includes a strut connected to the distal end 7064 of the sampling head. The plug body 7060 can be configured to be positioned within a lumen or auxiliary channel in the gas sampling conduit 201 to attach the head to the conduit without blocking the gas receiving inlet of the sampling conduit. For example, the auxiliary channel may be the first support lumen 211 of the gas sampling conduit 201 (the conduit shown in Figure 2). The support members/struts may be offset from the body of the head 7060 and/or offset from the longitudinal centerline of the gas sampling conduit 201 (as shown in Figures 68A-68C). This arrangement is particularly advantageous where the body of the head is configured to engage with a biasing body that receives a cavity or hole located near and to one side of the inlet of the gas sampling conduit.

In another form, the sampling head body 7060 can be configured to be received within an inlet at the distal end of the gas sampling conduit. In this form, the sampling head includes a body 7060 that is shaped and dimensioned to be received within the gas inlet of the sampling conduit. A support member 7070 including a stem/strut/arm/elongate extension etc. protrudes from the body 7060 and is connected to the distal end portion 7064 of the sampling head 7050 to maintain the distal end portion 7064 at a distance from the body 7060. For example, support members or struts 7070 may protrude from the upper surface of the sampling head body 7060. The support members/struts 7070 may protrude substantially centrally from the upper surface of the body 7060, or the struts 7070 may be offset from the center of the body 7060. Post 7070 and distal portion 7064 of sampling head 7050 can be configured such that distal portion 7064 cantilevers from post 7070 or at least extends beyond the circumference of post 7070. The arrangement of the distal portion and the support member forms a shield over the inlet(s)/gas receiving aperture(s) of the gas sampling head. Because the sampling head body 7060 is placed within the gas inlet of the gas sampling chamber, in a plug-in arrangement, at least one gas receiving hole 7230 is formed in the sampling head 7050 to allow for the passage of gas through the gas receiving hole 7230 and through the head. Hollow body 7060 and enter a gas sampling conduit to pass gas through sampling head 7050. In one form, at least one gas receiving hole 7230 is formed in the upper surface of the body 7060 and is in fluid communication with a substantially hollow interior 7061 of the body that opens at its proximal end to create fluid flow with a gas sampling conduit path (shown in Figures 69A-69C). In another form, the at least one gas receiving hole 7230 can be formed in the support member/strut 7070, and the support member/strut 7070 can include a substantially hollow body in fluid communication with the gas receiving hole 7230 and the base of the sampling head body 7060 The upper hollow interior allows gas to flow through the gas receiving hole(s) 7230, through the hollow body 7060 and into the gas sampling conduit.

In another form, the support member/strut 7070 can extend from at least one side wall of the gas sampling conduit 7060 such that the distal end 7064 cantilevered from the strut 7070 . For example, the support members/struts 7070 can extend from the body (such that the outer surface of the body extends along the outer surface of the strut), and can be cantilevered distally from the strut. In one form, the end wall is integrally formed with the body 7060.

In one form, as shown in Figures 68A-69C, the distal end portion 7064 of the sampling head may include a curved or dome-shaped end wall 7064a that forms a shroud to protect the inlet(s) of the gas sampling head / The gas receiving hole(s) are drawn by the patient's cheeks, mouth, lips or nostrils. The end walls also advantageously prevent direct entry of saliva into the hollow interior region of the body (especially from the longitudinal direction). This is very important to prevent clogging of the sampling head and gas sampling conduit.

In the embodiment shown in FIG. 61 , the distal end 7064 of the gas sampling head 7050 (including the distal end of the central support and groove) is bent or convex outwardly to form a protruding cover that prevents the gas receiving hole 7230 from leaking. The distal opening is suctioned from the patient's cheek, mouth, lips, or nostril. The side surfaces of the grooves 7240 at the distal portion of the sampling head 7050 may also be curved outward to form a substantially spherical distal end.

The sampling head and/or sampling tube and/or attachment member may be a single use product for a single occasion by a single patient, or may be configured to reduce any risk of infection by being suitable for cleaning using a sterilization process or autoclaving material to be reused.

Any of the embodiments described herein may be used in combination with a respiratory device (eg, a nasal cannula) to position a sampling interface on a patient. A nasal cannula may provide high flow of breathing gas to a patient's airway via a nasal cannula. The gas is generally oxygen or an air/oxygen mixture. The gas is humidified by a humidifier before being delivered to the patient. The high flow of gas causes turbulence and flushes the pharynx and pushes oxygen/breathing gas into the patient's airway. The catheter continuously supplies gas to the patient's upper airway. The gas sampling interface is used to sample the patient's breath and/or breath. The multifunctional nature of the interface allows the interface to be selectively remote from the gas supply so that gas sampling measurements are not diluted as much as gas sampling and gas delivery occur at the same physical location in/on the patient.

The interface may be mounted to or engage with a portion of the user's face, eg, the cheeks, lips, or nostrils. The interface includes a hooked free end portion or can be manipulated to provide a hooked portion (as in Figures 1-6, 9-26, 37-48, 52-55, 70 and 71 ). In the case of the embodiment shown), the interface can be hooked around a portion of the patient's face (eg, around the mouth or nostrils) to engage the patient's face and position the interface adjacent the patient's airway.

The sampling interface can be attached (eg, clipped) to a portion of the catheter/breathing device to maintain the gas sampling interface in the operative position. For example, a breathing device or nasal cannula may optionally be used as a mounting element for attaching a sampling interface to the breathing device rather than gluing the interface to the patient's face. Alternatively, the interface may be attached to the breathing apparatus using any of the embodiments of attachment members shown in FIGS. 26-37 and 49-57 suitable for attachment to the breathing apparatus.

Combining a gas sampling interface with a breathing apparatus in the form of a nasal cannula reduces the need for additional headgear or straps, etc. Additionally, attaching or clipping the gas sampling interface to the nasal cannula reduces the force on the user's cheeks or nostrils.

It will be further understood that any combination of embodiments of the header structure may also be used in any of the embodiments described herein. For example, the gas sampling interface may include any of the embodiments of the gas sampling heads shown in Figures 4-8, 14-25, 55, 58-66, and 68A-71.

The nasal cannula and expiratory and/or exhaled gas sampling interface can be used with both dyspnea patients and spontaneously breathing patients. Since the dyspnea patient is not actively exhaling, not much _CO2 , if any, is expelled from the patient. Furthermore, low flow breathing gas delivery systems do not model the turbulence required to flush _CO2 from the physiological dead space in the lungs of dyspnea patients, which again means that not much _CO2 is expelled from the patient. In addition, the small amount of _CO2 emitted will be diluted by the gas flow from the breathing apparatus/gas delivery system. This dilution makes it more difficult to _discern whether or how much _CO is leaving the patient's lungs. In cases of dyspnea, _CO2 usually cannot be detected in the nose or mouth because there is no patient ventilation to expel the _CO2 from a distance. It has been found that the vortex created in the lungs by high flow breathing therapy can flush _CO2 from the lungs to the nose and/or mouth to potentially allow breath/gas sampling. Oscillatory high-flow therapy amplifies this response, making it more likely to detect CO ₂ in the nose or mouth. It has been found that combining psychogenic oscillations with high flow breathing therapy allows a certain amount of ventilation where the breathing gas moves with the patient's heartbeat and is expelled by the psychogenic pulse. The gas sampling interface of the present invention is particularly suitable for measuring exhaled and/or exhaled gas in dyspnea patients, especially when used with respiratory gas monitors of sufficiently low resolution and/or using specific algorithms to When dealing with very low amounts of _CO2 (perhaps at least as low as one tenth of the normal range or less). Therefore, the gas sampling interface of the present invention can be used to determine whether the airway of a dyspnea patient is open, whether high-flow breathing therapy is in operation, and to measure the level of _CO2 exhaled by the patient (exhale or expell).

The foregoing description of the invention includes its preferred forms. Modifications may be made without departing from the scope of the present invention.

As used in this specification, the term "comprising" means "consisting at least in part". In interpreting each statement in this specification that includes the term "comprising", features in addition to or preceding the term may also be present. Related terms such as "comprising" should be interpreted in the same manner.

Wherein, in the preceding description, reference has been made to integers or elements having known equivalents thereof, which integers or elements are incorporated herein as if individually set forth.

The disclosed methods, apparatus, and systems may also be broadly defined to include two or more of the parts, elements, or features mentioned or indicated in this application in any or all combinations of such parts, elements, and features ( individually or collectively).

Unless otherwise indicated herein, the recitation of ranges herein is merely intended as shorthand for referring individually to each individual sub-range or value falling within the range, and each individual sub-range or value is incorporated into the specification (with respect to as if it were recounted separately in this article).

Reference in this specification to any prior art is not and should not be construed as an admission (or any form of implication) that the prior art forms part of the common general knowledge in the field of effort in any country in the world.

Certain features, aspects, and advantages of some configurations of the present application have been described with reference to the use of a gas humidification system with a respiratory therapy system. However, certain features, aspects and advantages of the use of the gas humidification system described may be advantageously used with other therapeutic or non-therapeutic systems requiring gas humidification. Certain features, aspects, and advantages of the methods and apparatus of the present application are equally applicable to other systems.

While this application has been described in terms of certain embodiments, other embodiments that are apparent to those of ordinary skill in the art are also within the scope of this application. Accordingly, various changes and modifications can be made without departing from the spirit and scope of the present application. For example, various elements may be repositioned as desired. Furthermore, not all features, aspects and advantages are required to practice the present application. Accordingly, the scope of this application is limited only by the scope of the subsequent claims.

100: Gas sampling interface 101: Gas sampling conduit 103: Subject 105: Hook part 107: Entrance 108: Remote 109: Export 200: Gas sampling interface 201: Catheter 202: Second air chamber 203: Catheter body 204: first cavity 210: Wire 315: Protruding hook part 317: Substantially concave part 319: Substantially concave part 321: protruding curved part 403: Subject 407: Mouth 408: Entrance 607: Ripple Waveform 608: Head 701: Catheter 708: Head 723: Entrance/Opening 823: round opening 900: Double Lumen Catheter 911: Cavity 913: Cavity 1000: Breathing Equipment 1200: Double Lumen Catheter 1211: First wire/support lumen 1213: Second air chamber 1427: Entrance/Opening 1529: Hood 1629: Hood 1630: Internal Ribs 1729: Hood 1829: Hood 1830: Stopper 1929: Hood 2029: Square Hood 2032: Cut 2129:square:shaped hood 2132: Cutout 2229: Toothed element 2329: Bending Parts 2429: Hood 2740: Belt or Ring 2741: Location of the catheter 2743: Location of Gas Sampling Conduit 2940: Fixtures 2941: Location of the catheter 2943: Location of the catheter 2945: Overlap 3140: Fixtures 3141: Location of catheter 3143: Location of catheter 3145: Tongue 3340: Fixtures 3341: Location of catheter 3343: Location of catheter 3345: Tongue 3550: headband clip 3551: Fixtures 3650: Manifold Section 3651: Fixtures 3860: Rigid Hook 3861: Fixtures 3863: Sampling catheter 4000: Manifold or headgear strap 4160: Hook 4163: Gas Sampling Conduit 4165: Internal channel 4167: Fixtures 4360: Gas Sampling Interface 4463: Gas Sampling Conduit 4469: Flexible element 4560: Rigid Polymer Hook 4563: Gas Sampling Conduit 4761: Fixtures 4763: Gas Sampling Conduit 4970: Fixtures 4971: Fixtures 4973: Hooked catheter 5070: Fixtures 5071: Fixtures 5073: Hooked catheter 5170: Fixtures 5171: Fixtures 5173: Hooked catheter 5260: Hook 5263: Gas Sampling Conduit 5270: Fixtures 5481: Gas Sampling Chamber 5483: Wire cavity 5485: Second wire cavity 6140: Attachment member 6141: Subject 6142: Internal area 6143: Opening 6144: Side Edge 6150: Arm 6163: Gas Sampling Conduit 6167: Fixture 6168: Arm 6169: Remote 6170: Tube Receiving Area 7050: Sampling head 7060: Subject 7061: Internal area 7062: Connection end 7063: Distal part 7064: Remote 7064a: End Wall 7070: Support member 7230: Inlet/Gas Receiving Port 7240: Groove 8040: Nasal Cannula 8050: Attachment member 8060: Air Delivery Tube 8070: Manifold 8080: Side Arm 8090: Headband

Specific embodiments of the present invention and modifications thereof will become apparent to those of ordinary skill in the art from the detailed description herein with reference to the following drawings, in which:

Figure 1 shows an embodiment of a gas sampling interface.

Figure 2 shows an alternative embodiment of a gas sampling interface.

Figure 3 shows a spline curve representing a series of curves applied to conduits of an interface.

Figure 4 shows an alternate embodiment of a gas sampling interface.

Figure 5 shows an alternate embodiment of a gas sampling interface.

Figure 6 shows an alternate embodiment of a gas sampling interface.

Figure 7 shows an alternate embodiment of a gas sampling interface.

Figure 8 shows an alternate embodiment of a gas sampling interface.

Figure 9 shows an alternate embodiment of a gas sampling interface.

Figure 10 shows a spline curve representing a series of conduits applied to an alternative embodiment of a gas sampling interface.

Figure 11 shows a spline curve representing a series of conduits applied to an alternate embodiment of the gas sampling interface.

Figure 12 shows a vertical cross-section of an alternate embodiment of a gas sampling interface.

Figure 13 shows a horizontal cross-section of an alternate embodiment of a gas sampling interface.

Figure 14 shows an alternate embodiment of a gas sampling interface.

Figure 15 shows an alternate embodiment of a gas sampling interface.

Figure 16 shows an alternate embodiment of a gas sampling interface.

Figure 17 shows an alternate embodiment of a gas sampling interface.

Figure 18 shows an alternate embodiment of a gas sampling interface.

Figure 19 shows an alternate embodiment of a gas sampling interface.

Figure 20 shows an alternate embodiment of a gas sampling interface.

Figure 21 shows an alternate embodiment of a gas sampling interface.

Figure 22 shows an alternate embodiment of a gas sampling interface.

Figure 23 shows an alternate embodiment of a gas sampling interface.

Figure 24 shows an alternate embodiment of a gas sampling interface.

Figure 25 shows an alternate embodiment of a gas sampling interface.

Figure 26 shows an alternate embodiment of a gas sampling interface.

Figure 27 shows an embodiment of the attachment member of the gas sampling interface.

Figure 28 shows the attachment member of Figure 27 with details of the relative position of the conduit and gas sampling conduit.

Figure 29 shows an alternative embodiment of the attachment member of the gas sampling interface.

Figure 30 shows the attachment member of Figure 29 with details of the relative position of the conduit and gas sampling conduit.

Figure 31 shows an alternative embodiment of the attachment member of the gas sampling interface.

Figure 32 shows the attachment member of Figure 31 with details of the relative position of the conduit and gas sampling conduit.

Figure 33 shows an alternate embodiment of the attachment member of the gas sampling interface.

Figure 34 shows the attachment member of Figure 33 with details of the relative position of the cannula and gas sampling conduit.

Figure 35 shows the connector for the gas sampling interface.

Figure 36 shows the connector of the gas sampling interface.

FIG. 37 shows an alternate embodiment of a gas sampling interface including the connector of FIG. 35 and the connector of FIG. 36 .

Figure 38 shows a side view of an alternative embodiment of a hook of a gas sampling interface.

FIG. 39 shows a perspective view of the hook of FIG. 38 .

FIG. 40 shows a side view of the gas sampling interface and gas sampling conduit of FIG. 38 .

41 shows a perspective view of one side of an alternate embodiment of a gas sampling interface.

FIG. 42 shows a perspective view of another side of the gas sampling interface of FIG. 41 .

Figure 43 shows a perspective view of an alternative embodiment of a hook of a gas sampling interface.

FIG. 44 shows an alternate embodiment of a gas sampling interface incorporating the rigid hook of FIG. 43 .

Figure 45 shows a side view of an alternate embodiment of a gas sampling interface.

FIG. 46 shows a perspective view of the gas sampling interface of FIG. 45 .

Figure 47 shows an alternative embodiment of the hook of the gas sampling interface configured before use.

Figure 48 shows the hook and gas sampling conduit of Figure 47 in its configuration in use.

Figure 49 shows an embodiment of a clip for a gas sampling interface.

Figure 50 shows an alternative embodiment of a clip for the gas sampling interface.

Figure 51 shows an alternative embodiment of a clip for the gas sampling interface.

52 shows a gas sampling catheter attached to a hook by a clip, according to an embodiment.

Figure 53 shows an alternative embodiment of a clip for the gas sampling interface.

Figure 54 shows an end view of an alternative embodiment of a clip for a gas sampling interface.

Figure 55 shows a schematic diagram of another embodiment of a gas sampling interface attached to a nasal cannula.

Figure 56 shows a perspective view of one form of attachment member for attaching a gas sampling catheter to a breathing apparatus.

FIG. 57 shows an end view of the attachment member shown in FIG. 56 .

Figure 58 shows a perspective view of one embodiment of a gas sampling head.

FIG. 59 shows an end view of the distal end of the gas sampling head of FIG. 58. FIG.

FIG. 60 shows an end view of the connection end of the gas sampling head of FIG. 58. FIG.

Figure 61 shows a perspective view of another embodiment of a gas sampling head.

FIG. 62 shows a side view of the gas sampling head of FIG. 61 .

FIG. 63 shows an end view of the distal end of the gas sampling head of FIG. 61 .

FIG. 64 shows an end view of the connection end of the gas sampling head of FIG. 61 .

65 shows a perspective view of a form of gas sampling assembly that includes a gas sampling head connected to a gas sampling tube connected to a luer-style connector.

FIG. 66 shows a side view of the assembly of FIG. 65 .

Figure 67 shows a perspective view of one form, in this case the Luer form, of a connector that can be used to connect a gas sampling catheter to a respiratory gas monitor.

68A and 68B are side views of another form of gas sampling head.

Figure 68C is a cross-sectional side view of the gas sampling head of Figures 68A and 68B.

69A and 69B are side views of another form of gas sampling head.

Figure 69C is a cross-sectional side view of the gas sampling head of Figures 69A and 69B.

70 is a schematic illustration of a patient wearing one form of gas delivery system and one form of gas sampling interface, wherein the head of the gas sampling interface is positioned near the patient's mouth to conduct exhaled and/or exhaled gas from the mouth. sampling.

71 is a schematic illustration of a patient wearing another form of gas delivery system and also wearing the gas sampling interface of FIG. 70, wherein the head of the gas sampling interface is positioned near the nostrils of the patient's nose to control exhalation and/or from the nose. or exhaled breath for sampling.

Domestic storage information (please note in the order of storage institution, date and number) none Foreign deposit information (please note in the order of deposit country, institution, date and number) none

1000: Breathing Equipment

6140: Attachment member

6141: Subject

6163: Gas Sampling Conduit

6167: Fixture

7050: Sampling head

8040: Nasal Cannula

8060: Air Delivery Tube

8070: Manifold

8080: Side Arm

8090: Headband

Claims (20)

A gas sampling interface for use with a high flow breathing gas delivery system, the gas sampling interface comprising: a catheter, the catheter comprising: a first end in fluid communication with a respiratory gas monitor; and a second distal end including at least one inlet for receiving exhaled or exhaled breathing gas from the patient; a gas sampling head located at the distal end of the catheter and comprising a substantially hollow body including at least one gas receiving aperture to receive exhaled or exhaled gas of a patient , wherein the gas receiving hole is in fluid communication with the at least one inlet of the conduit, and wherein the body of the head further includes a distal portion having a distal surface and an outer surface. The gas sampling interface of claim 1, wherein the at least one gas receiving hole is formed in both the distal surface and the outer circumferential side surface such that the gas receiving hole extends from the distal surface and along the The outer surface extends to form an elongated opening in the distal portion of the gas sampling head. The gas sampling interface of claim 1 or 2, wherein the distal portion of the gas sampling head is substantially spherical. The gas sampling interface of any one of claims 1 to 3, wherein the gas sampling head includes three gas receiving holes evenly spaced around the distal end of the sampling head. The gas sampling interface of claim 4, wherein each portion of the body between the gas receiving holes forms a groove, wherein the grooves are substantially around the circumference of the distal portion of the gas sampling head evenly spaced. The gas sampling interface of any one of claims 1 to 5, wherein the gas sampling conduit is connected to a gas sampling tube of the breathing gas monitor via a luer connector. The gas sampling interface of any one of claims 1 to 6, wherein the gas sampling interface is configured to receive a patient receiving breathing gas from a breathing apparatus at a flow rate between about 15 and about 150 L/min The patient exhales or exhales air. The gas sampling interface of any one of claims 1-6, wherein the gas sampling interface is configured to receive a newborn infant patient receiving breathing gas from a breathing apparatus at a flow rate of about 2 L/min/kg breathing gas. The gas sampling interface of any one of claims 1 to 8, wherein at least a portion of the conduit is flexible to allow the inlet to be selectively positioned at the patient's mouth or nose. A gas sampling head removably connected to a distal end of a gas sampling conduit, wherein the sampling head includes a body including a substantially hollow interior region configured in fluid communication with the inlet of the gas sampling conduit when connected to the gas sampling conduit, and wherein the body also includes a distal portion including a distal surface and an outer surface, wherein the gas sampling The head further includes at least one gas-receiving hole connected to the hollow interior region to receive exhaled or exhaled gas of a patient, and wherein the gas-receiving hole is connected to the substantially hollow body of the body. The inner region is in fluid communication. The gas sampling head of claim 10, wherein the at least one gas receiving hole is formed in both the distal surface and the outer circumferential side surface such that the gas receiving hole extends from the distal surface and along the outer side surface extend. The gas sampling head of claim 10 or 11, wherein the at least one gas receiving hole forms an elongated opening in the distal portion of the gas sampling head. The gas sampling head of any one of claims 10 to 12, wherein the distal end of the gas sampling head is outwardly curved. The gas sampling head of claim 13, wherein the distal portion of the gas sampling head is substantially spherical. The gas sampling head of any one of claims 10 to 14, wherein the gas sampling head has a substantially cylindrical shape. The gas sampling head of any one of claims 10 to 15, wherein the gas sampling head includes three gas receiving holes evenly spaced around the distal end of the sampling head. The gas sampling head of claim 16, wherein each portion of the body located between the gas receiving holes forms a groove, wherein the grooves are substantially around the circumference of the distal portion of the gas sampling head evenly spaced. The gas sampling head of any one of claims 10 to 17, wherein the gas sampling head is configured to receive, via a breathing apparatus, a flow of breathing gas from supplied breathing gas at a flow rate between about 15 and about 150 L/min. The exhalation or exhalation of a patient. The gas sampling head of any one of claims 10 to 17, wherein the gas sampling head is configured to receive by a breathing apparatus from a newborn infant supplied breathing gas at a flow rate of about 2 L/min/kg The patient's breath or exhaled air. The gas sampling head of any one of claims 10 to 19, wherein the head is connectable to a gas sampling interface, the gas sampling interface including a conduit including a first conduit in fluid communication with a breathing gas monitor one end and a second distal end attached to the head, the second distal end including at least one inlet for receiving exhaled or exhaled breathing gas from the patient, wherein at least a portion of the conduit is flexible , to allow the inlet to be selectively positioned at the patient's mouth or nose.

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