JP6796617B2 - Systems and methods for removing gas - Google Patents

Description

Embodiments of the present invention generally relate to the field of fluid delivery systems. More specifically, embodiments of the present invention relate to devices and methods for removing air bubbles or other gases from a fluid delivery system.

Air embolism can occur if air bubbles or embolisms are trapped within a blood vessel or heart and interfere with normal blood flow through the blood vessel or heart (eg, venous air embolism (VAE)). The air in the patient's veins travels to the right side of the heart and can reach the lungs from the heart. Air trapped in the blood vessels that supply blood to the lungs can interfere with pulmonary circulation, causing chest pain and respiratory urgency. In some patients, air may move to the left side of the heart and reach the brain or coronary arteries, causing more serious complications. The effects of air embolism are directly related to the size of the embolus and the rate of air entering the blood vessels. 50 ml of air causes hypotension and rhythm abnormalities. When 300 ml of air enters rapidly, it can generally cause death due to circulatory obstruction or cardiovascular collapse.

Air can enter the blood vessels, for example, from a syringe, during surgery or another medical procedure. Air can be taken up in the form of bubbles trapped in a fluid that is introduced into a blood vessel (eg, an intravenous (IV) infusion line that supplies a fluid such as blood for transfusion, saline, or a drug). Small bubbles may be present in the fluid at the time of supply. Further bubbles may also be formed, for example, when the roller clamps are released too rapidly during the preparation of the IV line.

A pump can be used to control the speed of the introduced fluid. Such a pump may include a system for detecting when air is present in the IV line. When air bubbles reach the pump, an alarm sounds to warn the nursing staff or other caregivers and the pump stops. The caregiver should go to the patient and try to remove the air bubbles from the IV line. Every medical institution will have a specific procedure for this process. However, it may include low-tech and / or time-consuming methods such as, for example, "flicking" the IV bag and / or IV line to release air bubbles and collect them at the top of the bag to move away from the outlet.

Hundreds of millions of dollars and significant working hours are spent by a nurse or other caregiver to first prepare the IV line, reset the pump alarm at its start, and purge the air from the IV line. Has been reset. In addition, the alarm built into the pump is a hindrance to the patient as it tends to awaken the patient with each activation.

One embodiment of the present invention relates to an air scavenger for an intravenous infusion system. The air scavenger comprises a housing that includes an inclined cylindrical portion and a main cylindrical portion that define a flow path for the fluid. The housing includes a fluid inlet for fluid communication with the fluid source, a fluid outlet for fluid communication with the patient's blood vessels, and an air outlet. The air scavenger further comprises an air chamber that communicates fluid with the air outlet. The fluid outlet is an opening on one end side of the main cylindrical portion, the air outlet is an opening on the other end side of the main cylindrical portion, and the flow between the fluid outlet and the air outlet. The path extends linearly, the fluid outlet and the air outlet are arranged at opposite ends of the main cylindrical portion of the housing, and the inclined cylindrical portion is relative to the main cylindrical portion. , Inclined toward the air outlet side and connected to the side portion of the main cylindrical portion, the fluid inlet is provided at the distal end of the inclined cylindrical portion, and from the fluid inlet to the fluid outlet. The cross-sectional area of the flow path periodically increases or decreases from the fluid inlet side to the fluid outlet side in at least a part of the flow path between the two.

Another embodiment relates to an intravenous infusion system. The intravenous infusion system includes an inlet through which fluid can enter the intravenous infusion system from an infusion (fluid) bag, an outlet through which the fluid can be dispensed into a patient's blood vessel, and a fluid passing from the inlet to the outlet. It includes a possible passage and an air scavenger located between the inlet and the outlet. The air scavenger includes a housing that includes an inclined cylindrical portion and a main cylindrical portion that define a flow path for the fluid, and an air chamber that communicates the fluid with the housing. The housing includes a fluid inlet for fluid communication with the passage on the inlet side, a fluid outlet for fluid communication with the passage on the outlet side, and an air outlet for fluid communication with the air chamber. .. The air removing device is arranged between the inlet and the outlet so as to prevent air in the passage from flowing beyond the air removing device. The fluid outlet is an opening on one end side of the main cylindrical portion, the air outlet is an opening on the other end side of the main cylindrical portion, and the flow between the fluid outlet and the air outlet. The path extends linearly, the fluid outlet and the air outlet are arranged at opposite ends of the main cylindrical portion of the housing, and the inclined cylindrical portion is relative to the main cylindrical portion. , Inclined toward the air outlet side and connected to the side portion of the main cylindrical portion, the fluid inlet is provided at the distal end of the inclined cylindrical portion, and from the fluid inlet to the fluid outlet. The cross-sectional area of the flow path periodically increases or decreases from the fluid inlet side to the fluid outlet side in at least a part of the flow path between the two.

Another embodiment relates to a method for removing air from a fluid in an intravenous infusion system. The method comprises providing an intravenous infusion system for use with an infusion bag containing the fluid. The intravenous infusion system includes an inlet, an outlet, a passage through which fluid can pass from the inlet to the outlet, and an air scavenger located between the inlet and the outlet. The air removal device includes an air chamber that is configured to passively remove air from a fluid and has a variable internal volume. The method further includes a step of stopping the flow of the fluid through the passage using a clamping device and a step of inserting the inlet into the infusion bag so that the passage communicates with the inside of the infusion bag. And the step of releasing the clamp and allowing the fluid to flow into the passage until the fluid passes through the air scavenger and reaches the outlet. The method further includes a step of stopping the fluid flow through the passage using the clamp device, a step of increasing the internal volume of the air chamber, and a step of releasing the clamp so that the fluid flows through the passage. Includes steps that allow you to do so.

The features, aspects and advantages of embodiments of the present invention will become apparent from the following description, the appended claims and the attached exemplary embodiments shown in the drawings. The drawings will be briefly described below.

FIG. 6 is a schematic representation of a fluid delivery device including an air scavenger according to an exemplary embodiment. It is the schematic of the air removal device by an exemplary embodiment. It is sectional drawing which follows the line 3-3 of the air removal apparatus of FIG. It is sectional drawing which follows the line 4-4 of the air removal apparatus of FIG. It is sectional drawing which follows the line 5-5 of the air removal apparatus of FIG. FIG. 6 is a schematic representation of a divider for an air scavenger according to some other exemplary embodiments. FIG. 6 is a schematic representation of a divider for an air scavenger according to some other exemplary embodiments. FIG. 6 is a schematic representation of a divider for an air scavenger according to some other exemplary embodiments. FIG. 6 is a schematic representation of a divider for an air scavenger according to some other exemplary embodiments. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to various exemplary embodiments. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to various exemplary embodiments. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to another exemplary embodiment. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to another exemplary embodiment. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to another exemplary embodiment. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to another exemplary embodiment. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to another exemplary embodiment. FIG. 6 is a schematic representation of an air chamber for an air scavenger according to another exemplary embodiment. FIG. 6 is a schematic representation of a fluid delivery device, including an air scavenger, according to another exemplary embodiment. FIG. 6 is a schematic representation of a fluid delivery device, including an air scavenger, according to another exemplary embodiment. FIG. 6 is a flow chart of a method for removing air from a fluid in an intravenous infusion system according to an exemplary embodiment.

It will be appreciated that the following detailed description is merely exemplary and descriptive and does not limit embodiments of the invention as described in the claims.

With reference to FIG. 1, a fluid delivery system 10 according to an exemplary embodiment is shown to include an air scavenger 12 (eg, an air catch, a deaerator, etc.). The fluid delivery system 10 is such that the fluid is carried from the fluid source, indicated as the flexible intravenous (IV) bag 16, to the patient through a nearly closed passage, eg, a passage provided by a tube 14 of predetermined length. It is configured in. In other embodiments, the fluid may be sourced from another fluid source, such as a bottle or other closed sterile container. The fluid delivery system 10 can be used to deliver a variety of fluids to a patient's blood vessels. These fluids include bulking agents (eg, saline (NaCl) as fluid replacement to combat dehydration, glucose solutions, etc.), whole blood (eg, blood for transfusion), blood components (eg, red blood cells, plasma, etc.). It includes, but is not limited to, drugs (eg, platelets, etc.) or drugs (eg, chemotherapeutic agents, antibiotics, etc.).

The fluid delivery system 10 may be connected to a catheter that is inserted into a vein through the skin via an appropriate exit connector 15. The veins can be peripheral veins (eg, arm or leg veins) or central veins (eg, head or chest veins). In other embodiments, the fluid delivery system 10 may deliver the fluid into the patient's body through another device, eg, a port embedded in the patient's skin. The outlet connector 15 is configured to be permanently connected (eg, fused using heat or adhesive) to, for example, the outlet of the fluid delivery system 10 and to the corresponding female luer connector. Can be a male luer connector. In other embodiments, the outlet of the fluid delivery system 10 may be connected to the catheter or another device by another type of connector (eg, using a screw type or pressure fitting connector, etc.).

In one embodiment, the flow rate of fluid entering the patient's blood vessels through the fluid delivery system 10 is monitored and controlled by the device shown in FIG. 1 as an infusion pump 18. The infusion pump 18 may deliver the fluid at a constant flow rate or intermittently, either by caregiver or directly by the patient at a frequency determined. A part of the fluid delivery system 10 passes through the infusion pump 18 and directly interfaces with the infusion pump 18 so as to control the fluid flow rate. In one embodiment, the fluid delivery system 10 includes a cassette 20 configured to fit into the corresponding socket of the infusion pump 18. In other embodiments, the fluid delivery system 10 may be free of cassette 20 and the infusion pump 18 may be configured to receive a tube 14 of predetermined length.

In other embodiments, the infusion pump 18 may not be used and the fluid delivery system 10 may be a gravity drip system in which the IV bag 16 is suspended above the patient and the fluid is delivered by gravity. In other embodiments, two or more fluid delivery systems 10 may deliver fluid to the patient through a single catheter or other entry point. In such an embodiment, one or more of the fluid delivery systems 10 may use an infusion pump to control the flow rate, and one or more of the other fluid delivery systems 10 may be a gravity feed system.

The air scavenger 12 removes the air bubbles from the fluid delivery system 10 before they reach the patient. By reducing the amount of air that enters the patient's blood vessels, the likelihood of air-related complications within the blood vessels (eg, air embolism causes embolism) is reduced.

Some infusion pumps 18 may include a system for detecting the presence of a predetermined amount of air in a portion of the fluid delivery system 10 that passes through the infusion pump 18. Such an in-line air detection system may be configured to take precautionary measures (eg, stop the fluid flow in the fluid delivery system 10 and / or alert the caregiver). The alert can be, for example, a voice tone that is activated when air is detected and continues to ring until the air is removed from the fluid delivery system 10 and the infusion pump 18 is reset. If the air scavenger 12 is located upstream of the infusion pump 18 in the fluid delivery system 10, the occurrence of these alerts is reduced, which reduces both patient and caregiver disability.

Further referring to FIG. 1, the fluid enters the fluid delivery system 10 through an inlet indicated as an opening 24 of a spike 25 configured to penetrate the IV bag 16. The spike 25 is connected to a drip chamber 26 suspended under the IV bag 16. The fluid drops or otherwise flows out of the IV bag 16 through the opening 24 at a controlled flow rate and into the drip chamber 26. The dimensions of the opening 24 can be selected to obtain the desired drop diameter and drop rate. When the fluid delivery system 10 is prepared (ie, almost filled with fluid) and in use, the drip chamber 26 is generally only partially filled with fluid. The fluid flows from the drip chamber 26 to the rest of the fluid delivery system 10, while much of the air remains in the drip chamber 26 or returns into the IV bag 16 through the opening 24. However, some air, along with the fluid from the drip chamber 26, can flow to other parts of the fluid delivery system 10.

The fluid flows from the drip chamber 26 through the pipe 14 and through other components (eg, the check valve 28 and the branch pipe or the connector shown as the y-site 22). One fluid delivery system 10 (eg, second set, piggy back set, etc.) may be connected or "piggy back" to another fluid delivery system 10 (eg, first set) via the y-site 22. Good. The y-site 22 is a junction that includes a port 23 (eg, a Mediport, an injection port, etc.) that allows another substance to be introduced into the fluid delivery system 10. The material can be, for example, a second fluid from a second fluid source. The second fluid comes from a fluid source similar to the IV bag 16, from a syringe with a needle pierced into port 23 via a tube interfaced with y-site 22, or by another method (eg, a lure connector or). It can be delivered from a syringe that interfaces with the y-site 22 by another connector (such as a needleless connector). Each of the two fluid delivery systems 10 can operate continuously, one fluid delivery system 10 can operate continuously, while the other fluid delivery system 10 periodically runs the second fluid. Can be added to the first fluid. Alternatively, one (first) fluid delivery system 10 may be stopped while the other (second) fluid delivery system 10 is in operation. The introduction of a second fluid into the fluid delivery system 10 may bring additional air into the system.

Here, with reference to FIG. 2, an air removal device 12 according to an exemplary embodiment is shown. The air scavenger 12 is arranged along the flow path between the inlet and outlet of the fluid delivery system 10 (eg, joined to a pipe 14 that allows fluid to flow from the opening 24 to the outlet connector 15). The air removing device 12 includes a housing 30, which defines an inlet 32, a fluid outlet 34, an air outlet 36, and a flow path 38 for passing fluid from the inlet 32 to the fluid outlet 34 in the housing 30. There is. According to an exemplary embodiment, the housing 30 is formed from a rigid FDA approved material. In one embodiment, the housing 30 is formed as a whole as a main cylindrical portion 31 and an inclined cylindrical portion 33 intersecting the main cylindrical portion 31. The fluid outlet 34 and the air outlet 36 are provided at opposite ends of the main cylindrical portion 31, and the inlet 32 is provided at the distal end of the inclined cylindrical portion 33. The arrangement of the fluid outlet 34 and the air outlet 36 at opposite ends of the housing facilitates the removal of air from the flow path 38.

The main cylindrical portion 31 and the inclined cylindrical portion 33 have an inner diameter configured to accommodate a tube 14, eg, a tube of a standard 1/4 inch (0.635 cm) diameter polymer (eg polypropylene, nylon, etc.). Has. In other embodiments, the main cylindrical portion 31 and the inclined cylindrical portion 33 may be sized to accommodate tubes of different diameters. The pipe 14 is connected to the inlet 32 and the fluid outlet 34 by an appropriate watertight connection mechanism to provide a sterile closed passage from the pipe 14 connected to the inlet 32 through the interior of the housing 30 along the flow path 38. As it passes, it forms up to the pipe 14 connected to the fluid outlet 34. The tube 14 may be permanently connected to the housing (eg, by adhesive, heat staking, etc.) or detachable from the housing, eg, a luer connector, or another suitable screw type or pressure fit. May be connected by.

In other embodiments, the housing 30 may be formed in other shapes. For example, the inside of the housing 30 may be made substantially flat or may have a rectangular cross section. In other embodiments, the inlet 32 and the fluid outlet 34 and the air outlet 36 may be arranged differently with respect to each other. For example, the housing 30 may be T-shaped.

A disrupting device, shown as insert 40 in FIG. 2, is located in the flow path 38 inside the housing 30. At least some of the bubbles in the fluid flowing along the flow path 38 are redirected so that they do not pass through the fluid outlet 34. Instead, the air passes through the air outlet 36 and enters the air chamber 50 outside the flow path 38.

According to one example, the insert 40 is an elongated member made of FDA approved material that does not react in the presence of fluid. The insert 40 can be joined to the inside of the housing 30 using, for example, an adhesive. In another embodiment, the insert 40 is not joined inside the housing 30 but may be held inside the housing 30 by the internal geometry of the housing 30. In another embodiment, the insert 40 can be formed as a single object integrally with the housing 30.

The insert 40 includes a plurality of protrusions 42 (eg, ledges, flanges, baffles, ledges, etc.) extending from the body 44. The protrusions 42 are separated by a notch or a gap 43. The protrusion 42 includes a surface 46 orthogonal to the direction of the fluid flow. The surface 46 impedes the fluid flow in the housing 30 so as to suppress the movement of air bubbles along the flow path 38. In other embodiments, the surface 46 may not be orthogonal to the flow and may instead be tilted at a predetermined angle (eg, upstream, downstream, etc.). Although the surface 46 is shown as a substantially flat surface, in other embodiments, the surface 46 may have other shapes and contours (eg, concave, convex, corrugated, etc.). According to one exemplary embodiment, the insert 40 includes eight protrusions 42 of similar dimensions and shapes arranged at approximately uniform spacing along the length of the insert 40. In another embodiment, the protrusions 42 may be unevenly distributed along the length of the insert 40. In another embodiment, the protrusions 42 may be shaped differently from each other to facilitate the removal of additional air from the fluid.

With reference to FIGS. 3-5, the cross-sectional area of the flow path 38 changes as it passes around the insert 40. The fluid enters the housing 30 at the inlet 32, which has a first cross-sectional area 41 defined by the inner diameter of the housing 30. At the protrusion 42, the surface 46 impedes fluid flow and diverges the fluid around the insert 40 into an annular space defining a second cross-sectional area 45 between the protrusion 42 and the housing 30. Send in. According to an exemplary embodiment, the second cross-sectional area 45 is less than about 50% of the first cross-sectional area 41. According to a preferred embodiment, the second cross-sectional area 45 is less than about 33% of the first cross-sectional area 41. The fluid continues to flow over the protrusions into the intermediate cavity formed by the gap 43. The intermediate cavity has a third cross-sectional area 47 that includes an annular space between the protrusion 42 and the housing 30 and a region between the body 44 and the housing 30. The third cross-sectional area 47 is larger than the second cross-sectional area 45, but smaller than the first cross-sectional area 41.

The protrusion 42 and the flow cross-sectional area that changes along the flow path 38 interrupt the movement of air along the flow path 38. Large bubbles and large amounts of air entering the air scavenger 12 (eg, having a diameter approximately equal to the inner diameter of the tube 14) are disintegrated into small bubbles, detached from the flow path 38, through the air outlet 36 and through the housing 30. Go out from. Relatively small bubbles can be trapped in the intermediate cavity formed by the gap 43 until the diameter of these bubbles is larger, and then escape from the flow path 38 and through the air outlet 36 to the housing. You can get out of 30.

It is believed that the force due to surface tension overcomes the internal pressure of the bubbles as they pass through the limited flow cross-sectional area around the protrusion 42. This reduced flow cross-sectional area crushes the bottom of the bubble, moving the bubble upstream and preventing it from crossing the protrusion. When sufficient air is confined in place, both relatively large bubbles and bubbles formed from small bubbles in one of the gaps 43 are pushed up by the pressure inside the bubbles and away from the protrusion 42.

Here, with reference to FIGS. 6A-6D, some other embodiments of the insert are shown. As shown in FIG. 6A, in one embodiment, the insert 40 may include protrusions 42 extending from a plurality of sides of the body 44. As shown in FIG. 6B, in another embodiment, the insert 40 may include a protrusion 42 extending radially outward from the body 44. As shown in FIG. 6C, in another embodiment, the protrusion 42 can extend inward from the outer housing 30, the flow path 38 can pass through the opening 49 in the protrusion 42, and the insert 40. It does not pass through the annular space between it and the housing 30. As shown in FIG. 6D, in another embodiment, the protrusion 42 may be a wall or plate extending across the interior of the housing, and the flow path may be one or more openings in the protrusion 42. It may pass through section 49 (eg, holes, apertures, slots, etc.).

Here, with reference to FIGS. 7A-7B, an air chamber 50 according to an exemplary embodiment is shown. The air chamber 50 provides a cavity through which air is released from and into the fluid in the flow path 38. Therefore, the air does not continue to flow through the fluid delivery system 10 and does not reach downstream of the air scavenger 12 (eg, to the infusion pump 18 or to the patient). The air chamber 50 penetrates the fluid delivery system through the y-site 22 or other connector from any air that may generally be contained in the IV bag 16 and from other sources (eg, second line or syringe). It is configured to have sufficient internal volume to accommodate the resulting air as well.

In one embodiment, the air chamber 50 is a flexible tubular body with a closed end. The air chamber 50 is formed from an FDA approved material that does not react in the presence of fluid. The air chamber 50 can be formed, for example, from a suitable polymer (eg polypropylene, nylon, etc.). The air chamber 50 is connected to the air outlet 36 of the housing 30 by an appropriate airtight connection mechanism so as to form a sterile closed passage from the inside of the housing 30 to the inside of the air chamber 50. The end of the insert 40 may extend inside the air chamber 50 through the air outlet 36.

The air chamber 50 may be configured to have a variable (eg, expandable) internal volume. As shown in FIG. 7A, in the first or compressed form, the air chamber 50 is bent more than once to reduce the internal volume of the air chamber 50. The air chamber 50 is held in a compressed form using a removable device (shown as a tape 51 of a predetermined length wrapped around a bent air chamber 50). In other embodiments, the air chamber 50 is held in a compressed form using another device, such as a clamp, cable tie, band, strap, hook, and loop strip. The air chamber 50 can be transformed into a second or expanded form to increase the internal volume of the air chamber 50. As shown in FIG. 7B, the elastic properties of the material forming the air chamber 50 automatically expand the air chamber 50 if the tape 51 or other device is removed.

The air chamber 50 may initially be provided in compressed form, for example as part of a fluid delivery system 10 provided in a sealed package. The fluid delivery system 10 may be prepared by being connected to the IV bag 16 by a caregiver and then flowing fluid from the IV bag 16 through the fluid delivery system until it reaches the outlet connector 15. Once the fluid delivery system 10 is prepared, the air chamber 50 can be transformed into an expanded form. Expansion of the air chamber 50 draws fluid (eg, fluid in the housing 30 of the air scavenger 12) from the fluid delivery system 10 and enters the air chamber 50 through the air outlet 36, making the air chamber 50 at least a portion. Fill with fluid. If the fluid delivery system 10 is connected to the patient to deliver the fluid to the patient, the air collected from the fluid can be collected in the air chamber 50 and discharged from the air chamber 50.

The internal volume of the air chamber 50 can be expanded in various ways. For example, in another embodiment shown in FIGS. 8A-8B, the air chamber 50 may have an accordion pleated expandable wall. In the compressed form, the end wall 52 of the air chamber 50 is pushed towards the housing 30. In the extended form, the end wall 52 is separated from the housing 30.

In other embodiments, the cylindrical side wall 54 of the air chamber 50 may be rigid, and the internal volume of the air chamber 50 may be modified with another member. For example, in another embodiment shown in FIGS. 9A-9B, the air chamber 50 has a cylindrical side wall 54 defining a bore and a plunger 56 movable relative to the cylindrical side wall 54. Can include. The head 57 of the plunger 56 engages the inner surface of the cylindrical wall with an airtight interface. As the plunger 56 is pulled away from the housing 30, the internal volume of the air chamber 50 partially defined by the head 57 increases.

In other embodiments, the caregiver may not actively change the capacity of the air chamber 50 after preparing the fluid delivery system 10. For example, in another embodiment shown in FIGS. 10A and 10B, the air chamber 50 may include a flexible bladder 58. In the compressed form, the bladder 58 is not expanded. The bladder 58 is expanded as air is removed from the fluid and enters the air chamber 50. The air chamber 50 may further include a rigid outer housing 59 to protect the bladder from damage or accidental compression. The outer housing 59 includes an opening that allows the expanding bladder 58 to expel air from inside the outer housing 59.

In another embodiment, air may not be collected in the air chamber 50. Instead, the air can exit the air outlet 36, pass through a device such as a low pressure check valve, and be released into the atmosphere. The check valve allows air to be expelled from the fluid delivery system 10 without allowing external contaminants to enter the fluid delivery system 10.

In yet another embodiment, the air can be sent to another enclosure without being collected in the air chamber. For example, the air scavenger 12 is located between the air outlet 36 and another chamber, such as the drip chamber 26 or the IV bag 16, (eg, above the IV bag 16 and above the height of the fluid contained in the IV bag 16. May include a connected return line (through the port above).

Even if the air does not enter the air chamber 50, the air can be effectively removed from the fluid by the air eliminator 12. For example, air bubbles trapped by the insert 40 in the intermediate chamber formed by the gap 43 are prevented from being released from the outlet connector 15 together with the fluid and continuing to enter the patient's blood vessels. Similarly, the air brings the fluid from the inside of the air chamber 50 as described above, but also from the top of the housing 30 (eg, the portion of the main cylindrical portion 31 near the air outlet 36) to the outside of the flow path 38. In addition, the fluid flow passing through the fluid delivery system 10 can be discharged without interruption.

With reference to FIG. 11, a fluid delivery system 60 according to another exemplary embodiment is shown. The fluid delivery system 60 has a configuration similar to that of the fluid delivery system 10 described above. The fluid delivery system 60 includes an additional second air scavenger 62 arranged in series with the air scavenger 12 (first air scavenger 12). Both the first air removing device 12 and the second air removing device 62 are installed upstream of the cassette 20. The second air removing device 62 is arranged downstream of the first air removing device 12 so that the inlet of the second air removing device 62 is connected to the fluid outlet 34 of the first air removing device 12. Therefore, the second air scavenger 62 captures any air that can pass through the first air scavenger 12 and separates the air from the fluid flowing into the cassette 20, whereby the air reaches the cassette 20 and pumps. The 18 reduces the possibility of triggering an alarm.

Here, with reference to FIG. 12, a fluid delivery system 70 according to another exemplary embodiment is shown. The fluid delivery system 70 has a configuration similar to that of the fluid delivery system 10 described above. The fluid delivery system 70 includes an additional second air scavenger 72 arranged in series with the air scavenger 12 (first air scavenger 12). The second air removing device 72 is installed downstream of the cassette 20. Some very small bubbles can pass through the first air scavenger 12. In some cases, such small bubbles can pass through the pump 18 without activating the alarm. The size of such small bubbles may be negligibly reduced enough to affect adults, but it will still be harmful to infants (eg, infants in the neonatal intensive care unit). According to an exemplary embodiment, the second air scavenger 72 may be configured to catch small bubbles that can pass through the first air scavenger 12. Therefore, the second air scavenger 72 is arranged and configured to capture any air that can pass through the first air scavenger 12 and disengage it from the fluid flow to the outlet connector 15, whereby the air reaches the patient. Reduce the possibility.

With reference to FIG. 13, a flowchart of Method 80 according to an exemplary embodiment for removing air from a fluid in an intravenous infusion system is shown. An intravenous infusion system is provided for use with an infusion bag containing the fluid (step 82). The intravenous infusion system includes an inlet, an outlet, a passage through which fluid can pass from the inlet to the outlet, and an air scavenger located between the inlet and the outlet. The air scavenger is configured to passively remove air from the fluid and includes an air chamber with a variable internal volume. The flow of fluid through the passage is stopped using a clamping device (step 84). The flow can be stopped or regulated, for example, using a clamp connected to the tube 14. The clamp may be a roller clamp, a slide clamp, a pinch clamp, or any other mechanism and is configured to partially or completely close the internal passage through the tube 14. This is done by pinching, bending, or otherwise distorting the tube 14. The inlet is inserted into the infusion bag and the passage is inserted so that the fluid communicates with the inside of the infusion bag (step 86). The clamp is disengaged to allow fluid to flow into the passage. The fluid flows through the passage through the air scavenger until it reaches the outlet (step 88). Clamps are usually released fairly slowly to minimize the amount of air bubbles entering the passage. When the fluid reaches the outlet, the fluid flow through the passage is stopped by the clamping device (step 90). The internal volume of the air chamber is increased to draw fluid into the air chamber (step 92). The clamp is then released to allow the fluid to flow through the passage, which allows the air scavenger to remove air from the fluid (step 94).

The terms "approximately," "approximately," "almost," and similar terms used herein are broadly consistent with those commonly accepted by those skilled in the art in the art in which the subject matter of this disclosure relates. It is intended to have meaning. Those skilled in the art reviewing this disclosure are intended to be able to explain some of the features described and claimed without limiting the scope of these features to the exact numerical ranges indicated. You will understand that. Accordingly, these terms are considered to be within the scope of the invention as any insubstantial or insignificant amendments or modifications to the stated and claimed subject matter are set forth in the appended claims. It should be interpreted as indicating that.

As used herein, the terms "connected", "connected", etc. mean connecting two members directly or indirectly to each other. Such a joint can be immobile (eg, permanent) or movable (eg, removable or detachable). Such joining can be achieved by forming the two members, or the two members and any additional intermediate members, integrally with each other as a single body. Alternatively, it can be achieved by attaching two members, or two members and any additional intermediate member to each other.

The representations herein regarding the location of elements (eg, "top", "bottom", "above", "below", etc.) are used solely to describe the orientation of the various elements in the drawing. There is. It should be noted that the orientation of the various elements may vary depending on other exemplary embodiments, and that such changes are intended to be included in this disclosure.

The configuration and arrangement of the elements of the IV line air evacuator as shown in the exemplary embodiments are merely exemplary. Although only a few embodiments of the present disclosure have been described in detail, those skilled in the art who scrutinize the present disclosure will appreciate many modifications (eg, sizes, dimensions, structures, shapes and ratios of various elements, parameter values, mounting arrangements, etc. It will be readily appreciated that the use of materials, changes in color, orientation, etc.) is possible without essentially departing from the novel teachings and advantages of the subject matter described herein. For example, the elements shown to be integrally formed may be composed of a plurality of parts or elements. In the present disclosure, several similar parts are shown in different drawings with the same reference number. This should not be construed to mean that these parts are the same in all embodiments, and various modifications may be made in different embodiments. It should be noted that the elements and / or assemblies of the present disclosure may be composed of any of a variety of colors, textures and combinations thereof, from any of a wide range of materials that provide sufficient strength or durability.

Claims (11)

An air scavenger for intravenous infusion systems
A housing comprising an inclined cylindrical portion and a main cylindrical portion defining a flow path for a fluid, said housing.
Fluid inlet for fluid communication to the fluid source,
A fluid outlet for fluid communication with the patient's blood vessels, and
The air scavenger includes an air outlet, further
The air outlet is provided with an air chamber for fluid communication.
The fluid outlet is an opening on one end side of the main cylindrical portion, and the air outlet is an opening on the other end side of the main cylindrical portion.
The flow path between the fluid outlet and the air outlet extends linearly.
The fluid outlet and the air outlet are arranged at opposite ends of the main cylindrical portion of the housing.
The inclined cylindrical portion is connected to the side portion of the main cylindrical portion so as to be inclined toward the air outlet side with respect to the main cylindrical portion.
The fluid inlet is provided at the distal end of the inclined cylindrical portion .
In at least a part of the flow path between the fluid inlet and the fluid outlet, the cross-sectional area of the flow path periodically increases or decreases from the fluid inlet side to the fluid outlet side.
Air removal device. The air removing device according to claim 1, wherein the air outlet and the air chamber are arranged upstream of the fluid outlet. The air removing device according to claim 1, wherein the air chamber includes a variable internal volume. The air removing device according to claim 3, wherein the air chamber includes a flexible side wall. The air removing device according to claim 3, wherein the air chamber includes an accordion-shaped side wall that can be crushed. The air removal device according to claim 3, wherein the air chamber includes a flexible bladder. Intravenous infusion system
At the entrance where fluid can enter the intravenous infusion system from the infusion bag,
With an outlet where the fluid can be dispensed into the patient's blood vessels,
A passage through which the fluid can pass from the inlet to the outlet,
The air removing device is provided with an air removing device arranged between the inlet and the outlet.
A housing that includes an inclined cylindrical portion and a main cylindrical portion that define a flow path for the fluid.
The housing includes an air chamber that communicates fluid with the housing.
The housing
A fluid inlet for communicating fluid with the passage on the inlet side,
A fluid outlet for communicating fluid with the passage on the outlet side,
Including an air outlet that communicates fluid with the air chamber
The air scavenger is arranged between the inlet and the outlet to prevent air in the passage from flowing beyond the air scavenger.
The fluid outlet is an opening on one end side of the main cylindrical portion, and the air outlet is an opening on the other end side of the main cylindrical portion.
The flow path between the fluid outlet and the air outlet extends linearly.
The fluid outlet and the air outlet are arranged at opposite ends of the main cylindrical portion of the housing.
The inclined cylindrical portion is connected to the side portion of the main cylindrical portion so as to be inclined toward the air outlet side with respect to the main cylindrical portion.
The fluid inlet is provided at the distal end of the inclined cylindrical portion .
In at least a part of the flow path between the fluid inlet and the fluid outlet, the cross-sectional area of the flow path periodically increases or decreases from the fluid inlet side to the fluid outlet side.
Intravenous infusion system. Further including an insertable portion disposed between the air scavenger and the outlet, the insertable portion is configured to be inserted into the pump so that the pump draws fluid through the passage. The intravenous infusion system according to claim 7. The intravenous infusion system of claim 8, further comprising a second air scavenger located between the inlet and the insertable portion. The intravenous infusion system of claim 8, further comprising a second air scavenger located between the insertable portion and the outlet. The intravenous infusion system of claim 8, wherein the insertable portion comprises a cassette configured to interface with the pump.