GB2611046A

GB2611046A - Laryngeal mask airway

Info

Publication number: GB2611046A
Application number: GB2113557.9A
Authority: GB
Inventors: Willmott Henry
Original assignee: Willmott Orthopaedics Ltd
Current assignee: Willmott Orthopaedics Ltd
Priority date: 2021-09-23
Filing date: 2021-09-23
Publication date: 2023-03-29
Anticipated expiration: 2041-09-23
Also published as: WO2023047109A1; GB202113557D0; GB2611046B

Abstract

A laryngeal mask airway 100 comprising: an airway tube 104 that extends from a first end of the laryngeal mask airway to a second end; a monitoring device 106, 108, 110, 112, located towards the first end; and a connector 118 located towards the second end, wherein the connector 118 comprises a communication interface 120 for transmitting signals from the monitoring device to an external device; a method for manufacturing a laryngeal mask airway; and a kit of parts of the laryngeal airway. A laryngeal mask airway 100 comprising: an airway tube 104 that extends from a first end of the laryngeal mask airway to a second end; a monitoring device 106, 108, 110, 112, located towards the first end; and a user interface (200, Fig.3a) near the second end, arranged to output a measurement from the monitoring device. A monitoring structure for fitting to a laryngeal mask airway comprising a monitoring device arranged to monitor vital signs of a user and a connector 118 arranged to connect the laryngeal mask airway to an external device via a communication interface 120.

Description

Laryngeal mask airway

Field of the disclosure

The present disclosure relates to a laryngeal mask airway as well as a method of manufacturing a laryngeal mask airway, a system comprising a laryngeal mask airway, and a device arranged to connect to the laryngeal mask airway.

Backaround to the disclosure

A laryngeal mask airway ([MA) is a supraglotfic airway device that is used to facilitate ventilation of anaesthetised and unconscious patients. The LMA may be used in the emergency treatment of patients in which consciousness is impaired due to head injury, intoxication or cardiac arrest. It may also be used in the operating theatre during induction and maintenance of anaesthesia during surgery. In both of these settings, the [MA supports and maintains the airway, reduces the likelihood of aspiration of gastric contents into the lungs and allows administration of oxygen and anaesthetic gasses either by spontaneous ventilation or positive-pressure ventilation.

Historically, a patient's airway has been secured with a cuffed endotracheal tube (Eli). This device offers a high level of security against gastric contents aspiration, but its use requires a high level of technical skill and the use of a specific device called a laryngoscope to position the tip of the tube appropriately.

An [MA does not offer the same level of airway security as an ETT, but its use is significantly easier, requiring limited technical ability and no laryngoscope. The [MA is therefore widely used in the pre-hospital emergency environment, where it can be quickly and effectively deployed by paramedics or nurses. It is also very commonly used in the elective surgical setting when patients are usually starved and therefore at low risk of gastric aspiration.

A conventional laryngeal mask airway is described by US 4,509,514. The conventional laryngeal mask airway comprises a flexible tube, a mask portion of flexible rubber sheet material, and an inflatable tubular ring of the same rubber material forming its periphery. The distal end of the plastic tube opens into the interior or lumen of the mask portion, being cut off at an angle to the length of the tube to provide an elongated elliptical opening, and being sealed into the mask in an airtight manner so as to form a semi-rigid spine for the mask.

In use, the device is inserted through the patient's mouth through the oropharynyngeal cavity past the epiglottis until the mask comes to rest with the distal end of the ring in the base of the throat, lying against the upper end of the normally closed oesophagus which the mask cannot easily enter because of its size and shape. The ring is then inflated as shown to seal around the inlet to the larynx. The patient's airway is thus secure and unobstructed and the laryngeal -2 -mask can be connected directly to conventional anaesthetic circuit hosing for either positive-pressure ventilation or spontaneous breathing.

More recent developments to LMAs include the i-gele. The i-gel is made of a soft thermoplastic isomer which mirrors the perilaryngeal anatomy and contours the laryngeal inlet.

This negates the need for an inflatable cuff to form an effective seal. Compared to a conventional laryngeal mask airway, the i-gel can enable easier and quicker insertion into the throat, provide reduced trauma and a superior seal pressure, and provide an integrated channel which allows the passage of a gastric tube to decompress the stomach.

Further improvements to laryngeal mask airways are desired.

Summary of the disclosure

According to at least one aspect of the present disclosure, there is described: a laryngeal mask airway comprising: a laryngeal mask; and a monitoring device that is integral to the laryngeal mask.

Preferably, the monitoring device is located such that, in use, the monitoring device is adjacent, and/or in contact with, the upper airway of a user. The user may be a patient into whose throat the laryngeal mask airway is inserted.

Preferably, the monitoring device is located such that, in use, the monitoring device is adjacent, and/or in contact with, the oropharynx of a user.

Preferably, the laryngeal mask airway comprises an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway.

Preferably, the laryngeal mask is arranged near the first end of the laryngeal mask airway.

Preferably, the laryngeal mask airway comprises a connector located at the second end of the laryngeal mask airway, the connector being arranged to connect the laryngeal mask airway to an external device.

Preferably, the connector comprises: a communication interface for transmitting signals from the monitoring device to the external device; and/or a lumen for providing a fluid to an airway tube of the laryngeal mask airway. Preferably, the lumen is suitable for providing a fluid from the external device to the airway tube.

According to another aspect of the present disclosure, there is described: a laryngeal mask airway comprising: an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; a plurality of monitoring devices located near (and/or at and/or towards) the first end of the laryngeal mask airway; and a connector located near (and/or at and/or towards) the second end of the laryngeal mask airway; wherein the -3 -connector comprises a communication interface for transmitting signals from the plurality of monitoring devices to an external device.

Preferably, the monitoring device being towards the first end comprises the monitoring device being closer to the first end of the laryngeal mask airway than the second end of the laryngeal mask airway.

Preferably, the communication interface of the connector is arranged to transmit signals from each of the monitoring devices to the external device. Preferably, the communication interface is arranged to transmit signals from each of the plurality of monitoring devices to the external device via a single connection. Preferably, the communication interface comprises a single plug and/or a single socket.

According to another aspect of the present disclosure, there is described: a laryngeal mask airway comprising: an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; a monitoring device located near (and/or at and/or towards) the first end of the laryngeal mask airway; and a connector located near (and/or at and/or towards) the second end of the laryngeal mask airway; wherein the connector comprises: a communication interface for transmitting signals from the monitoring device to an external device; and a lumen for providing a gas to the airway tube of the laryngeal mask airway.

Preferably, the laryngeal mask airway comprises a laryngeal mask. Preferably, the laryngeal mask is located at the first end of the laryngeal mask airway. Preferably, the airway tube extends from the laryngeal mask.

Preferably, the connector is arranged to connect the laryngeal mask airway to an/the external device.

Preferably, the monitoring device is mounted on the laryngeal mask airway. Preferably, the monitoring device is integral to the laryngeal mask airway. Preferably, the laryngeal mask airway comprises a laryngeal mask and the monitoring device is integral to a laryngeal mask of the laryngeal mask airway.

Preferably, the monitoring device is located such that, in use, the monitoring device is adjacent to, and/or in contact with, the oropharynx and/or the upper airway of a user.

Preferably, the communication interface of the connector is located adjacent the lumen of the connector. Preferably, the connector is collinear to the airway tube, and/or adjacent to the airway tube, and/or integral with the airway tube.

Preferably, the laryngeal mask airway comprises a plurality of monitoring devices. -4 -

Preferably, two or more of the plurality of monitoring devices share componentry. Preferably, two or more of the plurality of monitoring devices share a shared light emitting diode. Preferably, the laryngeal mask airway comprises a light emitting diode that is used by a pulse oximeter and also a blood pressure monitor.

Preferably, the laryngeal mask airway comprises one or more of: a temperature sensor; a blood pressure monitor, preferably a photoplethsmography (PPG) blood pressure sensor; a pulse oximeter; two or more electrocardiogram electrodes; and a CO2 detector or tube to enable gas sampling for connection to an external CO2 detector.

Preferably, the laryngeal mask airway comprises a plurality of electrocardiogram electrodes.

Preferably, the laryngeal mask airway comprises a first electrocardiogram electrode at a first end of the laryngeal mask airway and a second electrocardiogram electrode at a second end of the laryngeal mask airway. Preferably the second electrocardiogram is located so that, in use, the second electrocardiogram electrode is in contact with the lips of a user.

Preferably, the laryngeal mask airway comprises wiring to conned the monitoring device to a communication interface of the laryngeal mask airway. Preferably, the laryngeal mask airway comprises wiring to connect one or more monitoring devices located at a first end of the laryngeal mask airway to a communication interface located at a second end of the laryngeal mask airway.

Preferably, the wiring is attached to, secured to, and/or mounted on, the airway tube.

Preferably, the wiring is located adjacent the airway tube. Preferably, the wiring is located inside the airway tube. Preferably, the wiring is aligned with the airway tube.

Preferably, the laryngeal mask airway comprises a connector for connecting the laryngeal mask airway to an external device. Preferably, the laryngeal mask airway comprises a connector for connecting a/the communication interface of the laryngeal mask airway to an external device.

Preferably, the connector comprises a lumen for providing a fluid to an airway tube of the laryngeal mask airway.

Preferably, the connector and/or a/the communication interface is arranged to enable the external device to: output a measurement of the monitoring device; and/or provide power to the monitoring device; and/or control the monitoring device.

Preferably, the connector comprises a push fit connector. Preferably, the connector comprises a flange Preferably, the monitoring device is arranged so that, in use, the monitoring device is in direct -5 -contact with the throat and/or oropharynx of a user.

Preferably, the laryngeal mask airway comprises a power source Preferably, the power source is arranged to provide power to the monitoring device.

Preferably, the laryngeal mask airway comprises a user interface. Preferably, the user interface is arranged to output a measurement from the monitoring device.

Preferably, the laryngeal mask airway comprises an integral user interface and/or an integral power source According to another aspect of the present disclosure, there is described a laryngeal mask airway comprising: an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; a monitoring device located near the first end of the laryngeal mask airway; and a user interface near the second end of the laryngeal mask airway, wherein the user interface is arranged to output a measurement from the monitoring device.

Preferably, the user interface is arranged to output an oxygen saturation. Preferably, the user interface is arranged to output an oxygen saturation measured by a/the pulse oximeter.

Preferably, the user interface is arranged to output measurements from a plurality of devices. Preferably, the user interface is an integral part of the laryngeal mask airway Preferably, the laryngeal mask airway is arranged such that the operation of the laryngeal mask airway is dependent on whether the laryngeal mask airway is connected to an external device.

Preferably, the monitoring device is arranged to draw power from a battery of the laryngeal mask airway when the laryngeal mask airway is not connected to an external device.

Preferably, the monitoring device is arranged to draw power from an external device when the laryngeal mask airway is connected to an external device.

Preferably, the laryngeal mask airway comprises a processor for detecting a type and/or identity of an external device to which the laryngeal mask airway is connected.

Preferably, the laryngeal mask airway comprises a processor for processing signals received from the monitoring device before transmission to an external device.

Preferably, the laryngeal mask airway comprises a communication interface. Preferably, the laryngeal mask airway comprises a wireless communication interface.

Preferably, the laryngeal mask airway comprises an anaesthetic mechanism for providing a fluid, preferably a gas, to an airway tube of the laryngeal mask airway. -6 -

Preferably, the anaesthetic mechanism is arranged to operate in dependence on the monitoring device.

According to another aspect of the present disclosure, there is described a device arranged to interface with the laryngeal mask airway of any preceding claim. Preferably, the device is arranged to provide a fluid to an/the airway tube of the laryngeal mask airway. Preferably, the device is arranged to provide a fluid to an/the airway tube of the laryngeal mask airway in dependence on the monitoring device of the laryngeal mask airway.

Preferably, the device comprises a user interface.

According to another aspect of the present disclosure, the device comprises a portable device. For example, the device may comprise a portable user interface that can be connected at the scene of an accident so that first responders can monitor the blood oxygen saturation of a user.

According to another aspect of the present disclosure, there is described a monitoring structure for fitting to a laryngeal mask airway, the monitoring structure comprising a monitoring device arranged to monitor a vital sign of a user.

According to another aspect of the present disclosure, there is described a method of manufacturing the laryngeal mask airway of any preceding claim.

According to another aspect of the present disclosure, there is described a method of manufacturing a laryngeal mask airway, the method comprising: forming an airway tube; forming a laryngeal mask at a distal end of the airway tube; locating a monitoring device adjacent the laryngeal mask; locating a connector at a proximal end of the airway tube.

Preferably, the method comprises connecting a wire between the monitoring device and the connector.

According to another aspect of the present disclosure, there is described a method of manufacturing a laryngeal mask airway, the method comprising: forming an airway tube; forming a laryngeal mask; forming a monitoring structure comprising: a monitoring device; a connector; and, preferably, a wire between the monitoring device and the connector; and fitting the monitoring structure to the airway tube and/or the laryngeal mask According to another aspect of the present disclosure, there is described a kit of parts comprising: a laryngeal mask airway comprising an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; a monitoring device arranged to be mounted towards the first end of the laryngeal mask airway; and a connector arranged to be attached to the second end of the laryngeal mask airway, wherein the connector comprises a communication interface for transmitting signals from the -7 -monitoring device to an external device.

Preferably, the monitoring device is arranged to be mounted on a laryngeal mask located at the first end of the laryngeal mask.

According to another aspect of the present disclosure, there is described a method of using the aforesaid laryngeal mask airway.

According to another aspect of the present disclosure, there is described a method of: inserting the aforesaid laryngeal mask airway into the throat of a user; and monitoring one or more vital signs of the user with the monitoring device of the laryngeal mask airway. Preferably, the method comprises monitoring the vital sign using a/the user interface of the laryngeal mask airway.

Any feature in one aspect of the disclosure may be applied to other aspects of the invention, in any appropriate combination. In particular, method aspects may be applied to apparatus aspects, and vice versa.

Furthermore, features implemented in hardware may be implemented in software, and vice versa. Any reference to software and hardware features herein should be construed accordingly.

Any apparatus feature as described herein may also be provided as a method feature, and vice versa. As used herein, means plus function features may be expressed alternatively in terms of their corresponding structure, such as a suitably programmed processor and associated memory.

It should also be appreciated that particular combinations of the various features described and defined in any aspects of the disclosure can be implemented and/or supplied and/or used independently.

The disclosure extends to methods and/or apparatus substantially as herein described with reference to the accompanying drawings.

The disclosure will now be described, by way of example, with reference to the accompanying drawings.

Description of the Drawings

Figure 1 shows a laryngeal mask airway according to the present disclosure.

Figure 2 shows an embodiment of a connector of the laryngeal mask airway.

Figures 3a, 3b, and 3c show laryngeal mask airways that comprise a user interface. Figure 4 illustrates the laryngeal mask airway in use. -8 -

Description of the preferred embodiments

A conventional laryngeal mask airway (LMA) has been described in the background above. This LMA allows the effective maintenance and protection of a patient's airway.

When treating an unconscious or anaesthetised patient, it is desirable to monitor the patient's vital signs. This ensures that the airway, ventilation and oxygenation are adequate. Therefore, while the laryngeal mask airway is being used, a healthcare professional may also perform one or more of: Pulse oximetery: pulse oximetry is a method for measuring the oxygen saturation of the blood (e.g. what proportion of the haemoglobin in blood is carrying oxygen). Pulse oximetry is traditionally performed using a finger-tip device, which fits like a clothes peg on the tip of a finger. Two diodes emit red and near-infrared light and the relative amount of light absorbed is used to calculate oxygen saturation. The light may be passed through a digit, known as transmittance pulse oximetry, or reflected off the skin, known as reflectance pulse oximetry.

Blood pressure monitoring: blood pressure is a product of cardiac output and vascular resistance and is an important measure of organ perfusion. There are many ways in which blood pressure can be monitored. The most commonly used is the use of an inflatable cuff around the upper arm attached to an automatic device which measures oscillations of pressure during gradual deflation of the cuff. More recently, blood pressure monitoring devices have been developed which use optical methods, known as photoplethysmograpy (PPG).

Heart monitoring (e.g. heart rhythm monitoring): typically heart monitoring comprises monitoring the electrical activity of the heart so as to identify rhythm abnormalities, shock or ischaemia. This can be achieved with an electrocardiogram (ECG). Typically, an ECG involves placing three electrodes on the chest wall to obtain readings of potential difference between them. The heart rate can also be derived from the pulse oximeter trace.

End tidal CO2 monitoring: detection of carbon dioxide in exhaled air indicates proper airway placement and adequate perfusion of core organs. End tidal CO2 is usually monitored with a fine tube attached to the ventilator circuit. Gas is sampled from the circuit and passed over a CO2 detector.

Temperature monitoring: body temperature -and in particular core body temperature -is an important parameter to measure in both the emergency resuscitation and the elective surgery settings. Patients can rapidly become cold when under anaesthetic due to lack of -9 -muscle activity and exposure of body cavities to the environment during surgical procedures. In cardiac arrest or when patients are exposed to the environment, hypothermia may occur. Increased temperature can indicate allergy or abnormal reaction to anaesthetic drugs. Core temperature is usually measured with a probe inserted into the pharynx or larynx.

Performing this monitoring while using a conventional laryngeal mask airway requires multiple leads and connections. An unconscious, sedated or anaesthetised patient may have attached to them: three ECG leads, a pulse oximeter lead, an end tidal CO2 tube and a temperature probe in addition to a ventilator circuit. Connecting all of these cables takes a substantial amount of time, and the presence of these cables makes it difficult to move and transport patients. This can be a particular problem in emergency situations such as the pre-hospital environment.

Referring to Figure 1, there is described a laryngeal mask airway 100 according to the present disclosure that comprises one or more monitoring devices; this enables the monitoring of one or more of the above vital signs without the need for further sensors. It will be appreciated that the laryngeal mask airway may comprise any combination of the monitoring devices mentioned in this description.

The laryngeal mask airway 100 comprises a laryngeal mask 102 that is inserted into the pharynx of a patient. The laryngeal mask is typically formed of a thermoplastic isomer.

The laryngeal mask airway further comprises an airway tube 104 that provides an airway between the trachea of the patient and the exterior of the patient. The combination of the laryngeal mask and the airway tube enables the laryngeal mask airway to be inserted into the pharynx of a patient to maintain the patency of the airway, to enable spontaneous or positive-pressure ventilation of a patient, and/or to enable the administration of anaesthetic gasses via the airway tube.

For the purposes of this description, the laryngeal mask airway 100 is described in terms of a distal end and a proximal end (more generally, the laryngeal mask airway comprises a first end and a second end). The laryngeal mask 102 is located at the distal end of the laryngeal mask airway, which is inserted into the pharynx of a patient. The airway tube 104 extends from this laryngeal mask at the distal end of the laryngeal mask airway to the proximal end of the laryngeal mask airway. The proximal end of the laryngeal mask airway is arranged to protrude from the lips of the patient when the laryngeal mask airway is inserted.

The laryngeal mask airway 100 of the present disclosure comprises one or more monitoring devices. For example: -10 - - A temperature sensor 106. The temperature sensor enables monitoring of the core temperature of the patient and can be used to determine whether this core temperature of a patient is outside of a desirable range (in particular, if the patient is hypothermic). Positioning the sensor centrally within the patient's body increases the accuracy of detection of hypothermia as compared to an external temperature sensor and avoids inaccuracy associated with peripheral vasoconstriction which can affect peripherally positioned monitoring devices.

- A blood pressure monitor 108. In particular, the laryngeal mask airway 100 may comprise a photoplethysmograpy (PPG) blood pressure monitor. Equally, the laryngeal mask airway may comprise a blood pressure monitor that is an inflatable balloon and/or a cuff on the back of the laryngeal mask airway 100.

A pulse oximeter 110. In particular, the laryngeal mask airway 100 may comprise a light emitter or pair of light emitters that are arranged to determine an amount of infrared and near-infrared light that passes through and/or is reflected from the mucus membrane surface of the pharynx. The central location of the pulse oximeter offers increased accuracy of readings by avoiding interference from peripheral vascoconstruction, skin tone, skin contamination or ambient light, all of which are encountered when oximetry is performed peripherally. The trace derived from the pulse oximeter monitor may also be used to monitor heart rate.

-A first and/or second electrocardiogram electrode 112-1, 112-2. In particular, a first electrocardiogram electrode 112-1 may be provided at the distal end of the laryngeal mask airway and a second electrocardiogram electrode 112-2 may be provided nearer the proximal end of the laryngeal mask airway. The second electrocardiogram electrode 112-2 may comprise an earthing electrode and may be arranged to contact the lips of the patient.

An end tidal CO2 inlet 114. Typically, the end tidal CO2 inlet is located near the proximal end of the laryngeal mask airway so that it can determine the amount of CO2 present in exhaled air. Sampling gas from within the airway tube of the laryngeal mask airway itself, rather than from a point more proximally in the airway circuit, reduces dead space and increases accuracy and speed of detection.

These monitoring devices are typically arranged towards the distal end of the laryngeal mask airway 100/airway tube 104 so that the monitoring devices are able to measure vital signs from inside a patient.

These monitoring devices may require an electrical connection to provide power to the monitoring devices and/or to enable the monitoring devices to provide a reading. Therefore, the laryngeal mask airway 100 typically comprises wiring 116 that links one or more monitoring devices located at the distal end of the laryngeal mask airway to a connector at the proximal end of the laryngeal mask airway. The wiring is typically mounted to, secured on, and/or aligned with, the airway tube 104 of the laryngeal mask airway. This enables a compact laryngeal mask airway to be provided and also prevents loose wiring from damaging the throat of a patient.

The laryngeal mask airway may comprise a wiring compartment located adjacent to, and/or or within the wall of, the airway tube 104 so that the wiring is outside of the lumen of the airway tube. This wiring compartment may have an exterior that is shaped (and/or composed of a suitable material) so as to sit comfortably inside the throat of a patient.

The laryngeal mask airway 100 may comprise a power source (e.g. a battery) and/or a user interface (e.g. a display and/or a speaker) so that the laryngeal mask airway can be used as a standalone device. In particular, the laryngeal mask airway may comprise a power source for providing power to a monitoring device and/or a user interface. For example, the laryngeal mask airway may comprise a power supply that provides power to a pulse oximeter and to a display, which display shows the oxygen saturation measured by that pulse oximeter. Such an implementation can be particularly beneficial for first responders in a pre-hospital environment. Where the laryngeal mask airway comprises a power source or a user interface, this power source and/or user interface is typically arranged near the proximal end of the device so that neither component is inserted into the throat of a patient and so that the user interface can be clearly seen by a user. It will be appreciated that a power source could be provided without a user interface (and vice versa).

Where the laryngeal mask airway 100 comprises a user interface, this user interface is typically arranged to output a measurement of one or more of the monitoring devices and/or to provide an output in dependence on one or more vital signs of the patient. For example, the user interface may output an alarm if the patient's oxygen saturation falls below a threshold value or an audible signal (bleep) may be emitted to reflect the patient's heart rate, the tone of which may reflect the patient's oxygen saturation. The user interface may also enable a user to control an aspect of the monitoring devices (e.g. to control a sensitivity of a monitoring device).

Typically, the laryngeal mask airway 100 is arranged to connect to an external device; for example, the laryngeal mask airway may be connected to a computer device or anaesthetic machine with a large user interface that outputs readings from the monitoring devices. The laryngeal mask airway 100 may be arranged so that the monitoring devices are arranged to receive power from the external device, to provide readings to the external device, and/or to -12 -receive control signals from the external device (e.g. to control an intensity of light emitted from a pulse oximeter).

Referring to Figures 1 and 2, in order to conned the monitoring devices to such an external device, the laryngeal mask airway 100 typically comprises a connector 118 located at the proximal end of the airway tube 104 (e.g. adjacent with and/or collinear with the airway tube).

The connector comprises a terminal 120 that receives the wiring 116 from the monitoring devices and forms an interface between this wiring and the wiring of an external device. Typically, the connector is arranged to receive a plug from an external device (this plug may, for example, comprise a USB connector). The connector may comprise a plurality of terminals to enable each of the monitoring devices of the laryngeal mask airway can be connected to a separate external device. However, typically the connector comprises a combined terminal so that a single connection can be used to connect a plurality of (e.g. all of) the monitoring devices to a single external device.

As shown in Figure 2, typically the connector 118 also comprises a lumen 122 for providing a fluid Cr particular gasses, air or oxygen) to the airway tube 104. This enables a single plug to be inserted in order to carry both signals from the monitoring devices to an external device and anaesthetic gasses, oxygen or air from the external device to the airway tube. Typically the connector is an integral part of the laryngeal mask airway, and in this case the lumen 122 of the connector may be a part of the airway tube 104 (e.g. the proximal end of the airway tube).

Equally, the connector may be an attachable/removable component, where the connector 118 may be inserted into the end of the laryngeal mask airway 100 such that the lumen 122 of the connector aligns with the airway tube 104 of the laryngeal mask airway. In such an embodiment, the connector may comprise an attachment structure to ensure that it connects securely to the laryngeal mask airway. This attachment structure may comprise a sloped surface extending from the lumen so that this sloped surface of the connector can be pushed into the airway tube of the laryngeal mask airway to provide a secure interference fit.

The connector 118 (and thus the laryngeal mask airway 100) is arranged to connect to an external device so that the external device is able to interface with the monitoring devices via the terminal 120 and/or so that the external device is able to interface with the airway tube 104 via the lumen 122, In some embodiments, including embodiments where the laryngeal mask airway 100 is arranged to be connected to an external device and embodiments where the laryngeal mask airway is arranged to be used as a standalone device (e.g. with a user interface), the laryngeal mask airway comprises a processor for processing signals from the monitoring devices and/or -13 -a power supply for powering the monitoring devices. The processor may be arranged to determine whether a vital sign of the patient has exceeded and/or fallen below a threshold. This processor may be arranged to output (via a user interface) an audio or visual alarm signal. In some embodiments, the user interface comprises a digital display screen that is arranged to display alphanumeric signals to the user (e.g. a numerical value of oxygen saturation or temperature).

Typically, the connector 118 comprises a push-fit connector, where this enables a user to make a simple and quick connection between the connector and a plug (which plug is connected to an external device). The connector 118 may comprise a flange 124 to ensure a correct connection and to ensure that the plug is not pushed too far into the connector. This also enables a user to grasp the connector beneath the flange to ensure that the laryngeal mask is not pushed into the patient as the plug is pushed into the connector. It will be appreciated that various types of connector are useable (e.g. push fit, interference fit, twist connectors, magnetic connectors, etc.) where the choice of connector may depend on the use of the laryngeal mask airway. A push-fit connector can be beneficial due to the ease of use and the speed of connection.

While Figure 1 shows a terminal that is aligned with the airway tube 104 so as to enable a single plug to interface with both the airway tube 104 and the terminal 120, it will be appreciated that variations of this arrangement are possible. For example, the terminal may be arranged so that a plug can be inserted into the terminal perpendicular to the airway; similarly, the terminal may be located away from the airway tube so that separate connections are required to interface with the terminal and to interface with the lumen 122.

One or more of the monitoring devices is typically integral to the laryngeal mask 102 and/or is arranged to be On use) in direct contact with the throat of a patient. More specifically, one or more of the monitoring devices is typically arranged to be in direct contact with the mucus membranes of the upper airway of the patient when the laryngeal mask airway 100 is inserted.

The monitoring devices may be positioned on the tip of the laryngeal mask 102, the back of the laryngeal mask and/or (more proximally) along the airway tube in order to maximise their efficiency and prevent interference with one another. In some embodiments, two or more of the monitoring devices share componentry; for example, a shared light emitting diode (and/or a shared pair of light emitting diodes) may be used for both pulse oximetry and blood pressure detection) Central placement of the monitoring devices enables accurate measurement of the vital signs of the patient and because the detectors are in intact with central internal tissues, rather than the tissues of peripheries or digits, errors caused by peripheral vasoconstriction, skin -14 -contamination or bright ambient light are avoided. Conventionally, these benefits of internal monitoring devices would be offset by the invasive nature of the devices. That is, it is undesirable to place a conventional laryngeal mask airway into the throat a patient and then to insert separately other monitoring devices into the throat since these separate devices could interfere with the conventional laryngeal mask airway and/or since the combination of the laryngeal ask airway and separate devices could cause undesirable trauma to the patient. With the present disclosure, only the laryngeal mask airway 100 (that comprises integrated monitoring devices) needs to be inserted -and the inclusion of the monitoring devices within the laryngeal mask airway enables the provision of a compact apparatus.

A common use of the laryngeal mask airway 100 is to introduce a fluid (e.g. air, oxygen or gas) to the lungs of a patient via the airway tube 104. In particular, anaesthetic gasses may be provided to the airway tube in order to induce and maintain anaesthesia. Therefore, the connector 118 may be arranged to receive a plug from an anaesthetic machine that is arranged to provide a fluid (and in particular an anaesthetic gas) to the airway tube 104 as well as to receive signals from the monitoring device(s) via the terminal 120. More specifically, the connector may be arranged to receive a plug that comprises a plug tube and a plug terminal, where: the plug terminal comprises wiring that interfaces with the wiring 116 of the laryngeal mask airway via the terminal 120 of the connector; and the plug tube interfaces with the airway tube 104 of the laryngeal mask airway via the lumen 122 of the connector (so that gas can be injected into the airway tube via the plug tube). As shown in Figure 2, the terminal of the connector may be arranged near the perimeter of the connector so as not to block the flow of a fluid through the lumen of the connector.

The laryngeal mask airway 100 may be arranged to interact with an anaesthetic machine so that the operation of the anaesthetic machine is dependent on the monitoring device(s) of the laryngeal mask airway (e.g. so that the operation of the anaesthetic machine is dependent on a signal from the monitoring device(s) of the laryngeal mask airway). For example, if a reduction of blood oxygen saturation is detected by the monitoring device, the anaesthetic machine may automatically increase the delivered partial pressure of oxygen to the airway tube 104.

Typically, the laryngeal mask airway 100 is used with an anaesthetic machine that also comprises a user interface, so that plugging the connector 118 into the fluid injection machine enables a flow of anaesthetic gas to be provided while also enabling the monitoring devices to provide an output via this user interface.

-15 -The laryngeal mask airway 100 may also be used with a manual bag-valve device as used for resuscitation of patients in an emergency setting. The connector 118 may be arranged to be compatible with such bag-valve devices.

The present disclosure extends to an external device that is arranged to interact with the laryngeal mask airway 100, in particular an external device that is arranged to provide a gas to the airway tube 104, where the provision of gas is dependent on the monitoring device(s) of the laryngeal mask airway.

As has been described above, the laryngeal mask airway 100 may comprise its own user interface that enables the laryngeal mask airway to be used without being connected to an external device or when connected to a simple mechanical bag-valve manual ventilator.

Figures 3a, 3b, and 3c show embodiments of such a laryngeal mask airway.

Referring to Figure 3a, there is shown an embodiment of the laryngeal mask airway 100 that comprises a user interface 200 located at the proximal end of the laryngeal mask airway (near the connector 118). This enables a user to view an output of a monitoring device, e.g. to view an oxygen saturation of a patient's blood that is output by the pulse oximeter 110.

As shown in Figure 3b, the user interface 200 may, for example, comprise a display arranged to output a numerical value. It will be appreciated that various user interfaces are possible, e.g. a speaker, or a touchscreen. The user interface may enable a user to view a plurality of outputs at once and/or to cycle through the outputs of the various monitoring devices.

As shown in Figures 3a and 3b, this user interface 200 is typically provided along with the connector 118 so that an external device can still be connected to the laryngeal mask airway 100 Typically, such an implementation of the laryngeal mask airway 100 also comprises a processor that is arranged to control the user interface 200. This processor is typically located near the user interface at the proximal end of the laryngeal mask airway.

Referring to Figure 3c, the user interface 200 may be removable from/connectable to the laryngeal mask airway 100. In particular, there may be provided a user interface that is arranged to be inserted into the connector 118, which user interface comprises an interface connector 204 to enable the insertion of a plug from an external device. This enables the laryngeal mask airway to be provided so that: an external machine can be plugged directly into the connector; or a user interface can be plugged into the connector and then an external device can be plugged into an interface connector of this user interface.

-16 -The arrangement of Figure 3c enables the use of a range of different user interfaces with a single laryngeal mask airway, where these different user interfaces may be intended for different purposes or users.

Figure 4 illustrates the usage of the laryngeal mask airway 100 of the present invention.

Specifically, Figure 4 shows the laryngeal mask airway 100 when it is inserted into the throat of a patient.

After (or before) the laryngeal mask airway 100 has been inserted into the upper airway of a patient a plug may be inserted into the connector 118 in order to connect the monitoring devices of the laryngeal mask airway 100 to an external (output) device.

When a patient needs to be moved between locations: the plug is disconnected; the patient is moved; and then a new plug is inserted (that links to an external device at the new location). The plug may be associated with an anaesthetic machine, such that the connection of the plug to the connector 118 enables the provision of gas to the patient from the anaesthetic machine. Conventionally, the moving of the patient would require numerous monitoring devices to be disconnected at the old location and then numerous other monitoring devices to be connected at the new location. The present disclosure requires only a single plug to be connected. This enables rapid movement of the patient and minimises the time during which the vital signs of the patient are not being monitored.

In order to further speed up the setup of the laryngeal mask airway 100, and the transfer of a patient between locations, the laryngeal mask airway may comprise a processor for detecting whether the laryngeal mask airway is connected to an external device and/or for detecting a type and/or identity of an external device to which the laryngeal mask airway is connected. In particular, the laryngeal mask airway may be able to identify whether it is connected to a basic external device (e.g. in an ambulance) or to a more sophisticated or complex external device (e.g. in an operating theatre) and to alter its operation accordingly. For example, where the laryngeal mask airway is connected to an external device with a single screen it may provide an output signal with limited detail, e.g. an output that shows only the most critical vital sign. Where the laryngeal mask airway is connected to an external device with numerous screens it may provide a more detailed output signal that enables more information to be seen. This functionality enables the laryngeal mask airway to quickly and simply be used in a range of situations.

Furthermore, the laryngeal mask airway 100 may be arranged to determine a use case and/or a user profile based on an external device to which it is connected. In this regard, different operations and/or different users may require the monitoring of different vital signs and the -17 -laryngeal mask airway may determine which vital signs to output based on signals received from an external device when the laryngeal mask airway is connected to this external device.

Typically, the monitoring devices of the laryngeal mask airway 100 output signals that are arranged to be processed at an external device. For example, the electrocardiogram electrodes 110-1, 110-2 typically provide raw data that is processed at the external device to extract RR intervals and to determine a heart rate.

The laryngeal mask airway may be arranged to determine whether a connected external device has the capability to process data provided by the monitoring devices and may provide output signals accordingly (so that if the external device is able to process electrocardiogram data and blood oximetry data but not blood pressure data, then the blood pressure monitor may be switched off).

The connector 118 of the laryngeal mask airway 100 may comprise a plurality of terminals, with each terminal being associated with a different monitoring device. This enables the data from each monitoring device to be readily separated and analysed.

However, typically the connector 118 of the laryngeal mask airway 100 comprises a single terminal 120 so that a single plug can be used to receive data from all of the monitoring devices.

In some embodiments, the laryngeal mask airway 100 comprises a processor and/or storage for receiving and/or storing data from the monitoring devices. The processor may be arranged to process the raw data from the monitoring devices, e.g. to combine the data from multiple monitoring devices into a single output signal that is provided at a single terminal.

In order to transfer signals from the monitoring devices to an external device, the laryngeal mask airway 100 comprises a communication interface. Typically, this communication interface comprises the terminal 120. The communication interface may comprise any form of wired interface, such as a universal serial bus (USB) connection. Equally, the communication interface may comprise a wireless interface, such as a Bluetoothe interface and/or a local area network interface. The use of a wireless interface enables the data from the monitoring devices to be transmitted to an external device without the need of a wired connection, which can further simplify the use of the laryngeal mask airway and the transportation of patients.

The communication interface may be arranged to pair with an external device to facilitate this transmission. VVhere a wireless communication interface is provided, this interface is typically provided near the proximal end of the laryngeal mask airway (so that in use it is outside of the throat of the patient). Therefore, there is typically still the wiring 116 running along the laryngeal mask airway connecting the monitoring devices to the wireless communication interface. In some embodiments, one or more of the monitoring devices comprises an -18 -individual wireless communication interface, so that additional wiring is not necessary for this monitoring device.

The present disclosure also extends to a plug for use with the laryngeal mask airway 100, and in particular for use with the connector 118 of the laryngeal mask airway, as well as an external device that comprises such a plug. The plug may comprise an electrical connection for transmitting signals from the monitoring devices to the external device as well as a tube for enabling the flow of gas between the airway tube 104 and the external device (or the atmosphere).

Manufacturing the laryngeal mask airway 100 may comprise forming the airway tube 104 and the laryngeal mask 102; locating the monitoring devices on the laryngeal mask and/or the airway tube; and thereafter connecting the monitoring devices to the connector 118 (and/or the terminal 120 of the connector) via the wiring 116. The monitoring devices, the wiring, and/or the connector may be provided in a monitoring structure that is combined separately and then attached to the laryngeal mask and/or the airway tube to form the laryngeal mask airway.

The present disclosure further extends to a monitoring device and a connector that is suitable for installation on a laryngeal mask airway 100 as well as a kit of parts comprising a laryngeal mask airway, a monitoring device, and a connector. These components may be provided separately; typically two or more of these components are provided as a monitoring structure that can be fitted (or retrofitted) to a laryngeal mask airway. In particular, the monitoring device may be adapted to be embedded in an existing laryngeal mask airway and the connector 118 may be arranged so that it can be inserted into the airway tube 104 of an existing laryngeal mask airway so as to retrofit the monitoring structure to the laryngeal mask airway (and wiring may also be provided to attach the monitoring device to the connector).

Especially where the laryngeal mask airway 100 is manufactured in this way (but also otherwise), the monitoring devices and/or the monitoring structure may be removable from the remainder of the laryngeal mask airway so that maintenance can be performed on the components contained in the monitoring structure.

In differing embodiments, the wiring 116 and/or monitoring structure is arranged to be located internally to the airway tube 104 or externally to the airway tube. An internal fitting may be appropriate where the monitoring structure is intended to be retrofitted to an existing laryngeal mask airway, since in this situation the airway tube may have been designed with the contours of the throat in mind. VVhere the laryngeal mask airway is newly built it may be desirable to have the monitoring structure located external to the airway tube to simplify maintenance of the products (e.g. since this enables the monitoring structure to be more easily accessed) and -19 -in this situation the exterior of the monitoring structure may be shaped to contour to the shape of the throat.

In some embodiments, the laryngeal mask airway 100 is provided as a kit of parts that comprises a first component comprising the laryngeal mask 102 and the airway tube 104 and a second component comprising the monitoring device(s) and/or the monitoring structure. The wiring 116 may be provided as a separate component and/or as part of the second component. Similarly, the connector 118 may be provided as a separate component and/or as part of the first component and/or the second component.

In some embodiments, the monitoring devices are integral to the laryngeal mask airway 100 and manufacturing the laryngeal mask airway may involves forming the laryngeal mask, wherein the laryngeal mask extends around the monitoring devices.

Alternatives and modifications It will be understood that the present invention has been described above purely by way of example, and modifications of detail can be made within the scope of the invention.

For example, the operation of the laryngeal mask airway 100 may be dependent on whether the laryngeal mask airway is connected to an external device. In particular, when the laryngeal mask airway is not connected to an external device the monitoring devices may be arranged to draw power from a power supply of the laryngeal mask airway, and/or a user interface of the laryngeal mask airway may be arranged to provide an output, and/or the laryngeal mask airway may be arranged so that the user interface is useable to control the monitoring devices.

Conversely, when the laryngeal mask airway is connected to an external device, the monitoring devices may be arranged to draw power from the external device, and/or the user interface of the laryngeal mask airway may be arranged not to provide an output, and/or the laryngeal mask airway may be arranged so that the external device is useable to control the monitoring devices.

While the detailed description has primarily described a connector that receives a plug from an external device, it will be appreciated that more generally the connector may be in any form that enables a connection to be made to the external device. For example, the connector may comprise a plug that is arranged to connect to a socket of an external device.

Reference numerals appearing in the claims are by way of illustration only and shall have no limiting effect on the scope of the claims.

Claims

-20 -Claims 1 A laryngeal mask airway comprising: an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; a monitoring device located towards the first end of the laryngeal mask airway; and a connector located towards the second end of the laryngeal mask airway, wherein the connector comprises a communication interface for transmitting signals from the monitoring device to an external device.
2 The laryngeal mask airway of any preceding claim, wherein the connector further comprises a lumen for providing a gas to the airway tube of the laryngeal mask airway, preferably for providing a gas to the airway tube from the external device.
3. The laryngeal mask airway of claim 2, wherein the communication interface of the connector is located adjacent the lumen of the connector.
4 The laryngeal mask airway of any preceding claim, comprising a plurality of monitoring devices, preferably wherein the communication interface of the connector is arranged to transmit signals from each of the monitoring devices to the external device.
The laryngeal mask airway of claim 4, wherein two or more of the plurality of monitoring devices share componentry, preferably wherein two or more of the plurality of monitoring devices share a shared light emitting diode, more preferably wherein the light emitting diode is a part of a pulse oximeter and also a blood pressure monitor.
6. The laryngeal mask airway of any preceding claim, comprising a power source, preferably wherein the power source is arranged to provide power to the monitoring device.
7. The laryngeal mask airway of any preceding claim, comprising a user interface, preferably wherein the user interface is arranged to output a measurement from the monitoring device.
8 A laryngeal mask airway comprising: an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; a monitoring device located near the first end of the laryngeal mask airway; and -21 -a user interface near the second end of the laryngeal mask airway, wherein the user interface is arranged to output a measurement from the monitoring device.
9 The laryngeal mask airway of claim 7 or 8, wherein the user interface is arranged to output an oxygen saturation, preferably an oxygen saturation measured by a/the pulse oximeter of the laryngeal mask airway.
10. The laryngeal mask airway of any of claims 7 to 9, wherein the user interface is arranged to output measurements from a plurality of monitoring devices.
11 The laryngeal mask airway of any of claims 7 to 10, wherein the user interface is an integral part of the laryngeal mask airway
12. The laryngeal mask airway of any preceding claim, wherein the laryngeal mask airway comprises a laryngeal mask, preferably wherein the laryngeal mask is located at the first end of the laryngeal mask airway and/or wherein airway tube extends from the laryngeal mask to a second end of the laryngeal mask airway.
13. The laryngeal mask airway of claim 12, wherein the monitoring device is mounted on, and/or is integral to, the laryngeal mask.
14. The laryngeal mask airway of any preceding claim, wherein the monitoring device is located such that, in use, the monitoring device is adjacent to, and/or in contact with, the upper airway of a user.
The laryngeal mask airway of any preceding claim, comprising one or more of: a temperature sensor; a blood pressure monitor, preferably a photoplethsmography (PPG) blood pressure sensor; a pulse oximeter; two or more electrocardiogram electrodes; and a CO2 detector or tube to enable gas sampling for connection to an external CO2 detector.
16. The laryngeal mask airway of any preceding claim, comprising a first electrocardiogram electrode near the first end of the laryngeal mask airway and a second electrocardiogram electrode near the second end of the laryngeal mask airway, more preferably wherein, in -22 -use, the second electrocardiogram electrode is arranged to be in contact with the lips of a user.
17. The laryngeal mask airway of any preceding claim, comprising wiring to connect the monitoring device to the communication interface, preferably wherein the wiring is located adjacent, and/or aligned with, the airway tube.
18. The laryngeal mask airway of any preceding claim, wherein the communication interface is arranged to enable the external device to: output a measurement of the monitoring device; and/or provide power to the monitoring device; and/or control the monitoring device.
19 The laryngeal mask airway of any preceding claim, wherein the operation of the laryngeal mask airway is dependent on whether the laryngeal mask airway is connected to an external device, preferably wherein the monitoring device is arranged to draw power from a battery of the laryngeal mask airway when the laryngeal mask airway is not connected to an external device and/or wherein the monitoring device is arranged to draw power from an external device when the laryngeal mask airway is connected to an external device.
20. The laryngeal mask airway of any preceding claim, comprising a processor for: detecting a type and/or identity of an external device to which the laryngeal mask airway is connected; and/or processing signals received from the monitoring device before transmission to an external device.
21 A device arranged to interface with the laryngeal mask airway of any preceding claim, preferably wherein the device is arranged to provide a fluid to the airway tube of the laryngeal mask airway, more preferably wherein the device is arranged to provide a fluid to the airway tube of the laryngeal mask airway in dependence on the monitoring device of the laryngeal mask airway.
22. The device of claim 21 being a portable device.
23. A monitoring structure for fitting to a laryngeal mask airway, the monitoring structure comprising: a monitoring device arranged to monitor a vital sign of a user and a connector arranged to connect the laryngeal mask airway to an external device; wherein the -23 -connector comprises a communication interface for transmitting signals from the monitoring device to the external device.
24 A method of manufacturing a laryngeal mask airway, the method comprising: forming an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; locating a monitoring device at the first end of the laryngeal mask airway; and locating a connector at the second end of the laryngeal mask airway; wherein the connector comprises a communication interface for transmitting signals from the monitoring device to an external device.A kit of parts comprising: a laryngeal mask airway comprising an airway tube that extends from a first end of the laryngeal mask airway to a second end of the laryngeal mask airway; a monitoring device arranged to be mounted towards the first end of the laryngeal mask airway; and a connector arranged to be attached to the second end of the laryngeal mask airway, wherein the connector comprises a communication interface for transmitting signals from the monitoring device to an external device.