WO2023229471A1

WO2023229471A1 - A prehospital filter connectable to an airway management system

Info

Publication number: WO2023229471A1
Application number: PCT/NZ2022/050059
Authority: WO
Inventors: T'heniel CHETTY
Original assignee: Equippro Limited
Priority date: 2022-05-23
Filing date: 2022-05-23
Publication date: 2023-11-30

Abstract

Described herein is a prehospital air filter connectable to an airway management system. More specifically, an improved piece of medical equipment designed to be used by paramedics in a prehospital setting to save valuable time getting air into a patient's lungs. In particular, an apparatus for the facilitation of airway management during resuscitation suitable for protecting breathing equipment and measuring CO₂ output. The apparatus comprises an integrated filter and chamber having a connection to an ETCO₂/capnography device where the filter protects the equipment used for airway management from bodily fluids and aspiration from the patient and the capnography device samples the CO₂ present during ventilation and is displayed as a capnography graph on a cardiac monitor, and wherein the integrated filter and chamber reduces the dead space in the breathing circuit.

Description

A PREHOSPITAL AIR FILTER OR AIRWAY MANAGEMENT SYSTEM TECHNICAL FIELD Described herein is a prehospital air filter or airway management system. More specifically, an improved piece of medical equipment designed to be used by paramedics in a prehospital setting to save valuable time getting air into a patient’s lungs. In particular, an apparatus for the facilitation of airway management during resuscitation suitable for protecting breathing equipment and measuring CO₂ output. BACKGROUND ART Paramedics provide advanced life support to unresponsive patients. For example, they respond to stressful and unpredictable cardiac arrest emergencies filled with information they need to process. During cardiac arrest resuscitations, paramedics use various types of Airway Management equipment to provide oxygen to the patient. Airway Management equipment originated from the anaesthesiology department in the hospital. Consequently, the Airway Management equipment was not designed to suit the challenging and unpredictable pre-hospital setting. In particular, during cardiac arrest emergencies paramedics need to insert an airway device to ensure the patient receives oxygen. The airway management equipment used is dependent on the skills and experience of the paramedic. Airway management equipment ensures that the patient receives oxygen. During patient resuscitation, an advanced airway device such as a Laryngeal Mask Airway (LMA) or Endotracheal Tube (ETT) is inserted. Once a Laryngeal Mask Airway (LMA) or Endotracheal tube is inserted the paramedic then attaches four more pieces of equipment comprising the following: a filter, ETCO₂/capnography device, a Cobb’s connector, and Bag Valve Mask (BMV) before ventilation can occur. This combination allows paramedics to use the Bag Ventilation Mask (BVM) to maintain the ventilation rate for the patient. Maintaining a patient’s airway is vital as it impacts the outcome of the patient. Without sufficient oxygen, the patient may suffer neurological deficits and makes Airway management a time sensitive intervention. Studies have suggested that ventilation was less important within the first five minutes of a Cardiac arrest, and therefore, uninterrupted chest compressions take priority. This is because in adults, through chest compressions, there is blood circulating the body with some oxygen content. The airway device is inserted into the patient during the third cycle of CPR. Cardiac arrest is an example of when advanced airway devices are needed. During 2019-2020, New Zealand paramedics treated over 2000 cardiac arrest adult patients per year. Of those 2000 patients, only 13% had survived the cardiac arrest event once receiving treatment. Cardiac arrest is the most time- critical condition that paramedics respond to and patient outcomes are reliant on the initiation of CPR and the use of an Automated External Defibrillator (AED). As a result, the average response time for the ambulance service in an urban area is 8 minutes. Hence, a critical phase of responding to a cardiac arrest is advanced airway management by either using Endotracheal intubation or an LMA device. As aforementioned, Airway Management devices and accessories originate from the Anaesthesiology department in the hospital. These devices have been adapted for the prehospital setting where Anaesthesiologists also maintain a patients’ airway through using a variety of airway adjunct’s and Supraglottic devices. This equipment is also used in the prehospital environment by paramedics during emergencies. There are a variety of different Supraglottic devices, but the LMA and ETT are the most common ones used by paramedics in situations where an advanced airway is required. It is interesting to note that these devices are the same as the airway devices found in the hospital and that they have been designed for a completely different environment. It has been acknowledged that there are practical and clinical differences to the hospital environment and the prehospital setting. Studies on airway devices have mainly focussed on a hospital setting and there is a need for these types of studies to be conducted in the prehospital setting. For example, capnography technology has only been implemented for use in a prehospital setting since 2001. Furthermore, design research conducted in prehospital settings has only focused on stretchers, ambulance vehicles, and paramedic response bags. Currently, the filter and the capnography device are manufactured as separate devices and are connected together during a cardiac arrest (see for example Figures 1 and 2). The filter protects the equipment used for airway management from bodily fluids and aspiration from the patient. The capnography device samples theCO₂ present during ventilation and is displayed as a capnography graph on the cardiac monitor which helps paramedics determine whether the patient is going to deteriorate. It is a vital sign that helps paramedics determine the placement of an endotracheal tube. Capnography is also a good indicator of the effectiveness of chest compressions which also assists paramedics. This helps determine patient prognosis and gives paramedics more evidence to decide on whether CPR should be terminated. Also, it has been found that research conducted on resuscitation simulations have shown that the separate filter and capnography devices can be connected in the incorrect configuration (see for example, Figure 3). This is due to the universal ISO connectors that are standard to each piece of equipment. It allows the equipment to be attached in a certain way. It has been found that there are six possible combinations of the filter, ETCO₂/capnography device and Cobb’s Connector. As aforementioned, the standard ISO connectors allow the equipment to be connected incorrectly. Industry practice is to always connect the filter first as this protects the rest of the equipment. However, remembering the correct configuration when connecting the components can be challenging, especially when responding to a cognitively demanding emergency situation. A further disadvantage of the current configuration where the filter and capnography devices are separate leads to dead space within the breathing circuit. Dead space is when there is no gas exchange occurring (oxygen to carbon dioxide) which means the patient is not receiving any oxygen. This could lead to neurological impairment. This is especially an issue for paediatric cases as added connectors can increase this dead-space. Hence, the Cobb’s connector is not used in paediatric cases due to this increased dead space. Also, time can be wasted trying to connect the current solutions together as the connector pieces only fit one way (15 mm female and 22 mm male). As the capnography device is a separate component, it has been found that some paramedics can forget to attach this device due to it being placed in a separate bag to the other airway equipment. Another reason it is forgotten is because it is usually used as the ‘gold standard’ to determine tube placement for endotracheal tubes and is now being used for LMA insertion which does not require confirmation of placement. Forgetting to attach the capnography device delays the measurement of CO₂ which could impact patient outcomes. Therefore, from the above it would be useful to have an improved prehospital air filter system for enhanced airway management equipment or at least to provide the public with a useful choice. Further aspects and advantages of the prehospital air filter system and its usage will become apparent from the ensuing description that is given by way of example only. SUMMARY Described herein is a prehospital air filter or airway management system. More specifically, an improved piece of medical equipment designed to be used by paramedics in a prehospital setting to save valuable time getting air into a patient’s lungs. In particular, an apparatus for the facilitation of airway management during resuscitation suitable for protecting breathing equipment and measuring CO₂ output. In a first aspect there is provided an airway management apparatus for maintaining a patient’s airway comprising: at least one filter media for protecting the apparatus from bodily fluids and aspiration from the patient; and at least one ETCO₂/capnography device for connection to a cardiac monitor and for measuring and monitoring the CO₂ levels of a patient; wherein the at least one filter and capnography device are an integrated unit not requiring separate connection to each other, and wherein the integrated unit reduces a dead space to a breathing circuit of the airway management when there is no gas exchange of oxygen to carbon dioxide occurring of the patient. In a second aspect there is provided a method of maintaining a patient’s airway comprising the steps of: a) providing at least one filter for protecting the apparatus from bodily fluids and aspiration from the patient; b) providing at least one ETCO₂/capnography device for connection to a cardiac monitor and for measuring and monitoring the CO₂ levels of a patient; c) integrating the at least one filter and capnography device to form a unit thereby not requiring separate connection to each other, and wherein the integrated unit reduces a dead space to a breathing circuit of the airway management when there is no gas exchange of oxygen to carbon dioxide occurring of the patient; and d) connecting the unit to other airway management equipment. Advantages of the above include a filter that is always connected to the airway management system, thus protecting the breathing equipment. The airway management device also reduces the amount of time required to connect all of the pieces of equipment together which means the patient can be ventilated as soon as possible. During high performance CPR, the breathing tube is inserted during the third step of CPR and the paramedic waits for CPR to pause before ventilating the patient. They then have 2 minutes to assemble the equipment and can lose valuable time trying to connect the equipment as many incorrect combinations are possible when using the standard ISO connectors. In particular, this invention reduces time wasted through trying to connect the device as it only fits one way with connectors that are colour coded, including arrows communicating the direction of connection and having distinct letters. For example, the letters may be ‘A’ and ‘B’ which represent ‘Airway’ and ‘Breathing Circuit’. Also, if this combination is used during paramedic training, it will optimise assembling the equipment as it will become muscle memory. This invention also reduces the likelihood of a user forgetting to attach the capnography device. Paramedics sometimes forget to attach this device due to it being placed in a separate bag to the other airway equipment. Another reason it is forgotten is because it is usually used as the ‘gold standard’ to determine tube placement for endotracheal tubes and is now being used for LMA insertion which does not need confirmation of placement. Forgetting to attach the capnography device delays the measurement of CO₂ which could impact patient outcomes. As above, this invention eliminates this possibility as it is already integrated with the filter. The prior art systems with multiple separated connections add dead space to the breathing circuit. This invention reduces the amount of dead space present within the breathing circuit as it reduces two connector pieces (i.e. the separate capnography device). Dead space is when there is no gas exchange occurring (oxygen to carbon dioxide) which means the patient would not be receiving any oxygen. This could lead to neurological impairment. This is also an issue for paediatric cases as added connectors can increase this dead space. BRIEF DESCRIPTION OF THE DRAWINGS Further aspects of the apparatus, methods and uses thereof will become apparent from the following description that is given by way of example only and with reference to the accompanying drawings in which: Figure 1 illustrates an exemplary prior art filter device utilised by paramedics; Figure 2 illustrates an exemplary prior art ETCO₂/Capnography device used by paramedics; Figure 3 illustrates an exemplary prior art combination of connected equipment comprising a filter, ETCO₂ device/capnography and Cobb’s connector; Figure 4 illustrates an exploded view of an exemplary first embodiment of an unassembled airway management apparatus of the present invention; Figure 5 illustrates an exploded view of an exemplary second alternative embodiment of an unassembled airway management apparatus of the present invention; and Figure 6 illustrates a plan view of the exemplary second alternative embodiment of an assembled airway management apparatus of Figure 5; Figure 7 illustrates a close up exploded view of the exemplary second alternative embodiment of an assembled airway management apparatus of Figure 5; Figure 8 illustrates an exemplary lure sampling line that can be conceivably used with the airway management apparatus of the present invention; Figure 9 illustrates an exemplary embodiment of the assembled airway management system with a luer port for attachment of side streaming CO₂ devices; Figure 10 illustrates front perspective view of the exemplary second alternative embodiment of the assembled airway management system of the present invention; Figure 11 illustrates an exemplary patient resuscitation process of the assembled airway management system in use with typical componentry such as Bag Valve Mask, sampling lines connected to a cardiac monitor for CO₂ output measurement; and Figure 12 illustrates an exemplary patient resuscitation process of a prior art assembled airway management system in use with typical componentry such as Bag Valve Mask, sampling lines connected to a cardiac monitor for CO₂ output measurement. DETAILED DESCRIPTION As noted above, described herein is a prehospital air filter or airway management system. More specifically, an improved piece of medical equipment designed to be used by paramedics in a prehospital setting to save valuable time getting air into a patient’s lungs. In particular, an apparatus for the facilitation of airway management during resuscitation suitable for protecting breathing equipment and measuring CO₂ output. For the purposes of this specification, the term ‘about’ or ‘approximately’ and grammatical variations thereof mean a quantity, level, degree, value, number, frequency, percentage, dimension, size, amount, weight or length that varies by as much as 30, 25, 20, 15, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1% to a reference quantity, level, degree, value, number, frequency, percentage, dimension, size, amount, weight or length. The term ‘substantially’ or grammatical variations thereof refers to at least about 50%, for example 75%, 85%, 95% or 98%. The term 'comprise' and grammatical variations thereof shall have an inclusive meaning - i.e. that it will be taken to mean an inclusion of not only the listed components it directly references, but also other non-specified components or elements. The term Laryngeal Mask Airway (LMA) or grammatical variations thereof refers to an advanced breathing device that is often used by paramedics during patient resuscitation. The term Cobb’s Connector or catheter mount or grammatical variations thereof refers to a corrugated tube that is used to make it easier for a paramedic to ventilate a patient with one hand. The Bag Valve Mask (BVM) – see below, can be difficult to squeeze with one hand, so the Cobb’s connector helps the paramedic hold the BVM. The term Bag Valve Mask (BVM) or grammatical variations thereof is a device that is used to ventilate a patient. It is round and is connected to an oxygen tank. The term ETCO₂/Capnography device refers to an End-tidal Carbon dioxide measuring device. This device connects to the cardiac monitor to help measure CO₂. The term ‘integrated unit’ or grammatical variations thereof refers to the combining of a filter and a capnography device into one component and may simply be referred to throughout the specification as a ‘filtercap’. In a first aspect there is provided an airway management apparatus for maintaining a patient’s airway comprising: at least one filter media for protecting the apparatus from bodily fluids and aspiration from the patient; and at least one ETCO₂/capnography device for connection to a cardiac monitor and for measuring and monitoring the CO₂ levels of a patient; wherein the at least one filter and capnography device are an integrated unit not requiring separate connection to each other, and wherein the integrated unit reduces a dead space to a breathing circuit of the airway management when there is no gas exchange of oxygen to carbon dioxide occurring of the patient. The filter may protect the airway management equipment from bodily fluids and aspiration from the patient. In this way, the filter protects the BVM from cross contamination between patients. In this way, the integration of the filter and capnography device may ensure that every component after the filter (capnography device included) may be protected by the filter. This compares to the prior art configuration and systems, where it is still possible for the capnography device to be attached before the filter which could compromise the cardiac monitor, if the patient were to aspirate or excrete bodily fluids. This is because the capnography device is connected to the cardiac monitor which measures CO₂ output as well as heart rhythm. In preferred embodiments, the filter may be a high-efficiency particulate filter (HEPA) with a bacterial and viral efficiency of 99.99%. It should be appreciated by those skilled in the art that any type of filter could conceivably be used with this invention. However, it is envisaged that filters should meet the HEPA standard may satisfy certain levels of efficiency. For example, common standards require that a HEPA air filter must remove—from the air that passes through—at least 99.95% (ISO, European Standard) or 99.97% (ASME, U.S. DOE) of particles whose diameter is equal to 0.3 μm, with the filtration efficiency increasing for particle diameters both less than and greater than 0.3 μm. HEPA filters may capture pollen, dirt, dust, moisture, bacteria (0.2-2.0 μm), virus (0.02-0.3 μm), and submicron liquid aerosol (0.02-0.5 μm). Some microorganisms, for example, Aspergillus niger, Penicillium citrinum, Staphylococcus epidermidis, and Bacillus subtilis are captured by HEPA filters with photocatalytic oxidation (PCO). HEPA is also able to capture some viruses and bacteria which are ≤0.3 μm. The filter may comprise a luer lock port which may allow a side stream CO₂ sampling line to be utilised. However, this should not be seen as a limitation on the embodiments envisaged for this invention as in other embodiments an ETCO₂ device may be directly connected to the filter. The apparatus may comprise two moulds (a top half and a bottom half, also referred to herein as connector pieces). These connector pieces may be constructed using injection moulding methods known in the art and then ultrasonic welded together to form the filtercap. The connector pieces may be colour coded and have indicia such as arrows and/or letters communicating the correct direction of connection. The letters may be ‘A’ and ‘B’ which may represent ‘Airway’ and ‘Breathing Circuit’. In this way, if this is used during paramedic training, it will optimise assembling the equipment as it will become muscle memory. The end of the connector pieces may be dimensioned for 22 mm male/15 mm female – 15 mm female/22 male connections based on ISO standards. In one embodiment, one end of the connector piece may comprise a silicone band or be manufactured out of a softer material to communicate with the side of the filter that connects to an Laryngeal Mask Airway (LMA). In this way, the silicone is a soft material which may assist with communication on the patient side as it is soft like skin. Also, advantageously, paramedics may be able to feel the difference between both sides of the filter for correct orientation and direction for connection to the LMA. Therefore, it is envisaged that the filtercap may use both touch and visual aids to communicate with the patient side in use. It has been found by the inventor that the filtercap is approximately at least 40% faster to connect than other prior art systems. This is because the filtercap may act as a cognitive aid where users can quickly identify the connector which connects to the LMA, and thereby making it easier to remember the order of equipment that is connected after the LMA. This overcomes the problem of prior art systems as users may overturn the filter in order to connect to the required equipment, but inadvertently connect in the incorrect order. Furthermore, the use of the filtercap does not require a separate ETCO₂ device, thus again faster assembly as there is one less piece of equipment required to add to the breathing circuit. In preferred embodiments, the dead space within the breathing circuit may be reduced from approximately 10 – 25%, wherein the apparatus reduces the requirement of at least two connector pieces (as per prior art capnography devices) within the breathing circuit. It should be appreciated by those skilled in the art that dead space is when there is no gas exchange occurring (oxygen to carbon dioxide) which means the patient is not receiving any oxygen. Each connector piece on the breathing circuit creates dead space. As a result, paramedics are required to ensure the manual breath delivered is enough volume to cover the equipment dead space to avoid hypoventilation. This results in the rise of carbon dioxide in the blood stream and little oxygen which could lead to neurological impairment or death. This is an issue for paediatric and neonatal cases as added connectors can increase this dead space. Hence, the Cobb’s connector is not used in paediatric cases due to this increased dead space within the breathing circuit. Preferably, the apparatus may provide mechanical ventilation with a tidal volume range between 150 ml – 1200 ml to ensure adequate ventilation without causing trauma to the lungs. In a second aspect there is provided a method of maintaining a patient’s airway comprising the steps of: a) providing at least one filter for protecting the apparatus from bodily fluids and aspiration from the patient; b) providing at least one ETCO₂/capnography device for connection to a cardiac monitor and for measuring and monitoring the CO₂ levels of a patient; c) integrating the at least one filter and capnography device to form a unit thereby not requiring separate connection to each other, and wherein the integrated unit reduces a dead space to a breathing circuit of the airway management when there is no gas exchange of oxygen to carbon dioxide occurring of the patient; and d) connecting the unit to other airway management equipment. The embodiments described above may also be said broadly to consist in the parts, elements and features referred to or indicated in the specification of the application, individually or collectively, and any or all combinations of any two or more said parts, elements or features. Further, where specific integers are mentioned herein which have known equivalents in the art to which the embodiments relate, such known equivalents are deemed to be incorporated herein as if individually set forth. WORKING EXAMPLES The above described apparatus, methods and uses thereof are now described by reference to specific examples. EXAMPLE 1 With reference to Figure 4, an exploded view of an exemplary first embodiment of an unassembled airway management apparatus of the present invention is shown comprising a top half chamber 1, CO₂ sampling chamber 2, colour coded/letter coded 15 mm ISO connector 3, HEPA filter pad 4, bottom half chamber 5, bottom colour coded/letter coded 22 mm ISO connector 6 with silicone band and for connection with a PVC sampling line 7 and cardiac monitor connector plug 8. Figure 5 illustrates an exploded view of an exemplary second alternative embodiment of an unassembled airway management apparatus of Figure 6 with the same componentry, but with domed shaped top and bottom chambers 2 and 5 respectively. As is best shown in Figure 7, the apparatus comprises two moulds (a top half 2 and a bottom half 2, which are constructed using injection moulding methods known in the art and then ultrasonically welded together to form the assembled apparatus as best shown in Figures 5 and 10 and referred to herein as a filtercap. As above, the colour coded connectors 3 and 5 have indicia such as arrows and/or letters communicating the correct direction of connection. The letters of ‘A’ and ‘B’ represent ‘Airway’ and ‘Breathing Circuit’. In this way, if this is used during paramedic training, it will optimise assembling the equipment as it will become muscle memory. Also, one end of the connector, preferably the bottom chamber end 6 comprises a silicone band to communicate with the side of the filter that connects to an Laryngeal Mask Airway (LMA). In this way, the silicone is a soft material which assists with communication on the patient side as it is soft like skin. All airway equipment/anaesthetic equipment that are connected to ventilators use standard ISO connectors. As each end of the top and bottom chambers 1 and 5 utilise 22 mm male/15 mm female – 15 mm female/22 male connections are also based on ISO standards (to allow connection to standard airway equipment), the colour/letter codes along with the differing material type for each end of the chamber prevent the connection of incorrect components to each other in the breathing circuit. For example, although one end has an outer diameter of 22mm while the other end has an outer diameter of 15mm, the 22mm connector fits over the 15mm and the 15mm connector fits into the 22mm connector, each component can only be connected one way. However, without out colour/letter indicia codes, it is easy to connect each component in a different configuration as shown in Figure 3. The filter 4 protects the airway management equipment from bodily fluids and aspiration from the patient and is a high-efficiency particulate filter (HEPA) with a bacterial and viral efficiency of 99.99%. The airway apparatus includes a luer lock port (best seen in Figure 9) for connection with a luer line (Figure 8) to allow a side stream CO₂ sampling line to be utilised. EXAMPLE 2 Optimal Parameters for Airway Management Apparatus Relative to Exemplary Prior Art Systems Filtercap Optimal internal volume: 31-35 ml Optimal weight: 19g Bacterial efficiency :99.99% Viral efficiency: 99.99% Tidal Volume Range: 150 mL- 1200 mL Connectors: 22M/15F – 15F/ 22M (Based from manufacturer data)

Table 1: Dead space of an Exemplary Prior Art System

Table 2: Reduced dead space of Filtercap invention As shown above in Table 2, the dead space of 31 ml within the breathing circuit when using the filtercap is reduced by approximately 10%, compared to the prior art system (based on calculations of a LMA, filtercap, Cobb’s connector and BVM with a tidal volume of 500ml – see detailed calculations below). This is because the filtercap apparatus reduces the requirement of at least two connector pieces (as per prior art capnography devices) within the breathing circuit. It should be appreciated by those skilled in the art that dead space is when there is no gas exchange occurring (oxygen to carbon dioxide) which means the patient is not receiving any oxygen. Each connector piece on the breathing circuit creates dead space (best seen in Figure 11). As a result, paramedics are required to ensure the manual breath delivered is enough volume to cover the equipment dead space to avoid hypoventilation. This results in the rise of carbon dioxide in the blood stream and little oxygen which could lead to neurological impairment or death. This is an issue for paediatric and neonatal cases as added connectors can increase this dead-space. Hence, the Cobb’s connector is not used in paediatric cases due to this increased dead space within the breathing circuit. EXAMPLE 3 Model Calculations of Dead Space for Airway Management Apparatus (based on Figure 4 embodiment) Relative to Exemplary Prior Art Systems Equation Dead space is equal to the internal volume of the conducting airway. Exemplary Prior Art System (based on the manufacturer dead space values) LMA size 5- 30 mL ETCO₂- 6.6 mL Filter- 36 mL Cobb’s Connector- 20-40mL Total dead space volume = 112.6mL Filter cap dead space volume = 31mL (Exemplary prior art system dead-space – novel system with filtercap) / (total dead-space) x 100 (112.6-101)/ (112.6) x 100 = 10.30195382 = 10 % reduction of dead-space using new device Exemplary equation Exemplary Prior Art System LMA size 5 length = 187 mm Filter, ETCO₂, Cobb’s connector total length = 300 mm Total equipment length = 487 mm V= π/4 (d)²x l V= π/4 (0.015)² x 0.487= 8.61 x 10^-5 V= 86.1 mL System with Filtercap Invention LMA size 5 length =187 mm Filtercap and Cobb’s Connector length = 250 mm Total equipment length = 437 mm V= π/4 (d2)² x l V= π/4 (0.015)² x 0.437= 7.72 x 10^-5 V= 77.2 mL (Exemplary prior art system dead-space – novel system with filtercap) / (total dead space) x 100 (86.1-77.2)/86.1 x 100= 10.33681765 = 10% reduction in dead space Exemplary Equation Without Cobb’s Connector (Paediatric Use) Exemplary Prior Art System Paediatric LMA size 3 = 148 mm Filter Small = 64 mm ETCO₂= 55 mm Total = 267 mm V= π/4 (d2)²x l V= π/4 (0.015)² x 0.267= 4.72 x 10^-5 V= 47.2mL System with Filtercap Invention Paediatric LMA size 3 = 148 mm Filtercap= 70 mm Total= 218 mm V= π/4 (d2)² x l V= π/4 (0.015)² x 0.218= 3.85 x 10^-5 V= 38.5mL (Exemplary prior art system dead-space – novel system with filtercap) / (total dead-space) x 100 (47.2-38.5)/47.2x 100= 18.43220339 = 18% reduction in dead-space EXAMPLE 4 Operation of Airway Management Apparatus Relative to Exemplary Prior Art Systems With reference to Figure 11, an exemplary patient resuscitation process of the assembled airway management system in use is shown with typical componentry comprising Bag Valve Mask 1, Cobb’s connector/catheter mount 2, filtercap 3 and endotracheal tube 4 with sampling lines connected to a cardiac monitor for CO₂ output measurement. Once the components have been connected via the ISO 22 mm male/15 mm female – 15 mm female/22 male connections in known fashion, the BVM is squeezed manually (with one or two hands) to deliver ventilation to the patient. The air travels down the breathing circuit and into the patient’s lungs. Even though unconscious, the patient exhales gas which is what the ETCO₂/capnography device samples and measures. There is a chance of aspiration (vomiting or bodily fluids) which would go back through the breathing tube and up the circuit. However, the filter protects the equipment attached after it to protect the airway and also the cardiac monitor. An exemplary patient resuscitation process of a prior art assembled airway management system in use is shown in Figure 12 and operates as described above with a separate ETCO₂ device 3 and separate HEPA filter 4. This configuration contrasts with the invention where a filtercap 3 (Figure 11) is an integrated unit with ETCO₂/Capnography and filter functionality. Thus, advantageously the filtercap 3 eliminates the requirement for a separate ETCO₂/Capnography device and separate filter. Aspects of the present invention have been described by way of example only and it should be appreciated that modifications and additions may be made thereto without departing from the scope of the claims herein.

Claims

WHAT IS CLAIMED IS: 1. An airway management apparatus for maintaining a patient’s airway comprising: at least one filter media for protecting the apparatus from bodily fluids and aspiration from the patient; and at least one ETCO₂/capnography device for connection to a cardiac monitor and for measuring and monitoring the CO₂ levels of a patient; wherein the at least one filter and capnography device are an integrated unit not requiring separate connection to each other, and wherein the integrated unit reduces a dead space to a breathing circuit of the airway management when there is no gas exchange of oxygen to carbon dioxide occurring of the patient. 2. The airway management apparatus as claimed in claim 1, wherein the integration of the filter and capnography device protects a bag valve mask and components connected to the airway management equipment after the filter from bodily fluids and aspiration from the patient. 3. The airway management apparatus as claimed in claim 1 or claim 2, wherein, the filter is a high- efficiency particulate filter (HEPA) with a bacterial and viral efficiency of 99.99%. 4. The airway management apparatus as claim in any one of the preceding claims, wherein the filter comprises a luer lock port to allow a side stream CO₂ sampling line to be utilised. 5. Th airway management apparatus as claimed in any one of the preceding claims, wherein connector pieces are colour coded and have indicia such as arrows and/or letters communicating the correct direction of connection. 6. The airway management apparatus as claimed in claim 5, wherein the letters are ‘A’ and ‘B’ to represent ‘Airway’ and ‘Breathing Circuit’. 7. The airway management apparatus as claimed in claim 5, wherein the end of the connector pieces is dimensioned for 22 mm male/15 mm female – 15 mm female/22 male connections based on ISO standards. 8. The airway management apparatus as claimed in claims 5 to 7, wherein one end of the connector piece comprises a silicone band or manufactured out of softer material to communicate with the side of the filter that connects to an Laryngeal Mask Airway (LMA) to enable paramedics to feel the difference between both sides of the filter for correct orientation and direction for connection to the LMA. 9. The airway management apparatus as claimed in claim 8, wherein the apparatus utilises both touch and visual aids to communicate with a patient side in use. 10. The airway management apparatus as claimed in any one of the preceding claims, wherein the dead space within the breathing circuit is reduced from approximately 10 – 25%, and wherein the apparatus reduces the requirement of at least two connector pieces within the breathing circuit. 11. The airway management apparatus as claimed in anyone of the preceding claims, wherein the apparatus provides mechanical ventilation with a tidal volume range between 150 ml – 1200 ml to ensure adequate ventilation without causing trauma to the lungs. 12. A method of maintaining a patient’s airway comprising the steps of: a) providing at least one filter for protecting the apparatus from bodily fluids and aspiration from the patient; b) providing at least one ETCO₂/capnography device for connection to a cardiac monitor and for measuring and monitoring the CO₂ levels of a patient; c) integrating the at least one filter and capnography device to form a unit thereby not requiring separate connection to each other, and wherein the integrated unit reduces a dead space to a breathing circuit of the airway management when there is no gas exchange of oxygen to carbon dioxide occurring of the patient; and d) connecting the unit to other airway management equipment.