Abstract: Here is disclosed a regulator for diving free from any possibility that smooth operation of respective components might be obstructed due to the presence of impurities in the air supplied from an air cylinder. In the regulator, a tubular coupler member coupling a regulator for diving to an air hose extending from an air cylinder is provided with a filter assembly.

Abstract: Apparatus and method for providing breathing gases to a subject employs an exchanger taking up a quantity of a given component, such as CO2, from expiratory breathing gases passing through the exchanger and thereafter releasing the given component in inspiratory breathing gases subsequently passing through the exchanger. The exchanger may be selectively inserted in a flow path for the breathing gases for this purpose. Or, the breathing gases may be selectively passed through and bypassed around the exchanger. The apparatus and method may be used for non-invasive determination of the functional cardiac output of a patient using the differential form of the Fick equation.

Abstract: A compact and highly portable combination pressure swing adsorption apparatus and product gas conservation device for medical use, to produce efficiently a gas with a high concentration of oxygen and to deliver the oxygen concentrated gas to a user at selectable times and in selectable doses.

Abstract: An improved insufflation-exsufflation system with percussive assist for removal of broncho-pulmonary secretions includes a conduit for connection to a patient's airway; a pressure source for providing to the conduit alternating positive and negative pressure fluctuations at a first rate corresponding to patient insufflation-exsufflation; and a control mechanism for varying pressure during positive and negative pressure fluctuations at a second higher rate to periodically decrease the positive pressure during positive fluctuations and decrease the negative pressure during negative fluctuations to provide percussive pulses during at least one of insufflation-exsufflation to clear broncho-pulmonary secretions from the patient's airway.

Abstract: An improved trachea suction system includes a suction catheter with a high efficiency suction control valve providing unobstructed fluid flow in its activated suction applied mode for removal of viscous secretions at a low level of applied input suction through the catheter. The valve also non-restrictive to air flow at the distal tip of the catheter. The valve ideally part of a closed tracheal suction system having a catheter isolator seal with a vortex action catheter cleaning chamber located in front of the isolator seal which takes advantage of the high efficiency characteristics of the suction control valve.

Abstract: An apparatus and process for supplying low pressure oxygen-enriched gas to a patient and at a moderate pressure to a radial compressor, whereupon it is compressed and fed to a high pressure storage tank. The oxygen-enriched gas is prioritized so that it is continuously supplied via a patient flow line to the patient.

Abstract: A device for exchanging gas volumes in an anesthetic system has an inlet, an outlet, a first chamber arranged between the inlet and the outlet, a second chamber arranged between the inlet and the outlet, a switching valve for selective connection to the first chamber or the second chamber for forming a flow path between the inlet and the outlet, and a controller for controlling the switching valve.

Abstract: An improved insufflation-exsufflation system for removal of broncho-pulmonary secretions with automatic triggering of inhalation phase includes a conduit for connection to a patient's airway; a pressure source with a positive pressure port and a negative pressure port; a switching device selectively connecting the conduit to the positive pressure port, the negative pressure port and the dwell port; the sensor system for sensing an inhalation by the patient; and a controller system for driving the switching device to connect the conduits sequentially to the positive port, the negative port and the dwell port and to return again to the positive port in response to the sensor system sensing an inhalation by the patient while the conduit is connected to the dwell port.

Abstract: Self-contained underwater re-breathing apparatus having a breathing circuit, an injection system for adding fresh breathable gas to the breathing circuit, and an automatic control system including a microcomputer for monitoring physical parameters in the breathing circuit and controlling the feeding of breathable gas to the breathing circuit in accordance with said physical parameters. The re-breathing apparatus has a bailout system automatically activated in an emergency, where the breathing circuit is shut off, and the diver starts inhaling directly from the breathable gas supply and exaling to the environment. With the system of the invention, a part of the existing closed circuit is used for bailout, and no separate bailout circuit is provided. Therefore, there is no need to incorporate in the mouthpiece means for switching from one breathing circuit to another, and the mouthpiece can be kept smaller and simpler.

Abstract: An apparatus for reversing inhaled anesthesia, which is configured to be positioned along a breathing circuit or anesthesia delivery circuit, includes a filter for removing one or more anesthetic agents from gases passing therethrough, as well as a component for elevating CO2 levels in gases that are to be inhaled by an individual. The apparatus is configured to be positioned between a Y-connector of the breathing circuit and the portion of the breathing circuit that interfaces with the individual. The CO2 level-elevating component facilitates an increase in the ventilation of the individual without resulting in a significant decrease in the individual's PaCO2 level and, thus, a decrease in the rate at which blood flows through the individual's brain. A method of reversing the effects of inhaled anesthesia includes increasing the rate of ventilation of an anesthetized individual while causing the individual to inhale gases with elevated amounts of CO2 and while filtering anesthetic agents from such gases.

Abstract: An apparatus and process for supplying low pressure oxygen-enriched gas to a patient and at a moderate pressure to a radial compressor, whereupon it is compressed and fed to a high pressure storage tank. The oxygen-enriched gas is prioritized so that it is continuously supplied via a patient flow line to the patient.

Abstract: A life support system has a semi-closed rebreather supplying oxygen for multiple users, such as high altitude parachutists. A first tank supplies oxygen to initially purge the system, and a second, larger tank supplies oxygen at prescribed amounts for the duration of a mission. Users are connected by hoses to an inlet hose manifold on a scrubber body of the rebreather. The inlet hose manifold has an inlet port boss to receive exhaled gas from each user and an overpressure valve vents excessive amounts of exhaled gas. A CO2 absorbent in the scrubber body scrubs CO2 from the exhaled gas. An outlet hose manifold is connected to the scrubber body and has an inlet fitting to supply oxygen and at least one outlet port boss to feed the oxygen and the CO2 scrubbed gas to the users. This reliable system is lighter-weight and smaller than contemporary systems.

Abstract: A personal containment system includes a generally fluid-tight barrier and a powered air delivery system. The blower is generally isolated from the outer environment and draws purified air from a filter in fluid communication with the blower and generally located outside the containment system. A sealed port between the blower and filter provides a generally fluid tight connection to the barrier and blower during filter replacement. Leakage of contaminants into the system is minimized, and limited to materials that might enter the blower inlet. The blower inlet remains accessible during filter replacement, thereby speeding and simplifying the filter replacement process.

Abstract: A first and second housing joined together and rotatable with respect to each other, each housing having a conduit integral with an exterior wall, the conduits each having passageways leading to an internal portion of the respective housings. An internal edge of each housing mounts a heat-moisture exchange material having a transverse opening axially aligned with the passageway of the closest conduit. The passageway in the respective conduits are offset permitting passage of air to and from the patient through the heat-moisture material. The housings are rotated with respect to each other to axially align the passageways in the two conduits to permit passage of aerosol medicine through the exchanger without passing through the heat-moisture material.

Abstract: A method of making thin-walled permeable tubing using air blown extrusion, and of using the tubing in a device which enables a substantial humidification or drying of patient breathing gases in the breathing lines for patient monitoring or anesthesia results in cost savings and increased efficiency.

Abstract: The breathing system includes an annular filtration unit having apertures opening radially through inner and outer walls thereof, a central passageway and filtration material between the walls. The filtration unit is disposed in a canister containing a hood, a mouthpiece, a closure and an annular filter in the annular space between the filtration unit and the wall of the canister. Upon removal of the closure, the hood and mouthpieces are deployed and the hood is drawn about an individual's head through an opening in the hood. With the mouthpiece in the individual's mouth, ambient air from a toxic gas or smoke-filled environment is drawn into the canister through the annular filter, and passes radially inwardly through the filtration unit into the central passageway, where the filtered air reverses direction for flow axially into the mouthpiece such that the individual may breathe filtered air. Exhaled air passes into the hood and out through the hood opening.

Abstract: Apparatus and method for providing breathing gases to a subject employs an exchanger taking up a quantity of a given component, such as CO2, from expiratory breathing gases passing through the exchanger and thereafter releasing the given component in inspiratory breathing gases subsequently passing through the exchanger. The exchanger may be selectively inserted in a flow path for the breathing gases for this purpose. Or, the breathing gases may be selectively passed through and bypassed around the exchanger. The apparatus and method may be used for non-invasive determination of the functional cardiac output of a patient using the differential form of the Fick equation.

Abstract: A civilian anti-terrorist attack gas mask used as an emergency measure to remove hazardous air pollutants present in air drawn from an ambient atmosphere to provide a person with suitably breathable air is provided in the form of a cap fitted over the person's head and carrying a hood draped over the person's head to establish a chamber contiguous with the person's face, the gas mask including an impeller assembly placed in a peak on the cap for drawing air from the ambient atmosphere through an adsorption element and a filter element to circulate fresh breathable air through the chamber, the impeller assembly maintaining an air pressure in the chamber raised above the ambient air pressure.

Abstract: A tube for use in an anesthetic system has an essentially cylindrical housing. More effective take-up of carbon dioxide is achieved by an absorbent for carbon dioxide that is arranged within the tube.

Abstract: A system for removing halocarbon gas components from waste anesthetic gases using the resource of cold oxygen from liquid oxygen which is stored cryogenically at a healthcare facility. The oxygen is warmed while cooling of waste anesthetic gases from anesthetizing locations of a healthcare facility. Two heat exchangers/condensers are provided. In the first, the waste gas is cooled to about 0° C. thereby condensing any water vapor in the waste gas. In the second, the waste gas is further cooled to about −150° C. thereby condensing and liquefying the halocarbon gas components, which are removed to a tank for recycling and/or destruction. The remainder of the waste gases (e.g., nitrogen, oxygen and nitrous oxide) are vented to the atmosphere. The warmed oxygen is piped to the healthcare facility for its normal uses after it has been warmed by the waste anesthetic gases in the two heat exchangers/condensers.

Abstract: The present invention is directed to a gas sampling system for conducting respiratory gases from a patient respiratory gas output mechanism to a respiratory gas monitoring device. The respiratory gas monitoring device is equipped with a monitor input connector. The gas sampling system includes an input connector configured to couple the gas sampling system to the patient respiratory gas output mechanism. A gas sampling tube is coupled to the input connector. The gas sampling tube is configured to conduct the respiratory gases from the patient to the gas monitoring device. An output connector couples the gas sampling tube to the monitor input connector. An output dryer tube is coupled between the gas sampling tube and the output connector. The output dryer tube is characterized by a tube length and a relative moisture removal efficiency. The relative moisture removal efficiency is dependent on the tube length.

Abstract: This Personal Respirator is a respiratory protection air-purifying device. It minimizes the area required in front of the face, especially around the mouth area, by locating the heavier filter cartridge behind the head, resting on the lower neck and shoulders, connected by two filtered air tubes around the head and neck partially counterbalancing the valve chamber directly in front of the mouthpiece, forming a ring around the head with the mouthpiece in the mouth and the exhaust port in the bottom of the valve chamber. The valve chamber has the filtered air intake check type valves opposite each other horizontally, an exhaust check type valve down with short exhaust tube and an oval mouthpiece tube passing through the mouthpiece, into the mouth. The valve chamber is of minimal size with the three check valves and mouthpiece close together thus minimizing the internal dead air space and making the outside dimensions small enough to fit under safety equipment.

Abstract: A rechargeable breathing apparatus is disclosed including a closed breathing system for receiving exhaled air containing a CO2 adsorber for the inhaled air, a breathing bellows for receiving the inhaled air and delivery of the breathing air, and an oxygen accumulator connected to the breathing bellows and containing a reversably oxygen fixating agent and being rechargeable by bringing that agent into reaction with oxygen or air so that oxygen is fixated thereto. In one apparatus there is included a pressurized gas container and a hydrostatic valve for cooperation between the breathing bellows and the pressurized gas container.

Abstract: An isolation device is disclosed. The isolation device may have a movable partition and a housing disposed about the movable partition. The isolation device may have a partition biaser joined to the partition, and a CO2 scrubber. A method of delivering inspiratory gas to a patient is also disclosed.

Abstract: The present invention is directed to a portable oxygen concentrator system adapted to be transported by a user. The portable oxygen concentrator system includes an energy source, an air separation device powered by the energy source and adapted to convert ambient air into concentrated oxygen gas for the user, at least one sensor adapted to sense one or more conditions indicative of the oxygen gas needs of the user, and a control unit interrelated with the air separation device and the at least one sensor to control the air separation device so as to supply an amount of oxygen gas equivalent to the oxygen gas needs of the user based at least in part upon the one or more conditions sensed by the at least one sensor.

Abstract: A moisture sump integrated into a carbon dioxide absorber canister provides a collection reservoir for condensate from a patient ventilator system when the carbon dioxide absorber canister is attached to the ventilator system. The volume of the moisture sump is appropriately sized so that the time interval required to collect a maximum amount of condensate interval is not more than the life expectancy of the carbon dioxide absorbing material contained within the canister. The moisture sump allows condensate management of difficult to drain areas such as the inlet to the expiratory check valve of a ventilator system. The removal of the carbon dioxide absorber canister by a patient attendee to replace the carbon dioxide absorbing material ensures that the condensate collected by the integral moisture sump is eliminated from the patient ventilator system.

Abstract: A filter for a respiratory circuit has a housing with an inlet port and an outlet port for connection to respective breathing tubes. A gases space lies between the inlet and outlet ports and gases pass across the gases space from the inlet port to the outlet port in use. A filter media spans the gases space, dividing the gases space into an inlet chamber and an outlet chamber. Gases passing from the inlet port to the outlet port pass through the filter media. A surrounding outer wall surrounds the housing apart from the inlet port and outlet port and is spaced from the wall of the housing. One or more air pockets are created between the outer wall and the housing. The air pockets insulate the housing from ambient conditions.

Abstract: A system 10 is provided for automatically evacuating a water trap 50 of a ventilator 20. The ventilator 20 delivers air through a humidifying water heater 30 and along an air supply line 40 to a patient requiring breathing assistance. A dip 44 in the air supply line 40 is configured with a water trap 50 for collecting condensate within the air supply line 40. A suction line 60 is located within the water trap 50 at a tip 62 and has an end 68 outside of the water trap 50 which is coupled to a canister 70. The canister 70 is also coupled to a vacuum source 100 through a valve 80. When the valve 80 is in a first open position, the vacuum source 100 provides suction along the suction line 60 so that liquids collecting within the water trap 50 are evacuated out of the water trap 50 and delivered into the canister 70. A controller 90 controls the frequency with which the valve 80 is opened and a duration for which the valve 80 remains in the opened position.

Abstract: An endotracheal suction catheter apparatus is provided. The apparatus includes a distal end that is configured for allowing a catheter to be moved through the distal end and into the respiratory tract of a patient. The distal end defines a cleaning chamber where the catheter may be cleaned. A flap is located in the distal end and is located on one end of the cleaning chamber. The flap effects fluid flow within the cleaning chamber during cleaning of the catheter. A connection member is present and is attached to the distal end. The connection member is configured for releasably engaging a heat and moisture exchanger so that the catheter may be advanced through the distal end into the heat and moisture exchanger.

Abstract: The present invention relates to a fan-forced positive pressure breathing apparatus commonly known as a Powered Air Purifying Respirators (PAPR) system, and specifically concerns the connecting of the breathing components of such equipment. The invention is a method and apparatus for rapid engagement of PAPR breathing components (such as air supply lines and filter elements to a blower housing). The invention also provides for indicating and/or monitoring whether the relative components have been aligned and coupled in sealed engagement.

Abstract: A rechargeable breathing apparatus is disclosed including a closed breathing system for receiving exhaled air containing a CO2 adsorber for the inhaled air, a breathing bellows for receiving the inhaled air and delivery of the breathing air, and an oxygen accumulator connected to the breathing bellows and containing a reversably oxygen fixating agent and being rechargeable by bringing that agent into reaction with oxygen or air so that oxygen is fixated thereto. In one apparatus there is included a pressurized gas container and a hydrostatic valve for cooperation between the breathing bellows and the pressurized gas container.

Abstract: A multilumen filter device has a housing with first and second filter chambers, each chamber in fluid communication with a separate distal and proximal fluid path. The filter device may be used to provide respiratory gases to and receive expiratory gases from a patient connected to a unilimb respiratory circuit. The filter device may also serve as a connector for respiratory circuit components, and have fasteners or blocking devices at either or both of its distal and proximal ends.

Abstract: A heat-moisture exchanger (HME) and nebulization device for connection to a mechanical ventilator or anesthesia apparatus, to provide humidification or an aerosolized medication without disconnection of the HME from the ventilator circuit, a respiratory device comprising a first housing having an output fitting to provide a connection to an artificial airway of a patient, and a rotatable second housing connected to the first housing, having an input fitting to provide a connection to a ventilator circuit, the input fitting, and the output fitting are in communication with a primary gas flow, the first housing is partitioned into at least two chambers, a chamber to provide an enclosure for an absorbent material, and a chamber to provide a passageway for conveyance of an aerosol, the second housing to provide an enclosure for a nebulizer having a reservoir for a liquid medication, an instillation port to inject the liquid medication, interior to the chamber or passageway, a reciprocating member to open and clos

Abstract: A portable bag valve mask resuscitator including an air intake adapter for attachment of an air filter cartridge for filtering air administered during manual resuscitation procedures and a method for converting bag mask resuscitators.

Abstract: An oxygen dispenser for dispensing substantially pure oxygen or highly oxygen enriched air. The dispenser has an oxygen concentrator or an oxygen/oxygen-enriched air-containing cylinder in fluid communicatin with a dispenser outlet via pipework, a flow control valve to control flow of oxygen or oxygen-enriched air to the dispenser outlet, the flow control valve being under the control of a controller. The dispenser unit further having a card reader for a mag-stripe, swipe card, smart card or similar or a receiver for credit tokens or other data credit input mechanisms whereby credit units may be input to the dispenser controller to dispense oxygen or oxygen enriched air.

Abstract: A breathing circuit of the closed circuit type has improved means for removing water vapor to prevent condensation within the circuit. A dryer is placed in the breathing circuit, downstream of the CO2 absorber, for removing water vapor from the breathing gases, including that entrained in the breathing gases during passage through the CO2 absorber. The dryer may utilize a thermoelectric cooling element or a water vapor permeable membrane.

Abstract: A device for recovering anaesthetic. During the administration of inhaled anaesthetic, the device is connected to a patient. It includes an anaesthetic evaporator for supplying anaesthetic to the patient and an absorption filter for absorption and desorption of the medium. The device includes a body placed between the absorption filter and the patient with the gases breathed by the patient passing across the body and the anaesthetic evaporating on the surface thereof. The absorption filter is in the form of a flat element placed in the flow path of a gas breathed by the patient and contains fibers of active carbon. The absorption filter is movably arranged in a housing between a position in which substantially all the gases breathed pass through the filter and the position in which a small portion of the gases breathed passes therethrough.

Abstract: A breathing apparatus (10) including a mouthpiece (13) and a carbon dioxide removal area (18) disposed between the mouthpiece and an air reservoir chamber (19). The chamber is preferably filled with a foam material (27) and is further in communication with ambient air (29) to enable mixing with expired air within the chamber (19). The breathing apparatus (10) is useful for simulating the lower partial pressure of oxygen at high altitude, hence it may be used by athletes for simulating “living at altitude”.

Abstract: A closed circuit is provided in which tube connected to the patient's mouth is connected directly or via a connection tube to a heat-moisture exchanger which, in turn, is connected to the feed and the discharge, respectively, of the respirator. A moisture-removing device is arranged in the feed or discharge.

Abstract: The present invention allows a low-flow anesthesia method to be executed while hindering temperature increases in a carbon dioxide absorbent, thereby reducing evaporation of water from the carbon dioxide absorbent and the amount of condensation formed in an anesthetic circuit, but without increasing the amount of decomposed compounds.

Abstract: A negative pressure respirator 20′ that has an integrally-disposed filter element 28 and that covers at least the nose and mouth of a wearer. The respirator 20′ includes an exhalation valve 22 and an impactor element 50 that covers the exhalation valve 22. The exhalation valve 22 has a diaphragm and an orifice and opens in response to increased pressure when the wearer exhales to allow exhaled air to be rapidly purged from the mask interior. The impactor element 50 is positioned in the exhale flow stream to remove particles and other contaminants from the exhaled air. The exhalation valve and impactor element have a ratio of Zn:Dj of less than about 5.

Abstract: An apparatus for supplying a breathing gas to a patient has a gas supply for generating a flow of breathable gas during an inspiration and an expiration phase of a patient breathing cycle. An inspiration line is provided having an inlet through which a flow of breathing gas from the supply can pass as well as an expiration line through which an expiration gas from the patient can flow. A flow controller is provided for selecting, during an inspiration phase, a first flow path for gas from the supply into the inlet and for selecting, during the expiration phase, a second flow path for gas from the supply in a direction across a venturi outlet of the expiration line, to enhance removal of expiration gas therefrom by venturi suction.

Abstract: A closed circuit breathing apparatus comprising: a container containing a reactant for reacting with carbon dioxide and water to produce oxygen gas; a housing for the container; a foldable breathing bag and breathing tube assembly, including a mouthpiece disposed on the breathing bag, in gas-flow communication with the container; a cover for containing the folded breathing bag and breathing tube assembly; a strap for removably securing the cover onto the apparatus; and a chlorate candle for providing an initial volume of oxygen gas to the breathing bag wherein the breathing bag and breathing tube assembly is unfolded and the chlorate candle automatically fired by a user donning the mouthpiece.

Abstract: Apparatus for treating respiratory gases include a housing having a patient side port adapted for connection to a tracheal tube device and a machine side port adapted for connection to a tube for passing respiratory gases; and one or more liquid trap chambers positioned between the patient side and machine side ports and adapted to receive and hold liquid passed from outside the housing through the patient side and machine side ports.

Abstract: The avalanche survival pack assembly includes 1) a main support chest pack assembly to be secured as by a waist support assembly and a shoulder harness assembly to a user thereof; 2) an oxygen supply assembly or means to provide oxygen through a nose/mouth mask assembly to be worn by an avalanche victim and placed in operation on initially observing being caught up within an avalanche condition; 3) an auxiliary power supply assembly to provide electrical battery power to an oxygen conserving assembly or means and a radio signal transmit beacon assembly or means; 4) the radio signal transmit beacon assembly to transmit a radio signal therefrom for aiding in locating the avalanche victim by avalanche rescuers; 5) a visual location indicator assembly having a lengthy, brightly colored ribbon-like material and having one end connected to the main support chest pack assembly and the other end to be trailed outwardly hoping to be exposed on a top surface of the avalanche snow pack; and 6) a control circuit assembly

Abstract: A method is disclosed for providing a pure gas for use medical procedures in which the gas is contaminated with other gases during the procedure, and then separating the contaminants and recovering and reusing the decontaminated gas. The method is most advantageously used in medical imaging processes, such as magnetic resonance image (MRI), where hyperpolarized image enhancing noble gases, notably He3 or Xe129, are used for image enhancement in brain and lung imaging, and in which the contaminants are normally the exhalant gases from the imaged patient. The contaminated gas is passed through a series of drying and purification steps to remove the exhalant gases and separate the gas. The purified gas is then recovered and stored for reuse. This system prevents the loss of significant amounts of the image enhancing gases, which is important since key gases such as He3 and Xe129 are rare and expensive, and (especially He3) permanently lost once vented.

Abstract: A catheter mount incorporates a filter pleated along its length in zig-zag fashion. Opposite edges of the filter are sealed between identical upper and lower parts of a housing between teeth extending along opposite sides.

Abstract: The present invention called a patient ventilator oxygen concentration system advantageously utilizes an existing suitable air supply and provides a modular oxygen concentrator that uses the existing air supply and a medical grade air filtration package for providing medical grade using the existing air supply. The oxygen concentrator has multiple bed pairs which can be selectively activated. If one of the multiple bed pairs is not activated, the excess air provided by the existing air supply is filtered and medical grade air is supplied instead of oxygen gas for use with patient ventilators. Advantageously, the present invention obtains a large increase in medical grade air flow at the expense of very little oxygen flow while maintaining oxygen purity using the existing air supply. The present invention provides a pneumatic circuit which is capable due to a modular bed design. Each bed pair uses approximately three SCFM (80 SLPM) to produce five SLPM of oxygen.

Abstract: A medical gas utility stand for connection to at least one remote medical gas source, each medical gas source detachably connectable to a gas conduit line so that the gas conduit line is in fluid communication with one medical gas source. The gas utility stand includes a base connected to a substantially upright support member. The gas utility stand also includes a gas connection member having at least one gas conduit defining a gas passage extending between an input end and an output end, the gas connection member fixedly connected to the support member adjacent its top end. Additionally, the gas utility stand has at least one pair of identical gas fittings, each gas fitting defining a bore extending between an attachment end and a securing end, the securing ends of one pair of identical gas fittings detachably secured to the opposing input end and output end of one gas conduit so that the bores of the pair of identical gas fittings are in communication with the gas passage of the gas conduit.

Abstract: Apparatus for heating and humidifying respiratory gases include a housing, a filter element located in the housing, and a gas permeable member positioned in the housing to exchange heat and moisture with respiratory gases passing through the housing. In one embodiment, the inlet portion of the housing is detachably secured to the remainder of the housing and is adapted to be replaced, together with the filter element, while the outlet portion of the housing remains connected to the tube for passing respiratory gases. Additional materials, such as generating material useful to produce moisture and heat and heat generating materials useful to generate heat may be included within the housing. The present apparatus are particularly structured and adapted to reduce the risk of causing trauma to the patient and to increase the safety and comfort of the patient using such apparatus.