Abstract: A multiple stage variable speed blower for Continuous Positive Airway Pressure (CPAP) ventilation of patients includes two impellers in the gas flow path that cooperatively pressurize gas to desired pressure and flow characteristics. Thus, the multiple stage blower can provide faster pressure response and desired flow characteristics over a narrower range of motor speeds, resulting in greater reliability and less acoustic noise.

Abstract: A vacuum demand valve for controlling flow of exhalation gases from a patient to a vacuum line. The demand valve comprises: a housing having a housing inlet that allows exhalation gases to flow into the housing from a patient, and a housing outlet that allows gases to flow from the housing into the vacuum line; a diaphragm having a flexible skirt and a rigid portion moveable in response to gas pressure in the housing; a sealing member connected to the rigid portion to engage the housing outlet to resist the flow of gases from the housing to the vacuum line. In a first condition, the vacuum line pressure causes the sealing member to engage the housing outlet and in a second condition a predetermined pressure of exhalation gases in the housing causes the sealing member to disengage from the housing outlet.

Abstract: An exhalation breath-actuated nasal deliver device for and a method of delivering a substance to a nasal cavity of a subject, the delivery device comprising: a nosepiece for fitting to a nostril of a subject; a mouthpiece through which the subject in use exhales; and delivery unit, as one of a mechanical delivery pump or a nebulizer, for delivering a substance to the nosepiece; and an actuation mechanism for actuating the delivery unit in response to oral exhalation through the mouthpiece, and preferably when at least one or both of the pressure at or the flow rate through the nosepiece exceeds a predetermined threshold.

Abstract: Oxygen breathing masks, as well as methods of providing oxygen to persons, are detailed. The devices may include mechanisms for supplying either oxygen or ambient air to a person depending on inspiration pressure applied by the person to a first volume to which the person's mouth and/or nose is connected.

Abstract: A system for circuit compliance compensated volume assurance pressure control in a patient respiratory ventilation circuit, having a patient circuit volume estimator for estimating a patient circuit compliance, a patient circuit volume estimator to estimate a circuit volume VOLCKT—EST based on the patient circuit compliance, a patient volume observer, for estimating a patient volume VOLTID—EST based on a measure delivered net volume VOLNET and the patient circuit compliance, a volume assurance controller for generating a circuit compliance volume compensation factor VOLTID—CTL based on a preset assured volume VOLASS—SET and the estimated patient volume VOLTID—EST, and a decelerating inspiratory flow controller, operative to generate a decelerating inspiratory peak flow based on a preset inspiratory time TINSP and the volume compensation factor VOLTID—CTL.

Abstract: The invention relates to a breathing assistance device for a patient (P), the device including: —a source of respiratory pressurized gas (S), a gas transmission duct (31) comprising a distal end (31d) coupled to said source and a proximal end (31p) coupled to the patient, —a gas regulating valve (32, 50) interposed in the gas transmission duct at a proximal location, comprising a leakage orifice (531) and an obstruction means (54) capable of varying the opening of the leakage orifice upon signal of controlling means (35) and allowing a bidirectional gas flow through the leakage orifice in both expiration and inspiration phases.

Abstract: A pressure activated device for controlling the supply of a gas and a breathing system for underwater use incorporating the device are provided. The device comprises an input port (64) for connection to a pressurised gas supply, an output port (66), a chamber (62) and a pressure monitoring port (66). Flow control means are provided for selectively opening a fluid path (65) outside the chamber between the input port and the output port when the ambient pressure is higher than the pressure in the chamber by a more predetermined amount. Reset means (80) selectively open a fluid path (84, 92) between the pressure monitoring port and the chamber, when the pressure at the pressure monitoring port is higher than the ambient pressure by more than a predetermined amount. The device may be used to control the supply of diluent gas to an underwater breathing system, or to maintain the volume of a flexible enclosure substantially constant, irrespective of variations in the ambient pressure.

Abstract: A system and a method for circuit compliance compensated pressure control in a patient respiratory ventilation system, having a pressure regulated feedback servo control loop, a pressure-regulated volume controller, and a patient volume observer. The patient volume observer is operative to estimate a patient volume, that is, the volume actually delivered to the patient by accounting for volume deviation or loss caused by patient circuit leakage and valve dynamics. Based on the difference between the estimated patient volume and a set tidal volume, the pressure-regulated volume controller is operative to generate and update a circuit compliance pressure compensation factor. The pressure regulated feedback servo control loop is operative to modulate the peak airway pressure based on the circuit compliance pressure compensation factor, so as to achieve the set tidal volume while maintaining a constant inspiratory time and a constant I:E ratio.

Abstract: A medical breathing apparatus incorporating a regulator for supplying breathing gas to a patient from an air hose (11). The regulator supplies breathing gas on demand to the patient via a mouthpiece or similar attached to an output connector (55). The connector forms part of a removable output unit (4) incorporating a filter (53) and an exhale flap valve (57/58) on the patient side of the filter. When the patient exhales, exhaled gas entering the connector (55) exits to atmosphere via the exhale valve without passing through the filter into the interior of the regulator, thus reducing cross-contamination between patients. Also described is an improved valve seat (16)/valve member (18) assembly in which multiple spaced pivot points (22, 23) are defined to cause the mechanical advantage for operating the valve member to reduce as the valve opens, thus reducing the force needed to operate the valve at lower flow rates.

Abstract: A ventilator device delivers ventilatory support to a patient in a back up timed mode when patient respiration is not detected or a spontaneous mode when patient respiration is detected. The timing threshold governing the back-up mode is chosen to deviate from normal expected respiration time for the patient to promote patient initiated ventilation in the spontaneous mode but permit back-up ventilation in the event of apnea. Automated adjustments to the timing threshold during the timed mode are made from the less vigilant timing threshold to a more vigilant threshold at or near a timing of normal expected breathing of the patient. Such adjustments may be made from a minimum to a maximum vigilance timing settings or incrementally there between as a function of time in the timed mode which is preferably the number of delivered machine breaths.

Abstract: Several methods and a system for a method and system of safeguarding a filling process of a breathable air apparatus are disclosed. In one embodiment, a method of safety of a building structure includes safeguarding a filling process of a breathable air apparatus by enclosing the breathable air apparatus in a secure chamber of a fill site of the emergency support system of the building structure to provide a safe placement to supply the breathable air to the breathable air apparatus. The method may include ensuring that a prescribed pressure of the emergency support system maintains within a threshold range of the prescribed pressure by including a valve of the emergency support system to prevent leakage of breathable air from the emergency support system.

Abstract: A method and system for controlling fluid flow settings by receiving a precondition pressure wave function, representative of a precondition frequency, a precondition amplitude and a precondition pressure of the fluid flow in the system, establishing an operating pressure wave function, representative of an operating frequency, an operating amplitude and an operating pressure of the fluid flow desired in the system, determining cycle error between the precondition pressure wave function and the operating pressure wave function, converting the cycle error to flow adjustment, and updating an operating flow with the flow adjustment.

Abstract: A dry powder inhalation system suitable for transpulmonary administration characterized by using a combination of: (1) A vessel housing a freeze-dried composition that contains a single dose of an active ingredient, and has: (i) a non-powder cake-like form, (ii) a disintegration index of 0.015 or more, and (iii) a property of becoming fine particles having a mean particle diameter of 10 microns or less or a fine particle fraction of 10% or more upon receipt of an air impact having an air speed of at least 1 m/sec and an air flow rate of at least 17 ml/sec; and (2) A device capable of applying said air impact to the freeze-dried composition in said vessel and for discharging the powder-form freeze-dried composition that has been made into fine particles.

Abstract: A dry inhaler system includes a vibrating mechanism. A supply of a dry powder is operatively coupled to the vibrating mechanism. A power source communicates with the vibrating mechanism. A sensor communicates with the vibrating mechanism. A feedback control communicates with the sensor and the power source. The feedback control controls power delivered to the vibrating mechanism relative to information provided by the sensor about the performance of the vibrating mechanism.

Abstract: A flow regulation vent includes a fixed portion adapted to engage a gas supply conduit and a spring force biased movable portion connected by a hinge to the fixed portion and flowingly connected to the pressurized gas supply. The fixed portion includes a gas flow orifice. The movable portion is pivotally movable between 1) a relaxed position, whereby at a specified minimum operating pressure, the movable portion is pivoted by the spring force away from the fixed portion to a position to establish a first gas washout flow area between the movable portion and the gas flow orifice; and 2) a fully pressurized position, whereby at a specified maximum operating pressure, the pressurized gas offsets the spring force to pivot the movable portion to a position adjacent the fixed portion to establish a minimum gas washout flow area between the movable portion and the gas flow orifice.

Abstract: A method and apparatus for providing an average signal characteristic profile derived from signals obtained from different cycles of a cyclically recurring physiological phenomenon. A signal produced from first and second cycles of the physiological phenomenon is sampled at a series of data points to obtain second physiological property values at the data points. The change in the second physiological property values for the first cycle signal between a pair of successive data points and the change in the second physiological property values for the second cycle signal between the same pair of successive data points are determined and averaged. The average change amount is applied to a value of the average signal characteristic profile at one of the pair of successive data points to produce a new second physiological property value for the average signal characteristic profile at the other of the data points of the pair.

Abstract: The invention provides a method for obtaining and evaluating spirographic and gas exchange data, involving measuring a concentration of a breathing gas gc(Vx) for a plurality of volumes Vx of breathing gas mix, wherein the measuring is performed on inhaled breathing gas mix, further involving determining an apparatus dead space ApDS, of breathing gas mix in the apparatus not taking part in gas exchange, by evaluating the measured concentrations gc(Vx) as a function of the volume V of the inhaled breathing gas mix. The use of inhaled breathing gas mix allows to determine the apparatus dead space, which is an important parameter when evaluating ventilation efficiency and the like. Furthermore, the invention provides a method in which inhalation and exhalation parts of a spirogram are synchronized, by matching features thereof, in order to further improve the accuracy of gas exchange volumes and derived data.

Abstract: A safety system and method of an air distribution system of a tunnel structure is disclosed. In one embodiment, the air distribution includes a supply unit installed on a particular wall of the first set of walls to facilitate delivery of breathable air from a source of compressed air to an emergency support system of the tunnel structure, a fill site interior to the tunnel structure to provide the breathable air to a breathable air apparatus at multiple locations of the tunnel structure, a secure chamber of the fill site as a safety shield that confines a possible rupture of an over-pressurized breathable air apparatus within the secure chamber, a distribution structure that is compatible with use with compressed air that facilitates dissemination of the breathable air of the source of compressed air to multiple locations of the tunnel structure.

Abstract: A pulse oxygen system and methods for providing oxygen to a user are disclosed. An oxygen mask coupled to a metering valve is provided to a user. An oxygen prescription delivery amount is determined based on and as a function of a real-time operation condition. A metering valve timing is calculated based on the oxygen prescription delivery amount to obtain a pulse delivery time. A pressure and time regulated flow of the oxygen prescription delivery amount of pulsed oxygen is then dispensed to the oxygen mask for a duration of the pulse delivery time in response to detecting the user breathing through the oxygen mask.

Abstract: In one embodiment, the invention provides a medical method for treating a person and comprises repeatedly compressing the person's chest. While repeatedly compressing the person's chest, the method further includes repeatedly delivering a positive pressure breath to the person and extracting respiratory gases from the person's airway using a vacuum following the positive pressure breath to create an intrathoracic vacuum to lower pressures in the thorax and to enhance blood flow back to the heart.

Abstract: This invention relates to a method for controlling a bi-level apparatus. The method includes repeatedly measuring an airflow, choosing an expiration threshold value and choosing an inspiration threshold value. Switching to an inspiration mode takes place if the airflow is greater than the expiration threshold value in a comparison with the expiration threshold value. A switching back to the expiration mode takes place if the airflow is smaller than the inspiration threshold value in a comparison with the inspiration threshold value. Moreover, the invention relates to a bi-level apparatus for performing the method.

Abstract: A substance delivery apparatus for use with a system for supplying breathable gas to a human or animal includes a sensor to measure the pressure of the supplied breathable gas and to detect inhalation by the human or animal; and a reservoir, a conduit, a pump, and a diaphragm to deliver the substance to the human or animal during inhalation at a pressure higher than the supplied pressure of the breathable gas.

Abstract: The delivery of a medicament to a mechanically ventilated patient may include the steps of delivering a respiratory maneuver to such a patient, monitoring the physiological effects of the respiratory maneuver on such patient, automatically establishing an adjustment to the respiratory maneuver in response to the monitored physiological effects, and delivering the adjusted respiratory maneuver to such a patient.

Abstract: A pneumatic single-lumen medical gas conserver combines the advantages of typical single-lumen and dual-lumen conservers. In particular, a pneumatic single-lumen conserver can provide a rapid response to patient inhalations without the need for a more expensive dual-lumen cannula hose. In addition, after delivering oxygen the conserver has a specific pneumatically-implemented delay period before being able to detect the next inhalation to inhibit “double pulse” deliveries. In addition to a conserving or pulse flow mode, the conserver can provide a user-selectable gas flow at a continuous or constant flow mode.

Abstract: A respiratory therapy system includes a driver unit and a patient interface device. The driver unit is adapted to deliver pressurized gas flow from a source to the patient interface device. At least one electronic valve can be used to deliver a desired flow to the patient interface device.

Abstract: A method of treating a patient with a pulmonary disease, where the method includes delivering a dose of aerosolized medicament intermittently to a ventilator circuit coupled to the respiratory system of the patient. Also, a method of treating a patient with a pulmonary disease, where the method includes taking the patient off a ventilator, and administering to the patient, a nebulized aerosol comprising from about 100 ?g to about 500 mg of a medicament. Also a method of treating a patient with a pulmonary disease, the method comprising administering an aerosolized first medicament comprising amikacin to the patient and administering, systemically a second medicament comprising an antibiotic to the patient that also treats the pulmonary disease, wherein a resulting amikacin concentration in the lung and/or pulmonary system is therapeutically-effective, and an amount of the systemically administered antibiotics is reduced.

Abstract: Systems and methods for detecting and treating an obstructive sleep apnea event are disclosed herein. The systems and methods may use an electrical output generating ionic polymer metal composite sensor attached to a region in an airway passage in an oral cavity. The electrical output may be wirelessly transmitted as a signal for indication of an obstructive sleep apnea event. The signal may be further analyzed by a positive airway pressure system for treatment of the obstructive sleep apnea event.

Abstract: A nasal interface device delivers a high flow rate of a gas having a pressure that is adjustable to a patient. The device includes a nasal insert that is adapted to deliver pressurized gas to a nasal cavity of the patient, and receive and direct expired air. The nasal insert has a pressurized breathing gas delivery port and an expired gas port. An expiratory limb pressure regulator is in fluid communication with the expired gas port.

Abstract: Described are a system and a method for monitoring breathing of a patient. The system may include a sensor measuring data corresponding to the patient's breathing patterns and a processing arrangement determining whether the breathing patterns are indicative of a troubled wakefulness state.

Abstract: A self-contained breathing apparatus (SCBA) comprising: a mouthpiece; a breathing component; and a safety quick disconnect comprising: a valve body; a valve spool comprising an L-shaped channel formed such that when the valve spool is appropriately rotated, the L-shaped channel (i) places an opening of the valve body in communication with a first port, or (ii) places the opening in communication with a second port; and a lock mechanism for (i) preventing the valve spool from rotating unless the breathing component is positioned in one of first and second mounts formed on the valve body adjacent the first and second ports, and a replacement breathing component is positioned in the other of the first and second mounts, and (ii) preventing the removal of a breathing component from a mount adjacent to a port which is in communication with the opening.

Abstract: A pressure reducing valve for use in a system adapted to deliver a breathing gas to a patient. The pressure reducing valve is structured to communicate a flow of breathing gas to such a patient's airway during an inspiratory phase. The pressure reducing valve is structured to isolate the flow of breathing gas from the patient's airway and to “dump” the flow of breathing gas and a flow of exhalation gas to atmosphere during the expiratory phase. The flow of breathing gas is dumped to atmosphere through a first number of ports; whereas a flow of exhalation gas is dumped to atmosphere through a second number of ports. Because the flow of breathing gas remains isolated from the flow of exhalation gas, less effort is required by a patient during the expiratory phase.

Abstract: A system and method for displaying a pharmacokinetics/pharmacodynamics drug model for a patient is provided. A monitor is arranged to detect a quantity of anesthetic agent provided to a patient by an anesthesia machine. A display is provided for displaying real-time pharmacokinetics data associated with the quantity of anesthetic agent provided to the patient. Safety control means are provided to initiate the display of real-time pharmacokinetics data for the anesthetic agent only when a predetermined threshold value for the anesthetic agent is detected by the monitor. Alternately, control means are adapted to terminate display of real-time pharmacokinetics data for the anesthetic agent when a predetermined threshold value for the anesthetic agent is detected by the monitor.

Abstract: A self-contained breathing apparatus or a respirator can be equipped with a sensor of ambient airborne conditions. A display unit can be carried by a face mask for the apparatus or respirator. Responsive to output signals from the sensor, the display unit can present an air quality indicator, or a breathability indicator to a user of the apparatus or respirator.

Abstract: A method of providing ventilatory support or treatment of sleep disordered breathing, implemented using an electrically operated and computer controlled fan or blower, a gas delivery tube, and an atmospherically vented face mask or nasal prongs. The method, over a single respiratory cycle, includes cycling administered pressure between and including an upper pressure and a lower pressure to a user's airway. The lower pressure is greater than atmospheric pressure and is maintained only for as long as is required to allow the immediately prior administered gas volume to be at least substantially expelled from the user's respiratory system by its elastic recoil. The lower pressure is immediately thereafter returned to the upper pressure.

Abstract: A pneumatic single-lumen medical gas conserver combines the advantages of typical single-lumen and dual-lumen conservers. In particular, a pneumatic single-lumen conserver can provide a rapid response to patient inhalations without the need for a more expensive dual-lumen cannula hose. In addition, after delivering oxygen the conserver has a specific pneumatically-implemented delay period before being able to detect the next inhalation to inhibit “double pulse” deliveries. In addition to a conserving or pulse flow mode, the conserver can provide a user-selectable gas flow at a continuous or constant flow mode.

Abstract: Double acting respiratory pump apparatus including a pump member reciprocable with respect to two pump chambers to deliver air to a patient via a respirator exhalation system, which also facilitates exhalation of the patient. The exhalation system has a pump unit that is operatively connected to an exhalation valve member and configured for selectively generating an air pressure sufficient for pressurizing one side of the valve member for closing the same when said exhalation system is operating in inhalation mode, and may be operated for opening to allow the patient to exhale therethrough.

Abstract: A diaphragm for a lung demand valve, including a chemical, biological, radiological and/or nuclear (CBRN) layer which is sufficiently resistant to the permeation of at least some CBRN agents and a resilient layer which is resiliently deformable. The CRBN layer is arranged to restrict the permeation of at least some CBRN agents through the diaphragm, and the resilient layer is arranged to allow the diaphragm to be resiliently deformed.

Abstract: The ventilation interface for sleep apnea therapy interfaces a ventilation device to the patient's airways. The ventilation interface includes a pair of nasal inserts made from flexible, resilient silicone which are oval shaped in cross-section and slightly tapered from a base proximal the ventilation supply to the distal tip end. A bead flange is disposed about the exterior of each insert at the distal end of the insert. A bleed port for release of exhaled air is defined through a conical vent projecting normally to the path of the incoming air flow, and continues through a nipple extending to the exterior of the air conduit. In one embodiment, a pair of nasal inserts are integral with a nasal cannula body, with bleed ports axially aligned with each insert. In another embodiment, each insert is independently connected to a separate, thin-walled, flexible supply line.

Abstract: A pneumatic oxygen conserving device for supplying oxygen to a user via a single-tube cannula is described. Inhalation is sensed by negative pressure in an output line 11 which causes a sensing valve 21 to open, thus venting a main control volume 14 via vent line 22. This fall in pressure causes a main control valve 2 to open to supply a pulse of gas. This pressurizes the output line 11 which in turn causes the sensing valve 21 to close, thus preventing further venting. Volume 14 now re-pressurizes via line 15 and restrictor 16 and eventually reaches a level at which valve 2 closes and terminates the pulse of gas supplied to the user. A sensing delay valve 35 is incorporated in the vent line 22 from volume 14 to prevent the volume from venting after the first pulse has been delivered, until after the user has finished inhaling.

Abstract: A closed circuit rebreather including a breathing hose assembly, head assembly and internal counterlung assembly having axial and radial gas flow passageways therethrough, wherein the assembly is housed within a tank and includes a scrubber substantially enclosed along its longitudinal length within a water impervious counterlung bladder, the scrubber including foraminous inner and outer tubes having a carbon dioxide absorbent material filling the space therebetween.

Abstract: The invention concerns a combination control for use in nasal cannula therapy, and includes a high flow, nasal cannula respiratory assistance ducted system, and a pressure relief valve having indicator structure, which typically includes a tubular body, a carrier slidable in the body, a plunger-indicator carried by the carrier, and a spring resisting carrier movement toward a cap on the body that defines an indicator window.

Abstract: Systems and methods for adjusting a desired pressure in a positive airway pressure (PAP) device are provided. In one embodiment, the method includes: a) providing breathing gas under positive pressure to a patient via a PAP device based on current desired pressure, b) monitoring a characteristic of the breathing gas, patient, or PAP device indicative of respiration, c) creating a breathing cycle signal having a first level associated with inhalation and a second level associated with exhalation, the signal being based on the monitored respiration characteristic, d) performing an abnormal breathing check based on the monitored respiration characteristic and the breathing cycle signal, and e) if abnormal breathing is detected, increasing the current desired pressure until a maximum desired pressure is reached, otherwise, decreasing the current desired pressure until a minimum desired pressure is reached. Several embodiments of an apparatus associated with the method are also provided.

Abstract: The invention relates to a breathing apparatus for providing a respiratory gas to a crewmember in a cabin of an aircraft, said breathable apparatus comprising an air inlet (5) for admission of ambient air in said breathing apparatus, an additional gas inlet (2) for admission of additional gas in said breathing apparatus, an outlet nozzle (4) for feeding said crew member with the respiratory gas comprising said ambient air and/or additional gas, said breathing apparatus further comprising neutralizing means (70, 141) for neutralizing at least partially the admission of said additional gas below a predefined cabin altitude (Z1).

Abstract: A breathing system with a facepiece that includes a first port adapted to be placed in fluid connection with the outlet of a regulator assembly to introduce pressurized breathing gas into the facepiece; a second port adapted to be connected to an air purifying system; and an exhaust valve through which the user's exhausted breath can exit the facepiece. The breathing system also includes a pressure adjustment mechanism that includes a communication link in communicative connection with an actuator such that the exhaust pressure adjustment mechanism sets the internal facepiece pressure required to open the exhaust valve, independently of the respiration of the user, to a first pressure when the actuator is in the first state, to a second pressure when the actuator is in the second state. The first pressure is higher than the second pressure.

Abstract: A gas therapy system involves sensing the blood gas concentration of the patient and adapting a gas therapy based on the sensed gas concentration. Disordered breathing may be detected bases on blood gas concentration, and gas or cardiac electrical therapy may be adapted to treat the detected disordered breathing. One or more of sensing the blood gas concentration, detecting disordered breathing, or adapting the therapy may be performed at least in part implantably. The gas therapy is delivered to the patient through an external respiratory device, such as a positive airway pressure device.

Abstract: A breathing assistance device having: a turbine for generating flow of pressurized respiratory gas, a duct for carrying pressurized gas to a patient, a mechanism to control gas pressure capable of elaborating a pressure setting for the turbine, the turbine is connected to a speed sensor for acquiring a signal corresponding to the rotation speed of a rotating element of the turbine, and the mechanism of controlling the calculation linked to the speed sensor in order to elaborate using the signal, a pressure setting sending the pressure setting to the turbine. Another aspect of the invention relates to a method for regulating the pressure of a respiratory gas delivered by a turbine to a patient, the method involving elaborating a pressure setting for the turbine, characterized in that the pressure setting is elaborated using a signal representative of the rotation speed of a rotating element of the turbine.

Abstract: Regulator for underwater breathing apparatus, comprising a box-like body in which is formed a chamber having a first tubular element for connection to a mouthpiece, a second tubular element provided with a regulating valve for supplying air to the inside of the regulator chamber, a conduit for discharging expired air and any residual water, and an aperture on which is positioned a flexible diaphragm surmounted by a cover provided with a set of holes or apertures adapted to allow water to come into contact with the outer surface of the flexible diaphragm; the flexible diaphragm interacts by suitable means with the regulating valve; the diaphragm and the cover lie on, or are parallel to, a plane (M?) facing upwards and inclined forwards relative to a generally upright position of the diver; a plurality of water inlet apertures is formed behind the cover.

Abstract: An apparatus (1) for non-invasive mechanical ventilation comprises a fan (2) of Bi-level type, or BiPAP, for generating an air flow according to a succession of inspiration steps, or IPAP, and exhalation steps, or EPAP. The flow is conveyed in the aerial ducts of a patient (25) by means of a flexible tube (3) connected to a nasal mask (4). A flexible air reservoir (5) is provided pneumatically connected to the duct (3) and the nasal mask (4) in order to subtract from the inspiration flow a certain air amount before that it reaches the patient (25) at the beginning of an IPAP step. During the exhalation EPAP step, since the air flow pressure decreases automatically, there is the emptying at least partial of the flexible air reservoir (5), whereas the air exhaled by the patient exits through an opening (14) made on the nasal mask (4).

Abstract: A scuba mask purging apparatus and method providing selective introduction of pressurized air into a scuba mask to initiate purging, pressure balancing, and de-fogging. An inlet valve, typically positioned conveniently on the top or the side of the mask may control the release of pressurized air into the mask. A pressure-sensitive outlet valve releases the pressurized air to force water from the mask. The outlet valve may be positioned on the lower portion of the mask or at a location where water is likely to collect.

Abstract: Fluid regulators provide a fluid to a cannula for use by a person. Fluid conservers also a fluid to a cannula for use by a person. A fluid conserver may be operational in a continuous flow mode of operation and an intermittent flow mode of operation. The selection of either the continuous flow mode of operation and the intermittent flow mode of operation may be based on a position of a flow selector. A home fill device may operate with a fluid conserver and may include an oxygen concentrator which provides a source of fluid.