Abstract: The present invention relates to an integrated sleep diagnosis and treatment device, and more particularly to an integrated apnea diagnosis and treatment device. The present invention additionally relates to methods of sleep diagnosis and treatment. The sleep disorder treatment system of the present invention can use a diagnosis device to perform various forms of analysis to determine or diagnose a subject's sleeping disorder or symptoms of a subject's sleep disorder, and using this analysis or diagnosis can with or in some embodiments without human intervention treat the subject either physically or chemically to improve the sleeping disorder or the symptoms of the sleeping disorder. The diagnostic part of the system can use many different types of sensors and methods for diagnosing the severity of the symptoms of or the sleep disorder itself. The treatment part of the system can use a device to physically or chemically treat the subject's symptoms or sleep disorder itself.

Abstract: Described is a system including a sensor and a processing arrangement. The sensor measures data corresponding to a patient's breathing patterns. The processing arrangement analyzes the breathing patterns to determine whether the breathing patterns are indicative of a REM sleep state. In another embodiment, the processing arrangement analyzes the breathing patterns to determine whether the breathing patterns are indicative of one of the following states: (i) a wake state and (ii) a sleep state. In another embodiment, a neural network analyzes the data to determine whether the breathing patterns are indicative of one of the following states: (i) a REM sleep state, (ii) a wake state and (iii) a sleep state. In another embodiment, the processing arrangement analyzes the data to determine whether the breathing pattern is indicative of an arousal.

Abstract: CPAP treatment apparatus is disclosed having a controllable flow generator (34, 38, 40) operable to produce breathable gas at a treatment pressure elevated above atmosphere to a patient by a delivery tube (32) coupled to a mask (30) having connection with a patient's airway. A sensor (44, 50, 56, 58) generates a signal representative of patient respiratory flow, that is provided to a controller (54, 62, 64). The controller (54, 62, 64) is operable to determine the occurrence of an apnea from a reduction in respiratory airflow below a threshold, and if an apnea has occurred, to determine the duration of the apnea and to cause the flow generator (34, 38) to increase the treatment pressure. In one preferred form the increase in pressure is zero if the treatment pressure before the apnea exceeds a pressure threshold.

Abstract: This disclosure describes systems and methods for providing adaptive base flow scheduling during ventilation of a patient to optimize patient-machine synchrony and accuracy of estimated exhaled as well as inhaled tidal volumes. Further, this disclosure describes systems and methods for providing adaptive inspiratory trigger threshold scheduling during the adaptive base flow scheduling. Further still, this disclosure describes systems and methods for determining an estimated leak flow and adjusting the adaptive base flow scheduling and the adaptive inspiratory trigger threshold scheduling based on the estimated leak flow. Moreover, this disclosure describes systems and methods for determining a change in the estimated leak flow and adjusting the adaptive base flow scheduling and the adaptive inspiratory trigger threshold scheduling based on the change in the estimated leak flow.

Abstract: Methods and/or apparatuses for treating sleep-disordered breathing (SDB) are provided. In particular, systems and/or methods are provided which may temporarily boost the pressure of a supply of breathable gas provided by an AutoSet device for the treatment of hypopnea. In certain example embodiments, a supply of breathable is provided to patients to treat apneas and/or hypopneas. The presence and/or absence of apneas and/or hypopneas are detected (e.g. by monitoring the Apnea-Hypopnea Index). When hypopnea events are detected, the pressure of the supply of breathable gas temporarily is increased above the Pcrit and/or CPAP levels, at least during patient inspiration. When the hypopnea events are normalized, the pressure is reduced. In certain example embodiments, the pressure will not be increased when a non-hypopnea event is detected at the same time as a hypopnea event.

Abstract: Described is a system including a sensor and a processing arrangement. The sensor measures data corresponding to a patient's breathing patterns. The processing arrangement analyzes the breathing patterns to determine whether the breathing patterns are indicative of a REM sleep state. In another embodiment, the processing arrangement analyzes the breathing patterns to determine whether the breathing patterns are indicative of one of the following states: (i) a wake state and (ii) a sleep state. In another embodiment, a neural network analyzes the data to determine whether the breathing patterns are indicative of one of the following states: (i) a REM sleep state, (ii) a wake state and (iii) a sleep state. In another embodiment, the processing arrangement analyzes the data to determine whether the breathing pattern is indicative of an arousal.

Abstract: A controller or processor(s) (1112) implements detection of respiratory related conditions, such as asynchrony, associated with use of a respiratory treatment apparatus (1102) or ventilator. Based on data derived from sensor signals associated with the respiratory treatment, the detector may evaluate a feature set of detection values to determine whether or not an asynchrony occurs in a breath of the patient's respiratory cycle such as by comparing the values against a set of thresholds. Different events may also be identified based on the particular feature set and threshold(s) involved in the detection processing. Automated determination of feature sets may also be implemented to design different asynchrony event classifiers. The methodologies may be implemented by computers or by respiratory treatment apparatus.

Abstract: A process and system are provided for transmitting monitoring states between respirators. The process includes the detection of and recording of monitoring states of a monitoring unit (5) of at least a first monitoring period (10) of a first respirator (2). There is an assignment of an identification to the monitoring states of the monitoring unit (5) of the at least first monitoring period (10) of the first respirator (2). There is a transmission of the monitoring states of the monitoring unit (5) of the at least first monitoring period (10) of the first respirator (2) to a second respirator (3). This is followed by a setting of the monitoring unit (5) of the second respirator (3) corresponding to the transmitted monitoring states of the monitoring unit (5) of the at least first monitoring period (10) of the first respirator (2). This is then followed by a repetition of steps for the monitoring states of the monitoring unit (5) of each additional monitoring period (10) of the first respirator (2).

Abstract: A ventilator with a safe standby mode is provided. The safe standby mode allows a user to disconnect a patient from the ventilator, without the ventilator generating alarms and while maintaining previously entered ventilation parameters. In addition, while in the safe standby mode, a patient connection status is monitored, and a ventilation mode is entered automatically if the ventilator determines that a patient is connected to the ventilator while the ventilator is in the safe standby mode.

Abstract: This disclosure describes systems and methods for providing novel adaptive base flow scheduling during ventilation of a patient to optimize the accuracy of estimated exhaled tidal volume. Further, this disclosure describes systems and methods for providing novel adaptive inspiratory trigger threshold scheduling during the novel adaptive base flow scheduling.

Abstract: A positive airway pressure apparatus is automatically adjusting. Pressure increases in response to apnea events when the apparatus is in one or more responsive states. Pressure does not increase in response to apnea events when the apparatus is in a non-responsive state. The apparatus switches between responsive and nonresponsive states depending upon any of a number of different criteria that help differentiate between open airway apnea events and closed airway apnea events.

Abstract: This invention relates to a measuring head which comprises an intake, an outlet, a mouthpiece and an electrically controlled proportional valve. The intake may be connected to a pressurized gas reservoir. The outlet releases exhaled gas and excess gas into the ambient. A mouthpiece provides gas to a subject and accepts exhaled gas from the subject. The electrically controlled, proportional valve is pneumatically connected between said intake and said mouthpiece for controlling the gas flow from said intake to said mouthpiece and said outlet. The invention further relates to a method for controlling a gas flow from the intake to the outlet.

Abstract: A system and method for displaying the status of a patient on ventilation is disclosed including a ventilator system configured to provide mechanical ventilation to a patient and a display device operatively associated with the ventilator system. The display device is configured to display a user interface including a pictogram having patient status information related to the ventilator system. The pictogram includes a central section configured to display patient status information relating to an overall status of the patient and at least one group section configured to display patient status information relating to a particular category of ventilatory status parameters.

Abstract: The function of a respiration system, with a patient port (1) with connected inspiration branch (3) and expiration branch, is checked. A rebreathing line (9) connects the inspiration branch to the expiration branch. A reservoir (25) is connected to a reservoir port (27) in the rebreathing line. An actuatable control valve (29) is provided in the rebreathing line between the expiration branch and the reservoir port. A pressure sensor (33) is connected to the rebreathing line. A control unit (39) is connected to the control valve and to pressure sensor. The process includes closing the control valve for a preset inspiration time and opening it for a preset expiration time. The value sent by the pressure sensor is detected with the control valve opened during the expiration time and compared with a preset first threshold valve. An error message is generated when the value sent exceeds the first threshold value.

Abstract: Embodiments of the present invention provide systems and methods for delivering respiratory treatment to a patient. For example, a treatment system may include a mechanism for delivering a positive pressure breath to a patient, and one or more limb flow control assemblies which modulate gas flow to and from the patient. Exemplary treatment techniques are embodied in anesthesia machines, mechanical ventilators, and manual ventilators.

Abstract: An optimized system for providing medical support to a patient is disclosed. The system has a plurality of modular components that may be assembled to create a connection between a support machine and the patient wherein at least one of the modular components comprises an information tag for the storage of data and at least one of the modular components comprises an information sensor for the reading and transmission of the data. Once read and transmitted by the sensor, the data may be used to optimize the operation of the support machine.

Abstract: A method for managing patient ventilator operation includes receiving data representing one or more hemodynamic parameters. In response to the received data representing the one or more hemodynamic parameters, one or more commands are provided for adaptively altering ventilator operation.

Abstract: Introduced are methods and systems for an adjustable bed device configured to: gather biological signals associated with multiple users, such as heart rate, breathing rate, or temperature; analyze the gathered human biological signals; and heat or cool a bed based on the analysis.

Abstract: An apparatus and method to determine the relative humidity of a fuel cell system. A controller is cooperative with a first device and a second device to receive a valve signal and a high frequency resistance value. The controller controls the relative humidity of a fuel cell stack based on the estimation of the relative humidity of the fuel cell stack based on one or more algorithms. The controller modifies the relative humidity of the fuel cell stack through changes in the position of a valve based on at least one of the valve signal and the high frequency resistance value. In one form, the relative humidity of the fuel cell system is determined without the need of a humidity sensor.

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: An apparatus to generate nitric oxide is disclosed in one embodiment in accordance with the invention as including a heat source and a vessel containing the heat source. A tablet may be placed within the vessel such that it is in thermal communication with the heat source to receive heat therefrom. The tablet may contain reactants that are substantially non-deliquescent and form nitric oxide in response to heat from the heat source.

Abstract: A detection circuit includes an amplifier circuit, a rechargeable unit, a first comparator, a second comparator, a reference voltage providing circuit, a first resistor R1, a second resistor R2, and a processing unit. The amplifier circuit is connected to a bridge circuit sensor and amplifies signals output by the bridge circuit sensor to an output voltage Vo. The reference voltage providing circuit provides a reference voltage Vref1. A charge current of the rechargeable unit is (Vref1?V0)/(R1+R2), and a discharge current is (Vref1?VCC)/R1. The processing unit controls the rechargeable unit to be charged for a time period T1 and to be discharged during a time period T2. The processing unit then calculates the output voltage Vo according to an equation: (Vref1?V0)×T1/(R1+R2)=(Vref1?VCC)×T2/R1, and obtains the signals according to the output voltage Vo.

Abstract: This disclosure describes systems and methods for monitoring and evaluating ventilatory data to provide useful notifications and/or recommendations. Indeed, many clinicians may not easily identify or recognize data patterns and correlations indicative of certain patient conditions or the effectiveness of ventilatory treatment. Further, clinicians may not readily determine appropriate adjustments that may address certain patient conditions or the effectiveness of ventilatory treatment. Specifically, clinicians may not readily detect or recognize the occurrence of high-delivered VT, during various types of ventilation. According to embodiments, a ventilator may be configured to monitor and evaluate diverse ventilatory parameters to detect an occurrence of and potential causes for high-delivered VT, and may subsequently issue suitable notifications and/or recommendations.

Abstract: A mask assembly includes a mask with an inflatable bladder. The internal pressure of the inflatable bladder can be set to be higher than the delivered therapeutic pressure. The pressure offset may be constant, or it may vary over the range of therapeutic pressures. Thus, the force necessary to maintain a contact seal between the mask and the patient can be reduced, thereby providing a system that is more comfortable to the patient, which increases patient compliance.

Abstract: A patient interface that provides breathable gas to a person has a face engaging cushion that includes an internal cavity. In the internal cavity fluid is located, and a control means that is capable of communicating with the fluid can incite change to a property or to properties of the fluid.

Abstract: The present disclosure pertains to a portable handheld pressure support system configured to deliver a pressurized flow of breathable gas to the airway of a subject. The pressure support system is configured to treat COPD and/or other patients suffering from dyspnea and/or other conditions. The pressure support system is configured to be small and lightweight so that a subject may carry the system and use the system as needed without requiring a device to be worn on the face. The present disclosure contemplates that the portable handheld pressure support system may be used to treat symptoms and/or conditions related to dyspnea, and/or for other uses. In one embodiment, the system comprises one or more of a pressure generator, a subject interface, one or more sensors, one or more processors, a user interface, electronic storage, a portable power source, a housing, a handle, and/or other components.

Abstract: A therapy system configured to wash out or flush out the oral and/or nasal cavity to reduce the effective dead space and reduce the work of breathing. The system may displace the expired air in the oral and/or nasal cavity with atmospheric air, or air with altered concentrations, for example, increased humidity, or oxygen levels. A sealed oral interface is provided to the mouth of a patient to supply a volume of pressurized gas. A control system to synchronize the supply of pressurized gas with the patients respiratory cycle. The supply of respiratory gas may be provided during only a portion of the respiratory cycle.

Abstract: This disclosure describes systems and methods for monitoring and evaluating ventilatory parameters, analyzing those parameters and providing useful notifications and recommendations to clinicians. That is, modern ventilators monitor, evaluate, and graphically represent multiple ventilatory parameters. However, many clinicians may not easily recognize data patterns and correlations indicative of certain patient conditions, changes in patient condition, and/or effectiveness of ventilatory treatment. Further, clinicians may not readily determine appropriate ventilatory adjustments that may address certain patient conditions and/or the effectiveness of ventilatory treatment. Specifically, clinicians may not readily detect or recognize the presence of asynchrony during ventilation.

Abstract: A method for providing battery security in a breathing assistance system configured to provide breathing assistance to a patient is provided. A battery security system of the breathing assistance system receives battery data from a battery received in the breathing assistance system, and analyzes the received battery data to determine whether the battery is approved for use in the breathing assistance system. If the battery is determined to be approved for use in the breathing assistance system, the battery is allowed to provide power to the breathing assistance system. If the battery is not determined to be approved for use in the breathing assistance system, the battery is prevented from providing power to the breathing assistance system.

Abstract: A carbon-dioxide sampling system for accurately monitoring carbon dioxide in exhaled breath. The system includes a ventilator. The ventilator is configured to ventilate a patient with respiratory gases. The ventilator includes a carbon-dioxide sampling control unit and a carbon-dioxide analyzer. The carbon-dioxide sampling control unit is configured to control the timing of sampling of carbon dioxide in the exhaled breath of a patient, and to control the timing of the analysis of exhaled gases by the carbon-dioxide analyzer.

Abstract: This disclosure describes systems and methods for configuring a ventilator to estimate the carinal pressure to minimize the work of breathing due to a breathing tube. A patient's carina is a cartilaginous ridge located at the site of the tracheal bifurcation between the two primary bronchi. An estimated carinal pressure (a pressure estimated to exist at the patient carina) may be determined and used as feedback control for the carinal pressure. According to embodiments, the estimated carinal pressure may be compared to the carinal pressure command to determine an error. The carinal pressure command may be positive end expiratory pressure (PEEP) or some other suitable target pressure. The error between the estimated carinal pressure and the carinal pressure command may then be used as feedback control to achieve the carinal pressure command and thereby to minimize the work of breathing due to the breathing tube.

Abstract: An implanted stimulation device or air control device are activated by an external radar-like sensor for controlling apnea. The radar-like sensor senses the closure of the air flow cavity, and associated control circuitry signals (1) a stimulator to cause muscles to open the air passage way that is closing or closed or (2) an air control device to open the air passage way that is closing or closed.

Abstract: An apparatus for treating sleep disordered breathing may include: a flow generator to deliver a supply of air at positive pressure to a patient; a user interface, the user interface comprising: a display configured to display a plurality of screens; and a set of controls; and a controller in communication with the user interface and configured to control operation of the flow generator, wherein the flow generator is configured to couple with at least one accessory device and during a first mode of operation of the flow generator the controller determines a first screen of the plurality of screens to display on the display based on the at least one accessory device, the first screen of the plurality of screens being configured to enable adjustment of one or more parameters related to the operation of the at least one accessory device or the flow generator using the set of controls.

Abstract: Respiratory pressure treatment apparatus include automated methodologies for controlling modulation of pressure during an inspiratory phase or an expiratory phase of patient respiration. The changes in pressure result in various pressure waveforms that may be suitable for treating patients suffering from respiratory insufficiency such as Chronic Obstructive Pulmonary Disease. In example embodiments, a pressure rise or pressure increase may be controlled during a period of patient expiration by implementation of linear, cubic and/or quartic functions that serve as control parameters in a processor that controls a flow generator. One or more of the functions may optionally serve as a control parameter to control the pressure increase during an expiration period and a following decrease during the period of expiration. In some embodiments, such functions may further control a decrease in pressure during a period of patient inspiration, such as a decrease prior to mid-inspiration.

Abstract: A compressed air control device for a CPAP device comprises a pressure measuring device for measuring a variation of the pressure in a hollow body of the CPAP device and for generating a corresponding pressure signal, a pressure variation evaluating device for evaluating the measured variation of the pressure according to at least one predetermined criterion and for generating a pressure modulation control signal based on the result of the evaluation, and a pressure modulating device for receiving a substantially constant compressed air stream and for outputting a modulated compressed air stream to the CPAP device. The pressure modulating device is configured in such a way that, in response to the pressure modulation control signal, it modulates the pressure of the compressed air stream output to the CPAP device.

Abstract: Methods relating to the power management of positive airway pressure apparatus using a battery are disclosed herein. The methods, in various aspects, are adapted to prolong the delivery of a positive airway pressurized therapy when the positive airway pressure apparatus is operated under battery power.

Abstract: A ventilator is configured to assist a user with breathing, while eliminating the need for extraneous sensors and tubing normally found in prior art ventilators. The ventilator relies on a predetermined relationship between a measurable quantity associated with a compressed gas and the maximum pressure of that compressed gas upon delivery to the user. The measurable quantity may be mass flow rate of the compressed gas or pressure within a delivery lumen used to transport the compressed gas, among others. Based on the predetermined relationship, the control logic within the ventilator determines whether the pressure of compressed gas delivered to the user exceeds a maximum allowable pressure. When the maximum pressure is exceeded, the control logic initiates corrective action to reduce the pressure of the compressed gas.

Abstract: A positive airway pressure (PAP) device for supplying a flow of breathable gas to a patient includes a first housing; a flow generator provided in the first housing, the flow generator configured to generate a flow of breathable gas; a second housing configured to be connected to the first housing, the second housing including a channel having an inlet configured to receive the flow of breathable gas and an outlet configured to discharge the flow of breathable gas, wherein the first housing is provided on top of the second housing such that a footprint of the PAP device is not substantially increased beyond a footprint of the second housing.

Abstract: A respiration system feeds an anesthetic gas having, a density ?gas, with a Y-piece for connection to a patient, with a respiration circuit having an inspiration branch and an expiration branch, which extend away from the Y-piece. A first supply line from a branch in the expiration branch leads to an anesthetic gas discharge valve and a second supply line from the branch leads to a reservoir. A too high pressure, opposing expiration, cannot build up in the expiration branch and losses of anesthetic gas are kept to a minimum. A prestressing device exerts a prestressing force onto the valve body of the anesthetic gas discharge valve against the effect of gravity. The mass mvalve and the prestressing force determine a threshold pressure in the anesthetic gas discharge line that results in an opening of the anesthetic gas discharge valve.

Abstract: Systems and methods for estimating a leak flow in a breathing assistance system including a ventilation device connected to a patient are provided. Data of a flow waveform indicating the flow of gas between the ventilation device and the patient is accessed. A specific portion of the flow waveform is identified, and a linear regression of the identified portion of the flow waveform is performed to determine an estimated leak flow in the breathing assistance system.

Abstract: A positive airway pressure apparatus is automatically adjusting. Pressure increases in response to apnea events when the apparatus is in one or more responsive states. Pressure does not increase in response to apnea events when the apparatus is in a non-responsive state. The apparatus switches between responsive and nonresponsive states depending upon any of a number of different criteria that help differentiate between open airway apnea events and closed airway apnea events.

Abstract: The present invention is a breathing improvement monitor that continuously measures involuntary breathing. The monitor is a sensor apparatus that is attached to a patient's mask which is connected to the monitoring apparatus. The sensor may be reusable and attachable and detachable to a mask or it may be an integral part of a breathing mask. The sensor technology may be any type sufficient in the art, including but not limited to solid state sensors, transducers, electromagnetic microturbines and the like. Since the mask does not have to be removed and the sensor provides constant signal to the monitoring apparatus, a real time status of a patient's involuntary breathing capability may be determined for a doctor's consideration.

Abstract: A respirator has a shell that defines a breathable air zone for a user wearing the respirator. An air flow control system for the respirator has an air delivery conduit within the shell of the respirator, a valve member moveable relative to the air delivery conduit and within the shell to vary the amount of air flow through the air delivery conduit, and a valve actuator outside of the shell of the respirator. The valve actuator is manipulatable by a user of the respirator while wearing the respirator to control movement of the valve member.

Abstract: An airflow control valve (20) for use in a breathing apparatus (10) to control a flow of air from a pressurised air supply to a respirator. The valve comprises an inlet port (31) for connection to a pressurised air supply, and first (32) and second (33) outlets. The valve is configurable between a first position in which the inlet port is in restricted fluid communication with the first outlet to allow a restricted flow of air from the inlet port to the first outlet and in which the second outlet is sealed from the inlet port and, a second position in which the inlet port is in substantially unrestricted fluid communication with the second outlet to allow an unrestricted flow of air from the inlet port to the second outlet.

Abstract: A portable life support apparatus (1102) and particularly a respiratory support apparatus adapted to be easily mounted to a stretcher is disclosed. Prior devices that attach onto a stretcher are heavy and cumbersome and obstruct access to the patient. Accordingly, there is a great need for a portable emergency support device that overcomes the weight, size, positioning, and other portability disadvantages. One aspect relates to a portable life support device including at least one ambient gas inlet (14); a conditioned gas outlet (30); an oxygen concentrator (26,28) fluidly connected between the at least one gas inlet and the gas outlet, and a ventilator (44) fluidly connected downstream from the oxygen concentrator.

Abstract: The present invention provides a gas delivery device and system and methods for delivering humidified pressurized gas through a conduit to a subject. The configuration of the elements of the gas delivery device enable the device to be conveniently oriented from a horizontal to vertical position to suit the needs of a user. The gas delivery device may incorporate a Helmholtz resonator for dampening sound of the motor. The conduit may incorporate concentric tubes to allow it to conveniently engage the humidifier at a single aperture. The invention includes a method of operating a blower motor for a gas delivery device using a single Hall sensor.

Abstract: A CPAP apparatus has a variable rise time (iii) from a base level of positive air pressure during expiration (EPAP) to a higher level during inspiration (IPAP). The rise time is adjusted in order to reduce obstruction, resistance or instability in the upper airway.

Abstract: Automated methods provide hypopnea detection for determining a hypopnea event and/or a severity of a hypopnea event. In some embodiments, a calculated short-term variance of a measured respiratory flow signal are compared to first and second proportions of a calculated long-term variance of the measured flow signal. A detection of the hypopnea may be indicated if the first measure falls below and does not exceed a range of the first and second proportions during a first time period. In some embodiments, a hypopnea severity measure is determined by automated measuring of an area bounded by first and second crossings of a short-term measure of ventilation and a proportion of a long-term measure. The detection methodologies may be implemented for data analysis by a specific purpose computer, a detection device that measures a respiratory airflow or a respiratory treatment apparatus that provides a respiratory treatment regime based on the detected hypopneas.

Abstract: The present disclosure pertains to an airflow shaping system (10) configured to deliver a shaped, pressurized flow of breathable gas to the airway of a subject (12). In some embodiments, the system comprises a pressure generator (14), a subject interface (16), a flow shaper (18), one or more sensors (20), one or more processors (22), electronic storage (24), a user interface (26), and/or other components. Respiratory therapy delivered to a patient's lungs may be enhanced with a shaped flow. A turbulent flow of gas delivered to a patient's lungs is inefficient in the amount of energy required to deliver the gas and because it requires more gas energy to reach the lower airways due to resistance from the airway walls. The system may be used for respiratory therapy applications including pressure support therapy, inexsufflation therapy, airway medication delivery, and/or other applications.

Abstract: This disclosure describes systems and methods for compensating for leakage when during delivery of gas from a medical ventilator in a proportional assist mode to a patient. The technology described herein includes systems and methods to compensate the delivery of PA ventilation for leakage in the patient circuit by using leak-compensated lung flows as well as leak-compensated respiratory mechanics parameters (lung compliance and lung resistance) estimated in a manner that compensates for elastic and inelastic leaks from the ventilation system.