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

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.

Abstract: This disclosure describes systems and methods for compensating for leakage when determining the respiratory mechanics of a patient during delivery of gas from a medical ventilator to a patient. The systems and methods include monitoring an instantaneous flow in the ventilation system based on one or more measurements of pressure and flow in ventilation system. The leakage is modeled using a predetermined leakage model. A leak-compensated instantaneous lung flow of gas inhaled or exhaled by the patient is estimated. Using the leak-compensated lung flow and a predetermined respiratory mechanics model, the respiratory mechanics of a patient may be estimated including at least one of a leak-compensated lung compliance and a leak-compensated lung resistance. The method may include using a dynamic respiratory mechanics model or a static respiratory mechanics model that requires use of a pause maneuver to collect the necessary data.

Abstract: This disclosure describes systems and methods for detecting disconnect conditions in a ventilator. The disclosure describes a model-based enhancement to conventional disconnect detection. The methods and systems described herein compensate for the additional leakage that occurs due to inelastic and elastic leaks in the ventilation system. One method described includes calculating the actual leakage from the ventilation system including leaks from elastic leakage and inelastic leakage based on measurements of pressure and flow in the ventilation system for a breath and then comparing this leakage to a calculated hypothetical maximum allowable leakage determined based on an operator-selected maximum allowable leakage and the measurements of pressure for the same breath. Disconnection is assumed if the actual leakage is greater than the maximum allowable leakage.

Abstract: This disclosure describes systems and methods for purging narrow diameter sensor tubing, occasionally referred to as “sensor lines”, in a ventilation system. The disclosure describes a novel approach in which a series of short, periodic releases of pressurized gas through the sensor tubes are used to clear any blockages due to condensation or patient secretions.

Abstract: This disclosure describes systems and methods for compensating for inelastic and elastic leaks in a ventilation system. The disclosure describes a model-based enhancement to conventional pressure triggering methodology that optimizes the timing and patient work of pressure triggering performance. The methods and systems described herein compensate for the additional effort a patient has to exert to generate the same amount of airway pressure drops compared to no leak condition. One method described includes calculating an elastic leakage and an inelastic leakage based on current measurements of pressure and flow in the ventilation system and then compensating a pressure threshold for the effects of the inelastic and elastic leaks in the system.

Abstract: This disclosure describes systems and methods for compensating for inelastic and elastic leaks in a ventilation system. The disclosure describes a model-based enhancement to conventional flow triggering and cycling methodologies that improves the timing and patient work of flow-based triggering and cycling performance. The methods and systems described herein compensate for the leak condition and minimize additional effort a patient has to exert to generate the same patient synchrony and comfort level compared to no leak condition. One method described includes calculating an elastic leakage and an inelastic leakage based on current measurements of pressure and flow in the ventilation system and then estimating a leak-compensated lung flow using the inelastic and elastic leaks and pneumatic attributes of the patient-ventilator system.