Methods and systems for compensation of tubing related loss effects

A ventilator system comprising:

• a pressure generating system adapted to generate a volume of breathing gas;
• a ventilation tubing system including a patient interface for connecting the pressure generating system to a patient;
• at least one sensor operatively coupled to at least one of the pressure generating system and the ventilation tubing system;
• a loss effect compensation module, the loss effect compensation module configured to provide at least one instruction to consecutively deliver a plurality of substantially equal volume amounts into a closed ventilator circuit during a ventilator self-test, receive a pressure measurement for each volume delivery, calculate a change in pressure for each volume delivery, consecutively release a plurality of substantially equal volume amounts from the closed ventilator circuit during the ventilator self-test, calculate a change in pressure for each volume release, fit the calculated change in pressure data for volume delivery and volume release to an inhalation non-linear tubing compliance model equation and an exhalation non-linear tubing compliance model equation, respectively, derive one or more inhalation tubing compliance compensation coefficients from the inhalation non-linear model equation, and derive one or more exhalation tubing compliance compensation coefficients from the exhalation non-linear model equation;
• and
• a processor in communication with the pressure generating system, the at least one sensor, and the loss effect compensation module and configured to receive the at least one instruction to consecutively deliver a plurality of substantially equal volume amounts from the loss effect compensation module.

A computer-readable medium having computer-executable instructions for performing a method of ventilating a patient with a ventilator, the method comprising:

• consecutively delivering a plurality of substantially equal volume amounts into a closed ventilator circuit during a ventilator self-test;
• receiving a pressure measurement for each volume delivery;
• calculating a change in pressure for each volume delivery;
• consecutively releasing a plurality of substantially equal volume amounts from the closed ventilator circuit during the ventilator self-test;
• calculating a change in pressure for each volume release;
• fitting the calculated change in pressure data for volume delivery and volume release to an inhalation non-linear compliance model equation and an exhalation non-linear compliance model equation, respectively;
• deriving one or more inhalation tubing compliance compensation coefficients from the inhalation non-linear model equation;
• and
• deriving one or more exhalation tubing compliance compensation coefficients from the exhalation non-linear model equation.