Method for determining respiratory timing parameters from respiratory monitoring measurements of a subject

A computer program comprising instructions which, when executed by a computing device, cause the computing device to carry out a method for generating respiratory timing parameters from respiratory monitoring measurements of a subject, the method comprising the steps of:

• receiving a respiratory effort signal of a subject from at least one respiratory effort measurement sensor and a respiratory flow signal of the subject from at least one respiratory flow measurement sensor;
• processing the respiratory effort signal to identify an ensemble of peaks and an ensemble of valleys in the respiratory effort signal;
• identifying times associated with the valleys in the respiratory effort signal as preliminary inspiratory onset times;
• segmenting the respiratory effort signal into peak-to-peak time intervals based on the identified peaks and valleys;
• and
• refining the preliminary inspiratory onset times within respective peak-to-peak time intervals of the respiratory effort signal by:
• calculating a first derivative of the respiratory flow signal in a respective peak-to-peak interval,
• identifying local peaks and valleys in the respiratory flow signal first derivative, calculating a time midpoint between the time of a local valley in the respiratory flow signal first derivative closest in time to the later endpoint in the respective peak-to-peak time interval and the time of a local peak in the respiratory flow signal first derivative in the respective peak-to-peak time interval, and
• determining whether the respiratory effort signal at the calculated time midpoint satisfies a predetermined inspiratory onset time condition, and if satisfied, selecting the calculated time midpoint as an inspiratory onset time instead of the preliminary inspiratory onset time for that peak-to-peak interval, whereas if the condition is not satisfied, keeping the preliminary inspiratory onset time as the inspiratory onset time for that peak-to-peak interval.