| abstract |
A method of predicting critical points in patient respiration includes monitoring at least one characteristic of a respiratory effort waveform of a patient to detect a respiratory event. A refractory period is defined that includes a hard refractory period during which time the respiratory event cannot be responded to and a soft refractory period following the hard refractory period. The respiratory event outside of the refractory period is detected as a function of a first set of predetermined parameters for the monitored at least one characteristic and the respiratory event within the soft refractory period is detected as a function of a second set of predetermined parameters for the monitored at least one characteristic. The respiratory event may be inspiration onset and the characteristic of the respiratory effort waveform monitored is at least one of slope and amplitude. The refractory period may be defined based on detection of inspiration offset and further may be defined based on inspiration offset, an average respiratory period, and an average time of inspiration. Further, stimulation may be provided in response to a detected inspiration onset. Another method of predicting critical points includes sampling the amplitude of the respiratory effort waveform of a patient. A sample signal is generated representative of at least one characteristic of the respiratory effort waveform based on each amplitude sample. The sample signals representative of the at least one characteristic of the respiratory effort waveform are monitored and a respiratory event is detected as a function of at least two sample signals. Apparatus and systems for use with such methods are also described. |