Figure 1.
Representative example of the findings in an individual subject during each trial. The labeling at the top of each column denotes the separate trials; that at the bottom indicates the Naughton stage achieved. The nasal and mouth airflow signals are unidirectional because only inspiration is displayed. In the Device 4 experiment, the polarity was reversed. Note the decreases in percent arterial saturation as measured by pulse oximetry (SpO2) with exertion with each conserver, the fluctuating breathing pattern, and the inconsistent conserver actuations and bolus sizes. Nasal V·e = the minute ventilation with nose breathing in L/min. Mouth V·e = the minute ventilation with mouth breathing in L/min; O2 cylinder flow = the flow rate of O2 from each conserver in L/min.