Fig. 1

Medium pressure reservoir (MPR) to bridge gaps in oxygen delivery. a Picture of the MPR. b Functional states of the MPR. Drain state represents the power outage scenario where oxygen is drawn from the oxygen reservoir to patients. Fill state represents the normal operating condition (power available) where input from the oxygen concentrator is used to fill the reservoir and/or directed to patients. Bypass state is used when filling the reservoir is not a priority (reservoir is full or patient demand is high). In this state, oxygen is drawn directly from the oxygen concentrator to patient