1995 OPEN FORUM Abstracts
Oxygen Pulsing Devices: Effects Of Different Flow Profiles On Simulated Rest And Exercise Conditions
Alex Adams RRT, Bob McCoy RRT, Peter Bliss BSME. St. Paul Ramsey Medical Center, St. Paul, MN.
It is well known that oxygen pulsing devices conserve oxygen use with a savings range of 2:1 to 7:1 depending, in part, on the pulse flow profiles of the device. Less well known is the effect of flow profile on their ability to respond to increased demand such as an increased respiratory rate.
Methods: Using a Rosemount 2024 differential pressure transmitter and a National Instruments Lab PC data acquisition system we measured, precisely, the flow profiles of 3 commonly used pulsing devices at an equivalent of 4 LPM setting (figure) and extrapolated their performance to an increased respiratory rate, a simulated exercise (SE) condition.
SEE ORIGINAL GRAPH
Results: At, supposedly, the equivalent setting each device delivered an FIO2 different from each other and from the equivalent constant flow (CF) setting: 0.34, 0.26, 0.24, and 0.32 for devices A, B, C, and CF, respectively. Extrapolation to the SE condition, CF FIO2 fell to 0.26, device A decreased to 0.29 while devices B, C delivered a constant FIO2.
Conclusions: Demand oxygen pulse devices perform differently at rest and respond to SE by retaining FIO2 better than CF oxygen. Each pulsing device should be prescribed and administered to meet oxygen saturation goals for rest and exercise.