We describe a solid-state, silicon integrated, bidirectional flow sensor for respiratory applications. The sensor is a thermal vector sensor. The electronic circuitry for obtaining bidirectional sensitivity is presented together with actual application to a healthy volunteer put on mechanical ventilation. The sensor's input flow range is from -60 to +60 L/min, and its rise-time is ≤40 ms and fall-time is ≤60 ms. The effect of changes in gas composition as used in mechanically ventilated patients on the sensor output signal are estimated to be less than 2%. The temperature sensitivity is about -1.5% per degree Celsius.

ADM, mechanical ventilation, respiration, silicon flow sensor
dx.doi.org/10.1109/10.552250, hdl.handle.net/1765/62978
I E E E Transactions on Biomedical Engineering
Department of Surgery

van Putten, M.J.A.M, van Putten, M.H.P.M, van Putten, A.F.P, Pompe, J.C, & Bruining, H.A. (1997). A silicon bidirectional flow sensor for measuring respiratory flow. I E E E Transactions on Biomedical Engineering, 44(2), 205–208. doi:10.1109/10.552250