Flow separation, an important mechanism in the formation of mean pulmonary pressure during high-frequency oscillation.

摘要: Mean pressures within the lungs and lung volume, respectively, are clinically important parameters. During ventilation by way of high-frequency oscillation (HFO), these parameters have been shown to be strongly frequency dependent. To identify mechanisms leading mean pressure formation during HFO, findings theory stationary flow were extended oscillatory a quasi-stationary approach. confirm theoretical findings, in-vitro experiments on HFO-models performed. Flow separation was found an mechanism in pressure. causes significant resistance, which may distinctly different for in- outflow. flow, difference thus results. This is particular importance bifurcations, present HFO-circuit as well airways. With direction-dependent separation, general found, accounts differing values with HFO-circuits. also contributes interregionally lungs.