Figure 2From: Expiratory time constant for determinations of plateau pressure, respiratory system compliance, and total resistanceDetermination of expiratory time constant. Example of determining the expiratory time constant (ƬE) for one patient in the study is shown. ƬE was determined by point-by-point analyses of exhaled tidal volume (VT) and flow rate values between 0.10 and 0.50 seconds, that is, the exhaled VT and flow rate curves are substituted by a fitted straight line (least squares fit) and the slope of the line is ƬE.Back to article page