Dynamic measurement

A pressure-volume loop may be viewed on most modern mechanical ventilators. A square wave inspiratory waveform (constant flow) and no inspiratory pause are necessary for waveform interpretation.

static measurement

Small incremental lung volumes (200ml) are delivered with a calibrated syringe. The pressure measurement after each increment is taken under zero flow conditions, allowing construction of a pressure-volume curve. A quasistatic curve can be constructed by setting incremental tidal volumes (e.g. between 100 and 1000ml) for successive ventilator breaths and measuring the pressure during an inspiratory pause.

0 0

Post a comment