Are ventilators safe to prevent accidental lung trauma?

Abstract

It is well recognised that sometimes an anaesthetist forget to switch from breathing bag mode to mechanical ventilation. Technical valve errors, occluded expiratory tubing can happen also. The goal of this study was to evaluate the performance of eight ventilators in the breathing bag mode without compressing the breathing bag with an APL valve and an alarm set at their maximum value. The airway pressure and the time it took for the alarm to sound were measured. An American breathing bag was connected. Fresh gas flow was set at 12 litres per minute. Each ventilator was connected to an artificial lung.. And a compliance of 23 ml/cmH 2 O. A ventilator was considered at risk if the artificial lung inflated above 20 cmH 2 0 for more than 5 seconds. It was considered dangerous if no alarm did go off in that time.All ventilators were considered at risk and most considered dangerous.