An Unusual Pattern of Dyssynchronous Breathing due to Expiratory Flow Obstruction in the Scavenging System Caused by the Weight of Water Condensate.

Background: Patient-ventilator dyssynchrony is commonly due to patient pathophysiologic factors and imprecise ventilator settings. In unusual circumstances, such dyssynchrony can also be due to faults within the equipment preventing from its normal operation during assisted mechanical ventilation.

Case Description: We report a patient showing an unusual pattern of dyssynchronous breathing related to a blocked scavenging system caused by the failure of its rod valve to open. Collection of water condensate inside its reservoir bag leading to a weight drag and deformation of its shape was found to be the cause. Specifically, our patient manifested as failure to trigger with the development of high positive end-expiratory pressure (PEEP) and paradoxical pressure changes during pressure support ventilation.

Conclusion: Water condensation distal to the ventilator exhaust gas outlet may not be immediately apparent. Clinicians should remain alert with patient-ventilator dyssynchrony, especially with an unusual pattern, as it may signify equipment faults, such as expiratory gas flow obstruction within the scavenging system.

How To Cite This Article: Chan KM, Ng YC, So HY. An Unusual Pattern of Dyssynchronous Breathing due to Expiratory Flow Obstruction in the Scavenging System Caused by the Weight of Water Condensate. Indian J Crit Care Med 2020;24(11):1128-1131.