Expiratory Muscle Relaxation-Induced Ventilator Triggering A Novel Patient-Ventilator Dyssynchrony

In critically ill patients receiving mechanical ventilation, expiratory muscles are recruited with high respiratory loading and/or low inspiratory muscle capacity. In this case report, we describe a previously unrecognized patient-ventilator dyssynchrony characterized by ventilator triggering by expiratory muscle relaxation, an observation that we termed expiratory muscle relaxation-induced ventilator triggering (ERIT). ERIT can be recognized with in-depth respiratory muscle monitoring as (1) an increase in gastric pressure (Pga) during expiration, resulting from expiratory muscle recruitment; (2) a drop in Pga (and hence, esophageal pressure) at the time of ventilator triggering; and (3) diaphragm electrical activity onset occurring after ventilator triggering. Future studies should focus on the incidence of ERIT and the impact in the patient receiving mechanical ventilation.

Automated summary

This case report describes a previously unrecognized patient-ventilator dyssynchrony called expiratory muscle relaxation-induced ventilator triggering (ERIT). It can be recognized with in-depth respiratory muscle monitoring.