Flow-Limited and Reverse-Triggered Ventilator Dyssynchrony Are Associated With Increased Tidal and Dynamic Transpulmonary Pressure

Abstract

Objectives: Ventilator dyssynchrony may be associated with increased delivered tidal volumes (Vts) and dynamic transpulmonary pressure (ΔPL,dyn), surrogate markers of lung stress and strain, despite low Vt ventilation. However, it is unknown which types of ventilator dyssynchrony are most likely to increase these metrics or if specific ventilation or sedation strategies can mitigate this potential. Design: A prospective cohort analysis to delineate the association between ten types of breaths and delivered Vt, ΔPL,dyn, and transpulmonary mechanical energy. Setting: Patients admitted to the medical ICU. Patients: Over 580,000 breaths from 35 patients with acute respiratory distress syndrome (ARDS) or ARDS risk factors. Interventions: None. Measurements and Main Results: Patients received continuous esophageal manometry. Ventilator dyssynchrony was identified using a machine learning algorithm. Mixed-effect models predicted Vt, ΔPL,dyn, and transpulmonary mechanical energy for each type of ventilator dyssynchrony while controlling for repeated measures. Finally, we described how Vt, positive end-expiratory pressure (PEEP), and sedation (Richmond Agitation-Sedation Scale) strategies modify ventilator dyssynchrony’s association with these surrogate markers of lung stress and strain. Double-triggered breaths were associated with the most significant increase in Vt, ΔPL,dyn, and transpulmonary mechanical energy. However, flow-limited, early reverse-triggered, and early ventilator-terminated breaths were also associated with significant increases in Vt, ΔPL,dyn, and energy. The potential of a ventilator dyssynchrony type to increase Vt, ΔPL,dyn, or energy clustered similarly. Increasing set Vt may be associated with a disproportionate increase in high-volume and high-energy ventilation from double-triggered breaths, but PEEP and sedation do not clinically modify the interaction between ventilator dyssynchrony and surrogate markers of lung stress and strain. Conclusions: Double-triggered, flow-limited, early reverse-triggered, and early ventilator-terminated breaths are associated with increases in Vt, ΔPL,dyn, and energy. As flow-limited breaths are more than twice as common as double-triggered breaths, further work is needed to determine the interaction of ventilator dyssynchrony frequency to cause clinically meaningful changes in patient outcomes.