Elastic static power, its correlation with acute respiratory distress syndrome severity: A Bayesian post-hoc analysis of the Mechanical Power Day cross-sectional trial.

Objective: The relationship between different power equations and the severity of acute respiratory distress syndrome (ARDS) remains unclear. This study aimed to evaluate various power equations: total mechanical power, total elastic power (comprising elastic static and elastic dynamic power), and resistive power, in a cohort of mechanically ventilated patients with and without ARDS. Bayesian analysis was employed to refine estimates and quantify uncertainty by incorporating a priori distributions.

Design: A Bayesian post-hoc analysis was conducted on data from the Mechanical Power Day study.

Setting: 113 intensive care units across 15 countries and 4 continents.

Patients: Adults who received invasive mechanical ventilation in volume-controlled mode, with (mild and moderate/severe ARDS) and without ARDS.

Interventions: None.

Main variables of interest: ARDS, Elastic static power.

Results: Elastic static power was 5.8 J/min (BF: 0.3) in patients with mild ARDS and 7.4 J/min (BF: 0.9) in moderate/severe ARDS patients. Bayesian regression and modeling analysis revealed that elastic static power was independently correlated with mild (a posteriori Mean: 1.3; 95% Credible Interval [Cred. Interval]: 0.2-2.2) and moderate/severe ARDS (a posteriori Mean: 2.8; 95% Cred. Interval: 1.7-3.8) more strongly than other power equations.

Conclusions: Elastic static power was found to have the strongest correlation with ARDS severity among the power equations studied. Prospective studies are needed to further validate these findings.