Exploration of alive-and-ventilator free days as an outcome measure for clinical trials of Resuscitative interventions

by Ari Moskowitz, Xianhong Xie, Michelle Ng Gong, Henry E. Wang, Luke Andrea, Yungtai Lo, Mimi Kim, for the Hospital Airway Resuscitation Trial Investigators

Background

Outcome selection is a critically important aspect of clinical trial design. Alive-and-ventilator free days is an outcome measure commonly used in critical care clinical trials, but has not been fully explored in resuscitation science.

Methods

A simulation study was performed to explore approaches to the definition and analysis of alive-and-ventilator free days in cardiac arrest populations. Data from an in-hospital cardiac arrest observational cohort and from the Pragmatic Airway Resuscitation Trial were used to inform and conduct the simulations and validate approaches to alive-and-ventilator free days measurement and analysis.

Findings

Alive-and-ventilator-free days is a flexible outcome measure in cardiac arrest populations. An approach to alive-and-ventilator free days that assigns -1 days when return of spontaneous circulation is not achieved provides a wider distribution of the outcome and improves statistical power. The optimal approach to the analysis of alive-and-ventilator free days varies based on the expected impact of the intervention under study on rates of return of spontaneous circulation, survival, and ventilator-free survival.

Conclusions

Alive-and-ventilator free days adds to the armamentarium of clinical trialists in the field of resuscitation science.