Effect of Noninvasive Ventilation Delivered by Helmet vs. Facemask on the Rate of Endotracheal Intubation in Patients with Acute Respiratory Distress Syndrome

Summary

Methodology Score: 4/5
Usefulness Score: 3.5/5

Patel BK, et al. JAMA. 2016 Jun 14;315(22):2435-41
Full Article

Editorial: Unmasking a Role for Noninvasive Ventilation in Early Acute Respiratory Distress Syndrome. Beitler JR, et al. JAMA. 2016 Jun 14;315(22):2401-3.

This single-centre, non-blinded RCT of ICU ARDS patients, found that noninvasive ventilation (NIV) delivered by a novel helmet, as compared to a standard NIV facemask, reduced intubations (18.2% vs. 61.5%; P <0.001) and hospital mortality (27.3% vs. 48.7%; P= 0.04). Despite its few methodological flaws, this study supports the existing literature on the advantage of oxygen delivered via helmet over facemask in avoiding intubation in ARDS, and future studies should focus on its impact in heart failure or hypercapneic respiratory failure.
By: Dr. Shannon Fernando 

Epi lesson:
Interim Analyses and Stopping Rules
In clinical trials, an interim analysis is one that is conducted before data collection has been completed to determine if there are safety issues or if the study should be stopped early. These interim analyses are evaluated by an independent Data Safety Monitoring Board that is at arm’s length from the investigators. The DSMB has the authority to recommend early termination if the study intervention is clearly better than control (for benefit) or if there is so little difference between groups that full enrolment will not show a difference (for futility). Statistical stopping rules should be used to adjust the interim P-values to a much severe level, e.g. <0.001 instead of <0.05 using methods described by Pocock and O’Brien & Fleming, among others.
By: Dr. Ian Stiell