Methodology Score: 3.5/5
Usefulness Score: 3/5
Question and Methods: This single centre, un-blinded RCT compared oxygen saturation levels for apneic oxygenation versus usual car in ED patients undergoing RSI intubation.
Findings: No difference between the two groups in the lowest mean desaturation, or in any secondary outcomes.
Limitations: Small sample size, use of a surrogate endpoint, and lack of patients with difficult intubations, prolonged apneic times, or insufficient pre-oxygenation.
Interpretation: Apneic oxygenation doesn’t do much for the majority of RSI patients, but it’s a cheap, easy intervention with minimal harm, so why not keep doing it for that occasional unpredictable difficult airway?
By: Dr. Thara Kumar
The sample size of a clinical trial must be adequately powered to show a minimal clinically important difference (MCID) between the intervention and control arms. MCID is the absolute difference in outcome proportions that would have to be shown the study intervention for clinicians to accept the new treatment as better. In an effort to keep sample size low, investigators sometimes estimate an MCID much larger than is reasonable or use an outcome that is not the most important, e.g. 4-hour survival rather than survival to discharge.
By: Dr. Ian Stiell