BACKGROUND
Whether intubation should be initiated early in the clinical course of critically ill patients remains a matter of debate. Results from prior observational studies are difficult to interpret because of avoidable flaws including immortal time bias, inappropriate eligibility criteria, and unrealistic treatment strategies.
RESEARCH QUESTION
Do treatment strategies that intubate patients early in their critical care admission improve 30-day survival compared to strategies that delay intubation?
STUDY DESIGN AND METHODS
We estimated the effect of strategies that require early intubation of critically ill patients compared to those that delay intubation. With data extracted from the Medical Information Mart for Intensive Care-IV database, we emulated three target trials, varying the flexibility of the treatment strategies and the baseline eligibility criteria.
RESULTS
Under unrealistically strict treatment strategies with broad eligibility criteria, the 30-day mortality risk was 7.1 percentage points higher for intubating early compared to delaying intubation [95% CI, 6.2, 7.9]. Risk differences were 0.4 [95% CI, -0.1, 0.9] and -0.9 [95% CI, -2.5, 0.7] percentage points in subsequent target trial emulations which included more realistic treatment strategies and eligibility criteria.
INTERPRETATION
When realistic treatment strategies and eligibility criteria are used, strategies that delay intubation result in similar 30-day mortality risks compared to those that intubate early. Delaying intubation ultimately avoids intubation in most patients.