Frequency and significance of post-intubation hypotension during emergency airway management

Introduction

Arterial hypotension is known to follow emergency intubation but the significance of this event is poorly described. We aimed to measure the incidence of post-intubation hypotension (PIH) following emergency intubation and determine its association with in-hospital mortality.

Methods

A retrospective cohort study of endotracheal intubations performed in a large, urban emergency department over a 1-year period. Patients were included if they were >17 years old and had systolic blood pressure (SBP) >90 mmHg for 30 consecutive minutes prior to intubation. Patients were analyzed in two groups: those with PIH defined by SBP <90 mmHg within 60 minutes of intubation, and those with no PIH. The primary outcome was hospital mortality.

Results

Emergency intubation was performed on 465 patients, of which 336 met inclusion criteria and were analyzed. The median patient age was 49 years, 59% of patients presented with nontraumatic illness and 92% underwent induction with etomidate. PIH occurred in 76/336 (23%) of patients. The median time to first PIH was 11 minutes (IQR 2 to 27). Intubation for acute respiratory failure was the only independent predictor of PIH (OR = 2.1, 95% CI = 1.1 to 4.0). Patients with PIH had significantly higher in-hospital mortality (33% vs. 21%; 95% CI for 12% difference = 1 to 23%) and longer mean ICU length of stay (9.7 vs. 5.9 days, P < 0.01) and hospital length of stay (17.0 vs. 11.4 days, P < 0.01). Multivariate logistic regression analysis confirmed PIH as an independent predictor of hospital mortality (OR = 1.9, 95% CI = 1.1 to 3.6).

Conclusions

PIH occurs in nearly one-quarter of normotensive patients undergoing emergency intubation. Intubation for acute respiratory failure is an independent predictor of PIH. PIH is associated with a significantly higher in-hospital mortality and longer ICU and hospital lengths of stay.