Post-induction hypotension during rapid sequence intubation in the operating room: A post hoc analysis of the randomized controlled REMICRUSH trial

Abstract

Background: We explored the risk factors of post-induction hypotension during rapid sequence intubation.

Methods: We performed an ancillary analysis of a multicenter randomized clinical trial comparing remifentanil versus neuromuscular blockers associated with hypnotic in patients at risk for aspiration who underwent tracheal intubation in the operating room. The primary outcome was post-induction hypotension, defined as an episode of hypotension (MBP ≤ 55 mmHg and/or SBP ≤ 80 mmHg) within 10 min after anesthetic induction.

Results: From 15 hospitals, 1137 adult patients were included, and 291 (26%) had post-induction hypotension. Propofol was used in 1117 (98%) patients and was associated with low doses of ketamine in 209 (18 %) patients. The independent risk factors associated with post-induction hypotension were age (OR 1.03, 95% CI [1.02; 1.04] p < 0.0001), baseline heart rate (p = 0.0068), bowel occlusion requiring nasogastric tube placement before intubation (OR 1.96, 95% CI [1.33; 2.87] p = 0.0006) and use of remifentanil (OR 3.54, 95%CI (2.61; 4.81) p < 0.0001). Use of low doses of ketamine (OR 0.61, 95% CI [0.41; 0.92] p = 0.0175) and basal SBP (OR 0.98, 95% CI [0.97; 0.99] p < 0.0001) were protective factors. The precision of the final model including the above-mentioned variables gave an AUC of 0.74 [95% CI 0.71; 0.77] for post-induction hypotension prediction.

Conclusions: Post-induction hypotension was frequent during rapid sequence intubation. Sedation associating propofol with low doses of ketamine was associated with a low risk of post-induction hypotension. Further studies are required to demonstrate a causal effect.

Registration: ClinicalTrials.gov NCT03960801.

Keywords: General anesthesia; Ketamine; Post-induction hypotension; Propofol; Rapid sequence intubation; Risk factors.