(921) Hemodynamic Impact of Etomidate vs Ketamine for Rapid Sequence Intubation in Normotensive Patients

Introduction: Consideration must be given to the hemodynamic effect of induction agents administered prior to rapid sequence intubation (RSI). Etomidate (ETO) is the predominant induction agent in RSI; however, conflicting data exists supporting the role of ketamine (KET) as an alternative to ETO, particularly in normotensive patients. This study evaluated the impact of ETO versus KET on systolic blood pressure (SBP) when utilized as induction agents for RSI.

Methods: This single-center, retrospective cohort study included adult patients between 4/2016-3/2024 who received ETO or KET as induction agents prior to RSI in the emergency department. Patients were excluded with pre-intubation hypotension (SBP < 90 mmHg) or cardiac arrest at presentation. Patients were case matched 1:1 on induction agent and admitting diagnosis. The primary outcome was incidence of post-intubation hypotension (SBP < 90 mmHg) within 90-minutes after induction agent administration. Secondary outcomes included change in SBP before versus after induction agent administration, as well as time to vasopressor and subsequent sedative agent initiation. SPSS was used for statistical analysis.

Results: Of the 1581 patients screened, 58 patients (29 ETO,29 KET) met inclusion criteria, 58% male, with the most common admitting diagnoses being respiratory failure (34%) and infection (26%). Majority of patients (62%) received rocuronium after induction. Baseline pre-intubation SBP was similar between groups, 138±37 ETO vs 133±38 KET, mmHg, p=0.62. No difference was seen in post-intubation hypotension between groups, 21% ETO vs 21% KET, p=0.99. Absolute change in SBP from time of induction to 90-minutes was not different, -7.6[-25.0,3.6] ETO vs 0[-27.6,13.3] KET, mmHg, p=0.49. SBP pre- vs post-intubation for ETO and KET was not different, respectively, ETO 138±37 vs 142±44, mmHg, p=0.57; KET 133±38 vs 130±32, mmHg, p=0.61. No differences were seen regarding the need for vasopressor initiation within 24-hours after induction, 12% ETO vs 9% KET, p=0.74.

Conclusions: Hemodynamic stability is important to maintain when performing RSI. This study suggests that, in normotensive patients, receiving ETO or KET for RSI induction had a neutral effect on SBP within 90-minutes after intubation with no differences in episodes of SBP < 90 mmHg.