Introduction: Delayed Sequence Intubation (DSI) is an airway management technique that improves oxygenation in patients who are resistant to conventional preoxygenation. Unlike Rapid Sequence Intubation (RSI), DSI separates the administration of sedatives from paralytics, allowing patients to remain sedated while maintaining spontaneous respirations. While prior studies have demonstrated the benefits of DSI in select populations, data comparing its safety to RSI remains limited. This study aims to compare peri-intubation complications between DSI and RSI in a diverse patient population. Methods: We conducted a retrospective analysis of a prospectively maintained airway registry at a large tertiary care ED from June 2017 to December 2024. We reviewed DSI and RSI cases to track peri-intubation complications and first-pass success (FPS). Variables included demographics, technique, and airway difficulty. The primary outcome included rate of peri-intubation cardiac arrest and desaturation events. Secondary outcomes included supraglottic airway use, cricothyrotomy rate, post-induction vomiting and FPS rates. Results: We included 2,254 patients: 190 DSI and 2,064 RSI. Desaturation occurred more often in DSI (5.8% vs. 3.4%; RR 1.7, p=0.10) but was not significant. Cardiac arrest (1.3% vs. 0.6%; RR 2.2, p=0.24) and cricothyrotomy (1.1% vs. 0.4%; RR 2.7, p=0.24) were more frequent in DSI but not significant. Vomiting (0.5% both, p=1.0) and supraglottic airway use (1.1% vs. 1.8%; p=0.58) were similar. FPS remained high: 95.8% in DSI vs. 93.3% in RSI (RR 1.03, p=0.21). DSI had a significantly higher rate of anticipated difficult airway (56.3% vs. 18.7%; RR 3.0, p< 0.001). Conclusions: Peri-intubation complication rates in the DSI group were similar to those in the RSI group. Desaturation and cardiac arrest rates were higher in the DSI group, but these differences were not statistically significant. DSI patients represent a critically ill subgroup, requiring contextual interpretation. Secondary outcomes were comparable between groups. DSI had similar FPS despite more frequent difficult airway designation. While a randomized trial would be ideal, the infrequent use and high-risk nature of DSI limit feasibility. Future research should explore multi-center studies, induction agents, and system-wide performance tracking.
Leibowitz et al. (Sun,) studied this question.