Impact of endotracheal intubation versus laryngeal tube on gasometry and lactate at emergency department admission after out-of-hospital cardiac arrest

Abstract

Aim: Guidelines recommend supraglottic airways (e.g. laryngeal tube, LT) for out-of-hospital cardiac arrest (OHCA) if providers are not skilled in endotracheal intubation (ETI). In prolonged cardiopulmonary resuscitation (CPR) LT led to asphyxial physiology. Therefore we evaluated the impact of LT vs. ETI on gasometry and lactate at admission. Methods: All patients from 1 January 2020 to 30 April 2023 with return of spontaneous circulation (ROSC) or ongoing CPR (no ROSC) were included in this retrospective cohort study.Continuous data were analysed using the Mann-Whitney-U-Test. Results: Overall, 147 patients were included: ETI, n = 104; LT, n = 33; other airways, n = 10. ROSC, n = 86; no ROSC, n = 61. ETI vs. LT (median) for all patients showed: arterial blood gas analyses (BGA) (n = 62 vs. n = 20): pH 7.01 vs. 7.07, p = 0.83; pCO2 64.5 vs. 66.6 mmHg, p = 0.62; lactate 10.1 vs. 9.5 mmol/l, p = 0.68. Venous BGA (n = 37 vs. n = 11): pH 6.91 vs. 7.12, p = 0.15; pCO2 77.4 vs. 66.0 mmHg, p = 0.19; lactate 11.5 vs. 8.6 mmol/l, p = 0.24. ROSC, arterial BGA (n = 39 vs. n = 12): pH 7.09 vs. 7.14, p = 0.36; pCO2 60.3 vs. 56.4 mmHg, p = 0.84; lactate 8.95 vs. 7.0 mmol/l, p = 0.35. No ROSC, arterial BGA (n = 23 vs. n = 8): pH 6.9 vs. 6.8, p = 0.03; pCO2 80.7 vs. 85.6 mmHg, p = 0.64; lactate 13.0 vs. 14.6 mmol/l, p = 0.62. Conclusion: The prehospital airway strategy had no impact on gasometry in this OHCA collective except a better pH with ETI in no ROSC. Due to small numbers and non-existent data about the exact prehospital ventilation parameters, further prospective studies are needed to evaluate this question.

Keywords

• Out-of-hospital cardiac arrest
• Endotracheal intubation
• Laryngeal tube
• Gasometry
• Physiology