Comparison of Esketamine and Propofol for Prehospital Emergency Anaesthesia in Patients With Traumatic Brain Injury-A Retrospective Observational Study.

BACKGROUND

Prehospital emergency anaesthesia and controlled ventilation are cornerstones in the treatment of traumatic brain injury patients. Currently, there is a lack of consensus regarding the choice of anaesthetic used during the induction of anaesthesia. Esketamine has gained significant popularity, but its use has been limited in patients with traumatic brain injury due to fears of increased intracranial pressure. A protocol for anaesthesia was implemented at a Finnish helicopter emergency medical services (HEMS) unit during 2015 that mandated the use of esketamine over propofol for most patients.

METHODS

We performed a retrospective cohort study to evaluate the differences in mortality and physiology in patients with traumatic brain injury, intubated using either propofol or esketamine. We collected data on patients treated by a single HEMS unit in Finland between January 2014 and December 2021. Our primary outcome was mortality before hospital discharge, and our secondary outcome was physiological stability, defined as the frequency of hypotension (systolic blood pressure ≤ 90 mmHg or a decrease of ≥ 10%) after intubation. Controlling for confounders was done through a logistical regression analysis.

RESULTS

We identified a total of 366 patients, 301 of whom were treated with esketamine and 65 with propofol. There was no significant difference in mortality between the esketamine and propofol groups (odds ratio 0.598, 95% confidence interval 0.281-1.272). The decrease in blood pressure after intubation was greater in the propofol group (absolute change -37.3 vs. -12.4 mmHg, 95% confidence interval -38 to -15 mmHg), but because the initial blood pressure was also higher, both groups had similar postintubation physiology.

CONCLUSION

In this study, we found no significant difference in mortality, but we found significant differences in the haemodynamic responses between esketamine and propofol, with a slightly favourable haemodynamic profile in patients treated with esketamine. The protocol implemented in 2015 heavily shifted the choice of anaesthetics from propofol to esketamine, but there was a distinct resurgence in propofol use during the study period.

EDITORIAL COMMENT: Patients with severe head injuries can receive advance intensive care including anaesthetic drugs in the field for intubation, when prehospital teams have this competence. This retrospective analysis presents a comparison of outcomes for traumatic brain injury cases who received either propofol or esketamine in the prehospital setting, as part of a time-interrupted series where drug choice was changed. While possibly differing in circulatory effects, the two drugs were not associated with a difference in mortality before hospital discharge.