Pre-hospital endotracheal intubation in severe traumatic brain injury: ventilation targets and mortality-a retrospective analysis of 308 patients

Jürgen Knapp; Pascal Doppmann; Markus Huber; Lorenz Meuli; Roland Albrecht; Stephen Sollid; Urs Pietsch

doi:10.1186/s13049-023-01115-8

Pre-hospital endotracheal intubation in severe traumatic brain injury: ventilation targets and mortality-a retrospective analysis of 308 patients

Scand J Trauma Resusc Emerg Med. 2023 Sep 12;31(1):46. doi: 10.1186/s13049-023-01115-8.

Authors

Jürgen Knapp^#^{1

2}, Pascal Doppmann^#^{3

4

5}, Markus Huber⁶, Lorenz Meuli⁷, Roland Albrecht^{3

8}, Stephen Sollid^{9

10}, Urs Pietsch^{8

11}

Affiliations

¹ Department of Anaesthesiology and Pain Medicine, Bern University Hospital, Inselspital, University of Bern, 3010, Bern, Switzerland. Juergen.knapp@insel.ch.
² Swiss Air-Rescue (Rega), Zurich, Switzerland. Juergen.knapp@insel.ch.
³ Swiss Air-Rescue (Rega), Zurich, Switzerland.
⁴ Department of Anaesthesiology and Pain Medicine, University Hospital Basel, Basel, Switzerland.
⁵ Faculty of Medicine, University of Bern, Bern, Switzerland.
⁶ Department of Anaesthesiology and Pain Medicine, Bern University Hospital, Inselspital, University of Bern, 3010, Bern, Switzerland.
⁷ Department of Vascular Surgery, University Hospital Zürich, Zurich, Switzerland.
⁸ Department of Emergency Medicine, Bern University Hospital, Inselspital, University of Bern, Bern, Switzerland.
⁹ Division of Prehospital Services, Oslo University Hospital, Oslo, Norway.
¹⁰ Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.
¹¹ Department of Anaesthesiology and Intensive Care Medicine, Cantonal Hospital St. Gallen, St. Gallen, Switzerland.

^# Contributed equally.

Abstract

Background: Traumatic brain injury (TBI) remains one of the main causes of mortality and long-term disability worldwide. Maintaining physiology of brain tissue to the greatest extent possible through optimal management of blood pressure, airway, ventilation, and oxygenation, improves patient outcome. We studied the quality of prehospital care in severe TBI patients by analyzing adherence to recommended target ranges for ventilation and blood pressure, prehospital time expenditure, and their effect on mortality, as well as quality of prehospital ventilation assessed by arterial partial pressure of CO₂ (PaCO₂) at hospital admission.

Methods: This is a retrospective cohort study of all TBI patients requiring tracheal intubation on scene who were transported to one of two major level 1 trauma centers in Switzerland between January 2014 and December 2019 by Swiss Air Rescue (Rega). We assessed systolic blood pressure (SBP), end-tidal partial pressure of CO₂ (PetCO₂), and PaCO₂ at hospital admission as well as prehospital and on-scene time. Quality markers of prehospital care (PetCO₂, SBP, prehospital times) and prehospital ventilation (PaCO₂) are presented as descriptive analysis. Effect on mortality was calculated by multivariable regression analysis and a logistic general additive model.

Results: Of 557 patients after exclusions, 308 were analyzed. Adherence to blood pressure recommendations was 89%. According to PetCO_2, 45% were normoventilated, and 29% had a SBP ≥ 90 mm Hg and were normoventilated. Due to the poor correlation between PaCO₂ and PetCO₂, only 33% were normocapnic at hospital admission. Normocapnia at hospital admission was strongly associated with reduced probability of mortality. Prehospital and on-scene times had no impact on mortality.

Conclusions: PaCO₂ at hospital admission is strongly associated with mortality risk, but normocapnia is achieved only in a minority of patients. Therefore, the time required for placement of an arterial cannula and prehospital blood gas analysis may be warranted in severe TBI patients requiring on-scene tracheal intubation.

Keywords: HEMS; Prehospital emergency medicine; Tracheal intubation; Traumatic brain injury; Ventilation.

MeSH terms

Brain Injuries, Traumatic* / therapy
Carbon Dioxide*
Hospitals
Humans
Intubation, Intratracheal
Retrospective Studies

Substances

Carbon Dioxide