Isolated blunt severe traumatic brain injury in Bern, Switzerland, and the United States: A matched cohort study.

BACKGROUND: The ideal prehospital management of patients with severe traumatic brain injury (TBI) including the impact of endotracheal intubation (ETI) and physicians on scene is unclear. Prehospital management differs substantially in Switzerland and the United States: in Switzerland, there is usually a physician on scene who may provide ETI and other advanced life support procedures, whereas in the United States, prehospital management (including ETI) is performed by paramedics.

METHODS: This is a retrospective cohort-matched study of patients with isolated blunt severe TBI (head Abbreviated Injury Scale [AIS] score, 4-5) and no major extracranial injuries, using Bern University Hospital data from the Swiss PEBITA [Patient-relevant Endpoints after Brain Injury from Traumatic Accidents] (TBI-specific) database and the US National Trauma Data Bank from 2009 to 2010. A 1:4 cohort matching of Bern and US patients was performed. Matching criteria were sex, age (±10 years), exact field Glasgow Coma Scale (GCS) score, exact head AIS score, and injury type (subdural hematoma, epidural hematoma, intraparenchymal hemorrhage, intraventricular hemorrhage, brain edema/swelling, brain stem injury). The matched cohorts were compared with univariable analysis (Fisher's exact test and Mann-Whitney U-test).

RESULTS: Matching of the Bern (n = 128) and US (n = 86,375) cohort resulted in 355 matched cases (71 Bern and 284 US patients). Bern patients had significantly longer scene times (median, 23.0 minutes vs. 9.0 minutes, p < 0.001) and more frequent prehospital ETI (31.0% vs. 18.7%, p = 0.034) and air transportation (39.4% vs. 19.4%, p < 0.001). No significant difference in procedures (craniotomy/craniectomy, intracranial pressure monitoring, tracheotomy), intensive care unit and total hospital lengths of stay, ventilator days, and in-hospital mortality (14.1% vs. 15.8%, p = 0.855) was found between the two cohorts.

CONCLUSION: When taking into account the limitation that patient- and injury-related factors, but not in-hospital treatment variables, were matched, the more frequent prehospital ETI and presence of a physician on scene in the Swiss cohort compared with the US cohort had no significant effect on outcomes, including intensive care unit and total hospital lengths of stay, ventilator days, and in-hospital mortality.

LEVEL OF EVIDENCE: Therapeutic study, level IV.