Propensity for performing interventions in pre-hospital trauma management - a comparison between physicians and non-physicians.

Background: In 2005, the Advanced Life Support (ALS) teams delivering pre-hospital care in RegionSkane in southern Sweden received additional support by physicians, who were part of "Pre-hospital acute teams" (PHAT). The study objective is to compare the incidence of pre-hospital medical interventions for trauma-patients cared for by conventional ALS teams and patients who received additional support by PHAT.
Methods: Trauma patients with Injury Severity Score (ISS) >9 were identified retrospectively in the national quality registry KVITTRA at three hospitals in RegionSkane, for the time period October 2005 to December 2008. Interventions include e.g. tracheal intubation, administration of i.v. fluids, neck immobilization and spine board usage. Confounding effects from trauma severity, trauma mechanism, vital parameters, age and sex were addressed in multivariate models.
Results: Data from 202 cases was included. 9 pre-hospital interventions were assessed. The incidence of endotracheal intubation and immobilisation of extremities was higher among patients in the PHAT-group compared to the ALS-only group (16.3% vs. 6.9%, p = 0.034) and (12.8% vs. 4.3%, p = 0.027) respectively. PHATs presence remained a significant predictor of these interventions also after taking confounding factors into account (OR 5.5, CL 1.5-19.7) and (OR 3.2 CI 1.0-9.8).PHAT was involved in a greater proportion of cases with <50.0% of survival (19.8% vs. 12.1%, p = 0.134). The average ISS was higher among cases receiving PHAT support in strata ISS 16-24 and ISS > 24 than cases in corresponding strata cared for by ALS teams alone (ISS 20.0 vs. 17.0, p = 0.048 and ISS 34.0 vs. 29.0, p = 0.019).
Conclusions: The incidence of endotracheal intubation and immobilization of extremities was greater among patients supported by PHAT, compared to patients cared for by ALS teams alone. This finding has to be interpreted in the light of a selection-bias where PHAT support was directed to more severely injured patients.