The OPALS Major Trauma Study: impact of advanced life-support on survival and morbidity

Abstract

Background: To date, the benefit of prehospital advanced life-support programs on trauma-related mortality and morbidity has not been established

Methods: The Ontario Prehospital Advanced Life Support (OPALS) Major Trauma Study was a before-after systemwide controlled clinical trial conducted in 17 cities. We enrolled adult patients who had experienced major trauma in a basic life-support phase and a subsequent advanced life-support phase (during which paramedics were able to perform endotracheal intubation and administer fluids and drugs intravenously). The primary outcome was survival to hospital discharge.

Results: Among the 2867 patients enrolled in the basic life-support (n = 1373) and advanced life-support (n = 1494) phases, characteristics were similar, including mean age (44.8 v. 47.5 years), frequency of blunt injury (92.0% v. 91.4%), median injury severity score (24 v. 22) and percentage of patients with Glasgow Coma Scale score less than 9 (27.2% v. 22.1%). Survival did not differ overall (81.1% among patients in the advanced life-support phase v. 81.8% among those in the basic life-support phase; p = 0.65). Among patients with Glasgow Coma Scale score less than 9, survival was lower among those in the advanced life-support phase (50.9% v. 60.0%; p = 0.02). The adjusted odds of death for the advanced life-support v. basic life-support phases were nonsignificant (1.2, 95% confidence interval 0.9-1.7; p = 0.16).

Interpretation: The OPALS Major Trauma Study showed that systemwide implementation of full advanced life-support programs did not decrease mortality or morbidity for major trauma patients. We also found that during the advanced life-support phase, mortality was greater among patients with Glasgow Coma Scale scores less than 9. We believe that emergency medical services should carefully re-evaluate the indications for and application of prehospital advanced life-support measures for patients who have experienced major trauma.

Figure 1: Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) evaluating factors associated with mortality at hospital discharge. Model incorporates study phase and final (hospital) revised trauma score as predictors of mortality. Goodness-of-fit: p > 0.20. *Final assessment of revised trauma score represents value from lead trauma hospital; if missing, the value from the scene was used. †Time from call received to arrival of crew at patient side.

Figure 2: Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) evaluating factors associated with mortality at hospital discharge. Model incorporates study phase and initial (field) revised trauma score as predictors of mortality. Goodness-of-fit: p > 0.20. *Initial assessment of revised trauma score represents value from the scene; if missing, the value from the lead trauma hospital was used. †Time from call received to arrival of crew at patient side.

Figure 3: Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) evaluating factors associated with mortality at hospital discharge. Model incorporates advanced life-support provided at the scene as predictor of mortality. Goodness-of-fit: p > 0.20. *Initial assessment of revised trauma score represents value from the scene; if missing, the value from the lead trauma hospital was used. †Time from call received to arrival of crew at patient side.

Figure 4: Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) evaluating factors associated with mortality at hospital discharge. Model incorporates advanced life-support interventions as predictors of mortality. Goodness-of-fit: p > 0.20. *Initial assessments of Glasgow Coma Scale score and systolic blood pressure represent values from the scene; if missing, the value from the lead trauma hospital was used. †Time from call received to arrival of crew at patient side.