In a study published in Annals of Surgery, a comparison of emergency medical service (EMS)-transported patients versus non-EMS-transported patients was made; this was a prospective cohort-matched observation study. All non-EMS patients that arrived at a level 1 trauma center were matched with the next appropriate EMS trauma patient by an investigator who was unaware of the mode of transport and the outcomes of the patient; in addition, every tenth EMS patient with an injury severity score of more than 13 was also enrolled. An interview process with patients, witnesses, and friends was used to determine the time of injury and the study outcome designed to determine the time to hospital, mortality, morbidity, and length of hospital stay. A total of 103 patients were enrolled; deaths, complications, and length of hospital stay were similar in both groups purporting to suggest that prehospital EMS had little effect on patient outcome. An interesting analysis demonstrated that for the more severe trauma patients (defined as those with an injury severity score of equal to or greater than 13), the non-EMS-transported patients managed to arrive at the trauma center in less time than those transported by EMS (15 min vs. 28 min; P < 0.05).

This study compared EMS versus non-EMS – not BLS versus ALS; the study also included both penetrating and blunt injury patients; conceptually one would think that for penetrating trauma such as a gunshot wound or stab to the torso, there is little that the prehospital personnel can provide other than rapid transport to the appropriate trauma center. A notation within the article stated that in none of the patients with penetrating injury was spinal immobilization even theoretically warranted. It should be noted that this study was an analysis of patients taken directly to the level 1 center; there is no information on outcomes of those severely injured patients that might have been taken to non-trauma facilities by non-EMS transport.

There have been older studies examining the outcomes of ALS in more rural areas; it might be considered that in urban areas with a short transport time to a level 1 trauma center, the outcomes might be improved because of the immediate availability of operating rooms, surgeons, and the blood bank, and in many studies, the transport time was less than 15 min. There have also been concerns about the effectiveness of prehospital intubation and intravenous fluids – please see other chapters as to the current controversy – such that in an urban environment, these skills are not usually required and may be detrimental.

A comprehensive review of the question “does advanced life support benefit patients” has been published. The article examines not only trauma patients but also medical conditions. The opinion of the authors is that there is poor evidence that ALS improves outcome for trauma patients in urban areas (indeed ALS may contribute to poorer outcomes), but it may be of benefit in rural areas with long transport times – hence the EMS paradox as noted above.

A publication in the Canadian Medical Journal would seemingly be now the definitive study on this topic. This was the Ontario prehospital ALS (OPALS) study – a before-and-after study involving 17 cities in Ontario, Canada; data on trauma patient outcome before and after ALS instituted was collected. There were 2,867 trauma patients in the study, 1,373 had prehospital BLS, and after initiation of ALS, further 1,494 patients were enrolled. The primary outcome was survival to hospital discharge. Comparison of the two groups showed similar age, blunt and penetrating injury ratio, median injury severity score, and severe head injury as measured by Glasgow Coma Scale. After implementation of the ALS program, results showed that despite system-wide implementation of ALS, there was no improvement in mortality or morbidity. Indeed in the patients with a Glasgow Coma Score of less than 9, survival was less with ALS (50.9 % vs. 60.0 %; P = 0.02). The authors conclude “Emergency medical services should carefully reevaluate the indications for and the application of prehospital advanced life support measures for patients who have experienced severe trauma.” This would seem to indicate that at least in the urban environment, BLS prehospital management of trauma – both blunt and penetrating – would have just as good outcomes as ALS and for severe head injuries better outcomes.

The use of tranexamic acid has been shown (the CRASH-2 study) to decrease mortality in severely injured patients; in a review article, there was evidence that the earlier the administration, the better the improved outcome would be. Administration of tranexamic acid by prehospital personnel has been shown to improve outcomes in the military environment; studies in the civilian population are ongoing but not yet published.