Prehospital care research can be very distressing. We see papers that say trauma patients and children do better if they are not intubated in the field. We read papers that say outcomes from CPR without rescue breathing are similar to those in which rescue breathing is used. We see more and more results that appear counterintuitive. Now for the latest such trial — the OPALS trauma study. In this before-and-after comparison, a large number of patients getting basic life support for prehospital trauma were compared with a group getting advanced life support trauma care. You guessed it: Survival to discharge was almost identical (81.8% vs. 81.1%).
Surely there must be some subset of patients in whom ALS was demonstrated to be superior to BLS. No. Will this study likely cause any changes in our system of prehospital care? No way. EMS agencies are too busy moving on to their next unproven project: the regionalization of stroke care. Anybody want to bet on the outcomes of this endeavor?
The OPALS Major Trauma Study: Impact of Advanced Life Support on Survival and Morbidity
Stiell IG, et al
BACKGROUND: Within large North American cities, provision of prehospital advanced life support has become relatively standard for patients sustaining major trauma, but its effectiveness has not been clearly established.
METHODS: In a before-and-after format, the 17-city Ontario Prehospital Advanced Life Support (OPALS) study compared outcomes in 1,373 adults with injury severity scores (ISS) above 12 who received BLS in the prehospital setting and 1,494 similar patients who received prehospital ALS.
RESULTS: The median ISS was 24 in the BLS phase and 22 in the ALS phase, and median revised trauma scores were 7.84 in both phases. Among patients managed during the ALS phase, 6.8 percent were intubated in the field (71.8% success rate), IV access was established in 63 percent (90.3% success rate), and 11.7 percent received IV fluid bolus therapy. The overall rate of survival to discharge was 81.8 percent during the BLS phase and 81.1 percent during the ALS phase, and corresponding mortality rates during the initial 24 hours after injury were 7.0 percent and 7.2 percent, respectively. No subgroup was identified with significantly better outcomes during the ALS phase, and patients with a Glasgow Coma Scale score below 9 had a lower survival rate during the ALS phase (51.2% vs. 60.1% during the BLS phase). Among patients who survived to discharge, there were no significant differences between the two phases in GCS scores or measures of functional independence.
CONCLUSIONS: The authors suggest that EMS systems should reevaluate the implementation of advanced life support programs for the prehospital care of patients sustaining major trauma.
Home AEDs: No Benefit
Speaking of apple pie and motherhood, here is a fascinating study regarding the use of home defibrillators in a subset of patients who may be at increased risk, those with a prior anterior MI. In the study, 3,495 got AEDs and 3,506 did not, and the results after a median follow-up of 37 months showed no difference in all-cause mortality when compared with conventional resuscitation methods.
Although the study was sponsored by the National Heart, Lung and Blood Institute, the defibrillators were provided free of charge by Philips Medical Systems (they retail for about $1,500 on their web site). Certainly there are many cases of individuals being saved by these devices, but given the cost and overall low yield, it would be tough to make the case for their widespread adoption in this subset of patients (although depending on your disposable income, people may choose to spend the money “just in case”).
Home Use of Automated External Defibrillators for Sudden Cardiac Arrest
Bardy GH, et al
N Engl J Med
BACKGROUND: Use of an automated external defibrillator by a trained lay responder may increase survival after sudden cardiac arrest. Three-quarters of sudden cardiac arrests occur in the home, however.
METHODS: In this multinational clinical trial, coordinated in Seattle, patients who were clinically stable following a previous anterior Q-wave or non- Q-wave myocardial infarction and who had a spouse or companion willing to take part were randomized to standard CPR training for their companion or additional training regarding use of an AED which was issued for home use. Candidates for implantable cardioverter-defibrillator therapy were excluded. Companions in both groups received extensive initial and follow-up training during the study period. The primary outcome measure was all-cause mortality over a median follow-up period of 37 months.
RESULTS: There were 7,001 patients randomized at 178 clinical sites in seven countries (3,495 in the AED group and 3,506 controls). The median patient age was 62 years, and 82 percent were male. The AED and control groups were comparable with regard to demographic and clinical variables. Overall, 450 patients died, including 6.5 percent of patients in the control group and 6.4 percent in the AED group. Of the 38 patients who were resuscitated from sudden cardiac arrest and survived at least 48 hours, 19 came from each of the two study groups, and in each group, eight of these 19 had experienced their cardiac arrest in their home. Among AED patients, 13 had a shock advised, of whom 12 had a shock delivered, and four were long-term survivors.
CONCLUSIONS: Access to a home AED did not improve outcomes among survivors of a previous anterior wall myocardial infarction.