From sirens to ALS, the medical literature continues to challenge pre-hospital dogma.
Apple pie and motherhood. That’s how EMS systems have come to be viewed in this country. While in some locations this is a well-deserved perception, in many others, local EMS systems have become out of step with medical evidence.
As the Associate Director of Paramedic Training for Los Angeles County several decades ago, I remember the extensive classroom and practical training provided to the students. If I recall correctly, the total number of hours of education was about 1,800. You can envision the level of detail that was achieved given this extensive amount of time. In retrospect we covered a huge amount of material that was essentially irrelevant to field care. But the goal was to assure a comprehensive level of training. The esprit de corps was high and being selected for the training was considered an honor.
It was generally assumed that paramedic-level care was the gold-standard for EMS. The huge popularity of the TV show, “Emergency!” which focused on three imaginary LA County paramedics in the 70s, catalyzed the nation’s interest in developing paramedic programs.
Yet, since those early days there has been a growing body of evidence suggesting that many of our assumptions about the best ways to provide prehospital care are very challengeable. From issues like the decreasing need for prehospital drug therapy (especially in the setting of a cardiac arrest) to evidence that little is gained by lights and sirens transport (and that it is associated with about 12,000 ambulance collisions annually in the U.S. and Canada) to the demonstrable overutilization of helicopter transport, the list of EMS practices that are worthy of scrutiny continues to grow.
But a much more fundamental question is arising. Perhaps less is more. Perhaps in some settings EMT-based rapid transport can result in better outcomes than ALS care. The next four papers challenge EMS agencies to look careful at the status quo.
EMS Commentary by Mike Levy, MD
EMS isn’t a single definable monolith but is in fact regulated at a state level and consequently from an administrative and legislative standpoint there are fundamental, sometimes huge, differences among EMS systems in different states. As we drill down, further differences in EMS include the size of systems, BLS versus ALS, fire-based, for-profit, volunteer, municipal third service, first responder only, air-medical etc. There is a growing body of high quality prehospital studies to help guide the practice. Even so, given the variability in how EMS is delivered and by whom, the generalizability of findings needs close scrutiny regarding how it applies to specific systems.
1. Bukata: This first study indicates trauma patients did better with BLS care than ALS care in an urban environment.
THE EVIL OF GOOD IS BETTER: MAKING THE CASE FOR BASIC LIFE SUPPORT TRANSPORT FOR PENETRATING TRAUMA VICTIMS IN AN URBAN ENVIRONMENT
Rappold, J.F., et al, J Trauma Acute Care Surg 79(3):343, September 2015
BACKGROUND: Some data suggest little advantage of advanced life support (ALS) over basic life support (BLS) during short emergency transport of trauma patients.
METHODS: This retrospective cohort study from Temple University in Philadelphia evaluated the effect of advanced versus basic life support during transport of 1,490 patients with penetrating trauma transported to an urban Level I trauma center by ALS (45% of patients; median age 27 years), BLS (15%; age 29 years), or police (40%; age 25 years). The primary outcome was the likelihood of death depending on both the type of transport and the type of care provision.
RESULTS: Most injuries were gunshot wounds. Both injury severity and transport time were significantly higher for ALS than for BLS (both p<0.03). On logistic regression adjusting for Injury Severity Score and transport time, the risk of death was higher in the ALS transport group than in the BLS group (odds ratio [OR], 1.86; 95% CI, 1.12-3.01) and with police versus BLS transport (OR 2.57; 95% CI, 1.61-4.11). Similarly, ALS care provision was associated with a higher odds of death than BLS care (OR, 2.51; 95% CI, 1.55-4.06). All of these significant differences applied only to trauma patients with less severe injury (ISS 30 or lower); differences were not significant among those with more severe injury. Study limitations include the nonrandomized design and missing data.
CONCLUSIONS: ALS transport and care were associated with decreased survival in patients with penetrating injuries and ISS scores below 30, and provided no significant benefit for patients with more severe injuries. It appears that speed of transport (ie, BLS care) is more important than the level of care provided.
13 references (JRappold@mmc.org for reprints) Copyright 2016 by Emergency Medical Abstracts – All Rights Reserved 2/16 – #28
The most notable major study on the impact of adding ALS to an all BLS system was the Ontario Prehospital Advanced Life Support Study (OPALS). OPALS was a multi-phase before and after EMS study conducted multiple Canadian communities in 11 base hospital regions that studied the effect on cardiac arrest(10,000 patients), major trauma(6000 patients) and respiratory distress(8000 patients) of adding ALS to BLS. These studies were initiated in the late 1990s and the final publications in the mid-2000’s. Overall, the study showed that ALS provided improved primary outcomes only for respiratory emergencies but did show numerous improvements in secondary outcomes in the ALS phase. These studies did cause a significant stir in the EMS community, questioning the value of ALS over BLS with no clear resolution. Confounding the outcome was the fact that the study added ALS to previously ALS-naïve system raising questions as to how newly minted ALS providers compared to seasoned ALS providers as well as the inherent differences in our health care system compared to Canada.
2. Bukata: A paper looking at survival of gunshot wound victims indicates that transport by private car is associated with better survival than EMS care. This concept is irreverently known as “home boy transport” in the Los Angeles barrio. But even decades ago it was common practice that when a policeman was shot, his colleagues would load him into the back seat of a patrol car and get him to the local hospital way before an ambulance would have even arrived at the scene.
INCREASED MORTALITY ASSOCIATED WITH EMS TRANSPORT OF GUNSHOT WOUND VICTIMS WHEN COMPARED TO PRIVATE VEHICLE TRANSPORT
Zafar, S.N., et al, Injury 45(9):1320, September 2014
BACKGROUND: There’s ongoing debate regarding the “stay and stabilize” approach for trauma patients. Several studies have questioned the value of various prehospital procedures for this population, citing delays to hospital arrival.
METHODS: This study from Johns Hopkins compared in-hospital mortality in patients aged 16+ with GSWs who were transported to level 1 or 2 trauma centers in the US by EMS or private vehicle and were included in the National Trauma Databank in 2007–2010. Only those transported to centers that managed at least 50 GSWs each year were included.
RESULTS: Of 74,187 patients transported to 182 trauma centers, 76% were transported by EMS (55,773) and 12.6% were transported by private vehicle (9,290). The remainder were transported by other means. Among the individual trauma centers, rates of transport by EMS varied from 0% to 100% (median 78%) and rates of transport by private vehicle varied from 0% to 92% (median 11%). The crude in-hospital mortality rate was 9.7% in the EMS group compared with 2.1% in the private vehicle group (p<0.001). After controlling for potential confounders, including patient demographic and injury characteristics, year of admission and trauma center level, the likelihood of in-patient death was increased two-fold among patients transported by EMS (odds ratio 2.0, 95% CI 1.73-2.35).
CONCLUSIONS: The authors acknowledge the methodologic limitations of their analysis, but note that these findings are consistent with a significant survival advantage of transport of GSW patients by private vehicle rather than EMS.
31 references (email@example.com – no reprints) Copyright 2015 by Emergency Medical Abstracts – All Rights Reserved 1/15 – #29
Penetrating trauma that threatens exsanguinating hemorrhage has only one true solution – timely surgical intervention. For incompressible, intracavitary bleeding there’s little that EMS can offer and opportunities to make matters worse. We know that permissive hypotension is likely better than massive infusions of crystalloid, that MAST trousers make things worse, and we suspect that airway interventions if done on scene probably are not important if there is no blood circulating. We know this from a variety of civilian and military studies that have opened our eyes to some of our misguided efforts. In the business, most of us feel that these are events best “treated with diesel”, i.e. rapid transport. In these cases, transport to trauma center will certainly demonstrate a time-dependent mortality curve and the fastest means of transport in areas with very short transport times will likely have better outcomes. On the other hand, we also are now very focused on the critical lifesaving importance of controlling extremity bleeding with tourniquets and packing and are extending this to civilian training as well. This has support from many quarters, again starting in the war experience in the Middle East but also demonstrated in the heroic acts of civilian bystander rescuers at the Boston Marathon who applied makeshift tourniquets to the injured. This “value-added” lifesaving intervention should be provided by all EMS services, ALS or BLS and will save lives in those cases compared to civilian transport if no bleeding control is exercised.
3. Bukata: But what about cardiac arrests? Certainly this must be a setting where the most trained and equipped individuals will excel. Not according to the next study. They found that outcomes were better with BLS care vs ALS care.
OUTCOMES AFTER OUT-OF-HOSPITAL CARDIAC ARREST TREATED BY BASIC VS. ADVANCED LIFE SUPPORT
Sanghavi, P., et al, JAMA Intern Med 175(2):196, February 2015
BACKGROUND: In the USA, most patients experiencing out-of-hospital cardiac arrests receive prehospital treatment by personnel with Advanced Life Support (ALS) training, but there are only limited data that support the use of ALS vs. Basic Life Support (BLS) personnel for this purpose.
METHODS: The authors, from Harvard University, performed an observational cohort study to compare the effects of ALS and BLS prehospital care in out-of-hospital cardiac arrest patients. Data were evaluated in a nationally representative sample of patients for whom ALS (31,292) or BLS (1,643) ambulance services were billed to Medicare in 2009-2011.
RESULTS: After adjustment for propensity scores, rates of survival to discharge and 90 days were higher among patients receiving BLS care than among those receiving ALS care (13.1% vs. 9.2% at discharge; 8.0% vs. 5.4% at 90 days). Much of this difference was related to higher early mortality in patients receiving ALS care. The ALS group was also more likely than the BLS group to have poor neurologic outcomes among the subgroup surviving to hospital admission (44.8% vs. 21.8%). Mean medical spending was greater in the BLS than in the ALS group ($11,875 vs. $9,097), partly because of the longer survival in the former group. Incremental medical spending per additional one-year survival in the BLS group relative to the ALS group was $154,333, which was less than the $206,775 mean medical spending amount per one-year survivor in the ALS group.
CONCLUSIONS: In this large study, BLS care for prehospital cardiac arrest appeared to be associated with better outcomes than ALS care.
33 references (firstname.lastname@example.org – no reprints) Copyright 2015 by Emergency Medical Abstracts – All Rights Reserved 7/15 – #7
The outcomes from out of hospital cardiac arrest on an ALS and BLS level is an interesting and challenging topic. Unfortunately, the article referred to in Dr Bukata’s article does not represent a particularly informative approach to understanding this issue, the article in JAMA and a subsequent larger version published in Annals of Internal Medicine have been reviewed in this journal in the past. These articles have merit insofar as they encourage us to examine whether our suppositions of the provision of care in cardiac arrest are valid and this is a good exercise. Unfortunately using retrospective billing data (as was the method in these studies) to do so has many limitations. In general, however, one must consider that studying out of hospital cardiac arrest is challenging and so studies require intense scrutiny for unintentional bias. The best outcomes in cardiac arrest are indeed likely to be those in which the level of provider doesn’t matter as much as the timely administration of defibrillation in a witnessed arrest. Cardiac arrest studies always involve a large number of patients who under no circumstances would be predicted to have a good outcome and they are the ones upon whom ALS is particularly focused. It is the ALS expertise and quite possibly not the medications that we hope improve the chances for survival.
4. Bukata: Even something as intuitive as endotracheal intubation being superior to bag-valve-mask ventilation in children has been unequivocally disproved – and this study is 16 years old.
EFFECT OF OUT-OF-HOSPITAL PEDIATRIC ENDOTRACHEAL INTUBATION ON SURVIVAL AND NEUROLOGIC OUTCOME: A CONTROLLED CLINICAL TRIAL
Gausche, M., et al, JAMA 283(6):783, February 9, 2000
METHODS: In this extraordinary controlled clinical trial, from Harbor-UCLA Medical Center in Torrance, CA, outcomes were compared in 410 children below the age of twelve who received bag-valve-mask (BVM) ventilatory support in the prehospital setting and 420 similar children who were assigned to receive endotracheal intubation (ETI). Indications for airway management included traumatic or nontraumatic cardiopulmonary or respiratory arrest, respiratory failure, airway obstruction, head trauma with nonpurposeful response, or a perceived need for assisted ventilation. All participating paramedics underwent an initial six-hour training course in pediatric airway management.
RESULTS: Rates of survival to hospital discharge were similar in the ETI and BVM groups (26% and 30%, respectively), as were rates of discharge with good neurologic outcome (20% and 23%). Survival and/or good neurologic outcome were statistically more likely in the BVM group in subgroups having diagnoses of child abuse, respiratory arrest and foreign body aspiration. Overall, ETI was successful in 57% of children in whom it was attempted. Complications specific to ETI included esophageal intubation (2%), recognized or unrecognized dislodgment of the ET tube (14%), mainstem bronchus intubation (18%), and incorrect tube size (24%). Median scene time and total prehospital time were longer (by 2-3 minutes) in the ETI group.
BACKGROUND: Although pediatric endotracheal intubation is taught in 97% of paramedic training programs and is widely used in the out-of-hospital setting, findings in this landmark study suggest that (in an urban environment) it is no better than, and may be worse than, pre-hospital use of BVM only.
29 references. Copyright 2000 by Emergency Medical Abstracts – All Rights Reserved 6/00 – #4
Airways and EMS are another controversial issue and one that we need to better understand. Dr Gausche’s article is considered one of the landmark articles in the EMS literature and deservedly so. It has compelled us to consider how and IF we should provide airway interventions in the pediatric population. It is important to realize nonetheless that this blockbuster study relied on taking a very large group of medics who were naïve to intubation and were trained in a very short course and then turned loose on pediatric intubations. Controls were in place and training occurred so certainly this was not a reckless practice in terms of the usual standards of care but nonetheless may not be as informative for systems that had been providing pediatric intubation for many years with appropriate quality improvement and outcome review. Nonetheless we should always consider whether “something” is always better than “nothing” if that something can in fact cause harm.
Bukata: Prehospital care should be required to withstand the searchlight of scientific inquiry just like the rest of medicine. The literature is loaded with studies that clearly challenge much of the status quo in EMS. Bottom line — there is solid evidence to support some serious experimenting with the provision of prehospital care. Perhaps more EMT units in urban areas and fewer paramedics (or a two-tiered system) could result in better outcomes as well as a lot of other changes. But we’ll never know until leaders have the courage to challenge many of our long-held assumptions.
Levy: The House of EMS is embracing practice based upon evidence. The EMS Evidence Based Guidelines project is an example of a forward thinking approach to making this practice of medicine conform with pathways that all of medicine is trying to define. Studies that compare ALS and BLS care in current studies is mostly defined solely by the presence of absence of a procedure or drug. It would be very difficult to design an RCT that effectively studied the intellectual domains in each group in respect to their approaches to a clinical event yet that is immensely important. Some of the most critical and mature decisions made by ALS providers are the decisions to do no interventions based upon their clinical insights. These very high level ALS decisions lead then to patients who appear to be “BLS”. While so much remains in the air, the most important thing we can do to assure high quality EMS care, BLS or ALS, is to demand that all EMS systems embrace rigorous quality improvement based upon practice supported by the best evidence put in the context of the specifics of the given system and provider mix. The procedures and drugs are all arrows in the quiver but the archer is the ALS provider.