Circulation First for Rapidly Bleeding Trauma Patients: Time to Change the Paradigm?

The Advanced Trauma Life Support (ATLS) and its iconic Airway–Breathing–Circulation (ABC) algorithm have long been a gold standard in trauma resuscitation—a cornerstone for training many generations of surgeons, ER physicians and others who care for the injured patient. This “one good way,” by virtue of repetition and standardization, has helped ensure major injuries are not missed, nor lifesaving steps delayed, especially in the hands of nonexperts.¹ Many lives around the world have been saved by this program, and many, including the authors, are honored to teach ATLS, which is one of the most important contributions to trauma care and education that have been developed in the past century.

The ABC algorithm has the benefit of being straightforward (and alphabetical!), thus easy to memorize and recall in a stressful, unfamiliar situation. It is the starting block for how surgery residents in the United States are taught to manage trauma resuscitations, and adhering to fundamental ATLS principles is expected of newly minted surgeons fielding trauma questions in the qualifying and certifying examinations of the American Board of Surgery.

Over the years, ATLS has morphed from its original construct of describing initial care of the injured patient at a small, often rural facility, to becoming the default for trauma resuscitation in multiple settings. Thus, the potential for rigid adherence to a linear algorithm has grown along with the increasing popularity and widespread acceptance of this teaching. Situations may arise in which physicians today implement these teachings somewhat dogmatically in patient care settings, even when clinical findings suggest a better option. While clearly not the intent of ATLS authors past or present, this is an almost inevitable by-product of any attempt at simplifying the teaching of a very complex clinical scenario.

Over the years, there has been discussion of the alternate, CAB (compressions–airway–breaths)—or circulation-first approach—to replace the traditional ABC.² This approach prioritizes circulation, implying that control of bleeding and replacement of lost blood is placed ahead of airway and breathing in the order of priority. Since most preventable early deaths from trauma occur from hemorrhage, this has the obvious logical benefit of addressing the most commonly lethal problem first. In military settings around the world, it has been recognized for some time that the cause of death will likely be catastrophic hemorrhage.³ This recognition has led to the formal incorporation of CAB into the Battlefield Advanced Trauma Life Support BATLS algorithm that is used by the military in the United Kingdom.⁴

In Level 1 trauma centers, it is well recognized that trauma is the ultimate team sport: Multiple individuals address multiple facets of injury care, damage control and resuscitation simultaneously. While a linear algorithm helps reduce variability and the chances of missing a key step, it is an artificial oversimplification of what actually needs to occur in a patient with multiple severe injuries. Whether the algorithm is ABC or CAB, there will always be a pitfall if one aspect is emphasized at the expense of the others. However, given that significantly fewer early deaths result from airway injuries versus bleeding, placing circulation first is likely to reduce the chances of a potentially lethal error from following a linear algorithm. Ideally, every trauma activation would include an expert at bedside who could quickly assess the patient, using heuristic patterns built on a strong foundation of cognitive knowledge honed by years of experience, to identify the most immediate concerns and address these in a logical order of priority. Unfortunately, such an approach cannot be taught to a novice in a two-day course; there will always be something lost by reducing the art of what we do to a formulaic process. The question then becomes: Is our current distillation the least harmful choice?

In a CAB approach, the multiple factors that inform intravascular volume would be evaluated early. This assessment would include heart rate and blood pressure, either as stand-alone markers or incorporated into scoring systems, such as the Shock Index⁵ or ABC score.⁶ It would also include a quick assessment for potential sources of bleeding. This evaluation includes external sources such as lacerations and wounds, as well as internal sources within the chest, abdomen, pelvis or extremities; a chest and pelvis radiograph and FAST exam would thus be considered components of the circulatory assessment. Simultaneously, obtaining intravenous access and starting resuscitation with blood—ideally, whole blood—in patients who already have evidence of significant bleeding, would be performed.

There are several reasons why an airway-first approach may actually be detrimental to the injured patient, beyond simply delaying more useful interventions. The vasodilatory response that occurs immediately after anesthetic drugs are administered for intubation frequently results in hypotension. When a patient is already volume-depleted from hemorrhagic shock, this hypotension may even precipitate cardiac arrest, as every experienced trauma surgeon has learned the hard way at one point or another. Positive pressure ventilation further impedes venous return and is particularly detrimental at higher respiratory rates⁸; thus, multiple factors contribute to a downward spiral, from which many patients do not recover. Shafi et al published an analysis of the National Trauma Data Bank showing that prehospital intubations resulted in exacerbating hypotension in hypovolemic patients, as would be expected from basic physiologic principles.⁹ A 2019 meta-analysis by Ferrada et al confirms significantly higher mortality in patients who suffer post-intubation hypotension.¹⁰ Intubating before correcting hypotension may not help, and can hurt, the patients we are working so hard to save.

A classic example of this scenario is a patient who is brought in after a vehicular collision and is found to be hypotensive with reduced mental alertness. This scenario is common in real life, as it is in ATLS simulations, and in high-stakes examinations directed at surgeons and ER physicians. Securing a safe airway and starting resuscitation for shock are both vital to this patient’s survival; and at a high-level trauma center, one would expect these measures to be addressed simultaneously. However, in current ATLS scenarios set in a one-physician rural setting, attending to the airway including intubation and mechanical ventilation is prioritized ahead of resuscitation. This order could worsen the patient’s hypotension and increase their instability, which is a scenario that the nonexpert is even less likely to be able to handle.

It is worth noting that a circulation-first approach has been adopted by the American Heart Association for immediate response to medical cardiac arrest since 2010, when its algorithm changed to CAB from ABC.¹¹ This change was based on a preponderance of data showing that prioritizing circulation was likely to save more lives, in cases of cardiovascular collapse. While trauma is clearly a very different etiology from cardiogenic causes of cardiorespiratory arrest, there is no reason to imagine that the basic principles of resuscitation would not hold true, even in trauma settings, for the vast majority of patients.

ATLS is by far the best-known approach to immediate resuscitation of injured patients in North America; it is also widely used worldwide. There is an opportunity to harmonize the way we teach algorithms to nonexperts, to more closely mimic what is actually done by experts—a comprehensive, multipronged approach that recognizes the lifesaving importance of starting resuscitation for bleeding early in the process. The ultimate question is not whether A or C should come first in every case; it is whether we can teach those people caring for trauma patients the ability to recognize what matters most in which situation, and to balance the pros and cons of early intubation with the risk for hypotension it engenders, and to navigate the safest course for a given patient.

VIDEO

Editorial board member Peter Kim, MD, interviews Drs. Dissanaike and Ferrada about this topic at generalsurgerynews.com/Multimedia

References

1. American College of Surgeons. Advanced trauma life support. Accessed November 11, 2022. https://www.facs.org/quality-programs/ trauma/ education/ advanced-trauma-life-support
2. Ferrada P. Am Surg. 2018;84(2):e75-e76.
3. Hodgetts TJ, Mahoney PF, Russell MQ, et al. Emerg Med J. 2006;23(10):745-746.
4. Hodgetts T, Mahoney P, Evans G, et al. Battlefield advanced trauma life support. 3rd ed. 2006. Defence Medical Education and Training Agency. Joint Service Publication; 570.
5. Allgower M, Burri C. Dtsch Med Wochenschr. 1967;92(43):1947-1950.
6. Nunez TC, Voskresensky IV, Dossett LA, et al. J Trauma. 2009;66(2):346-352.
7. Tran A, Yates J, Lau A, et al. J Trauma. 2018;84(5):802-808.
8. Pepe PE, Raedler C, Lurie KG, et al. J Trauma. 2003;54(6):1048–1055.
9. Ferrada P, Manzano-Nunez R, Lopez-Castilla V, et al. Am Surg. 2019;85(2):167-172.
10. Shafi S, Gentilello L. J Trauma. 2005;59(5):1140-1145.
11. Ferrada P, Callcut RA, Skarupa DJ, et al. AAST multi-institutional trials committee. World J Emerg Surg. 2018;13:8.

Dr. Dissanaike is the Peter C. Canizaro Chair and University Distinguished Professor of Surgery at Texas Tech University Health Sciences Center, in Lubbock. Dr. Ferrada is a professor of medical education at the University of Virginia, in Charlottesville, and the divisional and system chief of Trauma and Acute Care Surgery at Inova Healthcare System, in Falls Church, Va.

The authors reported no relevant financial disclosures.