Damage control resuscitation: An evidence-based report

Timing of intervention

More than 60,000 civilian deaths due to hemorrhagic shock occur in the United States each year. It is estimated that worldwide, there are 1.5 million deaths annually due to hemorrhage as a result of trauma, and traumatic injury is the leading cause of death in people between the age of 1 and 44 years old. Importantly, because hemorrhagic shock from trauma disproportionately affects young people, nearly 75 million years of life are lost on a global level. Approximately half of these deaths occur in the prehospital setting and achieving timely bleeding control is a challenge faced in all trauma systems. The potential importance of moving the pendulum of hemorrhage control closer to the time of injury is apparent.

Unlike blood, time, once spent, is impossible to recover and cannot be replaced. More than any other modifiable risk factor, time may be the most vital factor when it comes to reducing preventable hemorrhage mortality after traumatic injury. As early as 1975, R. Adams Cowley observed that patients who experienced a delay in treatment suffered higher mortality. He subsequently coined the term “golden hour.” While the concept of the “golden hour” highlights the importance of early treatment, we now recognize that mortality from severe hemorrhage can occur in the first 20 to 35 minutes. Evaluating over 42,000 patients with torso injuries from the National Trauma Data Base, Alarhayem et al showed that mortality after severe truncal hemorrhage increased significantly with longer prehospital times. Furthermore, the risk of death was greatest within the first 30 minutes. The median transport time observed in their study was 37 minutes. Put directly, the risk of death was greatest before the patient ever reached the hospital.

For the last 40 years, civilian emergency medical services (EMS) practice has been to “scoop and run” as opposed to “stay and play.” The existing paradigm is that the patient will receive definitive care at the hospital, and any delays that may arise as a result of prehospital care should be avoided. This practice has served its purpose for a large number of patients. Unfortunately, those that arrive to the hospital alive represent only the tip of the iceberg with a median hemorrhage control time of 2 hours from the time of injury to the time of surgical hemorrhage control ( Fig. 1 ). Special consideration is needed for the large proportion of patients who die as a result of hemorrhage prior to arrival. It is notable to consider that the in-hospital mortality for hypotensive patients in need of MTP (47%) has not changed in over last 12 years. These findings are indicative of a need for intervention at an earlier phase of care.

Intubation vs. circulation

Fitting with the traditional airway, breathing, circulation (ABC) approach to emergency management, intubation is one of the most common prehospital procedures in the trauma population. It has been shown, however, that prehospital intubation of penetrating trauma patients does not demonstrate a survival benefit. Furthermore, for patients who survived to admission, prehospital intubation was associated with increased mortality and was not protective against a variety of in-hospital complications. Intubation in the setting of animal models of severe hemorrhagic shock has perhaps provided a look at the specific potential harms of prehospital intubation, specifically prior to volume resuscitation. Taghavi et al demonstrated that when compared with bag-valve-mask ventilation, intubation was associated with more profuse hemorrhage, worsened hypothermia, and higher lactate, raising the question of the benefits of intubation prior to effective volume resuscitation. This relationship between airway vs. circulation in the management of patients with severe hemorrhage has been an area of increased focus lately.

The ABC approach to trauma care “became the standard of care despite lack of scientific evidence.” In one study, Ferrada et al challenged the ABC paradigm, proposing, instead, that circulation should be the initial point of focus when treating a trauma patient (CAB approach). Looking at 245 patients who received intravenous blood product resuscitation prior to intubation (CAB) and 195 patients who were intubated prior to receiving volume resuscitation (ABC), Ferrada et al showed there was no statistically significant difference in mortality between the two groups. The group notes that this study highlights that many trauma centers are already initiating volume resuscitation prior to intubation. They further conclude that because of the noninferior mortality outcome of the CAB approach vs. the ABC approach, further prospective investigation is warranted. Studies are currently underway looking at exactly this phenomenon.

Fluid resuscitation vs. restriction

Fluid resuscitation is perhaps one of the most contentious points in the prehospital care debate. Current civilian EMS guidelines regarding prehospital fluid resuscitation are not consistently established. If there is a common traditional theme, it is that for systolic blood pressures less than 90 mm Hg, rapid bolus administration of normal saline or Ringer’s lactate should be initiated. Upon closer examination, however, the use of crystalloid solution may actually do more harm than good. Elevated blood pressure can potentially displace clots in patients with uncontrolled hemorrhage; the absence of clotting activity in crystalloid solutions can result in dilutional coagulopathy; and finally, the high chloride content of crystalloid solution may exacerbate the acidosis seen in shock.

A large-scale review from 2009 asked, among other questions, “If prehospital vascular access is obtained, should intravenous fluids be given?” The consensus reached was that no “convincingly justifiable recommendation based on available data” could be made. The study did, however, come to the conclusion that a “reasonably justifiable recommendation” could be made to withhold intravenous fluids in the prehospital setting for patients with penetrating torso injuries, strategies supported by the historical permissive hypotension study from Bickell.

Prehospital tourniquet use

Tourniquet use to control hemorrhage after extremity trauma has been described for hundreds of years, though it fell out of favor for much of the 20th century due to concerns about prolonged tourniquet times leading to iatrogenic injuries including limb ischemia and amputations. However, the conflicts in Iraq and Afghanistan in the early 21st century provided an opportunity for resurgence of battlefield tourniquet use with good results, including several studies in 2008 and 2009 that demonstrated that tourniquets effectively controlled hemorrhage and improved mortality without increasing complications. Renewed interest in civilian tourniquet use shortly after has continued over the past decade with increasing tourniquet use by EMS and police forces in the United States as well as recommendations by the Hartford Consensus in 2013 that tourniquets be utilized by first responders and even laypersons in a mass casualty event, culminating in the rollout of the American College of Surgeons’ Stop the Bleed program in 2017 to teach hemorrhage control techniques including tourniquet application on a broad scale to the public.

Several recent studies have been conducted attempting to evaluate tourniquet use in civilian populations; however, most of these studies have been limited to retrospective database reviews. Most of the initial studies attempted to describe tourniquet efficacy and safety in civilian populations. In 2015 and 2016, several small retrospective reviews by Zietlow et al, Kue et al, Leonard et al, and Inaba et al evaluated the emerging tourniquet use, finding the tourniquets effectively controlled extremity hemorrhage in 89%–98% of patients. These early studies also attempted to describe amputation and other complication rates and generally describe low rates of complications attributable to tourniquet use. Scerbo and colleagues conducted a retrospective review of 105 patients with prehospital tourniquets at a Level I trauma center between 2008 and 2013 and felt that 90% had appropriate indications for placement; they found that this group had a higher amputation rate (32% vs. 0%, p = 0.03) and nerve palsy rate (5% vs. 0%, p = 0.57) than the nonindicated group, concluding that tourniquets were safe and generally appropriately applied in civilians. The largest study from 2015 was a multi-institutional retrospective review by Schouroll and colleagues, which included 197 patients with prehospital tourniquets presenting to 9 Level I trauma centers between 2010 and 2013. They redemonstrated a high efficacy rate of hemorrhage control at 89%, a nerve palsy rate of 6.1%, and amputation rate of 18%, none of which was felt to be directly attributable to tourniquet use. However, the patients were found to be less severely injured than those described in previous military studies, with lower amputation rates and mortality rates, so concern persisted about whether military data could be extrapolated to civilian populations.

More recent studies have attempted to compare tourniquet use to nonuse and determine the effect on outcomes. A second study by Scerbo et al in 2017 compared patients with prehospital tourniquets to those with tourniquets placed at the trauma center and found that prehospital tourniquet use was associated with increased systolic blood pressure at arrival to the hospital (125 vs. 101 mm Hg, p < .001), decreased incidence of blood transfusion (34% vs. 55%, p = 0.02), and decreased mortality from hemorrhagic shock (3% vs. 14%, p = 0.01). The following year, the multicenter “Texas Tourniquet Study” compared prehospital tourniquet use vs. nonuse in 1026 patients with peripheral vascular injury at 11 trauma centers from 2011 to 2016; they found that 181 patients (17.6%) had prehospital tourniquet placement; there was no crude mortality difference (3.9% vs. 5.2%, odds ratio [OR] 1.35, p = 0.452). However, on multivariate analysis prehospital tourniquet use was independently associated with survival (adjusted OR 5.86; 95% confidence interval [CI] 1.41–24.47, adjusted p = 0.015) with similar delayed amputation rates between the two groups (1.1% vs. 1.1%, adjusted OR 1.82, 95% CI 0.36–9.99; adjusted p = 0.473). And finally, a retrospective review by Smith and colleagues of 204 patients with prehospital tourniquets matched to 127 without found prehospital tourniquets were associated with higher systolic blood pressure on arrival to the trauma center (120 vs. 112 mm Hg, p = 0.003), fewer PRBC blood and fresh frozen plasma (FFP) transfusions (2.0 vs. 9.3, p < 0.001) and (1.4 vs. 6.2, p < .001), and lower amputation rates (0.8% vs. 9.1%, p = 0.005).

The previously discussed studies suggest that prehospital tourniquet use in civilian populations is generally safe, effective, and associated with decreased shock, blood transfusion needs, and mortality, and prehospital tourniquet use has been widely adopted as an essential component of DCR for civilians with extremity hemorrhage. However, all studies so far have been Level 3 data consisting of retrospective reviews of registry data; higher-quality studies including prospective data collection are necessary to improve our understanding of civilian prehospital tourniquet use.