REVIEWResuscitation and transfusion principles for traumatic hemorrhagic shock
Introduction
Traumatic injury is the leading cause of death for patients between the ages of 1 and 40,1 and approximately 90,000 people die per year in the US from traumatic injuries.2 US military reports estimate that 15–20% of traumatic deaths are potentially preventable and 66–80% of these deaths occur from hemorrhage.[3], 4 Rural civilian data indicate that approximately 10% of traumatic deaths are preventable,[5], [6] and 16% of preventable deaths are due to hemorrhage.7 If 10–20% of 90,000 US civilian traumatic deaths are preventable and 16–80% of these preventable deaths are due to uncontrolled bleeding this translates to between 1400 and 14,000 potentially preventable hemorrhagic trauma deaths per year in the US. Hemorrhagic deaths typically occur very early, usually within the first 6 h of admission.[8], [9], [10], [11] Early hypoperfusion or shock has been demonstrated to promote coagulopathy.[12], [13] Approximately 25% of patients with severe traumatic injury are coagulopathic upon admission.[14], [15] Shock and coagulopathy upon admission have been both independently associated with massive transfusion and increased mortality.[16], [17], [18], [19] Therefore, early identification of patients who are at risk of developing shock and coagulopathy, and subsequent strategies to prevent and control these processes may improve survival.[13], [16], [17], [20], [21]
The transfusion approach to hemorrhage has continually changed since the early 1900s. This evolution has included fresh whole blood and modified whole blood to the current virtually exclusive use of component therapy and crystalloid with whole blood being reserved for uncommon indications.[22], [23], 24, [25] After the development of whole blood fractionation, component therapy now predominates as the primary transfusion approach secondary to concerns for resource utilization and safety.[25], [26], 27 This change occurred without evidence documenting equivalent clinical outcome data between whole blood and component therapy.[25], [26], 27 In addition, regulatory approval of new storage solutions is based on RBC membrane viability and ATP concentrations instead of the ability of RBCs to deliver oxygen to the microvasculature or adverse effects on inflammation or immune function with stored RBCs.28 Current transfusion guidelines regarding indications for blood components were based upon expert opinion, experiments in euvolemic patients requiring elective surgery and data from the modified whole blood era which is no longer commonly available.[25], [26], 27 With new storage solutions, the age of transfused RBCs has progressively increased over time to a current limit of 42 days, without prospective studies evaluating the clinical effect of increased RBC storage length on critically ill patients.[22], [28]
Prompted by new data from combat casualties, an evolution of opinion is occurring in the trauma and transfusion medicine communities regarding the optimal resuscitative approach to hemorrhagic shock.27, [29], [30] Damage control resuscitation (DCR) is the overall guiding concept to emerge from the recent military experience.[29], [30], [31], [32] DCR which includes permissive hypotension as first described by Cannon in 1918 can be summarized as allowing the blood pressure to be slightly less than normal to promote thrombus formation while still providing enough perfusion to end organs.33 In other words, the goal of permissive hypotension is to prevent increasing the blood pressure to a threshold where a forming thrombus will not be able to achieve hemostasis, and re-bleeding occurs. This has been called “popping the clot”.34 This concept is practiced prior to surgical control. The practice and literature supporting permissive hypotension have been well documented and will not be discussed further.[32], [33], [34], [35], [36] DCR also advocates for the rapid control of surgical bleeding, prevention of acidosis, hypocalcemia and hypothermia, and for the limitation of excessive crystalloid use to decrease hemodilution. All of these principles are intended to prevent inducing or exacerbating a hypocoagulable state in these patients with severe traumatic injury who are at high risk of developing severe shock and coagulopathy. Hemostatic resuscitation is also a component of DCR and is a term to describe a unified transfusion approach to severe hemorrhagic shock.[31], [37], 38 Hemostatic resuscitation advocates for the transfusion of RBCs, plasma, and platelets in a 1:1:1 ratio and for the use of thawed plasma to achieve this ratio upon admission. This approach is also intended to minimize exacerbating a dilutional coagulopathy by replacing lost blood with plasma and platelet-containing products instead of early and large amounts of crystalloids and RBCs. Hemostatic resuscitation is also theoretically intended to address the consumptive coagulopathy and perhaps improve endothelial function which is currently being evaluated in multiple in vitro experiments. Adjuncts to hemostatic resuscitation include the appropriate use of coagulation factor and fibrinogen-containing products.[39], [40], 41, 42, 43 Fresh whole blood is also part of DCR in locations where it is available. Additional concepts that can be considered as a part of DCR include the preference for fresh RBCs,[19], [44], 45, [46], [47] and the potential use of thromboelastography to fine tune empiric blood product transfusion ratios and to direct the administration of coagulation factor products, and anti-fibrinolytics.24, [48]
The literature supporting these changes advocated by DCR has been met with appropriate caution and skepticism.49 A proposed change of practice should always be done carefully and thoughtfully and in a data-driven fashion, it is important to recognize that the literature supporting the current ATLS standard for the past 25 years was based upon 18 patients.50
While most of the literature reviewed is in patients with traumatic injury, further study is appropriate in different patient populations, such as those massively bleeding from ruptured aortic aneurysms,51 gastrointestinal or obstetric sources to determine if DCR concepts apply in these circumstances.
Section snippets
Traumatic coagulopathy and acute coagulopathy of trauma-shock
Traumatic coagulopathy is a hypocoagulable state that occurs in the most severely injured.[14], [15], 52, [53] There are multiple factors that may contribute to this coagulopathy, which evolve over time. Immediately after injury, hypoperfusion may cause coagulopathy as a result of increased anti-coagulation and hyperfibrinolysis via increased activated protein C production, tissue plasminogen activator and a concomitant decrease in plasminogen activator inhibitor concentrations and thrombin
DCR concepts and tools
Damage control resuscitation and hemostatic resuscitation are concepts that have been recently developed to describe what is currently thought by many to be the optimal resuscitative and transfusion approach to patients with hemorrhagic shock and immediately life-threatening injuries.[29], [30], [31], [32] Similar to damage control surgery the goal of damage control resuscitation is to “stay out of trouble instead of getting out of trouble”. Therefore in patients with severe traumatic injury
Alkaline and calcium therapy
While it appears to be important to prevent acidosis and hypocalcemia there is no evidence to support that the reversal of acidosis and hypocalcemia improve outcomes. In fact there are some studies that indicate when acidosis is treated coagulopathy is not reversed.121 While these practices are controversial and definitive studies have not been performed it is not unusual for alkaline solutions such as sodium bicarbonate or THAM (tromethamine) to be given to reverse acidosis and calcium
Massive transfusion protocols
A recent survey has been reported on the use of massive transfusion protocols (MTPs) world-wide in adult patients.24 In this survey it is self-reported that 45% of respondents use a MTP, 19% use one sporadically, and 34% do not. The development of a massive transfusion protocol for patients with severe life-threatening bleeding is important to standardize the approach to these patients and to provide structure and organization to what is usually a chaotic situation.125 Important aspects of a
Conclusion
Trauma is the most common cause of death for patients 1–40 years of age, death from hemorrhagic shock is the most common cause of preventable death within 6 h of admission, and the rapid identification and treatment of coagulopathy may improve survival. Therefore, it is imperative that we understand the pathophysiology of traumatic coagulopathy and ACoTS better, and develop methods to decrease death from hemorrhage. We must also continue to develop research protocols to determine the optimal
Conflict of interest statement
No conflict of interest.
References (127)
- et al.
Trauma fatalities: time and location of hospital deaths
J Am Coll Surg
(2004) - et al.
Early predictors of massive transfusion in combat casualties
J Am Coll Surg
(2007) - et al.
Are we giving enough coagulation factors during major trauma resuscitation?
Am J Surg
(2005) - et al.
Effect of fibrinogen on reversal of dilutional coagulopathy: a porcine model
Br J Anaesth
(2005) - et al.
Age of transfused blood is an independent risk factor for postinjury multiple organ failure
Am J Surg
(1999) - et al.
Thromboelastography and recombinant factor VIIa-hemophilia and beyond
Semin Hematol
(2004) - et al.
Anemia, allogenic blood transfusion, and immunomodulation in the critically ill
Chest
(2005) - et al.
New developments in fluid resuscitation
Surg Clin North Am
(2007) - CDC. Deaths: final data for 2004. US Department of Health and Human Services, CDC, National Center for Health...
- Trauma facts. <http://www.aast.org/TraumaFacts/dynamic.aspx?id=964>; 2008...
The causes of death in conventional land warfare: implications for combat casualty care research
Mil Med
Causes of death in special operations forces on the modern battlefield: 2001–2006
Ann Surg
Analysis of preventable trauma deaths and inappropriate trauma care in a rural state
J Trauma
Effect of a voluntary trauma system on preventable death and inappropriate care in a rural state
J Trauma
Preventable deaths from hemorrhage at a level I Canadian trauma center
J Trauma
Massive transfusion in trauma patients: tissue hemoglobin oxygen saturation predicts poor outcome
J Trauma
Epidemiology of immediate and early trauma deaths at an urban level I trauma center
Am Surg
Epidemiology of trauma deaths: a reassessment
J Trauma
The coagulopathy of trauma: a review of mechanisms
J Trauma
Acute coagulopathy of trauma: hypoperfusion induces systemic anticoagulation and hyperfibrinolysis
J Trauma
Acute traumatic coagulopathy
J Trauma
Early coagulopathy predicts mortality in trauma
J Trauma
A predictive model for massive transfusion in combat casualty patients
J Trauma
Effect of plasma and red blood cell transfusions on survival in patients with combat related traumatic injuries
J Trauma
Warm fresh whole blood is independently associated with improved survival for patients with combat-related traumatic injuries
J Trauma
Increased mortality associated with the early coagulopathy of trauma in combat casualties
J Trauma
Giving plasma at a 1:1 ratio with red cells in resuscitation: who might benefit?
Transfusion
Blood use in war and disaster: lessons from the past century
Transfusion
Blood
Management of coagulopathy in the patients with multiple injuries: results from an international survey of clinical practice
J Trauma
The use of fresh whole blood in massive transfusion
J Trauma
Hemostatic resuscitation
Current issues relating to the transfusion of stored red blood cells
Vox Sang
Damage control resuscitation: the need for specific blood products to treat the coagulopathy of trauma
Transfusion
Damage control resuscitation: directly addressing the early coagulopathy of trauma
J Trauma
Damage control resuscitation: a sensible approach to the exsanguinating surgical patient
Crit Care Med
Fluid resuscitation in modern combat casualty care: lessons learned from Somalia
J Trauma
The preventive treatment of wound shock
JAMA
Blood pressure at which rebleeding occurs after resuscitation in swine with aortic injury
J Trauma
Immediate versus delayed fluid resuscitation for hypotensive patients with penetrating torso injuries
N Engl J Med
Preparation of battle casualties for surgery
Ann Surg
Optimizing outcomes in damage control resuscitation: identifying blood product ratios associated with improved survival
J Trauma
Review of current blood transfusions strategies in a mature level I trauma center: were we wrong for the last 60 years?
J Trauma
The effect of fibrinogen substitution on reversal of dilutional coagulopathy: an in vitro model
Anesth Analg
The ratio of fibrinogen to red cells transfused affects survival in casualties receiving massive transfusions at an army combat support hospital
J Trauma
Recombinant factor VIIa as adjunctive therapy for bleeding control in severely injured trauma patients: two parallel randomized, placebo-controlled, double-blind clinical trials
J Trauma
The effect of recombinant activated factor VII on mortality in combat-related casualties with severe trauma and massive transfusion
J Trauma
The risks associated with fresh whole blood and RBC transfusions in a combat support hospital
Crit Care Med
Age of transfused blood: an independent predictor of mortality despite universal leukoreduction
J Trauma
Increased risk of DVT and mortality with the transfusion of older RBCs for patients with traumatic injuries
Crit Care Med
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