Plasma supplementation is beneficial for coagulation during severe hemorrhagic shock

Large Animal Models for Simulating Physiology of Transfusion of Red Cell Concentrates-A Scoping Review of The Literature

Background and Objectives: Transfusion of red cell concentrates is a key component of medical therapy. To investigate the complex transfusion-associated biochemical and physiological processes as well as potential risks for human recipients, animal models are of particular importance. This scoping review summarizes existing large animal transfusion models for their ability to model the physiology associated with the storage of erythrocyte concentrates. Materials and Methods: The electronic databases PubMed, EMBASE, and Web of Science were systematically searched for original studies providing information on the intravenous application of erythrocyte concentrates in porcine, ovine, and canine animal models. Results: A total of 36 studies were included in the analysis. The majority of porcine studies evaluated hemorrhagic shock conditions. Pig models showed high physiological similarities with regard to red cell physiology during early storage. Ovine and canine studies were found to model typical aspects of human red cell storage at 42 days. Only four studies provided data on 24 h in vivo survival of red cells. Conclusions: While ovine and canine models can mimic typical human erythrocyte storage for up to 42 days, porcine models stand out for reliably simulating double-hit pathologies such as hemorrhagic shock. Large animal models remain an important area of translational research since they have an impact on testing new pharmacological or biophysical interventions to attenuate storage-related adverse effects and allow, in a controlled environment, to study background and interventions in dynamic and severe disease conditions.

Volume Resuscitation in the Acutely Hemorrhaging Patient: Historic Use to Current Applications

Acute hemorrhage in small animals results from traumatic and non-traumatic causes. This review seeks to describe current understanding of the resuscitation of the acutely hemorrhaging small animal (dog and cat) veterinary patient through evaluation of pre-clinical canine models of hemorrhage and resuscitation, clinical research in dogs and cats, and selected extrapolation from human medicine. The physiologic dose and response to whole blood loss in the canine patient is repeatable both in anesthetized and awake animals and is primarily characterized clinically by increased heart rate, decreased systolic blood pressure, and increased shock index and biochemically by increased lactate and lower base excess. Previously, initial resuscitation in these patients included immediate volume support with crystalloid and/or colloid, regardless of total volume, with a target to replace lost vascular volume and bring blood pressure back to normal. Newer research now supports prioritizing hemorrhage control in conjunction with judicious crystalloid administration followed by early consideration for administration of platelets, plasma and red blood during the resuscitation phase. This approach minimizes blood loss, ameliorates coagulopathy, restores oxygen delivery and correct changes in the glycocalyx. There are many hurdles in the application of this approach in clinical veterinary medicine including the speed with which the bleeding source is controlled and the rapid availability of blood component therapy. Recommendations regarding the clinical approach to volume resuscitation in the acutely hemorrhaging veterinary patient are made based on the canine pre-clinical, veterinary clinical and human literature reviewed.

Forgot calcium? Admission ionized-calcium in two civilian randomized controlled trials of prehospital plasma for traumatic hemorrhagic shock

BACKGROUND

Randomized clinical trials (RCTs) support the use of prehospital plasma in traumatic hemorrhagic shock, especially in long transports. The citrate added to plasma binds with calcium, yet most prehospital trauma protocols have no guidelines for calcium replacement. We reviewed the experience of two recent prehospital plasma RCTs regarding admission ionized-calcium (i-Ca) blood levels and its impact on survival. We hypothesized that prehospital plasma is associated with hypocalcemia, which in turn is associated with lower survival.

METHODS

We studied patients enrolled in two institutions participating in prehospital plasma RCTs (control, standard of care; experimental, plasma), with i-Ca collected before calcium supplementation. Adults with traumatic hemorrhagic shock (systolic blood pressure ≤70 mm Hg or 71-90 mm Hg + heart rate ≥108 bpm) were eligible. We use generalized linear mixed models with random intercepts and Cox proportional hazards models with robust standard errors to account for clustered data by institution. Hypocalcemia was defined as i-Ca of 1.0 mmol/L or less.

RESULTS

Of 160 subjects (76% men), 48% received prehospital plasma (median age, 40 years [interquartile range, 28-53 years]) and 71% suffered blunt trauma (median Injury Severity Score [ISS], 22 [interquartile range, 17-34]). Prehospital plasma and control patients were similar regarding age, sex, ISS, blunt mechanism, and brain injury. Prehospital plasma recipients had significantly higher rates of hypocalcemia compared with controls (53% vs. 36%; adjusted relative risk, 1.48; 95% confidence interval [CI], 1.03-2.12; p = 0.03). Severe hypocalcemia was significantly associated with decreased survival (adjusted hazard ratio, 1.07; 95% CI, 1.02-1.13; p = 0.01) and massive transfusion (adjusted relative risk, 2.70; 95% CI, 1.13-6.46; p = 0.03), after adjustment for confounders (randomization group, age, ISS, and shock index).

CONCLUSION

Prehospital plasma in civilian trauma is associated with hypocalcemia, which in turn predicts lower survival and massive transfusion. These data underscore the need for explicit calcium supplementation guidelines in prehospital hemotherapy.

LEVEL OF EVIDENCE

Therapeutic, level II.

Combat: Initial Experience with a Randomized Clinical Trial of Plasma-Based Resuscitation in the Field for Traumatic Hemorrhagic Shock

The existing evidence shows great promise for plasma as the first resuscitation fluid in both civilian and military trauma. We embarked on the Control of Major Bleeding After Trauma (COMBAT) trial with the support of the Department of Defense to determine if plasma-first resuscitation yields hemostatic and survival benefits. The methodology of the COMBAT study represents not only 3 years of development work but also the integration of nearly two decades of technical experience with the design and implementation of other clinical trials and studies. Herein, we describe the key features of the study design, critical personnel and infrastructural elements, and key innovations. We will also briefly outline the systems engineering challenges entailed by this study. The COMBAT trial is a randomized, placebo-controlled, semiblinded, prospective, phase IIB clinical trial conducted in a ground ambulance fleet based at a level I trauma center and part of a multicenter collaboration. The primary objective of the COMBAT trial is to determine the efficacy of field resuscitation with plasma first compared with standard of care (normal saline). To date, we have enrolled 30 subjects in the COMBAT study. The ability to achieve intervention with a hemostatic resuscitation agent in the closest possible temporal proximity to injury is critical and represents an opportunity to forestall the evolution of the "bloody vicious cycle." Thus, the COMBAT model for deploying plasma in first-response units should serve as a model for randomized clinical trials of other hemostatic resuscitative agents.

Different recovery profiles of coagulation factors, thrombin generation, and coagulation function after hemorrhagic shock in pigs

BACKGROUND

Hemorrhagic shock contributes to coagulopathy after trauma. We investigated daily changes of coagulation components and coagulation function for 5 days in hemorrhaged and resuscitated pigs.

METHODS

Fourteen pigs were randomized into the sham control (C) and the hemorrhage and lactated Ringer's resuscitation (H-LR) groups. On day 1, hemorrhage was induced in the H-LR group by bleeding 35% of the total blood volume, followed by LR resuscitation at three times the bled volume. Pigs in the C group were not hemorrhaged or resuscitated. Hemodynamics and coagulation were measured daily after H-LR on day 1 to day 5.

RESULTS

No changes in hemodynamics and coagulation function occurred in C. Hemorrhage decreased mean arterial pressure and increased heart rate. LR resuscitation corrected these changes within 2 hours. Compared with the baseline values (BL) on day 1, fibrinogen levels were decreased to 76% ± 6% by H-LR on day 1, increased to 217% ± 16% on day 2, and remained increased thereafter; platelet counts were decreased to 63% ± 5% by H-LR on day 1 and remained lower on days 2 and 3 but returned to BL by days 4 and 5 (all p < 0.05). Thrombin generation was decreased by H-LR on days 1 and 2 but then increased to above BL on days 4 and 5. Coagulation factor levels were decreased by H-LR on day 1 but returned to BL on day 3 except for factor XIII. Clot strength was decreased by H-LR on day 1 and returned to BL by day 2. Clot rapidity did not change on day 1 but was decreased on days 2 and 3 and returned to BL on days 4 and 5.

CONCLUSION

Hemorrhage and resuscitation reduced coagulation components and compromised coagulation function, which showed different recovery profiles over the 5-day study period.

Coagulopathy after traumatic brain injury

Traumatic brain injury has long been associated with abnormal coagulation parameters, but the exact mechanisms underlying this phenomenon are poorly understood. Coagulopathy after traumatic brain injury includes hypercoagulable and hypocoagulable states that can lead to secondary injury by either the induction of microthrombosis or the progression of hemorrhagic brain lesions. Multiple hypotheses have been proposed to explain this phenomenon, including the release of tissue factor, disseminated intravascular coagulation, hyperfibrinolysis, hypoperfusion with protein C activation, and platelet dysfunction. The diagnosis and management of these complex patients are difficult given the lack of understanding of the underlying mechanisms. The goal of this review is to summarize the current knowledge regarding the mechanisms of coagulopathy after blunt traumatic brain injury. The current and emerging diagnostic tools, radiological findings, treatment options, and prognosis are discussed.

Coagulation challenges after severe injury with hemorrhagic shock

During the past 50 years, there have been huge changes in the approach to coagulopathic bleeding following the treatment of traumatic hemorrhagic shock (HS). Treatment during the 1960s consisted primarily of physiologic saline (balanced electrolyte solution [BES]) and whole blood supported with sodium bicarbonate for acidosis. Subsequent coagulopathy was assumed to be caused by lack of the labile factors (FV and FVIII) which were then replaced by fresh whole blood. The decade of 1970s saw the implementation of component therapy by the American Blood Banking Association so that HS was treated with BES and packed red blood cells (RBC). A new paradigm had to be learned to determine when and how much fresh frozen plasma (FFP) was needed to restore all coagulation factors. By the end of 1970s, most trauma centers were supplementing BES and RBC with FFP in patients with severe injuries requiring massive transfusion of more than one circulating blood volume. By the 1980s, the use of FFP skyrocketed, creating a crisis for the American Blood Banking Association. This led to a National Institute of Health Consensus Development Conference which concluded that FFP should be given to only those patients who had a documented coagulopathy as evidenced by a prolongation of the prothrombin time and the partial thromboplastin time. Restriction of FFP replacement to patients with proven coagulopathy after treatment for HS led to postoperative bleeding which was sometimes fatal. During the 1990s, uncontrolled clinical studies and rigorously controlled animal studies showed that FFP should be administered before the onset of proven coagulopathy with prolongation of the prothrombin time and partial thromboplastin time. Later during the 1990s, recombinant-activated factor VII (FVIIa) was purported to provide quicker hemostasis in patients treated with HS. The efficacy of FVIIa supplementation is still being assessed. During the 2010s, the military surgeons promoted the use of a hemostatic regimen which consists of platelets, RBC, and FFP in a 1:1:1 ratio. This recommendation is still being assessed with different authors reporting benefits and detriments. Throughout these years, an unusual entity of disseminated intravascular coagulation (DIC) was known to complicate the resuscitation of seriously injured patients with HS. This syndrome was typically seen after treatment of HS and was associated with abnormal bleeding plus respiratory failure and renal failure thought to be caused by a combination of micro- and macrothromboses. The early studies suggested that the best therapy for breaking this viscous cycle of bleeding and intravascular coagulation was by infusing fresh whole blood. The theoretical benefits of administering heparin to prevent the thrombosis and epsilon-aminocaproic acid to enhance lysis have not proven beneficial. DIC is also seen in association with toxic exposures, including snake bites. Epsilon-aminocaproic acid may be beneficial in that setting. Many of the intricate understandings of DIC remain elusive and are still being studied.

Fresh frozen plasma/red blood cell resuscitation regimen that restores procoagulants without causing adult respiratory distress syndrome

BACKGROUND

Controversy exists about the ideal fresh frozen plasma/red blood cell (FFP/RBC) ratio for resuscitation of patients requiring massive transfusion (MT). This study correlates the FFP/RBC with clotting time (CT), prothrombin time (PT), partial thromboplastin time (PTT), and thrombin time (TT); with procoagulants (fibrinogen [FI], factor 5 [FV], and factor 8 [FVIII]); and with adult respiratory distress syndrome (pO2/FIO2).

METHODS

The 32 patients studied in operating room (OR) were in shock for 47 minutes and received an average of 17.6 units RBC, 4.2 units FFP, and 14.2 L balanced electrolyte solution. The 53 patients (including 22 of the OR patients), studied an average of 9.5 hours after operation, had an average shock time of 42 minutes, and received 17.4 units RBC, 4.6 units FFP, and 12.3 L balanced electrolyte solution in OR.

RESULTS

The FFP/RBC in OR averaged 0.3:1 (range: 0.1:1 to 0.9:1). The OR study, done after a minimum of 10 RBC units at 3.8 hours, showed a PT of 3.5 seconds off normal (international normalized ratio < 1.3), a PTT of 34 seconds, and TT of 7.9 seconds off normal. FI, FV, and FVIII were restored to 148 mg/dL, 54%, and 81%. The pO2/FIO2 was 282. The early post-OR study showed a PT of 2.3 seconds off normal (international normalized ratio = 1.2), a PTT of 32 seconds, a TT of 7.2 seconds off normal, an FI of 207 mg/dL, an FV of 64%, an FVIII of 102%, and a pO2/FIO2 of 332. Both OR and early post-OR CTs and procoagulant levels are associated with adequate coagulation. All patients with a 0.31:1 or higher FFP/RBC had sufficient restoration of CTs and procoagulants.

CONCLUSION

These data show that an FFP/RBC ratio above 0.31:1 in injured patients requiring MT restores CTs and procoagulant to clinically effective levels while not causing adult respiratory distress syndrome. Future studies on defining the ideal FFP/RBC ratio for MT should monitor CTs, procoagulants, and organ function.

The evolution of damage control surgery

The philosophy of damage control surgery has developed tremendously over the past 10 years. It has expanded outside the original boundaries of the abdomen and has been applied to all aspects of trauma care, ranging from resuscitation to limb-threatening vascular injuries. In recent years, the US military has taken the concept to a new level by initiating a damage control approach at the point of injury and continuing it through a transcontinental health care system. This article highlights many recent advances in damage control surgery and discusses proper patient selection and the risks associated with this management strategy.

Tips and tricks for the trauma patient

Interventions on the trauma patient are an essential component of the complete scope of care that is provided to the multiply injured patient today. The active participation by the interventional radiologist along the entire spectrum of clinical care is very important to optimize patient outcomes. Suggestions on how to establish a clinical presence are presented. A few of the newer concepts and terminology applicable to trauma care are reviewed. Tips useful in the trauma room, in the interventional radiology suite, and during the postprocedural period are discussed.

[Blood transfusion in emergency settings: French military health service experience]

Blood transfusion is required in a number of emergency settings and the French military health service (FMHS) has issued specific guidelines for the treatment of war casualties. These guidelines take into account European standards and laws, NATO standards, and also public sentiment regarding transfusion. These guidelines reflect a determination to control the process and to avoid the improvisation frequently associated with wartime transfusion. The evolution in warfare (terrorism and bombing more frequent than gunshot) and the wide use of body armor have deeply changed the clinical presentation of war injuries. These now involve the extremities in 80% of cases, with extensive tissue damage and heavy blood loss. The FMHS recommends that war casualties with hemorrhagic shock be brought quickly to a medical treatment facility (MTF) after first-line treatment applied through buddy aid or by medics. In the MTF, before an early Medevac, a damage control surgery will be performed, with resuscitation using freeze-dried plasma, red blood cells and fresh whole blood. The French military blood bank is responsible for blood product supply, training and medical advice regarding transfusion therapy during wartime, as well as hemovigilance. All transfusion therapy practices are periodically assessed but research on whole blood pathogen reduction is being conducted in order to reduce the residual infectious risk associated with this product.

Creation, implementation, and maturation of a massive transfusion protocol for the exsanguinating trauma patient

The majority of trauma patients (>90%) do not require any blood product transfusion and their mortality is <1%. However, 3% to 5% of civilian trauma patients will receive a massive transfusion (MT), defined as >10 units of packed red blood cells (PRBC) in 24 hours. In addition, more than 25% of these patients will arrive to emergency departments with evidence of trauma-associated coagulopathy. With this combination of massive blood loss and coagulopathy, it has become increasingly more common to transfuse early the trauma patients and with a combination of PRBC, plasma, and platelets. Given the inherent uncertainties common early in the care of patients with severe injuries, the efficient administration of massive amounts of PRBC and clotting factors tends to work best in a predefined, protocol driven system. Our purpose here is to (1) define the problem of massive hemorrhage and coagulopathy in the trauma patient, (2) identify which group of patients this type of protocol should be applied, (3) describe the extensive coordination required to implement this multispecialty MT protocol, (4) explain in detail how the MT was developed and implemented, and (5) emphasize the need for a robust performance improvement or quality improvement process to monitor the implementation of such a protocol and to help identify problems and deliver feedback in a "real-time" fashion. The successful implementation of such a complex process can only be accomplished in a multispecialty setting. Input and representation from departments of Trauma, Critical Care, Anesthesiology, Transfusion Medicine, and Emergency Medicine are necessary to successfully formulate (and implement) such a protocol. Once a protocol has been agreed upon, education of the entire nursing and physician staff is equally essential to the success of this effort. Once implemented, this process may lead to improved clinical outcomes and decreased overall blood utilization with extremely small wastage of vital blood products.

Transfusion therapy in hemorrhagic shock

PURPOSE OF REVIEW

Bleeding and death from hemorrhage remain a leading cause of morbidity and mortality in the trauma population. Early resuscitation of these gravely injured patients has changed significantly over the past several years. The concept of damage control resuscitation has expanded significantly with the experience of the US military in southwest Asia. This review will focus on this resuscitation strategy of transfusing blood products (red cells, plasma, and platelets) early and often in the exsanguinating patient.

RECENT FINDINGS

In trauma there are no randomized controlled trials comparing the current damage control hematology concept to more traditional resuscitation methods. But the overwhelming conclusion of the data available support the administration of a high ratio of plasma and platelets to packed red blood cells. Several large retrospective studies have shown ratios close to 1: 1 will result in higher survival.

SUMMARY

The current evidence supports that the acute coagulopathy of trauma is present in a high percentage of trauma patients. Patients who will require a massive transfusion will have improved outcomes the earlier that this is identified and the earlier that damage control hematology is instituted. Current evidence does not describe the best ratio but the preponderance of the data suggests it should be greater than 2: 3 plasma-to-packed red blood cells.

Increased plasma and platelet to red blood cell ratios improves outcome in 466 massively transfused civilian trauma patients

OBJECTIVE

To determine the effect of blood component ratios in massive transfusion (MT), we hypothesized that increased use of plasma and platelet to red blood cell (RBC) ratios would result in decreased early hemorrhagic death and this benefit would be sustained over the ensuing hospitalization.

SUMMARY BACKGROUND DATA

Civilian guidelines for massive transfusion (MT > or =10 units of RBC in 24 hours) have typically recommend a 1:3 ratio of plasma:RBC, whereas optimal platelet:RBC ratios are unknown. Conversely, military data shows that a plasma:RBC ratio approaching 1:1 improves long term outcomes in MT combat casualties. There is little consensus on optimal platelet transfusions in either civilian or military practice. At present, the optimal combinations of plasma, platelet, and RBCs for MT in civilian patients is unclear.

METHODS

Records of 467 MT trauma patients transported from the scene to 16 level 1 trauma centers between July 2005 and June 2006 were reviewed. One patient who died within 30 minutes of admission was excluded. Based on high and low plasma and platelet to RBC ratios, 4 groups were analyzed.

RESULTS

Among 466 MT patients, survival varied by center from 41% to 74%. Mean injury severity score varied by center from 22 to 40; the average of the center means was 33. The plasma:RBC ratio ranged from 0 to 2.89 (mean +/- SD: 0.56 +/- 0.35) and the platelets:RBC ratio ranged from 0 to 2.5 (0.55 +/- 0.50). Plasma and platelet to RBC ratios and injury severity score were predictors of death at 6 hours, 24 hours, and 30 days in multivariate logistic models. Thirty-day survival was increased in patients with high plasma:RBC ratio (> or =1:2) relative to those with low plasma:RBC ratio (<1:2) (low: 40.4% vs. high: 59.6%, P < 0.01). Similarly, 30-day survival was increased in patients with high platelet:RBC ratio (> or =1:2) relative to those with low platelet:RBC ratio (<1:2) (low: 40.1% vs. high: 59.9%, P < 0.01). The combination of high plasma and high platelet to RBC ratios were associated with decreased truncal hemorrhage, increased 6-hour, 24-hour, and 30-day survival, and increased intensive care unit, ventilator, and hospital-free days (P < 0.05), with no change in multiple organ failure deaths. Statistical modeling indicated that a clinical guideline with mean plasma:RBC ratio equal to 1:1 would encompass 98% of patients within the optimal 1:2 ratio.

CONCLUSIONS

Current transfusion practices and survival rates of MT patients vary widely among trauma centers. Conventional MT guidelines may underestimate the optimal plasma and platelet to RBC ratios. Survival in civilian MT patients is associated with increased plasma and platelet ratios. Massive transfusion practice guidelines should aim for a 1:1:1 ratio of plasma:platelets:RBCs.

Recent experiences with a multidisciplinary approach to complex hepatic trauma

BACKGROUND

The selection of an appropriate time to terminate damage control efforts when faced with haemorrhagic shock from severe hepatic trauma can be challenging. At our centre, trauma surgeons have increasingly been favouring an operative approach simply involving early perihepatic packing (without extensive use of intraoperative measures aimed at achieving definitive haemostasis) and temporary abdominal closure. This is often followed by hepatic arteriography with angioembolization, resuscitation, and early re-exploration under more optimal physiological conditions. This study describes the initial outcomes of this approach.

MATERIALS AND METHODS

All patients with high-grade liver injury requiring operative intervention due to refractory haemodynamic instability, presenting to our trauma centre between 1995 and 2001 were reviewed. Two treatment groups: definitive laparotomy (DL), and early packing (EP) with angioembolization and re-exploration were compared, using a retrospective audit.

RESULTS

Thirty-seven patients were identified with severe liver injuries requiring operative intervention (DL 30, EP 7). Patient demographics between groups were similar. The EP group was found to have lower mortality (0% versus 36.7%), but increased length of hospital stay, transfusion requirements, and complication rates.

CONCLUSIONS

A multidisciplinary approach to complex hepatic trauma involving brief damage control laparotomy with perihepatic packing only, followed by angioembolization, and early re-exploration may confer a survival benefit over early operative attempts at definitive haemostasis but is associated with complications.

A review of studies on the effects of hemorrhagic shock and resuscitation on the coagulation profile

BACKGROUND

This study reports on the results of hemorrhagic shock (HS) plus resuscitation on the coagulation profile in severely injured patients and on the role of fresh frozen plasma (FFP) supplementation in a canine HS model.

CLINICAL STUDIES

Primary hemostasis (platelet plug), secondary hemostasis (fibrin clot), and fibrinolysis were assayed in 22 injured patients who received an average of 21 units of packed red blood cells (PRBCs), 16.5 L crystalloid solution, and 1.25 L FFP during operation for control of bleeding. Measurements were obtained during operation and postoperatively at 5, 15, 36, and 84 hours and at 26 days. The platelet count during operation was 113,000/mm3, decreased to a nadir of 76,000/mm3 at 48 hours, and then increased to 563,000/mm2 by convalescence. Platelets were not given with resuscitation. The bleeding times and aggregation studies mirrored platelet levels until convalescence. HS led to significant reductions in fibrinogen (factor I), factor V, and factor VIII that normalized by day 1. The fibrinogen increased to supranormal levels by day 4 through day 26. Clotting times mirrored fibrinogen, factor V, and factor VIII levels. Fibrin split products were normal during operation and increased postoperatively through day 26. The increase in fibrin split products paralleled the increase in fibrinogen.

EXPERIMENTAL STUDIES

The role of FFP supplementation in HS resuscitation was tested in two separate studies. After HS, the animals were resuscitated with shed blood and crystalloid; half the animals also received FFP. FFP did not improve the coagulation factors, fibrinogen and factors II, V, VII, and VIII. Thus, routine FFP supplementation for HS in humans was abandoned. This led to unexpected postoperative bleeding that in one instance caused death. Therefore, a second controlled study was used in which the FFP was given not only during blood volume restoration but also for an additional hour during continued ongoing controlled hemorrhage without shock. The second study demonstrated that the FFP prevented the reduction in coagulation factors compared with animals not receiving FFP. Clotting times paralleled coagulation protein levels. FFP is now used to supplement HS resuscitation in humans.

CONCLUSION

Resuscitation from hemorrhagic shock can be successfully implemented by restoration of blood loss with blood, crystalloid, and FFP added to maintain coagulation proteins.

Postoperative care and complications of damage control surgery

Damage control procedures are being used with increasing frequency as the physiologic limits of the surgical patient are approached and recognized. These patients are returned to the SICU, where rapid restoration of circulating volume, normothermia, maintenance of oxygen delivery, and correction of transfusion-associated coagulopathy are essential to the success of the technique, which requires expeditious reoperation and completion of definitive surgical management. The potential need for early return to the operating room to control surgical bleeding must be recognized, as well as the difficulty in distinguishing between surgical bleeding and ongoing hemorrhage due to hypothermia and coagulopathy. Because the damage control technique is resource intensive and involves numerous personnel, organization and leadership are important to success.