Abnormal Calcium Levels During Trauma Resuscitation Are Associated With Increased Mortality, Increased Blood Product Use, and Greater Hospital Resource Consumption: A Pilot Investigation

Hemostatic defects in massive transfusion: an update and treatment recommendations

INTRODUCTION

Acute hemorrhage is a global healthcare issue, and remains the leading preventable cause of death in trauma. Acute severe hemorrhage can be related to traumatic, peripartum, gastrointestinal, and procedural causes. Hemostatic defects occur early in patients requiring massive transfusion. Early recognition and treatment of hemorrhage and hemostatic defects are required to save lives and to achieve optimal patient outcomes.

AREAS COVERED

This review discusses current evidence and trials aimed at identifying the optimal treatment for hemostatic defects in hemorrhage and massive transfusion. Literature search included PubMed and Embase.

EXPERT OPINION

Patients with acute hemorrhage requiring massive transfusion commonly develop coagulopathy due to specific hemostatic defects, and accurate diagnosis and prompt correction are required for definitive hemorrhage control. Damage control resuscitation and massive transfusion protocols are optimal initial treatment strategies, followed by goal-directed individualized resuscitation using real-time coagulation monitoring. Distinct phenotypes exist in trauma-induced coagulopathy, including 'Bleeding' or 'Thrombotic' phenotypes, and hyperfibrinolysis vs. fibrinolysis shutdown. The trauma 'lethal triad' (hypothermia, coagulopathy, acidosis) has been updated to the 'lethal diamond' (including hypocalcemia). A number of controversies in optimal management exist, including whole blood vs. component therapy, use of factor concentrates vs. blood products, optimal use of tranexamic acid, and prehospital plasma and tranexamic acid administration.

Reperfusion repercussions: A review of the metabolic derangements following resuscitative endovascular balloon occlusion of the aorta

BACKGROUND

Current resuscitative endovascular balloon occlusion of the aorta (REBOA) literature focuses on improving outcomes through careful patient selection, diligent catheter placement, and expeditious definitive hemorrhage control. However, the detection and treatment of post-REBOA ischemia-reperfusion injury (IRI) remains an area for potential improvement. Herein, we provide a review of the metabolic derangements that we have encountered while managing post-REBOA IRI in past swine experiments. We also provide data-driven clinical recommendations to facilitate resuscitation post-REBOA deflation that may be translatable to humans.

METHODS

We retrospectively reviewed the laboratory data from 25 swine across three varying hemorrhagic shock models that were subjected to complete REBOA of either 45 minutes, 60 minutes, or 90 minutes. In each model the balloon was deflated gradually following definitive hemorrhage control. Animals were then subjected to whole blood transfusion and critical care with frequent electrolyte monitoring and treatment of derangements as necessary.

RESULTS

Plasma lactate peaked and pH nadired long after balloon deflation in all swine in the 45-minute, 60-minute, and 90-minute occlusion models (onset of peak lactate, 32.9 ± 6.35 minutes, 38.8 ± 10.55 minutes, and 49.5 ± 6.5 minutes; pH nadir, 4.3 ± 0.72 minutes, 26.9 ± 12.32 minutes, and 42 ± 7.45 minutes after balloon deflation in the 45-, 60-, and 90-minute occlusion models, respectively). All models displayed persistent hypoglycemia for more than an hour following reperfusion (92.1 ± 105.5 minutes, 125 ± 114.9 minutes, and 96 ± 97.8 minutes after balloon deflation in the 45-, 60-, and 90-minute occlusion groups, respectively). Hypocalcemia and hyperkalemia occurred in all three groups, with some animals requiring treatment more than an hour after reperfusion.

CONCLUSION

Metabolic derangements resulting from REBOA use are common and may worsen long after reperfusion despite resuscitation. Vigilance is required to detect and proactively manage REBOA-associated IRI. Maintaining a readily available "deflation kit" of pharmacological agents needed to treat common post-REBOA electrolyte abnormalities may facilitate management.

LEVEL OF EVIDENCE

Level V.

The diamond of death: Hypocalcemia in trauma and resuscitation

INTRODUCTION

Early recognition and management of hemorrhage, damage control resuscitation, and blood product administration have optimized management of severe trauma. Recent data suggest hypocalcemia exacerbates the ensuing effects of coagulopathy in trauma.

OBJECTIVE

This narrative review of available literature describes the physiology and role of calcium in trauma resuscitation. Authors did not perform a systematic review or meta-analysis.

DISCUSSION

Calcium is a divalent cation found in various physiologic forms, specifically the bound, inactive state and the unbound, physiologically active state. While calcium plays several important physiologic roles in multiple organ systems, the negative hemodynamic effects of hypocalcemia are crucial to address in trauma patients. The negative ramifications of hypocalcemia are intrinsically linked to components of the lethal triad of acidosis, coagulopathy, and hypothermia. Hypocalcemia has direct and indirect effects on each portion of the lethal triad, supporting calcium's potential position as a fourth component in this proposed lethal diamond. Trauma patients often present hypocalcemic in the setting of severe hemorrhage secondary to trauma, which can be worsened by necessary transfusion and resuscitation. The critical consequences of hypocalcemia in the trauma patient have been repeatedly demonstrated with the associated morbidity and mortality. It remains poorly defined when to administer calcium, though current data suggest that earlier administration may be advantageous.

CONCLUSIONS

Calcium is a key component of trauma resuscitation and the coagulation cascade. Recent data portray the intricate physiologic reverberations of hypocalcemia in the traumatically injured patient; however, future research is needed to further guide the management of these patients.

Damage control strategy in bleeding trauma patients

Hemorrhagic shock is a main cause of death in severe trauma patients. Bleeding trauma patients have coagulopathy on admission, which may even be aggravated by incorrectly directed resuscitation. The damage control strategy is a very urgent and essential aspect of management considering the acute coagulopathy of trauma and the physiological status of bleeding trauma patients. This strategy has gained popularity over the past several years. Patients in extremis cannot withstand prolonged definitive surgical repair. Therefore, an abbreviated operation, referred to as damage control surgery (DCS), is needed. In addition to DCS, the likelihood of survival should be maximized for patients in extremis by providing appropriate critical care, including permissive hypotension, hemostatic resuscitation, minimization of crystalloid use, early use of tranexamic acid, and avoidance of hypothermia and hypocalcemia. This review presents an overview of the evolving strategy of damage control in bleeding trauma patients.

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.

Hypocalcemia and Massive Blood Transfusions: A Pilot Study in a Level I Trauma Center

Trauma is a leading cause of death in the United States, and uncontrolled hemorrhage is often the primary cause of mortality. Massive transfusions provide lifesaving treatment for the bleeding trauma patient; yet, this is not a benign intervention. Calcium levels can be significantly decreased with rapidly transfused blood products due to the citrate preservative that is added. Citrate binds to the patient's endogenous calcium when blood products are administered, rendering calcium inactive. As a result, undesirable physiological effects can occur. Although there is a plethora of evidence reporting the negative effects of hypocalcemia during resuscitation, the research for standardization of calcium monitoring and replacement during a massive transfusion event is less robust. Consequently, monitoring and replacement of this vital electrolyte are often overlooked. Trauma department employees at an urban academic hospital were given a pretest to assess their knowledge of calcium monitoring and replacement during a massive transfusion. On the basis of test results and a need for staff education, a short, animated video was designed and distributed for viewing. Following the educational video, a posttest was administered and yielded higher scores when compared with the pretest (p = .001). Lack of knowledge and national standards may be root causes for hypocalcemia. Educational interventions such as innovative, brief videos can be effective for enhancing staff members' knowledge and improving patient care.