Massive transfusion in traumatic shock

Higher Doses of Calcium Associated With Survival in Trauma Patients

INTRODUCTION

Calcium is required for coagulation, cardiac output, and peripheral vascular resistance. Between 85% and 94% of trauma patients treated with massive blood transfusion develop hypocalcemia.1 The aim of this study is to evaluate the relationship between increased intravenous calcium administration during massive transfusion and improved survival of trauma patients.

METHODS

We performed a retrospective analysis of trauma patients who received massive transfusion over a 2-y period. Doses of elemental calcium administered per unit of blood product transfused were calculated by calcium to blood product ratio (CBR). Chi-square test evaluated association between coagulopathy and 30-d mortality. Two-sample t-test evaluated association between CBR and coagulopathy. Bivariate regression analysis evaluated association between CBR and blood products transfused per patient. Multivariable logistic regression analysis, controlling for age, sex, coagulopathy, and Injury Severity Score evaluated the association between CBR and mortality.

RESULTS

The study included 77 patients. Coagulopathy was associated with increased 30-d mortality (P < 0.05). Patients who survived had higher CBR than those who died (P < 0.05). CBR was associated with a significant reduction in total blood products transfused per patient (P < 0.05). CBR was not associated with coagulopathy (P = 0.24). Multivariable logistic regression analysis demonstrated that Injury Severity Score ≥16, coagulopathy and decreased CBR were significant predictors of mortality (P < 0.05). CBR above 50 mg was a predictor of survival (P < 0.05).

CONCLUSIONS

Higher doses of calcium given per blood product transfused were associated with improved 30-d survival and decreased blood product transfusions.

Management of Postpartum Hemorrhage in Critical Care Transport

Postpartum hemorrhage is a relatively common and highly morbid complication of the postpartum period that often requires management by specialized providers at tertiary care facilities. Critical care transport teams may be tasked with transporting postpartum patients who are already experiencing postpartum hemorrhage, but they should also be aware that other peripartum patients may be at risk for developing postpartum hemorrhage while in the process of transport. As such, it is imperative that transport providers understand the signs, symptoms, causes, and complications of postpartum hemorrhage as well as the options for intervention and treatment. This article reviews the current clinical evidence regarding resuscitation and medical management strategies that transport teams should be familiar with as well as more advanced and invasive management techniques they may encounter and be expected to monitor during transport, such as balloon tamponade and aortic balloon occlusion.

EVALUATION OF TRANEXAMIC ACID AND CALCIUM CHLORIDE IN MAJOR TRAUMAS IN A PREHOSPITAL SETTING: A NARRATIVE REVIEW

ABSTRACT

Excessive blood loss in the prehospital setting poses a significant challenge and is one of the leading causes of death in the United States. In response, emergency medical services (EMS) have increasingly adopted the use of tranexamic acid (TXA) and calcium chloride (CaCl 2 ) as therapeutic interventions for hemorrhagic traumas. Tranexamic acid functions by inhibiting plasmin formation and restoring hemostatic balance, while calcium plays a pivotal role in the coagulation cascade, facilitating the conversion of factor X to factor Xa and prothrombin to thrombin. Despite the growing utilization of TXA and CaCl 2 in both prehospital and hospital environments, a lack of literature exists regarding the comparative effectiveness of these agents in reducing hemorrhage and improving patient outcomes. Notably, Morgan County Indiana EMS recently integrated the administration of TXA with CaCl 2 into their treatment protocols, offering a valuable opportunity to gather insight and formulate updated guidelines based on patient-centered outcomes. This narrative review aims to comprehensively evaluate the existing evidence concerning the administration of TXA and CaCl 2 in the prehospital management of hemorrhages, while also incorporating and analyzing data derived from the co-administration of these medications within the practices of Morgan County EMS. This represents the inaugural description of the concurrent use of both TXA and CaCl 2 to manage hemorrhages in the scientific literature.

Defining the optimal calcium repletion dosing in patients requiring activation of massive transfusion protocol

PURPOSE

Massive transfusion protocols (MTP) commonly result in severe hypocalcemia due to the calcium-binding affinity of citrate in blood components. The purpose of this study is to determine the optimal grams (g) of citrate to repletion calcium (Ca) milliequivalents (mEq) (Citrate:Ca) ratio to reduce 30-day mortality.

METHODS

This was a retrospective, single-centered, cohort study at a level 1 trauma center evaluating trauma and surgical patients in need of MTP activation from January 1, 2010-July 31, 2021. Patients with severe hypocalcemia at baseline, defined as ionized calcium (iCa) <0.9 mmol/L, were compared to patients without severe hypocalcemia. The primary endpoint was to determine the optimal ratio of grams of citrate to calcium mEq to reduce mortality in patients receiving a MTP. Secondary endpoints included mortality at 24 h and 30 days, blood components used in MTP, and type of calcium used.

RESULTS

Overall, 501 patients were screened for inclusion. Of these patients, 193 were excluded, leaving 308 patients, of which 165 patients (53.6%) had an iCa <0.9 mmol/L within 24 h and 143 patients (46.4%) had iCa ≥0.9 mmol/L within 24 h. The ratio of Citrate:Ca for each patient was not significantly associated with mortality at 24 h (P = 0.79) or 30 days (P = 0.91) at a repletion Citrate:Ca ratio of median 1.97 (IQR 1.14-2.91). The rate of mortality was lowest at a Citrate:Ca of 2 in both <24-h mortality and 30-day mortality.

CONCLUSIONS

There were no differences in 24 h or 30 day mortality based on repletion ratios seen in this study. A Citrate:Ca ratio between 2 and 3 in patients undergoing MTP was sufficient to obtain a normalized iCa within 24 h of MTP activation regardless of baseline iCa level. Further prospective studies will be needed to determine the optimal Citrate:Ca ratio.

Interventions of Postpartum Hemorrhage

Postpartum hemorrhage is a common and potentially life-threatening obstetric complication, with successful management relying heavily on early identification of hemorrhage and prompt intervention. This article will review the management of postpartum hemorrhage, including initial steps, exam-specific interventions, medical therapy, minimally invasive, and surgical interventions.

Implementation of a Multimodal Interdisciplinary Massive Transfusion Protocol Educational Bundle Improves Knowledge and Self-Efficacy

PURPOSE

Critical events in the operative setting require rapid management to prevent adverse outcomes. This article describes a multimodal educational bundle that was designed and implemented to improve readiness to respond to crises involving significant blood loss. Intended outcomes of this project were to increase knowledge and self-efficacy of anesthesia providers and perioperative staff members related to the use of the massive transfusion protocol (MTP).

DESIGN

This is a quality improvement (QI) project.

METHODS

A two-part educational bundle consisted of pre-education and low-fidelity simulation (LFS) via computer-based training (CBT) modules followed by hands-on skills sessions. Anesthesia providers, registered nurses, and technicians in the operative suite completed the educational intervention. Knowledge and self-efficacy were measured pre-and-post intervention.

FINDINGS

After completing the educational bundle, the aggregated mean score on a knowledge test increased by 5.65%. Self-efficacy related to role-specific responsibilities and confidence regarding the team's ability to carry out the MTP significantly increased for all participants (n = 62).

CONCLUSIONS

This project serves as an example of how a multimodal educational bundle can improve knowledge, confidence, and readiness to respond to critical events. This model demonstrates how pre-education and LFS enable crisis management training to be readily accessible for an entire interdisciplinary team.

Pre-hospital blood products and calcium replacement protocols in UK critical care services: A survey of current practice

Introduction

In the United Kingdom, prehospital blood products are increasingly carried for the early resuscitation of hypovolaemia in patients who are shocked or in cardiac arrest. There is an association between hypocalcaemia and mortality in trauma patients, but no current national guidelines on the timing or dose of calcium replacement exist. The objective of this study was to establish the availability of prehospital blood products, and the current calcium replacement protocols used by UK prehospital services.

Methods

A cross sectional survey of all UK air ambulances and additional prehospital critical care organisations was conducted in April-May 2022 via an on-line questionnaire. The survey asked 11 questions about availability of prehospital blood products, calcium replacement for patients requiring prehospital blood products, and the use of point of care testing.

Results

There was a 100% response rate with 20/22 UK air ambulances carrying blood products and five additional prehospital services identified. There were 15 different combinations of prehospital blood products. 23/25 services had a standard operating procedure for the replacement of calcium. This was recommended before any blood product administration in 5 services (22%), during or after the 1st unit in 5 services (22%), during or after the 2nd unit in 6 services (26%) and during or after the 4th unit in 7 services (30%). Only six services carried point of care testing and no services routinely used this to measure calcium levels in patients requiring prehospital blood products.

Conclusion

In 2022, 91% of UK air ambulances carry prehospital blood products and there is significant variation between services in the combination of blood products provided. There is no consensus on the timing or dose of calcium replacement. Further prospective research should examine the association between traumatic bleeding and ionized calcium levels before and during blood product transfusion in order to produce more robust guidelines for routine calcium replacement.

Postpartum Hemorrhage Management and Blood Component Therapy

This article serves to highlight both the common nature and severity of postpartum hemorrhage (PPH). Identification of etiologies and management of each is reviewed. In addition, the evaluation and administration of proper blood component therapies and massive transfusion are also explained to help providers become comfortable with early administration and delivery of blood component therapies.

Advancing in the understanding of coagulopathy during hemorrhagic shock: From the triad to the deadly pentad

The deadly triad concept represented a dogma in the definition of poor outcomes and death associated with major bleeding in trauma. This model of end-stage disease was then rapidly transferred to other major bleeding scenarios. However, and notwithstanding the fact that it represented a severe scenario, the original triad fails to establish a sequence, which would be relevant when defining the objectives during the initial treatment of severe bleeding.  It has been recently suggested that hypoxia and hyperglycemia should be included as isolated, determining factors in this model. Likewise, the model admits only one scenario where all the conditions shall co-exist, knowing that each one of them contributes with a different risk burden. Based on a structured review, we submit a pentad model that includes a natural pattern of events occurring with hypoxemia as the main trigger for the development of hypocalcemia, hyperglycemia, acidosis and hypothermia, as hallmarks of multiple system impairment. This severity model of major bleeding ends with coagulopathy as a result of the failure to resolve the rest of the previous components.

Mechanistic Modeling of Placental Drug Transfer in Humans: How Do Differences in Maternal/Fetal Fraction of Unbound Drug and Placental Influx/Efflux Transfer Rates Affect Fetal Pharmacokinetics?

Background: While physiologically based pharmacokinetic (PBPK) models generally predict pharmacokinetics in pregnant women successfully, the confidence in predicting fetal pharmacokinetics is limited because many parameters affecting placental drug transfer have not been mechanistically accounted for. Objectives: The objectives of this study were to implement different maternal and fetal unbound drug fractions in a PBPK framework; to predict fetal pharmacokinetics of eight drugs in the third trimester; and to quantitatively investigate how alterations in various model parameters affect predicted fetal pharmacokinetics. Methods: The ordinary differential equations of previously developed pregnancy PBPK models for eight drugs (acyclovir, cefuroxime, diazepam, dolutegravir, emtricitabine, metronidazole, ondansetron, and raltegravir) were amended to account for different unbound drug fractions in mother and fetus. Local sensitivity analyses were conducted for various parameters relevant to placental drug transfer, including influx/efflux transfer clearances across the apical and basolateral membrane of the trophoblasts. Results: For the highly-protein bound drugs diazepam, dolutegravir and ondansetron, the lower fraction unbound in the fetus vs. mother affected predicted pharmacokinetics in the umbilical vein by ≥10%. Metronidazole displayed blood flow-limited distribution across the placenta. For all drugs, umbilical vein concentrations were highly sensitive to changes in the apical influx/efflux transfer clearance ratio. Additionally, transfer clearance across the basolateral membrane was a critical parameter for cefuroxime and ondansetron. Conclusion: In healthy pregnancies, differential protein binding characteristics in mother and fetus give rise to minor differences in maternal-fetal drug exposure. Further studies are needed to differentiate passive and active transfer processes across the apical and basolateral trophoblast membrane.

Hypocalcemia in Military Casualties From Point of Injury to Surgical Teams in Afghanistan

INTRODUCTION

Hypocalcemia is a known sequela of citrated blood product transfusion. Civilian data suggest hypocalcemia on hospital admission is associated with worse outcomes. Initial calcium levels in military casualties have not previously been analyzed. The objective of this retrospective review aimed to assess the initial calcium levels in military trauma casualties at different Forward Surgical Teams (FST) locations in Afghanistan and describe the effects of prehospital blood product administration on arrival calcium levels.

MATERIALS AND METHODS

This is a retrospective cohort analysis of military casualties arriving from point of injury to one of two FSTs in Afghanistan from August 2018 to February 2019 split into four locations. The primary outcome was incidence of hypocalcemia (ionized calcium < 1.20 mmol/L).

RESULTS

There were 101 patients included; 55 (54.5%) experienced hypocalcemia on arrival to the FST with a mean calcium of 1.16 mmol/L (95% confidence interval [CI], 1.14 to 1.18). The predominant mechanism of injury consisted of blast patterns, 46 (45.5%), which conferred an increased risk of hypocalcemia compared to all other patterns of injury (odds ratio = 2.42, P = .042). Thirty-eight (37.6%) patients required blood product transfusion. Thirty-three (86.8%) of the patients requiring blood product transfusion were hypocalcemic on arrival. Mean initial calcium of patients receiving blood product was 1.13 mmol/L (95% CI, 1.08 to 1.18), which was significantly lower than those who did not require transfusion (P = .01). Eight (7.9%) of the patients received blood products before arrival, with 6/8 (75%) presenting with hypocalcemia.

CONCLUSIONS

Hypocalcemia develops rapidly in military casualties and is prevalent on admission even before transfusion of citrated blood products. Blast injuries may confer an increased risk of developing hypocalcemia. This data support earlier use of calcium supplementation during resuscitation.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) transfusion reaction small animal consensus statement (TRACS). Part 3: Diagnosis and treatment

OBJECTIVE

To systematically review available evidence to develop guidelines for diagnosis and treatment of transfusion-associated reactions in dogs and cats.

DESIGN

Standardized and systemic evaluation of the literature (identified through Medline via PubMed and Google Scholar searches) was carried out for identified transfusion reaction types in dogs and cats. The available evidence was evaluated using PICO (Population, Intervention, Comparison, Outcome) questions generated for each reaction type. The evidence was categorized by level of evidence (LOE) and quality (Good, Fair, or Poor). Guidelines, diagnostic, and treatment algorithms were generated based on the evaluation of the evidence. Consensus on the final guidelines was achieved through Delphi-style surveys. Draft recommendations were disseminated through veterinary specialty listservs for review and comments, which were evaluated and integrated prior to final publication.

RESULTS

Medline via PubMed and Google Scholar databases were searched. There were 14 Population Intervention Comparison Outcome questions identified and corresponding worksheets were developed focusing on the diagnosis and treatment of transfusion-associated reactions in dogs and cats. Fourteen guidelines and four algorithms were developed with a high degree of consensus.

CONCLUSIONS

This systematic evidence evaluation process yielded recommended diagnostic and treatment algorithms for use in practice. However, significant knowledge gaps were identified, demonstrating the need for additional research in veterinary transfusion medicine.

Hypocalcemia in trauma patients: A systematic review

BACKGROUND

During hemorrhagic shock and subsequent resuscitation, pathways reliant upon calcium such as platelet function, intrinsic and extrinsic hemostasis, and cardiac contractility are disrupted. The objective of this systematic review was to examine current literature for associations between pretransfusion, admission ionized hypocalcemia, and composite outcomes including mortality, blood transfusion requirements, and coagulopathy in adult trauma patients.

METHODS

This review was reported using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses checklist. We searched Ovid MEDLINE and grey literature from database inception till May 3, 2020. Case series and reports were excluded. Reference lists of appraised studies were also screened for articles that the aforementioned databases might not have captured. The Newcastle-Ottawa Scale was used to assess study quality.

RESULTS

A total of 585 abstracts were screened through database searching and alternative sources. Six unique full-text studies were reviewed, of which three were excluded. Admission ionized hypocalcemia was present in up to 56.2% of the population in studies included in this review. Admission ionized hypocalcemia was also associated with increased mortality in all three studies, with increased blood transfusion requirements in two studies, and with coagulopathy in one study.

CONCLUSION

Hypocalcemia is a common finding in shocked trauma patients. While an association between admission ionized hypocalcemia and mortality, blood transfusion requirements, and coagulopathy has been identified, further prospective trials are essential to corroborating this association.

LEVEL OF EVIDENCE

Systematic review, level III.

Using Simulation-Based Education to Improve Team Communication During a Massive Transfusion Protocol in the OR

Hemorrhaging during operative and other invasive procedures can result in devastating outcomes for surgical patients. An effective plan of action in the form of a massive transfusion protocol (MTP), along with teamwork and clear communication among OR personnel, is critical during a hemorrhagic crisis to improve patient outcomes. However, perioperative personnel may be unprepared to manage a hemorrhagic crisis because they lack experiential knowledge of these uncommon, high-risk scenarios. Perioperative leaders at a 500-bed acute-care hospital in the Midwest developed an educational activity involving a video-recorded simulated MTP scenario, learning modules, and debriefing sessions to educate more than 150 employees. Perioperative personnel received pre-education and watched the video-recorded MTP simulation together, and then participated in team debriefings after watching the video. Based on team debriefings and evaluation feedback, most staff members believed that the activity improved team communication.

Extracorporeal Membrane Oxygenation in Transport Part 2: Complications and Troubleshooting

Factors taken for granted while the extracorporeal membrane oxygenation (ECMO) patient is maintained in a hospital setting can become critical when planning for transport. These issues include but are not limited to positioning of patients on a small transport stretcher, positioning of cannulas and equipment, ensuring adequate power sources and supply, inefficient temperature control, and a much higher risk of decannulation. It is paramount to be comfortable with the management strategies required to handle common complications of ECMO with limited resources in a relatively austere environment. Coagulopathy and bleeding are the most common complications occurring in up to 50% of ECMO patients. Loss of flow and hypotension from loss of volume or profound vasodilation after ECMO initiation need to be managed accordingly. Oxygenator malfunction can occur, and clinicians must be able to recognize the indicators of this complication promptly. Loss of pulsatility, low end-tidal carbon dioxide (ETCO₂), and differential hypoxia are common complications in venoarterial ECMO. In addition, an air embolism is life-threatening on venoarterial ECMO but may be better tolerated in the setting of venovenous ECMO. Recirculation in venovenous ECMO leads to circulation of poorly oxygenated blood and must be recognized and addressed. Lastly, pump failure, circuit rupture, and decannulation are devastating complications. Over the last decade, the use of extracorporeal membrane oxygenation (ECMO) has accelerated rapidly,^1-3 providing support for patients in severe respiratory or cardiac failure. With ongoing clinical experience and improvements in technology, the indications for ECMO are increasing.⁴ Many areas are developing centralized ECMO centers to serve their surrounding communities.^5-7 To use a centralized ECMO referral model, patients need access to effective, safe critical care transport, but transporting a patient on ECMO carries a significant risk of adverse events.^8-13 The purpose of this review is to highlight some of the most common adverse events in ECMO transports and provide management suggestions. Note that these recommendations are not a substitution for close collaboration with medical control, and all adverse events should be promptly reported per organizational protocols.

Implementation of a Massive Transfusion Protocol: Evaluation of Its Use and Efficacy

Massive transfusion protocols (MTPs) allow practitioners to follow a prescribed algorithm for the rapid replacement of blood products during a massive hemorrhage. They function as an established protocol to provide consistent treatment. Once implemented, the MTP must be evaluated to ensure best practice. The purpose of this clinical improvement project was to formally evaluate the use and efficacy of an MTP during its first year of implementation. The specific aims were to (1) determine whether MTP activations were missed; (2) compare outcomes between those patients managed by the MTP and those who were not; and (3) provide recommendations to the institution's stakeholders. A retrospective medical record review was conducted with 101 electronic medical records of adult trauma patients treated over 1 year. Patients were identified to have experienced massive bleeding if their medical record contained 1 of 4 indicators: (1) transfusion of uncrossmatched blood; (2) tranexamic acid administration; (3) transfusion of 4 or more units of packed red blood cells (PRBCs) in 1 hr; and/or (4) transfusion of 10 or more units of PRBCs in 24 hr. While 58 patients experienced massive bleeding, only 16 (28%) were managed using the MTP. Although the non-MTP group received fewer transfused blood products due to higher initial and 24-hr hemoglobin levels, more deaths occurred in this group than in the MTP group. The recommendations were to (1) establish well-defined criteria for MTP activation based on the 4 indicators of massive bleeding and (2) regularly evaluate the use and efficacy of the MTP to ensure positive patient outcomes.

Evaluation Tool for Assessing a Newly Implemented Massive Transfusion Protocol

Exsanguination requires massive blood product replacement and termination of the bleeding source to prevent hemorrhagic shock and death. Massive transfusion protocols (MTPs) are algorithms that allow the health care team to quickly stabilize the bleeding patient and guide blood product administration. However, no national MTP guidelines or a standardized evaluation tool exist for collecting and reporting MTP-related data. The purpose of this article is to describe an original MTP evaluation tool, how it was used, barriers encountered, and a framework for reporting the MTP evaluation data. The evidence-based Broxton MTP Evaluation Tool was developed to evaluate the use of a newly implemented MTP via a retrospective review of electronic medical records (EMRs). Although the instrument itself worked well, barriers were encountered while reviewing the EMRs for the MTP evaluation. These barriers included no institutional entity was charged with tracking MTP activations, no searchable database was established to collect data concerning the MTP-activated patients, and no standard location in the EMR was designated for documenting the MTP activation. When devising protocols such as an MTP, a priori strategies should be developed for its implementation, documentation, and evaluation. Research is needed to determine best practices for evaluating an MTP to ensure positive patient outcomes with this protocol.

Efficacy of a massive transfusion protocol for hemorrhagic trauma resuscitation

OBJECTIVES

New paradigm shifts in trauma resuscitation recommend that early reconstitution of whole blood ratios with massive transfusion protocols (MTP) may be associated with improved survival. We performed a preliminary study on the efficacy of MTP at an urban, Level 1 trauma center and its impact on resuscitation goals.

METHODS

A case-control study was performed on consecutive critically-ill trauma patients over the course of 1 year. The trauma captain designated patients as either MTP activation (cases) or routine care without MTP (controls) in matched, non-randomized fashion. Primary outcomes were: time to initial transfusion; number of total units of packed red blood cells (pRBC) and fresh frozen plasma (FFP) transfused; and ratio of pRBC to fresh frozen plasma (pRBC:FFP). Secondary outcomes were in-hospital mortality, and length of stay.

RESULTS

Out of 226 patients screened, we analyzed 58 patients meeting study criteria (32 MTP, 26 non-MTP). Study characteristics for the MTP and non-MTP groups were similar except age (34.0 vs. 45.85 years, p=0.015). MTP patients received blood products more expeditiously (41.7 minutes vs. 62.1 minutes, p=0.10), with more pRBC (5.19 vs 3.08 units, p=0.05), more FFP (0.19 vs 0.08 units, p<0.01), and had larger pRBC:FFP ratios (1.90 vs 0.52, p<0.01). Secondary outcomes did not differ significantly but the MTP group was associated with a trend for decreased hospital length of stay (p=0.08).

CONCLUSIONS

MTP resulted in clinically significant improvements in transfusion times and volumes. Further larger and randomized studies are warranted to validate these findings to optimize MTP protocols.

Ionised calcium levels in major trauma patients who received blood en route to a military medical treatment facility

BACKGROUND

Hypocalcaemia is a common metabolic derangement in critically ill patients. Blood transfusion can also contribute to depleted calcium levels. The aims of this study were to identify the incidence of hypocalcaemia in military trauma patients receiving blood products en route to a deployed hospital facility and to determine if intravenous calcium, given during the prehospital phase, has an effect on admission calcium levels.

METHODS

This was a retrospective review of patients transported by the UK Medical Emergency Response Team in Afghanistan between January 2010 and December 2014 who were treated with blood products in the prehospital setting. Total units of blood products administered, basic demographics, Injury Severity Score and trauma type were collected. Ionised serum calcium levels on admission to hospital were compared between those who received blood products without prehospital intravenous calcium supplemental therapy (non-treatment) and patients who were treated with 10 mL of intravenous calcium chloride (10%) concurrently with blood products (treatment).

RESULTS

The study included 297 patients; 237 did not receive calcium and 60 did. The incidence of hypocalcaemia in the non-treatment group was 70.0% (n=166) compared with 28.3% (n=17) in the treatment group. Serum calcium levels were significantly different between the groups (1.03 mmol/L vs 1.25 mmol/L, difference 0.22 mmol/L, 95% CI 0.15 to 0.27). In the non-treatment group, 26.6% (n=63) had calcium levels within the normal range compared with 41.7% (n=25) in those who received calcium. There was a dose response of calcium level to blood products with a significant decrease in calcium levels as the volume of blood products increased.

CONCLUSION

Trauma patients who received blood products were at high risk of hypocalcaemia. Aggressive management of these patients with intravenous calcium during transfusion may be required.

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

BACKGROUND

Admission hypocalcemia predicts both massive transfusion and mortality in severely injured patients. However, the effect of calcium derangements during resuscitation remains unexplored. We hypothesize that any hypocalcemia or hypercalcemia (either primary or from overcorrection) in the first 24 hours after severe injury is associated with increased mortality.

METHODS

All patients at our institution with massive transfusion protocol activation from January 2013 through December 2014 were identified. Patients transferred from another hospital, those not transfused, those with no ionized calcium (Ca) measured, and those who expired in the trauma bay were excluded. Hypocalcemia and hypercalcemia were defined as any level outside the normal range of Ca at our institution (1-1.25 mmol/L). Receiver operator curve analysis was also used to further examine significant thresholds for both hypocalcemia and hypercalcemia. Hospital mortality was compared between groups. Secondary outcomes included advanced cardiovascular life support, damage control surgery, ventilator days, and intensive care unit days.

RESULTS

The massive transfusion protocol was activated for 77 patients of whom 36 were excluded leaving 41 for analysis. Hypocalcemia occurred in 35 (85%) patients and hypercalcemia occurred in 9 (22%). Mortality was no different in hypocalcemia versus no hypocalcemia (29% vs 0%; P = .13) but was greater in hypercalcemia versus no hypercalcemia (78% vs 9%; P < .01). Receiver operator curve analysis identified inflection points in mortality outside a Ca range of 0.84 to 1.30 mmol/L. Using these extreme values, 15 (37%) had hypocalcemia with a 60% mortality (vs 4%; P < .01) and 9 (22%) had hypercalcemia with a 78% mortality (vs 9%; P < .01). Patients with extreme hypocalcemia and hypercalcemia also received more red blood cells, plasma, platelets, and calcium repletion.

CONCLUSIONS

Hypocalcemia and hypercalcemia occur commonly during the initial resuscitation of severely injured patients. Mild hypocalcemia may be tolerable, but more extreme hypocalcemia and any hypercalcemia should be avoided. Further assessment to define best practice for calcium management during resuscitation is warranted.

Whole blood transfusion closest to the point-of-injury during French remote military operations

To improve the survival of combat casualties, interest in the earliest resort to whole blood (WB) transfusion on the battlefield has been emphasized. Providing volume, coagulation factors, plasma, and oxygenation capacity, WB appears actually as an ideal product severe trauma management. Whole blood can be collected in advance and stored for subsequent use, or can be drawn directly on the battlefield, once a soldier is wounded, from an uninjured companion and immediately transfused.Such concepts require a great control of risks at each step, especially regarding ABO mismatches, and transfusion-transmitted diseases. We present here the "warm and fresh" WB field transfusion program implemented among the French armed forces. We focus on the followed strategies to make it applicable on the battlefield, even during special operations and remote settings, and safe for recipients as well as for donors.

Critical Care for the Obstetrician and Gynecologist: Obstetric Hemorrhage and Disseminated Intravascular Coagulopathy

Obstetric hemorrhage accounts for 5% all deliveries in the United States and accounts for high maternal morbidity and mortality. Many hemorrhages are secondary to uterine atony and are quickly ameliorated with appropriate uterotonic use. However, for a subset of cases, severe hemorrhage may require advanced resuscitative techniques, and innovative procedural and surgical techniques. This article guides a provider through such a resuscitation.

What's in the Box? the Effectiveness of a Low-Volume Massive Transfusion Protocol

Transfusion ratios approaching 1:1:1 of packed red blood cells (PRBCs) to fresh frozen plasma (FFP) to platelet have been shown to improve outcomes in trauma. There is little data available to describe in what quantity that ratio should be delivered. We hypothesized that lowering the total volume of products delivered in each protocol round would not adversely affect outcomes in the bleeding trauma patient. A retrospective review of 9732 trauma patients admitted to a rural Level I trauma center over a 3-year period was performed. Patients who received a massive transfusion (greater than 10 units of blood product transfused in the first 24 hours), between January 2012 and April 2015 were identified as the study cohort. In May of 2014, our institution switched from a massive transfusion protocol (MTP) that included 6 PRBCs:6 FFP:1 platelet to a lower volume massive transfusion protocol (LVMTP) that included 4 PRBG4 FFP:1 platelet. Data collected included patient demographics, vital signs, and outcomes. A total of 131 patients met study criteria. MTP was activated on 65 per cent of patients (57/88), receiving a massive transfusion during the 28 months before implementation of the new protocol. In contrast, LVMTP was activated in 100 per cent of patients (43/43) receiving a massive transfusion in the 12 months after implementation of the new protocol. There was no significant difference in age (36.6 vs 37.2, P = 0.87), injury severity score (29.8 vs 32.3, P = 0.45), or per cent penetrating mechanism (43.9 vs 37.2%, P = 0.503) when comparing MTP to LVMTP. In addition, there was no significant difference in mortality (47.4 vs 41.9%, P = 0.584), lengths of stay (13.5 vs 17.1, P = 0.258), or vent days (6.4 vs 8.2, P = 0.236) when comparing MTP to LVMTP. A LVMTP is safe and effective for the resuscitation of the trauma patient.

Hypocalcemia in trauma patients receiving massive transfusion

BACKGROUND

Massive transfusion protocol (MTP) is increasingly used in civilian trauma resuscitation. Calcium is vital for coagulation, but hypocalcemia commonly occurs during massive transfusion due to citrate and serum calcium chelation. This study was conducted to determine the incidence of hypocalcemia and severe hypocalcemia in trauma patients who receive massive transfusion and to compare characteristics of patients with severe versus nonsevere hypocalcemia.

MATERIALS AND METHODS

This was a retrospective study of trauma patients who received massive transfusion between January 2009 and November 2013. The primary outcome was the incidence of hypocalcemia (ionized calcium [iCa] < 1.12 mmol/L) and severe hypocalcemia (iCa < 0.90 mmol/L). Secondary outcomes included calcium monitoring, calcium replacement, and correction of coagulopathy.

RESULTS

There were 156 patients included; 152 (97%) experienced hypocalcemia, and 111 (71%) had severe hypocalcemia. Patients were stratified into iCa ≥ 0.90 (n = 45) and iCa < 0.90 (n = 111). There were no differences in demographics or baseline laboratories except the severe hypocalcemia group had higher baseline activated partial thromboplastin time (29.7 [23.7-50.9] versus 25.8 [22.3-35.9], P = 0.003), higher lactic acid (5.8 [4.1-9.8] versus 4.0 [3.1-7.8], P = 0.019), lower platelets (176 [108-237] versus 208 [169-272], P = 0.003), and lower pH (7.14 [6.98-7.28] versus 7.23 [7.14-7.33], P = 0.019). Mortality was higher in the severe hypocalcemia group (49% versus 24%, P = 0.007). Patients in the iCa < 0.90 group received more blood products (34 [23-58] versus 22 [18-30] units, P < 0.001), and calcium chloride (4 [2-7] versus 3 [1-4] g, P = 0.002), but there was no difference in duration of MTP or final iCa. Neither group reached a median iCa > 1.12.

CONCLUSIONS

Hypocalcemia is common during MTP, and vigilant monitoring is warranted. Research is needed to effectively manage hypocalcemia during massive transfusion.

Damage Control and the Open Abdomen: Challenges for the Nonsurgical Intensivist

BACKGROUND

As strategies in acute care surgery focus on damage control to restore physiology, intensivists spanning all disciplines care for an increasing number of patients requiring massive transfusion, temporary abdominal closures, and their sequelae.

OBJECTIVE

To equip the nonsurgical intensivist with evidence-based management principles for patients with an open abdomen after damage control surgery.

DATA SOURCE

Search of PubMed database and manual review of bibliographies from selected articles.

DATA SYNTHESIS AND CONCLUSIONS

Temporary abdominal closure improves outcomes in patients with abdominal compartment syndrome, hemorrhagic shock, and intra-abdominal sepsis but creates new challenges with electrolyte derangement, hypovolemia, malnutrition, enteric fistulas, and loss of abdominal wall domain. Intensive care of such patients mandates attention to resuscitation, sepsis control, and expedient abdominal closure.

A prospective, randomized trial of intravenous hydroxocobalamin versus whole blood transfusion compared to no treatment for Class III hemorrhagic shock resuscitation in a prehospital swine model

OBJECTIVES

The objective was to compare systolic blood pressure (sBP) over time in swine that have had 30% of their blood volume removed (Class III shock) and treated with intravenous (IV) whole blood or IV hydroxocobalamin, compared to nontreated control animals.

METHODS

Thirty swine (45 to 55 kg) were anesthetized, intubated, and instrumented with continuous femoral and pulmonary artery pressure monitoring. Animals were hemorrhaged a total of 20 mL/kg over a 20-minute period. Five minutes after hemorrhage, animals were randomly assigned to receive 150 mg/kg IV hydroxocobalamin solubilized in 180 mL of saline, 500 mL of whole blood, or no treatment. Animals were monitored for 60 minutes thereafter. A sample size of 10 animals per group was determined based on a power of 80% and an alpha of 0.05 to detect an effect size of at least a 0.25 difference (>1 standard deviation) in mean sBP between groups. sBP values were analyzed using repeated-measures analysis of variance (RANOVA). Secondary outcome data were analyzed using repeated-measures multivariate analysis of variance (RMANOVA).

RESULTS

There were no significant differences between hemodynamic parameters of IV hydroxocobalamin versus whole blood versus control group at baseline (MANOVA; Wilks' lambda; p = 0.868) or immediately posthemorrhage (mean sBP = 47 mm Hg vs. 41 mm Hg vs. 37 mm Hg; mean arterial pressure = 39 mm Hg vs. 28 mm Hg vs. 34 mm Hg; mean serum lactate = 1.2 mmol/L vs. 1.4 mmol/L vs. 1.4 mmol/L; MANOVA; Wilks' lambda; p = 0.348). The outcome RANOVA model detected a significant difference by time between groups (p < 0.001). Specifically, 10 minutes after treatment, treated animals showed a significant increase in mean sBP compared to nontreated animals (mean sBP = 76.3 mm Hg vs. 85.7 mm Hg vs. 51.1 mm Hg; p < 0.001). RMANOVA modeling of the secondary data detected a significant difference in mean arterial pressure, heart rate, and serum lactate (p < 0.001). Similar to sBP, 10 minutes after treatment, treated animals showed a significant increase in mean arterial pressure compared to nontreated animals (mean arterial pressure = 67.7 mm Hg vs. 61.4 mm Hg vs. 40.5 mm Hg). By 10 minutes, mean heart rate was significantly slower in treated animals compared to nontreated animals (mean heart rate = 97.3 beats/min vs. 95.2 beats/min vs. 129.5 beats/min; p < 0.05). Serum lactate, an early predictor of shock, continued to rise in the control group, whereas it did not in treated animals. Thirty minutes after treatment, serum lactate values of treated animals were significantly lower compared to nontreated animals (p < 0.05). This trend continued throughout the 60-minute observation period such that 60-minute values for lactate were 1.4 mmol/L versus 1.1 mmol/L versus 3.8 mmol/L. IV hydroxocobalamin produced a statistically significant increase in systemic vascular resistance compared to control, but not whole blood, with a concomitant decrease in cardiac output.

CONCLUSIONS

Intravenous hydroxocobalamin was more effective than no treatment and as effective as whole blood transfusion, in reversing hypotension and inhibiting rises in serum lactate in this prehospital, controlled, Class III swine hemorrhage model.

Tissue ischemia microdialysis assessments following severe traumatic haemorrhagic shock: lactate/pyruvate ratio as a new resuscitation end point?

BACKGROUND

Intensive care of severe trauma patients focuses on the treatment of haemorrhagic shock. Tissues should be perfused sufficiently with blood and with sufficient oxygen content to ensure adequate tissue oxygen delivery. Tissue metabolism can be monitored by microdialysis, and the lactate/pyruvate ratio (LPR) may be used as a tissue ischemia marker. The aim of this study was to determine the adequate cardiac output and haemoglobin levels that avoid tissue ischemia.

METHODS

Adult patients with serious traumatic haemorrhagic shock were enrolled in this prospective observational study. The primary observed parameters included haemoglobin, cardiac output, central venous saturation, arterial lactate and the tissue lactate/pyruvate ratio.

RESULTS

Forty-eight patients were analysed. The average age of the patients was 39.8 ± 16.7, and the average ISS was 43.4 ± 12.2. Hb < 70 g/l was associated with pathologic arterial lactate, ScvO2 and LPR. Tissue ischemia (i.e., LPR over 25) developed when CI ≤ 3.2 l/min/m(2) and Hb between 70 and 90 g/l were observed. Severe tissue ischemia events were recorded when the Hb dropped below 70 g/l and CI was 3.2-4.8 l/min/m(2). CI ≥ 4.8 l/min/m(2) was not found to be connected with tissue ischemia, even when Hb ≤ 70 g/l.

CONCLUSION

LPR could be a useful marker to manage traumatic haemorrhagic shock therapies. In initial traumatic haemorrhagic shock treatments, it may be better to maintain CI ≥ 3.2 l/min/m(2) and Hb ≥ 70 g/l to avoid tissue ischemia. LPR could also be a useful transfusion trigger when it may demonstrate ischemia onset due to low local DO2 and early reveal low/no tissue perfusion.

Hemorrhage and coagulopathy in the critically ill

Bleeding is the second leading cause of death after trauma. Initial care of the patient with hemorrhage focuses on restoring circulating blood volume and reversing coagulopathy. Trauma and injury can initiate the coagulation cascade. Patients with massive bleeding should be resuscitated with goal-directed therapy. Hemostatic resuscitation in conjunction with ratio-based transfusion and massive transfusion protocols should be utilized while awaiting hemorrhage control. The military initiated massive transfusion protocols in the battlefield. We discuss the coagulation cascade, recent recommendations of goal-directed therapy, massive transfusion protocols, fixed ratios, and the future of transfusion medicine.

Whole spontaneous spinal epidural hematoma

A 26-year-old male who had no underlying disease, including coagulopathy, underwent thoracotomy and bleeding control due to hemothorax. On the fifth postoperative day, paralysis of both lower limbs occurred. Urgent spine magnetic resonance imaging showed a massive anterior spinal epidural hematoma from C2 to L1 level with different signal intensities, which was suspected to be staged hemorrhage. Hematoma evacuation with decompressive laminectomy was performed. The patient's neurologic deterioration was recovered immediately, and he was discharged without neurological deficits. A drug history of naftazone, which could induce a drug-induced platelet dysfunction, was revealed retrospectively. To our knowledge, this is the first report of whole spontaneous spinal epidural hematoma in a young patient, with a history of hemorrhoid medication.

Blood product transfusions and reactions

Blood product transfusions are an essential component of the practice of emergency medicine. From acute traumatic hemorrhage to chronic blood loss necessitating transfusion for symptomatic anemia, familiarity with individual blood products and their indications for transfusion is an essential tool for every emergency physician (EP). Although the focus of this article is primarily on the transfusion of red blood cells, many of the concepts are applicable to the transfusion of all blood products. EPs must be fully familiar with both the individual blood components and the potential reactions and complications of these transfusions.

Pelvic fractures presenting with haemodynamic instability: treatment options and outcomes

The management of trauma patients with haemodynamic instability and an unstable pelvic fracture is an issue of vivid debate in "trauma community". A multidisciplinary approach needs to be instituted regarding the required diagnostic and therapeutic measures. Control of haemorrhage is the first priority. Arterial embolization and/or preperitoneal pelvic packing follow the provisional skeletal pelvic stabilization. The sequence of these interventions still remains an issue of controversy. It needs to be determined on an institutional basis based on the available local resources such as angiography suite and whole-body CT scan and the expertise of the treating surgical team. Despite the fact that recent advances in diagnostic modalities and trauma care systems have improved the overall outcome of patients with pelvic fractures, the early mortality associated with high-energy pelvic injuries presenting with haemodynamic instability remains high. Any suspected injured person with pelvic ring injury should automatically be taken to a level one-trauma centre where all the facilities required are in place for these patients to survive.