Goal-directed hemostatic resuscitation for massively bleeding patients: the Copenhagen concept

Resuscitation and Care in the Trauma Bay

Start balanced resuscitation early (pre-hospital if possible), either in the form of whole blood or 1:1:1 ratio. Minimize resuscitation with crystalloid to minimize patient morbidity and mortality. Trauma-induced coagulopathy can be largely avoided with the use of balanced resuscitation, permissive hypotension, and minimized time to hemostasis. Using protocolized "triggers" for massive and ultramassive transfusion will assist in minimizing delays in transfusion of products, achieving balanced ratios, and avoiding trauma induced coagulopathy. Once "audible" bleeding has been addressed, further blood product resuscitation and adjunct replacement should be guided by viscoelastic testing. Early transfusion of whole blood can reduce patient morbidity, mortality, decreases donor exposure, and reduces nursing logistics during transfusions. Adjuncts to resuscitation should be guided by laboratory testing and carefully developed, institution-specific guidelines. These include empiric calcium replacement, tranexamic acid (or other anti-fibrinolytics), and fibrinogen supplementation.

The Choice between Plasma-Based Common Coagulation Tests and Cell-Based Viscoelastic Tests in Monitoring Hemostatic Competence: Not an either-or Proposition

There has been a significant interest in the last decade in the use of viscoelastic tests (VETs) to determine the hemostatic competence of bleeding patients. Previously, common coagulation tests (CCTs) such as the prothrombin time (PT) and partial thromboplastin time (PTT) were used to assist in the guidance of blood component and hemostatic adjunctive therapy for these patients. However, the experience of decades of VET use in liver failure with transplantation, cardiac surgery, and trauma has now spread to obstetrical hemorrhage and congenital and acquired coagulopathies. Since CCTs measure only 5 to 10% of the lifespan of a clot, these assays have been found to be of limited use for acute surgical and medical conditions, whereby rapid results are required. However, there are medical indications for the PT/PTT that cannot be supplanted by VETs. Therefore, the choice of whether to use a CCT or a VET to guide blood component therapy or hemostatic adjunctive therapy may often require consideration of both methodologies. In this review, we provide examples of the relative indications for CCTs and VETs in monitoring hemostatic competence of bleeding patients.

Viscoelastic Hemostatic Assays for Orthopedic Trauma and Elective Procedures

The application of viscoelastic hemostatic assays (VHAs) (e.g., thromboelastography (TEG) and rotational thromboelastometry (ROTEM)) in orthopedics is in its relative infancy when compared with other surgical fields. Fortunately, several recent studies describe the emerging use of VHAs to quickly and reliably analyze the real-time coagulation and fibrinolytic status in both orthopedic trauma and elective orthopedic surgery. Trauma-induced coagulopathy—a spectrum of abnormal coagulation phenotypes including clotting factor depletion, inadequate thrombin generation, platelet dysfunction, and dysregulated fibrinolysis—remains a potentially fatal complication in severely injured and/or hemorrhaging patients whose timely diagnosis and management are aided by the use of VHAs. Furthermore, VHAs are an invaluable compliment to common coagulation tests by facilitating the detection of hypercoagulable states commonly associated with orthopedic injury and postoperative status. The use of VHAs to identify hypercoagulability allows for an accurate venous thromboembolism (VTE) risk assessment and monitoring of VTE prophylaxis. Until now, the data have been insufficient to permit an individualized approach with regard to dosing and duration for VTE thromboprophylaxis. By incorporating VHAs into routine practice, orthopedic surgeons will be better equipped to diagnose and treat the complete spectrum of coagulation abnormalities faced by orthopedic patients. This work serves as an educational primer and up-to-date review of the current literature on the use of VHAs in orthopedic surgery.

Intervening on the Storage Time of RBC Units and its Effects on Adverse Recipient Outcomes using Real-World Data

Emulating hypothetical randomized trials using large real-world data may be well suited to address the issues of prior RBC transfusion RCTs.

Our study suggests that transfusing RBC units stored for >1 or 2 weeks increases recipient mortality.

Randomized controlled trials (RCTs) have found no evidence that the storage time of transfused red blood cell (RBC) units affects recipient survival. However, inherent difficulties in conducting RBC transfusion RCTs have prompted critique of their design, analyses, and interpretation. Here, we address these issues by emulating hypothetical randomized trials using large real-world data to further clarify the adverse effects of storage time. We estimated the comparative effect of transfusing exclusively older vs fresher RBC units on the primary outcome of death, and the secondary composite end point of thromboembolic events, or death, using inverse probability weighting. Thresholds were defined as 1, 2, 3, and 4 weeks of storage. A large Danish blood transfusion database from the period 2008 to 2018 comprising >900 000 transfusion events defined the observational data. A total of 89 799 patients receiving >340 000 RBC transfusions during 28 days of follow-up met the eligibility criteria. Treatment with RBC units exclusively fresher than 1, 2, 3, and 4 weeks of storage was found to decrease the 28-day recipient mortality with 2.44 percentage points (pp) (0.86 pp, 4.02 pp), 1.93 pp (0.85 pp, 3.02 pp), 1.06 pp (–0.20 pp, 2.33 pp), and −0.26 pp (–1.78 pp, 1.25 pp) compared with transfusing exclusively older RBC units, respectively. The 28-day risk differences for the composite end point were similar. This study suggests that transfusing exclusively older RBC units stored for >1 or 2 weeks increases the 28-day recipient mortality and risk of thromboembolism or death compared with transfusing fresher RBC units.

Real-life experiences with goal-directed prohemostatic therapy with fibrinogen concentrate, prothrombin complex concentrate, and recombinant factor VIIa: a retrospective study of 287 consecutive patients

The Danish Capital Region Blood Bank operates a 24/7 on-call service staffed with physicians specialized in hemostatic management to guide clinicians in hemostatic resuscitation, including administration of prohemostatic therapy (PHT). The outcome of patients who receive PHT as part of hemostatic resuscitation remains unanswered. The objective of this study was therefore to investigate clinical outcome of patients receiving PHT managed by the on-call service. We identified 287 patients who received PHT during 2015-16, of which 161 (59%) received fibrinogen concentrate (FC), 111 (39%) received prothrombin complex concentrate (PCC), and 15 (5%) received recombinant factor VIIa (rFVIIa) as the first product. Patients were critically ill with a 30-day mortality of 31%. Among FC recipients, cardiothoracic admission, non-trauma, and antithrombotics predicted survival. FC recipients had lower platelet count and thrombelastography clot strengths than the other PHT groups and within the group, these factors predicted mortality. The symptomatic thromboembolic event (TE) rate at 30 days was 5%. For PCC recipients, vitamin K antagonists predicted survival, while rivaroxaban predicted mortality. TE rate was 2%. We did not identify factors associated with survival in the small group of rFVIIa recipients. TE rate was 13%. In summary, trauma and coagulopathy predicted mortality in patients who received FC and our data suggest that optimization of PHT algorithms may be possible. Outcome of patients who received PCC was comparable to results reported elsewhere and its use may be safe in a setting as reported here. Recombinant FVIIa was rarely used but had the highest incidence of arterial thromboembolism.

Viscoelastic Hemostatic Assays: A Primer on Legacy and New Generation Devices

Viscoelastic hemostatic assay (VHAs) are whole blood point-of-care tests that have become an essential method for assaying hemostatic competence in liver transplantation, cardiac surgery, and most recently, trauma surgery involving hemorrhagic shock. It has taken more than three-quarters of a century of research and clinical application for this technology to become mainstream in these three clinical areas. Within the last decade, the cup and pin legacy devices, such as thromboelastography (TEG^® 5000) and rotational thromboelastometry (ROTEM^® delta), have been supplanted not only by cartridge systems (TEG^® 6S and ROTEM^® sigma), but also by more portable point-of-care bedside testing iterations of these legacy devices (e.g., Sonoclot^®, Quantra^®, and ClotPro^®). Here, the legacy and new generation VHAs are compared on the basis of their unique hemostatic parameters that define contributions of coagulation factors, fibrinogen/fibrin, platelets, and clot lysis as related to the lifespan of a clot. In conclusion, we offer a brief discussion on the meteoric adoption of VHAs across the medical and surgical specialties to address COVID-19-associated coagulopathy.

Hemorrhagic Resuscitation Guided by Viscoelastography in Far-Forward Combat and Austere Civilian Environments: Goal-Directed Whole-Blood and Blood-Component Therapy Far from the Trauma Center

Modern approaches to resuscitation seek to bring patient interventions as close as possible to the initial trauma. In recent decades, fresh or cold-stored whole blood has gained widespread support in multiple settings as the best first agent in resuscitation after massive blood loss. However, whole blood is not a panacea, and while current guidelines promote continued resuscitation with fixed ratios of blood products, the debate about the optimal resuscitation strategy-especially in austere or challenging environments-is by no means settled. In this narrative review, we give a brief history of military resuscitation and how whole blood became the mainstay of initial resuscitation. We then outline the principles of viscoelastic hemostatic assays as well as their adoption for providing goal-directed blood-component therapy in trauma centers. After summarizing the nascent research on the strengths and limitations of viscoelastic platforms in challenging environmental conditions, we conclude with our vision of how these platforms can be deployed in far-forward combat and austere civilian environments to maximize survival.

Managing patients on direct factor Xa inhibitors with rapid thrombelastography

The use of direct factor Xa inhibitors rivaroxaban and apixaban (XABANs) has rapidly increased; however, there is no validated test available to monitor the effect on hemostasis. This study aims to assess how hemostatic management based on the Rapid Thromboelastography (R-TEG) variable activated clotting time (ACT) of XABAN patients with ongoing bleedings or in need for acute surgical intervention, affected patient outcome. A total of 343 XABAN patients were included in the main analysis together with 50 healthy volunteers to validate the reference value for ACT. An ACT >120 s (s) was defined as having XABAN-induced coagulopathy. Sixty-five percent of the XABAN patients presented with R-TEG ACT within the normal reference. Patients with XABAN-induced coagulopathy had a significantly increased risk of severe bleeding. Significantly more patients with extra-cerebral bleeding (ECB) and ACT above 120 s were transfused with five red blood cell (RBC) units or more compared to patients with ACT at 120 s or below (17% vs. 3%, p <.05). Significantly more XABAN-patients with ACT above 120 s received pro-hemostatic intervention with prothrombin complex concentrate (PCC) when compared to those with ACT at 120 s or below (ECB: 2% vs. 8%, p =.03, intracranial hemorrhage: 25% vs. 68%, p <.00). Patients who received PCC had a higher 30- and 90-day mortality compared to the rest of the cohort (16% vs. 6%, p = .02 and 21% vs. 7%, p =.00). Patients with XABAN-induced coagulopathy as evaluated by R-TEG ACT presented with more severe bleeding and higher transfusion requirements when compared to those with ACT in the normal range. This suggests that R-TEG ACT measurement in XABAN patients with active hemorrhage or in need for acute surgery may be of clinical value.

Assessment of post-trauma complications in eight million trauma cases over a decade in the USA

BACKGROUND

Trauma is associated with a significant risk of post-trauma complications (PTCs). These include thromboembolic events, strokes, infections, and failure of organ systems (eg, kidney failure). Although care of the trauma patient has evolved during the last decade, whether this has resulted in a reduction in specific PTCs is unknown. We hypothesize that the incidence of PTCs has been decreasing during a 10-year period from 2007 to 2017.

METHODS

This is a descriptive study of trauma patients originating from level 1, 2, 3, and 4 trauma centers in the USA, obtained via the Trauma Quality Improvement Program (TQIP) database from 2007 to 2017. PTCs documented throughout the time frame were extracted along with demographic variables. Multiple regression modeling was used to associate admission year with PTCs, while controlling for age, gender, Glasgow Coma Scale score, and Injury Severity Score.

RESULTS

Data from 8 720 026 trauma patients were extracted from the TQIP database. A total of 366 768 patients experienced one or more PTCs. There was a general decrease in the incidence of PTCs during the study period, with the overall incidence dropping from 7.0% in 2007 to 2.8% in 2017. Multiple regression identified a slight decrease in incidence in all PTCs, although deep surgical site infection (SSI), deep venous thrombosis (DVT), and stroke incidences increased when controlled for confounders.

DISCUSSION

Overall the incidence of PTCs dropped during the 10-year study period, although deep SSI, DVT, stroke, and cardiac arrest increased during the study period. Better risk prediction tools, enabling a precision medicine approach, are warranted to identify at-risk patients.

LEVEL OF EVIDENCE

III.

Whole Blood, Fixed Ratio, or Goal-Directed Blood Component Therapy for the Initial Resuscitation of Severely Hemorrhaging Trauma Patients: A Narrative Review

This narrative review explores the pathophysiology, geographic variation, and historical developments underlying the selection of fixed ratio versus whole blood resuscitation for hemorrhaging trauma patients. We also detail a physiologically driven and goal-directed alternative to fixed ratio and whole blood, whereby viscoelastic testing guides the administration of blood components and factor concentrates to the severely bleeding trauma patient. The major studies of each resuscitation method are highlighted, and upcoming comparative trials are detailed.

Resuscitation of Endotheliopathy and Bleeding in Thoracic Aortic Dissections: The VIPER-OCTA Randomized Clinical Pilot Trial

BACKGROUND:

Thoracic aorta dissection is an acute critical condition associated with shock-induced endotheliopathy, coagulopathy, massive bleeding, and significant morbidity and mortality. Our aim was to compare the effect of coagulation support with solvent/detergent-treated pooled plasma (OctaplasLG) versus standard fresh frozen plasma (FFP) on glycocalyx and endothelial injury, bleeding, and transfusion requirements.

METHODS:

Investigator-initiated, single-center, blinded, randomized clinical pilot trial of adult patients undergoing emergency surgery for thoracic aorta dissection. Patients were randomized to receive OctaplasLG or standard FFP as coagulation factor replacement related to bleeding. The primary outcome was glycocalyx and endothelial injury. Other outcomes included bleeding, transfusions and prohemostatics at 24 hours, organ failure, length of stay in the intensive care unit and in the hospital, safety, and mortality at 30 and 90 days.

RESULTS:

Fifty-seven patients were included to obtain 44 evaluable on the primary outcome. The OctaplasLG group displayed significantly reduced damage to the endothelial glycocalyx (syndecan-1) and reduced endothelial tight junction injury (sVE-cadherin) compared to standard FFP. In the OctaplasLG group compared to the standard FFP, days on ventilator (1 day [interquartile range, 0–1] vs 2 days [1–3]; P = .013), bleeding during surgery (2150 [1600–3087] vs 2750 [2130–6875]; P = .046), 24-hour total transfusion and platelet transfusion volume (3975 mL [2640–6828 mL] vs 6220 mL [4210–10,245 mL]; P = .040, and 1400 mL [1050–2625 mL] vs 2450 mL [1400–3500 mL]; P = .027), and goal-directed use of prohemostatics (7/23 [30.4%] vs 13/21 [61.9%]; P = .036) were all significantly lower. Among the 57 patients randomized, 30-day mortality was 20.7% (6/29) in the OctaplasLG group and 25% (7/28) in the standard FFP group (P = .760). No safety concern was raised.

CONCLUSIONS:

In this randomized, clinical pilot trial of patients undergoing emergency surgery for thoracic aorta dissections, we found that OctaplasLG reduced glycocalyx and endothelial injury, reduced bleeding, transfusions, use of prohemostatics, and time on ventilator after surgery compared to standard FFP. An adequately powered multicenter trial is warranted to confirm the clinical importance of the findings.

The anticoagulant effect of therapeutic levels of dabigatran in atrial fibrillation evaluated by thrombelastography (TEG®), Hemoclot Thrombin Inhibitor (HTI) assay and Ecarin Clotting Time (ECT)

Monitoring the effect of dabigatran (Pradaxa^®) is challenging. The aim of this study was to evaluate if thrombelastography reaction time (TEG^® R) could detect the anticoagulant effect of dabigatran showing a correlation between TEG^® R, Hemoclot Thrombin Inhibitor (HTI) assay and Ecarin Clotting Time (ECT) in patients with non-valvular atrial fibrillation (NVAF). Blood samples from 35 AF patients receiving either 110 mg (n 19) or 150 mg (n 16) dabigatran twice daily were analyzed with TEG^®, HTI and ECT 2-3 h after dabigatran intake. All patients had prolonged TEG^® R. The patients receiving dabigatran 110 mg ×2 had a TEG^® R mean 14.2 min (range 9.1-25), a mean dabigatran concentration measured by HTI of 268.5 ng/mL (range 54-837 ng/mL) and by ECT of 355.7 ng/mL (range 40-1020 ng/mL). The corresponding numbers for patients receiving dabigatran 150 mg ×2 were TEG^® R mean of 12.5 min (range 9.2-23.2 min), mean dabigatran concentration of 179.2 ng/mL by HTI (range 26-687 ng/mL) and by ECT 225.1 ng/mL (range 42-1020 ng/mL). The two dosage groups had comparable anticoagulation demonstrated by equally prolonged TEG^® R (p = .909), HTI (p = .707) and ECT (p = .567). No difference in creatinine levels in the two dosage groups was observed (p = .204) though patients with dabigatran concentration >400 ng/mL had significantly higher creatinine levels (p = .001). Large individual variation of the anticoagulant response was observed. Some patients had TEG^® R values up to three times upper normal limit with immediate risk of bleeding. Our data indicate that TEG^® R reflected dabigatran levels in NVAF patients and that TEG^® R correlated to HTI and ECT.

Clot dynamics and mortality: The MA-R ratio

INTRODUCTION

The coagulopathy of trauma, illustrated by a short R-time, is common and well understood. The physiology behind this may be early thrombin burst with rapid clot formation. Rapid consumption of fibrinogen, however, may result in weak clot and substrate depletion, resulting in low MA. While these characteristics are interesting, utilizing thromboelastography (TEG) to identify those at risk of subsequent bleeding diathesis, especially in those who do not demonstrate early signs of physiologic derangement, is challenging. We have developed a novel ratio utilizing TEG values to describe patients at specific risk of traumatic coagulopathy. The purpose of this study was to create a single TEG value, which would reflect both the hypercoagulability and hypocoagulability of TIC. We hypothesized that this ratio, at admission, would be indicative of TIC and predictive of both blood product transfusion volumes and subsequent mortality.

METHODS

Patients admitted via the highest activation criteria at one of two Level I trauma centers were included if they received at least 1 unit of packed red blood cells in the first 24 hours of admission. The admission TEG was collected, and a ratio was calculated by dividing the MA by the R-time (MA-R). MA-R quartiles were developed, and multivariable logistic regression was utilized to determine odds of mortality.

RESULTS

Three hundred thirty patients with admission TEG were included. In all patients, median age was 35 years (interquartile range, 25-54 years), Injury Severity Score (ISS) was 20 (interquartile range, 13-29), 76% were male, and 43% had penetrating trauma. The MA-R groups were based on quartiles. Multivariable analysis, controlling for mechanism of injury, ISS, and admission pH, showed that increasing ratios were associated with decreased odds of death. The lowest MA-R ratios were also significantly associated with higher ISS, higher rates of blunt injury, and higher plasma utilization without a significant difference in packed red blood cell administration.

CONCLUSIONS

Patients with the lowest MA-R ratios demonstrated the highest mortality rates. This novel ratio may prove highly useful to predict at-risk patients early, when other physiologic indicators are absent. The mechanism driving this finding may rest in fibrinogen depletion, resulting in weak clot. Patients with low MA-R ratios may benefit from earlier resuscitation with cryoprecipitate, rather than the traditional use of plasma found in current massive transfusion protocols.

LEVELS OF EVIDENCE

Prognostic study, Level I.

Damage Control Resuscitation for Catastrophic Bleeding

The timely recognition of shock secondary to hemorrhage from severe facial trauma or as a complication of complex oral and maxillofacial surgery presents formidable challenges. Specific hemostatic disorders are induced by hemorrhage and several extreme homeostatic imbalances may appear during or after resuscitation. Damage control resuscitation has evolved from massive transfusion to a more complex therapeutic paradigm that includes hemodynamic resuscitation, hemostatic resuscitation, and homeostatic resuscitation. Definitive control of bleeding is the principal objective of any comprehensive resuscitation scheme for hemorrhagic shock.

Haemotherapy algorithm for the management of trauma-induced coagulopathy: an Australian perspective

PURPOSE OF REVIEW

Recent advances in the understanding of the pathophysiological processes associated with traumatic haemorrhage and trauma-induced coagulopathy have resulted in improved outcomes for seriously injured trauma patients. However, a significant number of trauma patients still die from haemorrhage. This article reviews the various transfusion strategies utilized in the management of traumatic haemorrhage and describes the major haemorrhage protocol (MHP) strategy employed by an Australian trauma centre.

RECENT FINDINGS

Few topics in trauma resuscitation incite as much debate and controversy as to what constitutes the 'ideal' MHP. There is a widespread geographical and institutional variation in clinical practice. Three strategies are commonly utilized; fixed ratio major haemorrhage protocol (FRMHP), viscoelastic haemostatic assay (VHA)-guided MHP and hybrid MHP. The majority of trauma centres utilize an FRMHP and there is high-level evidence to support the use of high blood product ratios. It can be argued that the FRMHP is too simplistic to be applied to all trauma patients and that the use of VHA-guided MHP with predominant factor concentrate transfusion can allow rapid individualized interventions. In between these two strategies is a hybrid MHP, combining early FRMHP with subsequent VHA-guided transfusion.

SUMMARY

There are advantages and disadvantages to each of the various MHP strategies and the evidence base to support one above another with any certainty is lacking at this time. One strategy cannot be considered superior to the other and the choice of MHP is dependent on interpretation of the current literature and local institutional logistical considerations. A number of exciting studies are currently underway that will certainly increase the evidence base and help inform clinical practice.

Research progress of acute coagulopathy of trauma-shock

Acute coagulopathy of trauma-shock (ACoTS) occurs in 25% of patients with severe trauma in the early phase, and the mortality of those patients is four-fold higher than patients without coagulopathy. The pathophysiology of this complicated phenomenon has been focused on in recent years. Tissue injury and hypoperfusion, activated protein C and Complements play important roles in the early phase after trauma. While the use of blood products, hypothermia, acidosis and inflammation are the main mechanism in late phase. Supplementing coagulation factors and platelets to improve ACoTS are inefficient. Only positive resuscitation from shock and improving tissue hypoperfusion have expected benefits.

Bleeding and damage control surgery

PURPOSE OF REVIEW

Bleeding is still a major cause of death in trauma patients. Damage control surgery is a strategy that aims to control bleeding and avoid secondary contamination of the cavity. This article checks the principles and indications of damage control surgery, bleeding management, and the role of the anesthesiologist in trauma context. The efficient treatment of severe trauma and exsanguinated patients includes a surgical approach to the patient performed as quickly as possible. Volemic resuscitation, hemostatic transfusion, prevention and/or treatment of coagulopathy, hypothermia, and acidosis are strategies that reduce bleeding, as well as permissive hypotension.

RECENT FINDINGS

Specialized literature shows us that the adoption of all of these principles along with reduced surgical time has led to a broader concept called damage control resuscitation.

SUMMARY

Damage control resuscitation is a treatment strategy in which the recovery of physiological variables is initially prioritized over anatomical variables and can be required in severe trauma patients.

Mortality in trauma patients with active arterial bleeding managed by embolization or surgical packing: An observational cohort study of 66 patients

Objective:

Exsanguination due to coagulopathy and vascular injury is a common cause of death among trauma patients. Arterial injury can be treated either by angiography and embolization or by explorative laparotomy and surgical packing. The purpose of this study was to compare 30-day mortality and blood product consumption in trauma patients with active arterial haemorrhage in the abdominal and/or pelvic region treated with either angiography and embolization or explorative laparotomy and surgical packing.

Material and Methods:

From January 1^st 2006 to December 31^st 2011 2,173 patients with an ISS of >9 were admitted to the Trauma Centre of Copenhagen University Hospital, Rigshospitalet, Denmark. Of these, 66 patients met the inclusion criteria: age above 15 years and active arterial haemorrhage from the abdominal and/or pelvic region verified by a CT scan at admission. Gender, age, initial oxygen saturation, pulse rate and respiratory rate, mechanism of injury, ISS, Probability of Survival, treatment modality, 30-day mortality and number and type of blood products applied were retrieved from the TARN database, patient records and the Danish Civil Registration System.

Results:

Thirty-one patients received angiography and embolization, and 35 patients underwent exploratory laparotomy and surgical packing. Gender, age, initial oxygen saturation, pulse rate and respiratory rate, ISS and Probability of Survival were comparable in the two groups.

Conclusion:

A significant increased risk of 30-day mortality (P = 0.04) was found in patients with active bleeding treated with explorative laparotomy and surgical packing compared to angiography and embolization when data was adjusted for age and ISS. No statistical significant difference (P > 0.05) was found in number of transfused blood products applied in the two groups of patients.

Transfusion therapy in paediatric trauma patients: a review of the literature

Haemorrhage is a leading cause of death in paediatric trauma patients. Predefined massive transfusion protocols (MTP) have the potential to significantly reduce mortality by treating haemorrhagic shock and coagulopathy, in adhering to the principles of haemostatic resuscitation with rapid administration of balanced ratios of packed red blood cells (RBC), fresh frozen plasma (FFP) and platelets (PLT).

Because of their substantial physiological reserve, initial vital signs may not be good predictors of early haemorrhage in paediatric patients. Determining the triggers for MTP activation in paediatric trauma patients is challenging, and the optimal blood product ratio that will increase survival in massively bleeding paediatric trauma patients has yet to be determined. To date, only a few small descriptive studies and case reports have investigated the use of predefined MTP in paediatric trauma patients.

MTP with increased FFP or PLT to RBC ratios combined with viscoelastic haemostatic assay (VHA) guided haemostatic resuscitation have not yet been tested in paediatric populations but based on results from adult trauma patients, this therapeutic approach seems promising.

Considering the high prevalence of early coagulopathy in paediatric trauma patients, immediate identification and implementation of VHA-directed treatment of traumatic coagulopathy could ensure faster haemostasis and thereby, potentially, reduce bleeding as well as the total transfusion requirements and further improve outcome in paediatric trauma patients. Prospective randomized trials investigating this therapeutic approach in paediatric trauma patients are highly warranted.

Goal-directed transfusion protocol via thrombelastography in patients with abdominal trauma: a retrospective study

INTRODUCTION

The optimal transfusion protocol remains unknown in the trauma setting. This retrospective cohort study aimed to determine if goal-directed transfusion protocol based on standard thrombelastography (TEG) is feasible and beneficial in patients with abdominal trauma.

METHODS

Sixty adult patients with abdominal trauma who received 2 or more units of red blood cell transfusion within 24 hours of admission were studied. Patients managed with goal-directed transfusion protocol via TEG (goal-directed group) were compared to patients admitted before utilization of the protocol (control group).

RESULTS

There were 29 patients in the goal-directed group and 31 in the control group. Baseline parameters were similar except for higher admission systolic blood pressure in the goal-directed group than the control group (121.8 ± 23.1 mmHg vs 102.7 ± 26.5 mmHg, p < 0.01). At 24 h, patients in the goal-directed group had shorter aPTT compared to patients in the control group (39.2 ± 16.3 s vs 58.6 ± 36.6 s, p = 0.044). Administration of total blood products at 24 h appeared to be fewer in the goal-directed group than the control group (10.2 [7.0-43.1]U vs 14.8 [8.3-37.6]U, p = 0.28), but this was not statistically significant. Subgroup analysis including patients with ISS ≥16 showed that patients in the goal-directed group had significantly fewer consumption of total blood products than patients in the control group (7[6.1, 47.0]U vs 37.6[14.5, 89.9]U, p = 0.015). No differences were found in mortality at 28d, length of stay in intensive care unit and hospital between the two groups.

CONCLUSIONS

Goal-directed transfusion protocol via standard TEG was achievable in patients with abdominal trauma. The novel protocol, compared to conventional transfusion management, has the potential to decrease blood product utilization and prevent exacerbation of coagulation function.

Management of hemorrhage in trauma

Hemorrhage remains one of the leading causes of trauma-related deaths. Uncontrolled diffuse microvascular bleeding in the course of initial care is common, potentially resulting in exsanguination. Early and aggressive hemostatic intervention increases survival and reduces the incidence of massive transfusion. Thus, timely diagnosis of the underlying coagulation disorders is mandatory. It has been shown that standard coagulation tests do not sufficiently characterize trauma-induced coagulopathy (TIC). This has led to increasing interest in alternatives, such as the viscoelastic test, to diagnose TIC and to provide the basis for a goal-directed hemostatic therapy. The concept of damage control resuscitation (DCR) has been introduced widely in trauma patients with severe bleeding. This strategy addresses important confounders of the coagulation process such as hemodilution, hypothermia, and acidosis; DCR is based on a damage control surgical approach, permissive hypotension, and improvement of hemostatic competence. Many studies have shown benefit in mortality when using high ratios of fresh frozen plasma (FFP) to red blood cells (RBC) as early treatment. However, there is increased awareness that coagulation factor concentrate could be beneficial in the treatment of trauma-induced coagulopathy.

Early Detection of Coagulation Abnormalities in Patients at Nutritional Risk: The Novel Role of Thromboelastography

It is believed that malnutrition is common among hospitalized patients and associated with increased risk of morbidity and mortality. It is unclear if it is more likely to cause coagulation disorders in patients with malnutrition. We, therefore, investigate the feasibility of using thromboelastography (TEG) in early detection of coagulation abnormalities in patients at nutritional risk. Fifty successive adult patients with gastrointestinal disease were prospectively divided into one of two groups according to nutritional risk score (less than 3 and 3 or greater). Blood samples were collected at admission for analysis of standard biochemical parameters, routine coagulation tests, and TEG parameters. A total of 62 per cent of patients (n = 31) were at nutritional risk. Serum concentrations of prealbumin, transferrin, total protein, low-density lipoprotein, high-density lipoprotein, and cholesterol were much lower in the nutritional risk group than in the no-risk group ( P ≤ 0.05). There was no significant difference in routine coagulation tests, whereas most of the TEG parameters showed significant differences between the two groups. The overall coagulation function was worse in patients at nutritional risk than in patients with good nutritional status ( P ≤ 0.01). TEG appears to be more sensitive for the detection of coagulation abnormalities compared with routine coagulation tests in patients at nutritional risk. The phenomenon described in this article should be useful in further studies of patients with malnutrition.

New evidence in trauma resuscitation - is 1:1:1 the answer?

Traumatic injury is a common problem, with over five million worldwide deaths from trauma per year. An estimated 10 to 20% of these deaths are potentially preventable with better control of bleeding. Damage control resuscitation involves early delivery of plasma and platelets as a primary resuscitation approach to minimize trauma-induced coagulopathy. Plasma, red blood cell and platelet ratios of 1:1:1 appear to be the best substitution for fresh whole blood; however, the current literature consists only of survivor bias-prone observational studies.

Low hemorrhage-related mortality in trauma patients in a Level I trauma center employing transfusion packages and early thromboelastography-directed hemostatic resuscitation with plasma and platelets

BACKGROUND

Hemorrhage accounts for most preventable trauma deaths, but still the optimal strategy for hemostatic resuscitation remains debated.

STUDY DESIGN AND METHODS

This was a prospective study of adult trauma patients admitted to a Level I trauma center. Demography, Injury Severity Score (ISS), transfusion therapy, and mortality were registered. Hemostatic resuscitation was based on a massive transfusion protocol encompassing transfusion packages and thromboelastography (TEG)-guided therapy.

RESULTS

A total of 182 patients were included (75% males, median age 43 years, ISS of 17, 92% with blunt trauma). Overall 28-day mortality was 12% with causes of death being exsanguinations (14%), traumatic brain injury (72%, two-thirds expiring within 24 hr), and other (14%). One-fourth, 16 and 15% of the patients, received red blood cells (RBCs), plasma, or platelets (PLTs) within 2 hours from admission and 68, 71, and 75%, respectively, of patients transfused within 24 hours received the respective blood products within the first 2 hours. In patients transfused within 24 hours, the median number of blood products at 2 hours was 5 units of RBCs, 5 units of plasma, and 2 units of PLT concentrates. Nonsurvivors had lower clot strength by kaolin-activated TEG and TEG functional fibrinogen and lower kaolin-tissue factor-activated TEG α-angle and lysis after 30 minutes compared to survivors. None of the TEG variables were independent predictors of massive transfusion or mortality.

CONCLUSION

Three-fourths of the patients transfused with plasma or PLTs within 24 hours received these in the first 2 hours. Hemorrhage caused 14% of the deaths. We introduced transfusion packages and early TEG-directed hemostatic resuscitation at our hospital 10 years ago and this may have contributed to reducing hemorrhagic trauma deaths.

Blood Far Forward--a whole blood research and training program for austere environments

The Blood Far Forward (BFF) research program was established to conduct blood product efficacy and safety studies, donor performance studies, and research on optimal training methods to improve the safety of blood collection and transfusion performed by Norwegian Naval Special Operation Commando soldiers. The use of intravenous fluids for volume replacement during hemorrhagic shock is controversial, but it is currently the standard of care. In the far-forward environment, large volume resuscitation for massive bleeding is a great challenge. Crystalloid and colloid solutions add weight and bulk to the medic's kit, require temperature sensitive storage, and should be warmed before infusion to prevent hypothermia. Excessive use of these solutions causes a dilutional coagulopathy, acidosis, and potentially increased inflammatory injury compared with blood products. Type-specific whole blood from an uninjured combat companion on the other hand is almost always available. It is warm, replaces intravascular volume, and provides oxygen delivery and hemostatic capacity to prevent or treat shock and coagulopathy. Whole blood may be ideal for the resuscitation of combat casualties with hemorrhagic shock. BFF program pilot studies on use of platelet-sparing leukoreduction filters, whole blood transport tolerance, donor performance, and autologous reinfusion of 24-hour ambient temperature stored whole blood have been performed and suggest the feasibility of expanding whole blood use in resuscitation. If successful, the BFF program will change tactics, techniques, and procedures with a new lifesaving capability.

Intraoperative transfusion threshold and tissue oxygenation: a randomised trial

BACKGROUND AND OBJECTIVES

Transfusion with allogeneic red blood cells (RBCs) may be needed to maintain oxygen delivery during major surgery, but the appropriate haemoglobin (Hb) concentration threshold has not been well established. We hypothesised that a higher level of Hb would be associated with improved subcutaneous oxygen tension during major spinal surgery.

MATERIALS AND METHODS

Fifty patients aged 18 years or older scheduled for spinal fusion with instrumentation were included and randomised to receive RBCs at either a Hb concentration of 7·3 g dL(-1) (restrictive group) or a Hb concentration of 8·9 g dL(-1) (liberal group) (Registration no.: H-C-2009-072). Oxygen tension was measured with a polarographic electrode placed subcutaneously over the left deltoid muscle. The primary endpoint was subcutaneous oxygen tension at the time most patients were still undergoing surgery.

RESULTS

Forty-eight patients were included in the intention-to-treat analysis; 25 patients in the restrictive group and 23 patients in the liberal group. The median change in subcutaneous oxygen tension 60 min after surgical incision was -0·79 and -0·75 kPa in the restrictive and the liberal groups, respectively (P = 0·78). No significant difference was found in the lowest subcutaneous oxygen tension; -2·07 vs. -1·95 kPa in the restrictive and the liberal groups, respectively (P = 0·85).

CONCLUSION

A Hb concentration transfusion threshold of 8·9 g dL(-1) was not associated with a higher subcutaneous oxygen tension during major spinal surgery than a threshold of 7·3 g dL(-1), but the trial was compromised by methodological difficulties.

Early and individualized goal-directed therapy for trauma-induced coagulopathy

Severe trauma-related bleeding is associated with high mortality. Standard coagulation tests provide limited information on the underlying coagulation disorder. Whole-blood viscoelastic tests such as rotational thromboelastometry or thrombelastography offer a more comprehensive insight into the coagulation process in trauma. The results are available within minutes and they provide information about the initiation of coagulation, the speed of clot formation, and the quality and stability of the clot. Viscoelastic tests have the potential to guide coagulation therapy according to the actual needs of each patient, reducing the risks of over- or under-transfusion. The concept of early, individualized and goal-directed therapy is explored in this review and the AUVA Trauma Hospital algorithm for managing trauma-induced coagulopathy is presented.

Clinical effectiveness of fresh frozen plasma compared with fibrinogen concentrate: a systematic review

Introduction

Haemostatic therapy in surgical and/or massive trauma patients typically involves transfusion of fresh frozen plasma (FFP). Purified human fibrinogen concentrate may offer an alternative to FFP in some instances. In this systematic review, we investigated the current evidence for the use of FFP and fibrinogen concentrate in the perioperative or massive trauma setting.

Methods

Studies reporting the outcome (blood loss, transfusion requirement, length of stay, survival and plasma fibrinogen level) of FFP or fibrinogen concentrate administration to patients in a perioperative or massive trauma setting were identified in electronic databases (1995 to 2010). Studies were included regardless of type, patient age, sample size or duration of patient follow-up. Studies of patients with congenital clotting factor deficiencies or other haematological disorders were excluded. Studies were assessed for eligibility, and data were extracted and tabulated.

Results

Ninety-one eligible studies (70 FFP and 21 fibrinogen concentrate) reported outcomes of interest. Few were high-quality prospective studies. Evidence for the efficacy of FFP was inconsistent across all assessed outcomes. Overall, FFP showed a positive effect for 28% of outcomes and a negative effect for 22% of outcomes. There was limited evidence that FFP reduced mortality: 50% of outcomes associated FFP with reduced mortality (typically trauma and/or massive bleeding), and 20% were associated with increased mortality (typically surgical and/or nonmassive bleeding). Five studies reported the outcome of fibrinogen concentrate versus a comparator. The evidence was consistently positive (70% of all outcomes), with no negative effects reported (0% of all outcomes). Fibrinogen concentrate was compared directly with FFP in three high-quality studies and was found to be superior for > 50% of outcomes in terms of reducing blood loss, allogeneic transfusion requirements, length of intensive care unit and hospital stay and increasing plasma fibrinogen levels. We found no fibrinogen concentrate comparator studies in patients with haemorrhage due to massive trauma, although efficacy across all assessed outcomes was reported in a number of noncomparator trauma studies.

Conclusions

The weight of evidence does not appear to support the clinical effectiveness of FFP for surgical and/or massive trauma patients and suggests it can be detrimental. Perioperatively, fibrinogen concentrate was generally associated with improved outcome measures, although more high-quality, prospective studies are required before any definitive conclusions can be drawn.

Severity of head injury is associated with increased risk of coagulopathy in combat casualties

BACKGROUND

Traumatic brain injury (TBI) is believed to cause more profound trauma-induced coagulopathy than other injuries of comparable severity. This has not been reported in a large series of combat casualties in which penetrating injuries predominate.

METHODS

Among US combat casualties severely injured in Iraq and Afghanistan who received transfused blood products, isolated TBI patients (head Abbreviated Injury Score [AIS] ≥ 3 and all other AIS <2) were compared with non-TBI patients (head AIS ≤ 2 and any other AIS ≥ 3) to determine the degree to which TBI is associated with coagulopathy as measured by International Normalized Ratio (INR) and to describe characteristics of this population. Stepwise multiple regression analysis was also performed on all US casualties who received transfused blood products to analyze independent predictors of coagulopathy.

RESULTS

We compared 117 patients with isolated TBI and 1,492 patients with non-TBI injuries. Admission INR was significantly higher in TBI patients. There were no differences in age, admission base deficit, systolic or diastolic blood pressure, or hemoglobin. On stepwise multiple regression, base deficit, Glasgow Coma Scale, and head AIS score were independently associated with increased coagulopathy as measured by INR.

CONCLUSION

Patients with severe combat-related trauma and isolated TBI had worse coagulopathy than non-TBI patients. Base deficit, Glasgow Coma Scale, and severity of head injury, as reflected by head AIS, are independently associated with increased coagulopathy as measured by INR.

Reduced clot strength upon admission, evaluated by thrombelastography (TEG), in trauma patients is independently associated with increased 30-day mortality

INTRODUCTION

Exsanguination due to uncontrolled bleeding is the leading cause of potentially preventable deaths among trauma patients. About one third of trauma patients present with coagulopathy on admission, which is associated with increased mortality and will aggravate bleeding in a traumatized patient. Thrombelastographic (TEG) clot strength has previously been shown to predict outcome in critically ill patients. The aim of the present study was to investigate this relation in the trauma setting.

METHODS

A retrospective study of trauma patients with an injury severity qualifying them for inclusion in the European Trauma Audit and Research Network (TARN) and a TEG analysis performed upon arrival at the trauma centre.

RESULTS

Eighty-nine patients were included. The mean Injury Severity Score (ISS) was 21 with a 30-day mortality of 17%. Patients with a reduced clot strength (maximal amplitude < 50 mm) evaluated by TEG, presented with a higher ISS 27 (95% CI, 20-34) vs. 19 (95% CI, 17-22), p = 0.006 than the rest of the cohort. Clot strength correlated with the amount of packed red blood cells (p = 0.01), fresh frozen plasma (p = 0.04) and platelet concentrates (p = 0.03) transfused during the first 24 hours of admission. Patients with low clot strength demonstrated increased 30-day mortality (47% vs. 10%, p < 0.001). By logistic regression analysis reduced clot strength was an independent predictor of increased mortality after adjusting for age and ISS.

CONCLUSION

Low clot strength upon admission is independently associated with increased 30-day mortality in trauma patients and it could be speculated that targeted interventions based on the result of the TEG analysis may improve patient outcome. Prospective randomized trials investigating this potential are highly warranted.

Resuscitation and monitoring in gastrointestinal bleeding

INTRODUCTION

Gastrointestinal bleeding is a common life-threatening problem, causing significant mortality, costs and resource allocation. Its management requires a dynamic multidisciplinary approach that directs diagnostic and therapeutic priorities appropriately.

MATERIALS AND METHODS

Articles published within the past 15 years, related to gastrointestinal bleeding, were reviewed through MEDLINE search, in addition to current guidelines and standards.

RESULTS

Decisions of ICU admission and blood transfusion must be individualized based on the extent of bleeding, hemodynamic profile and comorbidities of the patient and the risk of rebleeding. A secure airway may be required to optimize oxygenation and to prevent aspiration. Doses of induction agents must be reduced due to the changes in volume of distribution. Volume replacement is the cornerstone of resuscitation in profuse bleeding, but nontargeted aggressive fluid resuscitation must be avoided to allow clot formation and to prevent increased bleeding. Decision to give blood transfusion must be based on physiologic triggers rather than a fixed level of hemoglobin. Coagulopathy must be corrected and hypothermia avoided. Need for massive transfusion must be recognized as early as possible, and a 1:1:1 ratio of packed red blood cells, fresh frozen plasma and platelets is recommended to prevent dilutional coagulopathy. Tromboelastography can be used to direct hemostatic resuscitation. Transfusion related lung injury (TRALI) is a significant problem with a mortality rate approaching 40%. Prevention of TRALI is important in patients with gastrointestinal bleeding, especially among patients having end-stage liver disease. Preventive strategies include prestorage leukoreduction, use of male-only or never-pregnant donors and avoidance of long storage times. Management of gastrointestinal bleeding requires delicately tailoring resuscitation to patient needs to avoid nonspecific aggressive resuscitation. "Functional hemodynamic monitoring" requires recognition of indications and limitations of hemodynamic measurements. Dynamic indices like systolic pressure variation are more reliable predictors of volume responsiveness. Noninvasive methods of hemodynamic monitoring and cardiac output measurement need further verification in patients with gastrointestinal bleeding.

CONCLUSIONS

Management of gastrointestinal bleeding requires a dynamic multidisciplinary approach. The mentioned advances in management of hemorrhagic shock must be considered in resuscitation and monitoring of patients with GI bleeding.