Should we increase the ratio of plasma/platelets to red blood cells in massive transfusion: what is the evidence?

Epidemiology and Associated Factors in Transfusion Management in Intensive Care Unit

Severe traumatic injury is one of the main global health issues which annually causes more than 5.8 million worldwide deaths. Uncontrolled haemorrhage is the main avoidable cause of death among severely injured individuals. Management of trauma patients is the greatest challenge in trauma emergency care, and its proper diagnosis and early management of bleeding trauma patients, including blood transfusion, are critical for patient outcomes. Aim: We aimed to describe the epidemiology of transfusion practices in severe trauma patients admitted into Spanish Intensive Care Units. Material and Methods: We performed a multicenter cross-sectional study in 111 Intensive Care Units across Spain. Adult patients with moderate or severe trauma were eligible. Distribution of frequencies was used for qualitative variables and the mean, with its 95% CI, for quantitative variables. Transfusion programmes, the number of transfusions performed, and the blood component transfused were recorded. Demographic variables, mortality rate, hospital stay, SOFA-score and haemoglobin levels were also gathered. Results: We obtained results from 109 patients. The most transfused blood component was packet red blood cells with 93.8% of total transfusions versus 43.8% of platelets and 37.5% of fresh plasma. The main criteria for transfusion were analytical criteria (43.75%), and acute anaemia with shock (18.75%) and without haemodynamic impact (18.75%). Conclusion: Clinical practice shows a ratio of red blood cells, platelets, and Fresh Frozen Plasma (FFP) of 2:1:1. It is necessary to implement Massive Transfusion Protocols as they appear to improve outcomes. Our study suggests that transfusion of RBC, platelets and FFP in a 2:1:1 ratio could be beneficial for trauma patients.

Fresh frozen plasma-to-red blood cell ratio is an independent predictor of blood loss in patients with neuromuscular scoliosis undergoing posterior spinal fusion

PURPOSE

In major trauma with massive blood loss, higher fresh frozen plasma (FFP)-to-red blood cell (RBC) ratios have been associated with improved morbidity and mortality. Our population of patients with neuromuscular scoliosis undergoing posterior spinal fusion (PSF) often lose volumes of blood considered massive, that is, half a blood volume in 3 hours. In this retrospective cohort study, we examined the association of FFP ratio with blood loss in this elective surgical population.

METHODS

Patients with neuromuscular scoliosis undergoing PSF with unit rod fixation were identified from our anesthesia cases database. The patients were divided into two groups: the low FFP group received FFP-to-RBC≤0.5, and the high FFP group received FFP-to-RBC>0.5. After controlling for a false discovery rate in the univariate analysis, a logistic and linear regression was performed to understand the contribution of the significant factors associated with increased blood loss.

RESULTS

Risk estimation showed that patients in the low FFP group were more likely to lose >120% blood volume (odds ratio, 3.87; 95% confidence interval, 2.03-7.38). Linear regression revealed that each unit of increase in FFP-to-RBC ratio was associated with a 27.5% (95% confidence interval, -43.12-11.89) mean reduction in blood volume loss.

CONCLUSIONS

In our retrospective study, we found that FFP-to-RBC ratio was significant independent predictor of blood loss in this group of complex spine patients undergoing PSF. Thus, in patients with neuromuscular scoliosis undergoing posterior spine fusion, use of higher ratio of FFP to RBC may decrease blood loss.

Ten-year evolution of a massive transfusion protocol in a level 1 trauma centre: have outcomes improved?

Background

We aimed to evaluate the evolution and implementation of the massive transfusion protocol (MTP) in an urban level 1 trauma centre. Most data on this topic comes from trauma centres with high exposure to life‐threatening haemorrhage. This study examines the effect of the introduction of an MTP in an Australian level 1 trauma centre.

Methods

A retrospective study of prospectively collected data was performed over a 14‐year period. Three groups of trauma patients, who received more than 10 units of packed red blood cells (PRBC), were compared: a pre‐MTP group (2002–2006), an MTP‐I group (2006–2010) and an MTP‐II group (2010–2016) when the protocol was updated. Key outcomes were mortality, complications and number of blood products transfused.

Results

A total of 168 patients were included: 54 pre‐MTP patients were compared to 47 MTP‐I and 67 MTP‐II patients. In the MTP‐II group, fewer units of PRBC and platelets were administered within the first 24 h: 17 versus 14 (P = 0.01) and 12 versus 8 (P < 0.001), respectively. Less infections were noted in the MTP‐I group: 51.9% versus 31.9% (P = 0.04). No significant differences were found regarding mortality, ventilator days, intensive care unit and total hospital lengths of stay.

Conclusion

Introduction of an MTP‐II in our level 1 civilian trauma centre significantly reduced the amount of PRBC and platelets used during damage control resuscitation. Introduction of the MTP did not directly impact survival or the incidence of complications. Nevertheless, this study reflects the complexity of real‐life medical care in a level 1 civilian trauma centre.

Rapid testing of red blood cells, white blood cells and platelets in intensive care patients using the HemoScreen™ point-of-care analyzer

Acute major bleeding is a condition that can be encountered in critically ill patients and may require rapid transfusions. To evaluate the need for packed red blood cells (RBCs) and platelets (PLTs), it is important to have rapid test results for RBC/hemoglobin and PLTs. Recently, PixCell Medical (Yokneam Ilit, Israel) introduced the HemoScreen™, an automated hematology analyzer. It is a point-of-care device that uses single sample cuvettes and image analysis of RBCs, PLTs and white blood cells (WBCs), performing a five-part differential count. The HemoScreen™ is the first portable differential count instrument that uses image analysis. We compared the RBC, PLT, and WBC test results of the HemoScreen™ with the Sysmex XN device. In the study we analyzed 104 samples from the cardiothoracic, neuro and general intensive care units. The HemoScreen™ technique showed good precision, with total coefficient of variation of 1-2% for RBCs and 3-5% for PLTs. Deming correlations between the HemoScreen and the Sysmex XN instrument analyzer: (WBC_{HemoScreen™} = 1.061* WBC_Sysmex - 0.644; r = 0.995), RBC (RBC_{HemoScreen™} = 0.998* RBC_Sysmex + 0.049; r = 0.993) for WBC and (Platelets_{HemoScreen™} = 1.087* Platelets_Sysmex - 14.80; r = 0.994) for PLT. The HemoScreen™ device provided rapid and accurate test results to evaluate the need for RBC and PLT transfusion. This new technology is promising given that it allows the analysis of WBCs, RBCs, and PLTs further out in the healthcare organization compared with laboratory infrastructure based on traditional cell counters.

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.

Mortality from trauma haemorrhage and opportunities for improvement in transfusion practice

Background

The aim of this study was to describe the prevalence, patterns of blood use and outcomes of major haemorrhage in trauma.

Methods

This was a prospective observational study from 22 hospitals in the UK, including both major trauma centres and smaller trauma units. Eligible patients received at least 4 units of packed red blood cells (PRBCs) in the first 24 h of admission with activation of the massive haemorrhage protocol. Case notes, transfusion charts, blood bank records and copies of prescription/theatre charts were accessed and reviewed centrally. Study outcomes were: use of blood components, critical care during hospital stay, and mortality at 24 h, 30 days and 1 year. Data were used to estimate the national trauma haemorrhage incidence.

Results

A total of 442 patients were identified during a median enrolment interval of 20 (range 7–24) months. Based on this, the national incidence of trauma haemorrhage was estimated to be 83 per million. The median age of patients in the study cohort was 38 years and 73·8 per cent were men. The incidence of major haemorrhage increased markedly in patients aged over 65 years. Thirty-six deaths within 24 h of admission occurred within the first 3 h. At 24 h, 79 patients (17·9 per cent) had died, but mortality continued to rise even after discharge. Patients who received a cumulative ratio of fresh frozen plasma to PRBCs of at least 1 : 2 had lower rates of death than those who received a lower ratio. There were delays in administration of blood. Platelets and cryoprecipitate were either not given, or transfused well after initial resuscitation.

Conclusion

There is a high burden of trauma haemorrhage that affects all age groups. Research is required to understand the reasons for death after the first 24 h and barriers to timely transfusion support.

The impact of increased plasma ratios in massively transfused trauma patients: a prospective analysis

PURPOSE

Transfusion ratios approaching 1:1 FFP:PRBC for trauma resuscitation have become the de facto standard of care. The aim of this study was to prospectively evaluate the effect of increasing ratios of FFP:PRBC transfusion on survival for massively transfused civilian trauma patients as well as determine if time to reach the target ratio had any effect on outcomes.

METHODS

This is a prospective, observational study of all trauma patients requiring a massive transfusion (≥10 PRBC in ≤24 h) at a level 1 trauma center over a 2.5-year period. The ratio of FFP:PRBC was tracked hourly up to 24 h post-initiation of massive transfusion. A logistic regression model was utilized to identify the ideal ratio associated with mortality prediction. A stepwise logistic regression was performed to identify independent predictors of mortality.

RESULTS

The study population was predominantly male (89 %) with a mean age of 34.8 ± 16. On admission, 22 % had a systolic blood pressure ≤90 mmHg, 47 % had a heart rate ≥120, and 25 % had a GCS ≤8. The overall mortality was 33 %. The ratio of FFP:PRBC ≥ 1:1.5 was the second most important independent predictor of mortality for this population (R (2) = 0.59). Survivors had a higher FFP:PRBC ratio at all times during the first 24 h of resuscitation.

CONCLUSIONS

Achieving a ratio of FFP:PRBC ≥ 1:1.5 after the initial 24 h of resuscitation significantly improves survival in massively transfused trauma patients compared to patients that achieved a ratio <1:1.5.

Military-to-civilian translation of battlefield innovations in operative trauma care

BACKGROUND

Historic improvements in operative trauma care have been driven by war. It is unknown whether recent battlefield innovations stemming from conflicts in Iraq/Afghanistan will follow a similar trend. The objective of this study was to survey trauma medical directors (TMDs) at level 1-3 trauma centers across the United States and gauge the extent to which battlefield innovations have shaped civilian practice in 4 key domains of trauma care.

METHODS

Domains were determined by the use of a modified Delphi method based on multiple consultations with an expert physician/surgeon panel: (1) damage control resuscitation (DCR), (2) tourniquet use, (3) use of hemostatic agents, and (4) prehospital interventions, including intraosseous catheter access and needle thoracostomy. A corresponding 47-item electronic anonymous survey was developed/pilot tested before dissemination to all identifiable TMD at level 1-3 trauma centers across the US.

RESULTS

A total of 245 TMDs, representing nearly 40% of trauma centers in the United States, completed and returned the survey. More than half (n = 127; 51.8%) were verified by the American College of Surgeons. TMDs reported high civilian use of DCR: 95.1% of trauma centers had implemented massive transfusion protocols and the majority (67.7%) tended toward 1:1:1 packed red blood cell/fresh-frozen plasma/platelets ratios. For the other 3, mixed adoption corresponded to expressed concerns regarding the extent of concomitant civilian research to support military research and experience. In centers in which policies reflecting battlefield innovations were in use, previous military experience frequently was acknowledged.

CONCLUSION

This national survey of TMDs suggests that military data supporting DCR has altered civilian practice. Perceived relevance in other domains was less clear. Civilian academic efforts are needed to further research and enhance understandings that foster improved trauma surgeon awareness of military-to-civilian translation.

A national common massive transfusion protocol (MTP) is a feasible and advantageous option for centralized blood services and hospitals

BACKGROUND

A common national MTP was jointly implemented in 2011 by the national blood service (Blood Services Group) and seven participating acute hospitals to provide rapid access to transfusion support for massively haemorrhaging patients treated in all acute care hospitals.

METHODS

Through a systematic clinical workflow, blood components are transfused in a ratio of 1:1:1 (pRBC: whole blood-derived platelets: FFP), together with cryoprecipitate for fibrinogen replacement. The composition of components for the MTP is fixed, although operational aspects of the MTP can be adapted by individual hospitals to suit local hospital workflow. The MTP could be activated in support of any patient with critical bleeding and at risk of massive transfusion, including trauma and non-trauma general medical, surgical and obstetric patients.

RESULTS

There were 434 activations of the MTP from October 2011 to October 2013. Thirty-nine per cent were for trauma patients, and 30% were for surgical patients with heavy intra-operative bleeding, with 25% and 6% for patients with gastrointestinal bleeding and peri-partum haemorrhage, respectively. Several hospitals reported reduction in mean time between request and arrival of blood. Mean transfusion ratio achieved was one red cell unit: 0·8 FFP units: 0·8 whole blood-derived platelet units: 0·4 units of cryoprecipitate. Although cryoprecipitate usage more than doubled after introduction of MTP, there was no significant rise in overall red cells, platelet and FFP usage following implementation.

CONCLUSION

This successful collaboration shows that shared transfusion protocols are feasible and potentially advantageous for hospitals sharing a central blood provider.

Transfusion interventions in critical bleeding requiring massive transfusion: a systematic review

Critical bleeding (CB) requiring massive transfusion (MT) can occur in a variety of clinical contexts and is associated with substantial mortality and morbidity. In 2011, the Australian National Blood Authority (NBA) published patient blood management guidelines for CB and MT, which found limited high-quality evidence from which only 2 recommendations could be made. The aim of this systematic review (SR) was to update these guidelines and identify evidence gaps still to be addressed. A comprehensive search was performed for randomized controlled trials (RCTs) and SRs using MeSH index and free text terms in MEDLINE, the Cochrane Library (Issue 11, 2012), EMBASE, CINHAL, PUBMED, and the Transfusion Evidence Library up to July 15, 2014. The evidence was grouped according to 4 questions based on the original guideline relating to transfusion interventions: (1) effect of dose, timing, and ratio of red blood cells (RBCs) to component therapy on patient outcomes; (2) effect of RBC transfusion on patient outcomes; (3) effect of fresh frozen plasma, platelet, cryoprecipitate, fibrinogen concentrate, and prothrombin complex concentrate on patient outcomes; and (4) effect of recombinant activated factor VII (rFVIIa) on patient outcomes. From this search, 19 studies were identified: 6 RCTs and 13 SRs. Two of the RCTs were pilot/feasibility studies, 3 were investigating rFVIIa, and 1 compared restrictive versus liberal RBC transfusion in upper gastrointestinal hemorrhage. Overall, limited new evidence was identified and substantial evidence gaps remain, particularly with regard to the effect of component therapies, including ratio of RBC to component therapies, on patient outcomes. Clinical trials to address these questions are required.

Functional capacity of reconstituted blood in 1:1:1 versus 3:1:1 ratios: a thrombelastometry study

INTRODUCTION

Different transfusion ratio concepts of packed red blood cells (pRBCs), fresh frozen plasma (FFP) and platelets (PLTs) have been implemented in trauma care, but the optimal ratios are still discussed. In this study the hemostatic potential of two predefined ratios was assessed by using an in vitro thrombelastometric approach. Furthermore, age effects of reconstituted blood were analyzed.

METHODS

Whole blood (WB) of voluntary donors was separated into pRBCs, FFP and PLTs and reconstituted into the ratios 1:1:1 and 3:1:1 at day 1, 4, 14, and 24. Standard blood count, electrolytes and coagulation proteins were quantified. The functional coagulation in ratio- and age-specific groups was evaluated using rotational thromboelastometry (ROTEM).

RESULTS

Several coagulation factors reduced significantly in the 3:1:1 ratio and were consistent with increased INR, decelerated clot formation times and A10 (amplitude 10 minutes after clotting time (CT)), flattened α-angle during the EXTEM and diminished MCF for distinct time points during the INTEM, FIBTEM and APTEM assays. With rising age of pRBCs the pH, sodium and potassium reached non-physiological levels.

CONCLUSION

Under standardized in vitro conditions the higher amount of pRBCs in the 3:1:1 ratio diluted coagulation factors significantly on the expense of its functional coagulation capacity as revealed by ROTEM results. Thus, the coagulation functionality of the 1:1:1 ratio predominated.

Not only in trauma patients: hospital-wide implementation of a massive transfusion protocol

OBJECTIVES

To review outcomes of massive transfusion protocol (MTP) activation and determine the impact of MTP implementation on blood bank use.

BACKGROUND

MTP has been established to rapidly provide plasma and packed red blood cells in ratios approaching 1 : 1. Due to availability, MTP has been utilised in non-traumatic haemorrhage despite evidence of benefit in this population. Our hospital-wide implementation of MTP was reviewed for propriety, outcomes and effect on blood bank resources.

METHODS

Retrospective cohort study of patients receiving transfusion after MTP activation from October 2009 to 2011. Underlying medical conditions and baseline medication use were determined. In-hospital and 24-h mortality were compared with evaluation for confounding by Acute Physiology And Chronic Health Evaluation (APACHE) score and duration of MTP activation. Blood product use before and after MTP implementation was reviewed.

RESULTS

MTP activation occurred in 62 trauma and 63 non-trauma patients. Non-trauma patients were older, had more underlying medical conditions and higher APACHE scores compared with trauma patients; 24-h mortality was higher in trauma compared with non-trauma patients (27·4 vs 11·1%, P = 0·02). There was no significant difference of in-hospital mortality. Transfusion ratio did not differ between trauma and non-trauma patients and was not associated with mortality even when MTP activation duration and APACHE score were considered. Hospital-wide blood product use did not change with MTP implementation.

CONCLUSIONS

MTP may be successfully used in trauma and non-trauma settings without significantly impacting overall blood product utilisation. Inclusion of non-trauma patients into prospective studies of resuscitation with blood products is warranted to ensure benefit in these patients.

Damage Control Resuscitation In Trauma

INTRODUCTION

Most preventable trauma deaths are due to uncontrolled hemorrhage.

METHODS

In this article, we briefly describe the pathophysiology of the classical triad of death in trauma, namely, acidosis, hypothermia, and coagulopathy, and then suggest damage control resuscitation strategies to prevent and/or mitigate the effects of each in the bleeding patient.

RESULTS

Damage control resuscitation strategies include body rewarming, restrictive fluid administration, permissive hypotension, balanced blood product administration, and the implementation of massive transfusion protocols.

CONCLUSION

Resuscitating and correcting the coagulopathy of the exsanguinating trauma patient is essential to improve chances of survival.

Major surgical procedures in children with cerebral palsy

There are 3 surgical procedures that patients with cerebral palsy (CP) undergo that may be considered major procedures: femoral osteotomies combined with pelvic osteotomies, spine fusion, and intrathecal baclofen pump implant for the treatment of spasticity. Many complications are known to occur at a higher rate in this population, and some may be avoided with prior awareness of the preoperative pathophysiology of the patient with CP.

Meta-analysis of plasma to red blood cell ratios and mortality in massive blood transfusions for trauma

BACKGROUND

The current military paradigm for blood transfusion in major trauma favours high plasma:RBC ratios. This study aimed determine whether high plasma:red blood cell (RBC) ratios during massive transfusion for trauma decrease mortality, using meta-analysis of contemporaneous groups matched for injury severity score.

METHODS

A systemic review of the published literature for massive blood transfusions in trauma was performed. Patients were categorised into groups based on plasma:RBC transfusion ratios. Meta-analysis was only performed when there were no significant differences in Injury Severity Score (ISS) between ratio groups within studies. The main endpoint was 30-day mortality.

RESULTS

Six observational studies reporting outcomes for 1885 patients were included in this meta-analysis. Five studies were from civilian environments and one from a military setting. Ratio cut-offs at 1:2 were the most commonly reported, demonstrating a survival advantage with higher ratios (OR 0.49, 95% CI 0.31-0.80, p=0.004). Ratios≥1:2 showed a significant reduction in mortality compared to lower ratios (OR 0.56, 95% CI 0.40-0.78, p<0.001). Reducing the cut-off level was still protective (ratios between 1:2.5 and 1:4, OR 0.41), although the confidence interval was wide (0.16-1.00, p=0.05) and data heterogenous (I(2)=78%). Ratios of 1:1 were not proven to confer additional benefit beyond ratios of 1:2 (OR 0.50, 95% CI 0.37-0.68, p<0.001).

CONCLUSIONS

In groups matched for ISS, there was a survival benefit with high plasma:RBC resuscitation ratios. No additional benefits of 1:1 over 1:2 ratios were identified.

How we manage the haematological aspects of major obstetric haemorrhage

Major obstetric haemorrhage (MOH) remains an important medical challenge worldwide, contributing to significant maternal morbidity and mortality. Prompt and appropriate management is essential if we are to improve outcomes and reduce substandard care that may result in adverse consequences. This review describes the current understanding of the pathophysiological aspects of MOH together with the principles of transfusion and haemostatic therapy, with emphasis on a coordinated multidisciplinary approach. We also highlight the current lack of evidence available from randomized controlled trials to inform best practice and the need to prioritize research in this key clinical area.

Implementation of a military-derived damage-control resuscitation strategy in a civilian trauma center decreases acute hypoxia in massively transfused patients

BACKGROUND

Recent military experience supports a paradigm shift in shock resuscitation to damage-control resuscitation (DCR), which emphasizes a plasma-rich and crystalloid-poor approach to resuscitation. The effect of DCR on hypoxia after massive transfusion is unknown. We hypothesized that implementation of a military-derived DCR strategy in a civilian setting would lead to decreased acute hypoxia.

METHODS

A DCR strategy was implemented in 2007. We retrospectively reviewed patients receiving trauma surgeon operative intervention and 10 or more units of packed red blood cells (pRBCs) within 24 hours of injury at an adult Level I trauma center from 2001 to 2010. Demographic data, blood requirements, and PaO₂/FIO₂ ratios were analyzed. To evaluate evolving resuscitation strategies, we fit linear trend models to continuous variables and tested their slopes for statistical significance.

RESULTS

Two hundred sixteen patients met the study criteria, with a mean age of 35 ± 1.1 years and Injury Severity Score (ISS) of 31 ± 9.0. Of the patients, 80% were male, and 52% sustained penetrating injuries. Overall mortality was 32%. Overall mean pRBC and fresh frozen plasma (FFP) units infused in 24 hours were 23.2 ± 1.1 and 18.6 ± 1.1, respectively. Trends for patient age, sex, mechanism of injury, ISS, highest positive end-expiratory pressure, and mean total pRBC transfused over 24 hours were not statistically different from zero. An increasing trend in FFP and platelets transfused during the first 24 hours (p < 0.0001, p = 0.04, respectively) and a decrease in the pRBC/FFP ratio (p < 0.0001) were found. The amount of crystalloid infused during the initial 24 hours decreased with time (p < 0.0001). The lowest PaO₂/FIO₂ ratio recorded during the initial 24 hours increased during the study period (p = 0.01), indicating a statistically significant reduction in hypoxia.

CONCLUSION

A military-derived DCR strategy can be implemented in the civilian setting. DCR led to significant increases in FFP transfusion, decreases in crystalloid use, and acute hypoxia.

Resuscitate early with plasma and platelets or balance blood products gradually: findings from the PROMMTT study

BACKGROUND

The trauma transfusion literature has yet to resolve which is more important for hemorrhaging patients, transfusing plasma and platelets along with red blood cells (RBCs) early in resuscitation or gradually balancing blood product ratios. In a previous report of PROMMTT results, we found (1) plasma and platelet:RBC ratios increased gradually during the 6 hours following admission, and (2) patients achieving ratios more than 1:2 (relative to ratios <1:2) had significantly decreased 6-hour to 24-hour mortality adjusting for baseline and time-varying covariates. To differentiate the association of in-hospital mortality with early plasma or platelet transfusion from that with delayed but gradually balanced ratios, we developed a separate analytic approach.

METHODS

Using PROMMTT data and multilevel logistic regression to adjust for center effects, we related in-hospital mortality to the early receipt of plasma or platelets within the first three to six transfusion units (including RBCs) and 2.5 hours of admission. We adjusted for the same covariates as in our previous report: Injury Severity Score (ISS), age, time and total number of blood product transfusions upon entry to the analysis cohort, and bleeding from the head, chest, or limb.

RESULTS

Of 1,245 PROMMTT patients, 619 were eligible for this analysis. Early plasma was associated with decreased 24-hour and 30-day mortality (adjusted odds ratios of 0.47 [p = 0.009] and 0.44 [p = 0.002], respectively). Too few patients (24) received platelets early for meaningful assessment. In the subgroup of 222 patients receiving no early plasma but continuing transfusions beyond Hour 2.5, achieving gradually balanced plasma and platelet:RBC ratios of 1:2 or greater by Hour 4 was not associated with 30-day mortality (adjusted odds ratios of 0.9 and 1.1, respectively). There were no significant center effects.

CONCLUSION

Plasma transfusion early in resuscitation had a protective association with mortality, whereas delayed but gradually balanced transfusion ratios did not. Further research will require considerably larger numbers of patients receiving platelets early.

Trends in trauma transfusion

Trauma is the leading cause of death in young adults and acute blood loss contributes to a large portion of mortality in the early post-trauma period. The recognition of lethal triad of coagulopathy, hypothermia and acidosis has led to the concepts of damage control surgery and resuscitation. Recent experience with managing polytrauma victims from the Iraq and Afghanistan wars has led to a few significant changes in clinical practice. Simultaneously, transfusion practices in the civilian settings have also been extensively studied retrospectively and prospectively in the last decade. Early treatment of coagulopathy with a high ratio of fresh frozen plasma and platelets to packed red blood cells (FFP:platelet:RBC), prevention and early correction of hypothermia and acidosis, monitoring of hemostasis using point of care tests like thromoboelastometry, use of recombinant activated factor VII, antifibrinolytic drugs like tranexamic acid are just some of the emerging trends. Further studies, especially in the civilian trauma centers, are needed to confirm the lessons learned in the military environment. Identification of patients likely to need massive transfusion followed by immediate preventive and therapeutic interventions to prevent the development of coagulopathy could help in reducing the morbidity and mortality associated with uncontrolled hemorrhage in trauma patients.

Adverse effects of plasma transfusion

Plasma utilization has increased over the past two decades, and there is a growing concern that many plasma transfusions are inappropriate. Plasma transfusion is not without risk, and certain complications are more likely with plasma than other blood components. Clinical and laboratory investigations of the patients suffering reactions after infusion of fresh-frozen plasma (FFP) define the etiology and pathogenesis of the panoply of adverse effects. We review here the pathogenesis, diagnosis, and management of the risks associated with plasma transfusion. Risks commonly associated with FFP include: 1) transfusion-related acute lung injury, 2) transfusion-associated circulatory overload, and 3) allergic and/or anaphylactic reactions. Other less common risks include 1) transmission of infections, 2) febrile nonhemolytic transfusion reactions, 3) red blood cell alloimmunization, and 4) hemolytic transfusion reactions. The effects of pathogen inactivation or reduction methods on these risks are also discussed. Fortunately, a majority of the adverse effects are not lethal and are adequately treated in clinical practice.

What's new in resuscitation strategies for the patient with multiple trauma?

The last decade has seen a sea change in the management of major haemorrhage following traumatic injury. Damage control resuscitation (DCR), a strategy combining the techniques of permissive hypotension, haemostatic resuscitation and damage control surgery has been widely adopted as the preferred method of resuscitation in patients with haemorrhagic shock. The over-riding goals of DCR are to mitigate metabolic acidosis, hypothermia and coagulopathy and stabilise the patient as early as possible in a critical care setting. This narrative review examines the background to these changes in resuscitation practice, discusses the central importance of traumatic coagulopathy in driving these changes particularly in relation to the use of high FFP:RBC ratio and explores methods of predicting, diagnosing and treating the coagulopathy with massive transfusion protocols as well as newer coagulation factor concentrates. We discuss other areas of trauma haemorrhage management including the role of hypertonic saline and interventional radiology. Throughout this review we specifically examine whether the available evidence supports these newer practices.

Clotting factor deficiency in early trauma-associated coagulopathy

BACKGROUND

Coagulopathic bleeding is a leading cause of in-hospital death after injury. A recently proposed transfusion strategy calls for early and aggressive frozen plasma transfusion to bleeding trauma patients, thus addressing trauma-associated coagulopathy (TAC) by transfusing clotting factors (CFs). This strategy may dramatically improve survival of bleeding trauma patients. However, other studies suggest that early TAC occurs by protein C activation and is independent of CF deficiency. This study investigated whether CF deficiency is associated with early TAC.

METHODS

This is a prospective observational cohort study of severely traumatized patients (Injury Severity Score ≥ 16) admitted shortly after injury, receiving minimal fluids and no prehospital blood. Blood was assayed for CF levels, thromboelastography, and routine coagulation tests. Critical CF deficiency was defined as ≤ 30% activity of any CF.

RESULTS

Of 110 patients, 22 (20%) had critical CF deficiency: critically low factor V level was evident in all these patients. International normalized ratio, activated prothrombin time, and, thromboelastography were abnormal in 32%, 36%, and 35%, respectively, of patients with any critically low CF. Patients with critical CF deficiency suffered more severe injuries, were more acidotic, received more blood transfusions, and showed a trend toward higher mortality (32% vs. 18%, p = 0.23). Computational modeling showed coagulopathic patients had pronounced delays and quantitative deficits in generating thrombin.

CONCLUSIONS

Twenty percent of all severely injured patients had critical CF deficiency on admission, particularly of factor V. The observed factor V deficit aligns with current understanding of the mechanisms underlying early TAC. Critical deficiency of factor V impairs thrombin generation and profoundly affects hemostasis.

Change in transfusion practice in massively bleeding patients

This retrospective study evaluates changes in transfusion practice and modified blood product utilisation that occurred over the course of eleven years in patients receiving massive transfusion. The mean number of fresh frozen plasma units transfused increased from 9.0 ± 7.9 in 1998 to 11.3 ± 6.7 in 2008 (p=0.03). The mean number of platelet units increased from 1.9 ± 1.3 in 1998 to 2.6 ± 1.7 in 2008 (p=0.02). The proportion of cryoprecipitate increased from 0.03 ± 0.19 in 1998 to 1.3 ± 1.6 in 2008 (p=0.001). Along with these changes was a trend toward decreased mortality (p=0.05).

Clinical and cellular effects of hypothermia, acidosis and coagulopathy in major injury

BACKGROUND

Hypothermia, acidosis and coagulopathy have long been considered critical combinations after severe injury. The aim of this review was to give a clinical update on this triad in severely injured patients.

METHODS

A non-systematic literature search on hypothermia, acidosis and coagulopathy after major injury was undertaken, with a focus on clinical data from the past 5 years.

RESULTS

Hypothermia (less than 35 °C) is reported in 1·6-13·3 per cent of injured patients. The occurrence of acidosis is difficult to estimate, but usually follows other physiological disturbances. Trauma-induced coagulopathy (TIC) has both endogenous and exogenous components. Endogenous acute traumatic coagulopathy is associated with shock and hypoperfusion. Exogenous effects of dilution from fluid resuscitation and consumption through bleeding and loss of coagulation factors further add to TIC. TIC is present in 10-34 per cent of injured patients, depending on injury severity, acidosis, hypothermia and hypoperfusion. More expedient detection of coagulopathy is needed. Thromboelastography may be a useful point-of-care measurement. Management of TIC is controversial, with conflicting reports on blood component therapy in terms of both outcome and ratios of blood products to other fluids, particularly in the context of civilian trauma.

CONCLUSION

The triad of hypothermia, acidosis and coagulopathy after severe trauma appears to be fairly rare but does carry a poor prognosis. Future research should define modes of early detection and targeted therapy.

The acute management of trauma hemorrhage: a systematic review of randomized controlled trials

Introduction

Worldwide, trauma is a leading cause of death and disability. Haemorrhage is responsible for up to 40% of trauma deaths. Recent strategies to improve mortality rates have focused on optimal methods of early hemorrhage control and correction of coagulopathy. We undertook a systematic review of randomized controlled trials (RCT) which evaluated trauma patients with hemorrhagic shock within the first 24 hours of injury and appraised how the interventions affected three outcomes: bleeding and/or transfusion requirements; correction of trauma induced coagulopathy and mortality.

Methods

Comprehensive searches were performed of MEDLINE, EMBASE, CENTRAL (The Cochrane Library Issue 7, 2010), Current Controlled Trials, ClinicalTrials.gov, the World Health Organization International Clinical Trials Registry Platform (ICTRP) and the National Health Service Blood and Transplant Systematic Review Initiative (NHSBT SRI) RCT Handsearch Database.

Results

A total of 35 RCTs were identified which evaluated a wide range of clinical interventions in trauma hemorrhage. Many of the included studies were of low methodological quality and participant numbers were small. Bleeding outcomes were reported in 32 studies; 7 reported significantly reduced transfusion use following a variety of clinical interventions, but this was not accompanied by improved survival. Minimal information was found on traumatic coagulopathy across the identified RCTs. Overall survival was improved in only three RCTs: two small studies and a large study evaluating the use of tranexamic acid.

Conclusions

Despite 35 RCTs there has been little improvement in outcomes over the last few decades. No clear correlation has been demonstrated between transfusion requirements and mortality. The global trauma community should consider a coordinated and strategic approach to conduct well designed studies with pragmatic endpoints.

Trauma-induced coagulopathy--a review of the systematic reviews: is there sufficient evidence to guide clinical transfusion practice?

Systematic reviews are accepted as a robust and less biased means of appraising and synthesizing results from high-quality studies. This report collated and summarized all the systematic review evidence relating to the diagnosis and management of trauma-related coagulopathy and transfusion, thereby covering the widest possible body of literature. We defined 4 key clinical questions: (1) What are the best methods of predicting and diagnosing trauma-related coagulopathy? (2) Which methods of clinical management correct coagulopathy? (3) Which methods of clinical management correct bleeding? and (4) What are the outcomes of transfusion in trauma? Thirty-seven systematic reviews were identified through searches of MEDLINE (1950-July 2010), EMBASE (1980-July 2010), The Cochrane Library (Issue 7, 2010), National Guidelines Clearing House, National Library for Health Guidelines Finder, and UKBTS SRI Transfusion Evidence Library (www.transfusionevidencelibrary.com). The evidence from the systematic review literature was scanty with many gaps, and we were not able to conclusively answer any of our 4 questions. Much more needs to be understood about how coagulopathy and bleeding in trauma are altered by transfusion practices and, most importantly, whether this translates into improved survival. There is a need for randomized controlled trials to answer these questions. The approach described in this report provides a framework for incorporating new evidence.

The how's and why's of evidence based plasma therapy

Although traditionally fresh frozen plasma (FFP) has been the product of choice for reversing a significant coagulopathy, the modern blood bank will have several different plasma preparations which should all be equally efficacious in reversing a significant coagulopathy or arresting coagulopathic bleeding. Emerging evidence suggests that for a stable patient, transfusing plasma for an INR≤1.5 does not confer a hemostatic benefit while unnecessarily exposing the patient to the risks associated with plasma transfusion. This review will discuss the various plasma products that are available and present some of the current literature on the clinical uses of plasma.