Massive transfusion--evaluation of current clinical practice and outcome in two large teaching hospital trusts in Northern England

Epidemiology of Massive Transfusion - A Common Intervention in Need of a Definition

While massive transfusion (MT) recipients account for a small proportion of all transfused patients, they account for approximately 10% of blood products issued. Furthermore, MT events pose organizational and logistical challenges for health care providers, laboratory and transfusion services. Overall, the majority of MT events are to support major bleeding in surgical patients, trauma and gastrointestinal hemorrhage. The clinical context in which the bleeding event occurred, the number of blood products required, patient age and comorbidities are the most important predictors of outcomes for short- and long-term survival. These data are important to inform blood services, clinicians and health care providers in order to improve care and outcomes for patients with major bleeding. There is no standard accepted definition of MT, with most definitions based on number of blood components administered within a certain time-period or activation of MT protocol. The type of definition used has implications for the clinical characteristics of MT recipients included in epidemiological and interventional studies. In order to understand trends in incidence of MT, variation in blood utilization and patient outcomes, and to harmonize research outcomes, a standard and universally accepted definition of MT is urgently required.

Massive transfusion protocols in nontrauma patients: A systematic review and meta-analysis

BACKGROUND

Massive bleeding is a major cause of death both in trauma and nontrauma patients. In trauma patients, the implementation of massive transfusion protocols (MTP) led to improved outcomes. However, the majority of patients with massive bleeding are nontrauma patients.

OBJECTIVES

To assess if the implementation of MTP in nontrauma patients with massive bleeding leads to improved survival.

DATA SOURCES

National Library of Medicine's Medline database (PubMed).

STUDY ELIGIBILITY CRITERIA

Original research articles in English language investigating MTP in nontrauma patients.

PARTICIPANTS

Nontrauma patients with massive bleeding 18 years or older.

INTERVENTION

Transfusion according to MTP versus off-protocol.

STUDY APPRAISAL AND SYNTHESIS METHODS

Systematic literature review using PubMed. Outcomes assessed were mortality and transfused blood products. Studies that compared mortality of MTP and non-MTP groups were included in meta-analysis using Mantel-Haenszel random effect models.

RESULTS

A total of 252 abstracts were screened. Of these, 12 studies published 2007 to 2017 were found to be relevant to the topic, including 2,475 patients. All studies were retrospective and comprised different patient populations. Most frequent indications for massive transfusion were perioperative, obstetrical and gastrointestinal bleeding, as well as vascular emergencies. Four of the five studies that compared the number of transfused blood products in MTP and non-MTP groups revealed no significant difference. Meta-analysis revealed no significant effect of MTP on the 24-hour mortality (odds ratio 0.42; 95% confidence interval 0.01-16.62; p = 0.65) and a trend toward lower 1-month mortality (odds ratio 0.56; 95% confidence interval 0.30-1.07; p = 0.08).

LIMITATIONS

Heterogeneous patient populations and MTP in the studies included.

CONCLUSION

There is limited evidence that the implementation of MTP may be associated with decreased mortality in nontrauma patients. However, patient characteristics, as well as the indication and definition of MTP were highly heterogeneous in the available studies. Further prospective investigation into this topic is warranted.

LEVEL OF EVIDENCE

Systematic review and meta-analysis, level III.

Early coagulation support protocol: A valid approach in real-life management of major trauma patients. Results from two Italian centres

INTRODUCTION

Early coagulation support (ECS) includes prompt infusion of tranexamic acid, fibrinogen concentrate, and packed red blood cells for initial resuscitation of major trauma patients. The aim of this study was to determine the effects, in terms of blood product consumption, length of stay, and in-hospital mortality, of the ECS protocol, compared to the massive transfusion protocol (MTP) in the treatment of major trauma patients.

PATIENTS AND METHODS

A retrospective analysis was conducted using the registry data of two Italian trauma centres. Adult major trauma patients with, or at risk of, active bleeding who were managed according to the MTP during the years 2011-2012, or the ECS protocol during the years 2013-2014 and were considered at risk of multiple transfusions, were enrolled. The primary endpoint was to determine whether the ECS protocol reduces the use of blood products in the acute management of trauma patients. Secondary endpoints were the outcome measures of length of stay in ICU, length of stay in hospital, and mortality at 24-hours and 28-days after hospital admission.

RESULTS

Among the 518 major trauma patients admitted to the trauma centres during the study period, 235 patients (118 in the pre-ECS period and 117 in the ECS period) matched one of the inclusion criteria and were enrolled in the study. Compared with the pre-ECS period, the ECS period showed a reduction in the average consumption of packed red blood cells (-1.87 units, 95% confidence interval [CI], -2.40, -1.34), platelets (-1.28 units; 95% CI, -1.64, -0.91), and fresh frozen plasma (-1.69; 95% CI, -2.14, -1.25) in the first 24-hours. Furthermore, during the ECS period, we recorded a 10-day reduction in the hospital length of stay (-10 days, 95% CI, -11.6, -8.4) and a non-significant 28-day mortality increase.

CONCLUSIONS

The ECS protocol was effective in reducing blood product consumption compared to the MTP and confirmed the importance of early fibrinogen administration as a strategy of rapid coagulation. This novel approach may be adopted in real-life management of major trauma patients.

Evaluation of clinical coding data to determine causes of critical bleeding in patients receiving massive transfusion: a bi-national, multicentre, cross-sectional study

OBJECTIVES

To evaluate the use of routinely collected data to determine the cause(s) of critical bleeding in patients who receive massive transfusion (MT).

BACKGROUND

Routinely collected data are increasingly being used to describe and evaluate transfusion practice.

MATERIALS/METHODS

Chart reviews were undertaken on 10 randomly selected MT patients at 48 hospitals across Australia and New Zealand to determine the cause(s) of critical bleeding. Diagnosis-related group (DRG) and International Classification of Diseases (ICD) codes were extracted separately and used to assign each patient a cause of critical bleeding. These were compared against chart review using percentage agreement and kappa statistics.

RESULTS

A total of 427 MT patients were included with complete ICD and DRG data for 427 (100%) and 396 (93%), respectively. Good overall agreement was found between chart review and ICD codes (78·3%; κ = 0·74, 95% CI 0·70-0·79) and only fair overall agreement with DRG (51%; κ = 0·45, 95% CI 0·40-0·50). Both ICD and DRG were sensitive and accurate for classifying obstetric haemorrhage patients (98% sensitivity and κ > 0·94). However, compared with the ICD algorithm, DRGs were less sensitive and accurate in classifying bleeding as a result of gastrointestinal haemorrhage (74% vs 8%; κ = 0·75 vs 0·1), trauma (92% vs 62%; κ = 0·78 vs 0·67), cardiac (80% vs 57%; κ = 0·79 vs 0·60) and vascular surgery (64% vs 56%; κ = 0·69 vs 0·65).

CONCLUSION

Algorithms using ICD codes can determine the cause of critical bleeding in patients requiring MT with good to excellent agreement with clinical history. DRG are less suitable to determine critical bleeding causes.

Improving outcomes for hospital patients with critical bleeding requiring massive transfusion: the Australian and New Zealand Massive Transfusion Registry study methodology

Background

The Australian and New Zealand (ANZ) Massive Transfusion (MT) Registry (MTR) has been established to improve the quality of care of patients with critical bleeding (CB) requiring MT (≥ 5 units red blood cells (RBC) over 4 h). The MTR is providing data to: (1) improve the evidence base for transfusion practice by systematically collecting data on transfusion practice and clinical outcomes; (2) monitor variations in practice and provide an opportunity for benchmarking, and feedback on practice/blood product use; (3) inform blood supply planning, inventory management and development of future clinical trials; and (4) measure and enhance translation of evidence into policy and patient blood management guidelines. The MTR commenced in 2011. At each participating site, all eligible patients aged ≥18 years with CB from any clinical context receiving MT are included using a waived consent model. Patient information and clinical coding, transfusion history, and laboratory test results are extracted for each patient’s hospital admission at the episode level.

Results

Thirty-two hospitals have enrolled and 3566 MT patients have been identified across Australia and New Zealand between 2011 and 2015. The majority of CB contexts are surgical, followed by trauma and gastrointestinal haemorrhage. Validation studies have verified that the definition of MT used in the registry correctly identifies 94 % of CB events, and that the median time of transfusion for the majority of fresh products is the ‘product event issue time’ from the hospital blood bank plus 20 min. Data linkage between the MTR and mortality databases in Australia and New Zealand will allow comparisons of risk-adjusted mortality estimates across different bleeding contexts, and between countries. Data extracts will be examined to determine if there are differences in patient outcomes according to transfusion practice. The ratios of blood components (e.g. FFP:RBC) used in different types of critical bleeding will also be investigated.

Conclusions

The MTR is generating data with the potential to have an impact on management and policy decision-making in CB and MT and provide benchmarking and monitoring tools for immediate application.

Calculation of the Residual Blood Volume after Acute, Non-Ongoing Hemorrhage Using Serial Hematocrit Measurements and the Volume of Isotonic Fluid Infused: Theoretical Hypothesis Generating Study

Fluid resuscitation, hemostasis, and transfusion is essential in care of hemorrhagic shock. Although estimation of the residual blood volume is crucial, the standard measuring methods are impractical or unsafe. Vital signs, central venous or pulmonary artery pressures are inaccurate. We hypothesized that the residual blood volume for acute, non-ongoing hemorrhage was calculable using serial hematocrit measurements and the volume of isotonic solution infused. Blood volume is the sum of volumes of red blood cells and plasma. For acute, non-ongoing hemorrhage, red blood cell volume would not change. A certain portion of the isotonic fluid would increase plasma volume. Mathematically, we suggest that the residual blood volume after acute, non-ongoing hemorrhage might be calculated as 0·25N/[(Hct1/Hct2)-1], where Hct1 and Hct2 are the initial and subsequent hematocrits, respectively, and N is the volume of isotonic solution infused. In vivo validation and modification is needed before clinical application of this model.

The use of higher platelet: RBC transfusion ratio in the acute phase of trauma resuscitation: a systematic review

OBJECTIVE

With the recognition of early coagulopathy, trauma resuscitation has shifted toward liberal platelet transfusions. The overall benefit of this strategy remains controversial. Our objective was to compare the effects of a liberal use of platelet (higher platelet:RBC ratios) with a conservative approach (lower ratios) in trauma resuscitation.

DATA SOURCES

We systematically searched Medline, Embase, Web of Science, Biosis, Cochrane Central, and Scopus.

STUDY SELECTION

Two independent reviewers selected randomized controlled trials and observational studies comparing two or more platelet:RBC ratios in trauma resuscitation. We excluded studies investigating the use of whole blood or hemostatic products.

DATA EXTRACTION

Two independent reviewers extracted data and assessed the risk of bias. Primary outcomes were early (in ICU or within 30 d) and late (in hospital or after 30 d) mortality. Secondary outcomes were multiple organ failure, lung injury, and sepsis.

DATA SYNTHESIS

From 6,123 citations, no randomized controlled trials were identified. We included seven observational studies (4,230 patients) addressing confounders through multivariable regression or propensity scores. Heterogeneity of studies precluded meta-analysis. Among the five studies including exclusively patients requiring massive transfusions, four observed a lower mortality with higher ratios. Two studies considering nonmassively bleeding patients observed no benefit of using higher ratios. Two studies evaluated the implementation of a massive transfusion protocol; only one study observed a decrease in mortality with higher ratios. Of the two studies at low risk of survival bias, one study observed a survival benefit. Three studies assessed secondary outcomes. One study observed an increase in multiple organ failure with higher ratios, whereas no study demonstrated an increased risk in lung injury or sepsis.

CONCLUSIONS

There is insufficient evidence to strongly support the use of a precise platelet:RBC ratio for trauma resuscitation, especially in nonmassively bleeding patients. Randomized controlled trials evaluating both the safety and efficacy of liberal platelet transfusions are warranted.

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.

The effect of diabetes on mortality in critically ill patients: a systematic review and meta-analysis

Introduction

Critically ill patients with diabetes are at increased risk for the development of complications, but the impact of diabetes on mortality is unclear. We conducted a systematic review and meta-analysis to determine the effect of diabetes on mortality in critically ill patients, making a distinction between different ICU types.

Methods

We performed an electronic search of MEDLINE and Embase for studies published from May 2005 to May 2010 that reported the mortality of adult ICU patients. Two reviewers independently screened the resultant 3,220 publications for information regarding ICU, in-hospital or 30-day mortality of patients with or without diabetes. The number of deaths among patients with or without diabetes and/or mortality risk associated with diabetes was extracted. When only crude survival data were provided, odds ratios (ORs) and standard errors were calculated. Data were synthesized using inverse variance with ORs as the effect measure. A random effects model was used because of anticipated heterogeneity.

Results

We included 141 studies comprising 12,489,574 patients, including 2,705,624 deaths (21.7%). Of these patients, at least 2,327,178 (18.6%) had diabetes. Overall, no association between the presence of diabetes and mortality risk was found. Analysis by ICU type revealed a significant disadvantage for patients with diabetes for all mortality definitions when admitted to the surgical ICU (ICU mortality: OR [95% confidence interval] 1.48 [1.04 to 2.11]; in-hospital mortality: 1.59 [1.28 to 1.97]; 30-day mortality: 1.62 [1.13 to 2.34]). In medical and mixed ICUs, no effect of diabetes on all outcomes was found. Sensitivity analysis showed that the disadvantage in the diabetic surgical population was attributable to cardiac surgery patients (1.77 [1.45 to 2.16], P < 0.00001) and not to general surgery patients (1.21 [0.96 to 1.53], P = 0.11).

Conclusions

Our meta-analysis shows that diabetes is not associated with increased mortality risk in any ICU population except cardiac surgery patients.

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).

Massive transfusion protocols for patients with substantial hemorrhage

Transfusion medicine for the resuscitation of patients with massive hemorrhage has recently advanced from reactive, supportive treatment with crystalloid and red blood cell therapy to use of standardized massive transfusion protocols (MTPs). Through MTPs, medical facilities are able to standardize the most effective posthemorrhage treatments and execute them rapidly while reducing potential waste of blood products. Damage control resuscitation is an example of an MTP, where patients are (1) allowed more permissive hypotension, (2) spared large volumes of crystalloid/colloid therapy (through low volume resuscitation), and (3) transfused with blood products preemptively using a balanced ratio of plasma and platelets to red blood cells. This focused approach improves the timely availability of blood components during resuscitation. However, the use of MTPs remains controversial. This review describes published experiences with MTPs and illustrates the potential value of several MTPs currently utilized by academic transfusion services.

Review of Current Practice of Blood and Component Transfusion: Critical Issues for the Critically Ill Patient

Major haemorrhage continues to be a leading cause of morbidity and mortality in a number of situations such as trauma, ruptured aneurysms, obstetrics, liver transplantation and gastrointestinal blood loss.1 In modern day clinical practice, clinicians have a range of blood components and specific clotting products at their disposal in the management of such patients. However, recent evidence is driving change in the optimal management of coagulopathy in major haemorrhage. The critically ill patient often exhibits deranged coagulation as assessed by laboratory tests. It is unclear the extent to which this is an epiphenomenon, and to what extent coagulation requires correction prior to either bedside or surgical intervention. There is increasing evidence to suggest that blood and component transfusions carry significant though poorly quantified risks. It is therefore prudent to exercise a selective approach to transfusion, avoiding ‘correction of the numbers’ when the risk of clinically important bleeding is small. In this article, we review current UK practice and evidence for use of blood and its components in the ICU setting. We also appraise more recent concepts such as the new coagulation model, acute coagulopathy of trauma and novel treatment strategies. We will discuss current guidelines and recommendations, and highlight potential areas for future research.

[Immunological blood transfusion safety and selection of red blood cells issued from hospital blood banks]

Allogeneic red blood cells transfusion is always an immunological challenge and the choice of the blood products is crucial for the patient safety. But this choice may be hampered by the quality or the quantity of the available supply. In the end, the lack of transfusion may be more harmful than transfusion. The balance between patients' needs and blood centres supplying is always delicate. The conditions are not the same for all blood groups. Things are easier for the KEL1 phenotype, where the supply must ensure only 92.5% of KEL: -1 red blood cells instead of the 91% expected. More complicated is the situation for group O red blood cells with 47 versus 43%. But the major problem concerns RH: -1 red blood cells, for which the needs reach 20.1 versus 15%. These challenges require a lot of efforts from blood centres staffs to influence blood donors' recruitment and appointments. A justified and carefully selected blood products issuing may be of great help, especially for group O RH: -1 red blood cells. Therefore, hospital blood banks must have ad hoc procedures and a trained staff to put them into practice.