The coagulopathy of massive transfusion

Canadian tertiary care pediatric massive hemorrhage protocols: a survey and comprehensive national review

PURPOSE

Hemorrhage is the leading cause of pediatric death in trauma and cardiac arrest during surgery. Adult studies report improved patient outcomes using massive hemorrhage protocols (MHPs). Little is known about pediatric MHP adoption in Canada.

METHODS

After waived research ethics approval, we conducted a survey of Canadian pediatric tertiary care hospitals to study MHP activations. Transfusion medicine directors provided hospital/patient demographic and MHP activation data. The authors extracted pediatric-specific MHP data from requested policy/procedure documents according to seven predefined MHP domains based on the literature. We also surveyed educational and audit tools. The analysis only included MHPs with pediatric-specific content.

RESULTS

The survey included 18 sites (100% response rate). Only 13/18 hospitals had pediatric-specific MHP content: eight were dedicated pediatric hospitals, two were combined pediatric/obstetrical hospitals, and three were combined pediatric/adult hospitals. Trauma was the most common indication for MHP activation (54%), typically based on a specific blood volume anticipated/transfused over time (10/13 sites). Transport container content was variable. Plasma and platelets were usually not in the first container. There was little emphasis on balanced plasma/platelet to red-blood-cell ratios, and most sites (12/13) rapidly incorporated laboratory-guided goal-directed transfusion. Transfusion thresholds were consistent with recent guidelines. All protocols used tranexamic acid and eight sites used an audit tool.

DISCUSSION/CONCLUSION

Pediatric MHP content was highly variable. Activation demographics suggest underuse in nontrauma settings. Our findings highlight the need for a consensus definition for pediatric massive hemorrhage, a validated pediatric MHP activation tool, and prospective assessment of blood component ratios. A national pediatric MHP activation repository would allow for quality improvement metrics.

Does time to angiography affect the survival of trauma patients with embolization to the pelvis? A retrospective study across trauma centers in the United States

INTRODUCTION

Traumatic pelvic injuries can result in rapid exsanguination. Bleeding control interventions include stabilization, angiography, and possible embolization. Previous studies yielded conflicting results regarding the benefit of a shorter time to embolization.

OBJECTIVES

The aim of this study is to examine the impact of the time to angioembolization on the survival of patients presenting with pelvic injuries using a national database.

MATERIALS AND METHODS

This was an observational retrospective study that used the National Trauma Data Bank 2017 dataset. Adult patients with pelvic injuries and who received angiography with embolization to the pelvis were included. Univariate and bivariate analyses (survival to hospital discharge yes/no) were done. This was followed by a multivariable logistic regression analysis to assess the impact of time to angiography on survival to hospital discharge after adjusting for potential confounders.

RESULTS

A total of 1,057 patients were included. They were predominantly of male gender (69.3 %) with a median age of 50 years (IQR = [31-64]). The mean time to pelvic angiography was 264.0 ± 204.4 min. The overall survival rate at hospital discharge was 72.0 %. Time to angiography was not significantly associated with survival to hospital discharge before and after adjusting for clinically and statistically significant confounders (aOR = 1.000; 95 %CI=[0.999 - 1.001]; p = 0.866).

CONCLUSION

Time to angiography was not associated with survival to hospital discharge of patients with pelvic injuries who required embolization. Further research examining specific patterns of injuries and assessing the impact of early angioembolization is needed.

Determination of reference ranges for the ClotPro® thromboelastometry device in paediatric patients

BACKGROUND

A new thromboelastometry analyser (ClotPro®) was developed with advanced diagnostics. The reference ranges of ClotPro® in children ages 0-16 yr have not been reported.

METHODS

In this prospective study, venous blood samples from 321 patients were obtained from children undergoing elective surgery after induction of anaesthesia. Reference ranges were defined by calculating the 2.5% and 97.5% percentiles for each age group (0-3 months, 4-12 months, 13-24 months, 2-5 yr, 6-10 yr, and 11-16 yr).

RESULTS

Reference ranges of the ClotPro® analyser in all age groups demonstrated significant differences in some parameters between age groups. In the first 3 months of life, a significant shortening of the clotting time (CT) in the extrinsically activated test (EX-test) was observed in children aged 0-3 months compared with children of all older age groups (P<0.001), whereas there were no overall differences in the intrinsically activated test (IN-test). In both assays, the clot amplitude 5 and 10 min after CT (A5, A10 value) was significantly higher in the first year of life compared with children older than 1 yr (EX-test and IN-test A5 and A10, respectively; P<0.001). The strength of fibrin polymerisation (FIB-test) was significantly higher in the first 3 months of life (A5 and A10, P<0.003).

CONCLUSIONS

ClotPro® reference ranges were determined for six paediatric age groups, and show age-dependent differences in specific parameters. These values will be helpful in monitoring haemostasis in paediatric patients and for developing tailored bleeding management protocols.

CLINICAL TRIAL REGISTRATION

NCT04190615.

Physicians' perceptions regarding acute bleeding management: an international mixed qualitative quantitative study

Background

Acute bleeding is an omnipresent challenge for all physicians. Uncontrolled hemorrhage is the most common preventable cause of death after trauma worldwide. In different surgical disciplines, hemorrhage represents an independent risk factor for increased postoperative morbimortality, directly affecting patients’ outcomes. This study asked anesthesiologists about their personal perceived challenges when treating bleeding patients.

Methods

This investigator-initiated, prospective, international, dual-center, mixed qualitative and quantitative study interrogated anesthesiologists about what they found easy and what difficult in treating acutely bleeding patients. Following the template approach for qualitative research, we identified major and minor topics through free inductive coding and word count. In a second step, we derived ten statements from the participants’ answers. Using a field survey, we then asked the participants to rate their level of agreement with the derived statements. We analyzed the answers using one sample Wilcoxon test and the Mann-Whitney test.

Results

We included a total of 84 physicians in the qualitative interrogations and a different group of 42 anesthesiologists in the quantitative part. We identified 11 major topics and 19 associated subtopics. The main topics and the degree of agreement (here as agree or strongly agree) were as follows: “Complexity of the topic” (52.4% agreed to find the topic complex), “Cognitive aids” (92.9% agreed to find them helpful), “Time management” (64.3% agreed to feeling time pressure), “Human factors” (95.2% agreed that human factors are essential), “Resources” (95.2% agreed that resources are essential), “Experience” and “Low frequency of cases” (57.1% agreed to lack practice), “Diagnostic methods” (31.0% agreed that the interpretation of test results is difficult), “Anticoagulation” (85.7% agreed to it being difficult), “Treatment” (81.0% agreed to knowing the first therapeutic steps), and “Nothing”.

Conclusions

Anesthesiologists in two large tertiary care facilities in different parts of the world found coagulation management, especially in anticoagulated patients, complex. We identified the delayed diagnostic test results and their interpretation as challenges. Resources, treatment protocols and human factors such as team communication were perceived to facilitate management. Future studies should explore the challenges in smaller hospitals and other parts of the world and test new technologies addressing the identified difficulties.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12871-021-01269-x.

Targeted cryoprecipitate transfusion in severe traumatic haemorrhage

BACKGROUND

Severe traumatic haemorrhage is the leading cause of death in young adults. Trauma Induced Coagulopathy is a complex and multifactorial phenomenon associated with severe traumatic haemorrhage. Fibrinogen is one of the first coagulation factors to become depleted in TIC and evidence suggests that severely injured trauma patients with hypofibrinogenaemia have poor outcomes. It is postulated that early fibrinogen replacement can improve clinical outcomes. This study investigated cryoprecipitate transfusion in hyopfibrinogeneamic trauma patients.

METHODS

This retrospective, single center, observational study investigated the use of cryoprecipitate in severely injured trauma patients admitted to an Australian Level I Trauma Centre. The primary outcome was time to administration of cryoprecipitate after identification of hypofibrinogenaemia using ROTEM (FIBTEM A5). Data collected included demographics, ISS, laboratory values of coagulation and blood product usage.

RESULTS

71 patients received cryoprecipitate with a median time of 61 minutes [IQR 37-93] from FIBTEM A5 result to initial cryoprecipitate administration. At 24 hours following admission to ED, Clauss Fibrinogen levels increased by 1.30g/L [IQR 0.45-1.85] and FIBTEM A5 assay increased by 8mm [IQR 3.0-11.3]. Changes in both variables were highly significant (p<0.001) and Clauss Fibrinogen versus FIBTEM A5 values showed moderate to strong correlation (R=0.75-0.80).

CONCLUSION

This study demonstrated that early administration of cryoprecipitate was both feasible and efficacious in fibrinogen replacement in severe traumatic haemorrhage. High-level evidence supporting cryoprecipitate or fibrinogen concentrate replacement with regards to efficacy and feasibility is required to guide future clinical practice. This study provided baseline data to inform the design of further clinical trials investigating fibrinogen replacement in traumatic haemorrhage.

Anesthesia for Patients with Extensive Trauma

Trauma anesthesiology is a unique and growing subspecialty. With the growing number of adult and pediatric trauma centers in the United States, a thorough understanding of the early management of severely injured patients with trauma is an important aspect of anesthesia. Trauma anesthesiology requires the ability to adapt to different work environments, including the trauma bay, the operating room, and even the intensive care unit, where a patient room may require conversion to an operating suite for emergencies. This article provides a review of the anesthetic management for patients with extensive trauma, focusing on physiology, pharmacology, and bedside management.

Massive hemorrhage protocol activation in obstetrics: a 5-year quality performance review

BACKGROUND

A structured approach to hemorrhagic emergencies in obstetrics has gained popularity with the implementation of massive hemorrhage protocols. The trauma literature suggests that routine quality reviews should be in place to improve patient outcomes. The aim of this study was to develop quality indicators and assess compliance by the clinical team.

METHODS

A multidisciplinary team set the institutional quality indicators for the massive hemorrhage protocol review. A retrospective review of all obstetrical massive hemorrhage protocol activation events from September 2010 to January 2015 was performed. All protocol events occurred before the creation of the quality indicators. Data were retrieved from patient records.

RESULTS

There were 17 (0.09%) protocol activations for 19 790 deliveries during the study period. All 17 (100%) patients received at least one unit of red blood cells. Overactivation, defined as the transfusion of <2 units of red blood cells, occurred in two cases (12%). Common causes of non-compliance were: 24% (4/17) temperature monitoring, 18% (3/17) lactate measurement, 41% (7/17) arterial blood gas sampling, and 18% (3/17) hemoglobin maintenance within the target range of 55-95 g/L. Admission to intensive care and peripartum hysterectomy occurred in 12 and 5 cases (71% and 29%), respectively.

CONCLUSIONS

Suboptimal compliance was found in multiple areas, which may be attributable to the low frequency of activation of our massive haemorrhage protocol in obstetrics. The quality targets identified in this report can act as a basis for other institutions developing quality indicators to evaluate performance.

Evaluation of massive transfusion protocol practices by type of trauma at a level I trauma center

PURPOSE

To evaluate massive transfusion protocol practices by trauma type at a level I trauma center.

METHODS

A retrospective analysis was performed on a sample of 76 trauma patients with MTP activation between March 2010 and January 2015 at a regional trauma center. Patient demographics, transfusion practices, and clinical outcomes were compared by type of trauma sustained.

RESULTS

Penetrating trauma patients who required MTP activation were significantly younger, had lower injury severity score (ISS), higher probability of survival (POS), decreased mortality, and higher Glasgow Coma scale (GCS) compared to blunt trauma patients. Overall, the mortality rate was 38.16%. The most common injury sustained among blunt trauma patients was head injury (36.21%), whereas the majority of the penetrating trauma patients sustained abdominal injuries (55.56%). Although the admission coagulation parameters and timing of coagulopathy were not significantly different between the two groups of patients, a significantly higher proportion of penetrating trauma patients received high plasma content therapy relative to blunt trauma patients (p < 0.01).

CONCLUSION

Despite the use of the same MTP for all injured patients requiring massive transfusion, significant differences existed between blunt trauma patients and penetrating trauma patients. These differences in transfusion characteristics and outcomes following MTP activation underscore the complexity of implementing MTPs and warrant vigilant transfusion practices to improve outcomes in trauma patients.

Administration of platelets to ruptured abdominal aortic aneurysm patients before open surgery: a prospective, single-blinded, randomised study

BACKGROUND

In patients undergoing open surgery for a ruptured abdominal aortic aneurysm (rAAA), survivors demonstrate a high platelet count, and proactive administration of platelets (and fresh frozen plasma) appears to influence mortality.

OBJECTIVES

This trial investigated the effect of platelets administered before transport to surgery.

METHODS

In a prospective study design, patients were randomised to receive platelets (intervention; n = 61) or no platelets (control; n = 61) before transport to vascular surgery from 11 local hospitals. The study was terminated when one of the vascular surgical centres implemented endovascular repair for rAAA patients.

RESULTS

Thirty days after surgery, mortality was 36% for patients with intervention vs 31% for controls (P = 0·32). Post-operative thrombotic events (14 vs 15; P = 0·69), renal failure (11 vs 10; P = 0·15) and pulmonary insufficiency (34 vs 39; P = 0·15) were similar in the two groups of patients. No adverse reactions to platelet administration were observed. In addition, length of stay in the intensive care unit was unaffected by intervention.

CONCLUSIONS

For patients planned for open repair of a rAAA, we observed no significant effect of early administration of platelets with regard to post-operative complications and stay in the ICU or in hospital and also no significant effect on mortality.

Factors associated with delayed cardiac tamponade after cardiac surgery

Context

Cardiac tamponade (CT) following cardiac surgery is a potentially fatal complication and the cause of surgical reintervention in 0.1%-6% of cases. There are two types of CT: acute, occurring within the first 48 h postoperatively, and subacute or delayed, which occurs more than 48 h postoperatively. The latter does not show specific clinical signs, which makes it more difficult to diagnose. The factors associated with acute CT (aCT) are related to coagulopathy or surgical bleeding, while the variables associated with subacute tamponade have not been well defined.

Aims

The primary objective of this study was to identify the factors associated with the development of subacute CT (sCT).

Settings and Design

This report describes a case (n = 80) and control (n = 160) study nested in a historic cohort made up of adult patients who underwent any type of urgent or elective cardiac surgery in a tertiary cardiovascular hospital. Methods: The occurrence of sCT was defined as the presence of a compatible clinical picture, pericardial effusion and confirmation of cardiac tamponade during the required emergency intervention at any point between 48 hours and 30 days after surgery. All factors potentially related to the development of sCT were taken into account.

Statistical Analysis Used

For the adjusted analysis, a logistical regression was constructed with 55 variables, including pre-, intra-, and post-operative data.

Results

The mortality of patients with sCT was 11% versus 0% in the controls. Five variables were identified as independently and significantly associated with the outcome: pre- or post-operative anticoagulation, reintervention in the first 48 h, surgery other than coronary artery bypass graft, and red blood cell transfusion.

Conclusions

Our study identified five variables associated with sCT and established that this complication has a high mortality rate. These findings may allow the implementation of standardized follow-up measures for patients identified as higher risk, leading to either early detection or prevention.

Diagnostic and therapeutic medical devices for safer blood management in cardiac surgery: systematic reviews, observational studies and randomised controlled trials

Background

Anaemia, coagulopathic bleeding and transfusion are strongly associated with organ failure, sepsis and death following cardiac surgery.

Objective

To evaluate the clinical effectiveness and cost-effectiveness of medical devices used as diagnostic and therapeutic tools for the management of anaemia and bleeding in cardiac surgery.

Methods and results

Workstream 1 – in the COagulation and Platelet laboratory Testing in Cardiac surgery (COPTIC) study we demonstrated that risk assessment using baseline clinical factors predicted bleeding with a high degree of accuracy. The results from point-of-care (POC) platelet aggregometry or viscoelastometry tests or an expanded range of laboratory reference tests for coagulopathy did not improve predictive accuracy beyond that achieved with the clinical risk score alone. The routine use of POC tests was not cost-effective. A systematic review concluded that POC-based algorithms are not clinically effective. We developed two new clinical risk prediction scores for transfusion and bleeding that are available as e-calculators. Workstream 2 – in the PAtient-SPecific Oxygen monitoring to Reduce blood Transfusion during heart surgery (PASPORT) trial and a systematic review we demonstrated that personalised near-infrared spectroscopy-based algorithms for the optimisation of tissue oxygenation, or as indicators for red cell transfusion, were neither clinically effective nor cost-effective. Workstream 3 – in the REDWASH trial we failed to demonstrate a reduction in inflammation or organ injury in recipients of mechanically washed red cells compared with standard (unwashed) red cells.

Limitations

Existing studies evaluating the predictive accuracy or effectiveness of POC tests of coagulopathy or near-infrared spectroscopy were at high risk of bias. Interventions that alter red cell transfusion exposure, a common surrogate outcome in most trials, were not found to be clinically effective.

Conclusions

A systematic assessment of devices in clinical use as blood management adjuncts in cardiac surgery did not demonstrate clinical effectiveness or cost-effectiveness. The contribution of anaemia and coagulopathy to adverse clinical outcomes following cardiac surgery remains poorly understood. Further research to define the pathogenesis of these conditions may lead to more accurate diagnoses, more effective treatments and potentially improved clinical outcomes.

Study registration

Current Controlled Trials ISRCTN20778544 (COPTIC study) and PROSPERO CRD42016033831 (systematic review) (workstream 1); Current Controlled Trials ISRCTN23557269 (PASPORT trial) and PROSPERO CRD4201502769 (systematic review) (workstream 2); and Current Controlled Trials ISRCTN27076315 (REDWASH trial) (workstream 3).

Funding

This project was funded by the National Institute for Health Research (NIHR) Programme Grants for Applied Research programme and will be published in full inProgramme Grants for Applied Research; Vol. 5, No. 17. See the NIHR Journals Library website for further project information.

Viscoelastic testing inside and beyond the operating room

Hemorrhage is a major contributor to morbidity and mortality during the perioperative period. Current methods of diagnosing coagulopathy have various limitations including long laboratory runtimes, lack of information on specific abnormalities of the coagulation cascade, lack of in vivo applicability, and lack of ability to guide the transfusion of blood products. Viscoelastic testing offers a promising solution to many of these problems. The two most-studied systems, thromboelastography (TEG) and rotational thromboelastometry (ROTEM), offer similar graphical and numerical representations of the initiation, formation, and lysis of clot. In systematic reviews on the clinical efficacy of viscoelastic tests, the majority of trials analyzed were in cardiac surgery patients. Reviews of the literature suggest that transfusions of packed red blood cells (pRBC), plasma, and platelets are all decreased in patients whose transfusions were guided by viscoelastic tests rather than by clinical judgement or conventional laboratory tests. Mortality appears to be lower in the viscoelastic testing groups, despite no difference in surgical re-intervention rates and massive transfusion rates. Cost-effectiveness studies also seem to favor viscoelastic testing. Viscoelastic testing has also been investigated in small studies in other clinical contexts, such as sepsis, obstetric hemorrhage, inherited bleeding disorders, perioperative thromboembolism risk assessment, and management of anticoagulation for patients on mechanical circulatory support systems or direct oral anticoagulants (DOACs). While the results are intriguing, no systematic, larger trials have taken place to date. Viscoelastic testing remains a relatively novel method to assess coagulation status, and evidence for its use appears favorable in reducing blood product transfusions, especially in cardiac surgery patients.

Thromboelastography (TEG) or thromboelastometry (ROTEM) to monitor haemostatic treatment versus usual care in adults or children with bleeding

BACKGROUND

Severe bleeding and coagulopathy are serious clinical conditions that are associated with high mortality. Thromboelastography (TEG) and thromboelastometry (ROTEM) are increasingly used to guide transfusion strategy but their roles remain disputed. This review was first published in 2011 and updated in January 2016.

OBJECTIVES

We assessed the benefits and harms of thromboelastography (TEG)-guided or thromboelastometry (ROTEM)-guided transfusion in adults and children with bleeding. We looked at various outcomes, such as overall mortality and bleeding events, conducted subgroup and sensitivity analyses, examined the role of bias, and applied trial sequential analyses (TSAs) to examine the amount of evidence gathered so far.

SEARCH METHODS

In this updated review we identified randomized controlled trials (RCTs) from the following electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 1); MEDLINE; Embase; Science Citation Index Expanded; International Web of Science; CINAHL; LILACS; and the Chinese Biomedical Literature Database (up to 5 January 2016). We contacted trial authors, authors of previous reviews, and manufacturers in the field. The original search was run in October 2010.

SELECTION CRITERIA

We included all RCTs, irrespective of blinding or language, that compared transfusion guided by TEG or ROTEM to transfusion guided by clinical judgement, guided by standard laboratory tests, or a combination. We also included interventional algorithms including both TEG or ROTEM in combination with standard laboratory tests or other devices. The primary analysis included trials on TEG or ROTEM versus any comparator.

DATA COLLECTION AND ANALYSIS

Two review authors independently abstracted data; we resolved any disagreements by discussion. We presented pooled estimates of the intervention effects on dichotomous outcomes as risk ratio (RR) with 95% confidence intervals (CIs). Due to skewed data, meta-analysis was not provided for continuous outcome data. Our primary outcome measure was all-cause mortality. We performed subgroup and sensitivity analyses to assess the effect based on the presence of coagulopathy of a TEG- or ROTEM-guided algorithm, and in adults and children on various clinical and physiological outcomes. We assessed the risk of bias through assessment of trial methodological components and the risk of random error through TSA.

MAIN RESULTS

We included eight new studies (617 participants) in this updated review. In total we included 17 studies (1493 participants). A total of 15 trials provided data for the meta-analyses. We judged only two trials as low risk of bias. The majority of studies included participants undergoing cardiac surgery.We found six ongoing trials but were unable to retrieve any data from them. Compared with transfusion guided by any method, TEG or ROTEM seemed to reduce overall mortality (7.4% versus 3.9%; risk ratio (RR) 0.52, 95% CI 0.28 to 0.95; I(2) = 0%, 8 studies, 717 participants, low quality of evidence) but only eight trials provided data on mortality, and two were zero event trials. Our analyses demonstrated a statistically significant effect of TEG or ROTEM compared to any comparison on the proportion of participants transfused with pooled red blood cells (PRBCs) (RR 0.86, 95% CI 0.79 to 0.94; I(2) = 0%, 10 studies, 832 participants, low quality of evidence), fresh frozen plasma (FFP) (RR 0.57, 95% CI 0.33 to 0.96; I(2) = 86%, 8 studies, 761 participants, low quality of evidence), platelets (RR 0.73, 95% CI 0.60 to 0.88; I(2) = 0%, 10 studies, 832 participants, low quality of evidence), and overall haemostatic transfusion with FFP or platelets (low quality of evidence). Meta-analyses also showed fewer participants with dialysis-dependent renal failure.We found no difference in the proportion needing surgical reinterventions (RR 0.75, 95% CI 0.50 to 1.10; I(2) = 0%, 9 studies, 887 participants, low quality of evidence) and excessive bleeding events or massive transfusion (RR 0.38, 95% CI 0.38 to 1.77; I(2) = 34%, 2 studies, 280 participants, low quality of evidence). The planned subgroup analyses failed to show any significant differences.We graded the quality of evidence as low based on the high risk of bias in the studies, large heterogeneity, low number of events, imprecision, and indirectness. TSA indicates that only 54% of required information size has been reached so far in regards to mortality, while there may be evidence of benefit for transfusion outcomes. Overall, evaluated outcomes were consistent with a benefit in favour of a TEG- or ROTEM-guided transfusion in bleeding patients.

AUTHORS' CONCLUSIONS

There is growing evidence that application of TEG- or ROTEM-guided transfusion strategies may reduce the need for blood products, and improve morbidity in patients with bleeding. However, these results are primarily based on trials of elective cardiac surgery involving cardiopulmonary bypass, and the level of evidence remains low. Further evaluation of TEG- or ROTEM-guided transfusion in acute settings and other patient categories in low risk of bias studies is needed.

Implementation of a management protocol for massive bleeding reduces mortality in non-trauma patients: Results from a single centre audit

OBJECTIVE

To audit the impact upon mortality of a massive bleeding management protocol (MBP) implemented in our center since 2007.

DESIGN

A retrospective, single-center study was carried out. Patients transfused after MBP implementation (2007-2012, Group 2) were compared with a historical cohort (2005-2006, Group 1).

BACKGROUND

Massive bleeding is associated to high mortality rates. Available MBPs are designed for trauma patients, whereas specific recommendations in the medical/surgical settings are scarce.

PATIENTS

After excluding patients who died shortly (<6h) after MBP activation (n=20), a total of 304 were included in the data analysis (68% males, 87% surgical).

INTERVENTIONS

Our MBP featured goal-directed transfusion with early use of adjuvant hemostatic medications.

VARIABLES OF INTEREST

Primary endpoints were 24-h and 30-day mortality. Fresh frozen plasma-to-red blood cells (FFP:RBC) and platelet-to-RBC (PLT:RBC) transfusion ratios, time to first FFP unit and the proactive MBP triggering rate were secondary endpoints.

RESULTS

After MBP implementation (Group 2; n=222), RBC use remained stable, whereas FFP and hemostatic agents increased, when compared with Group 1 (n=82). Increased FFP:RBC ratio (p=0.053) and earlier administration of FFP (p=0.001) were also observed, especially with proactive MBP triggering. Group 2 patients presented lower rates of 24-h (0.5% vs. 7.3%; p=0.002) and 30-day mortality (15.9% vs. 30.2%; p=0.018) - the greatest reduction corresponding to non-surgical patients. Logistic regression showed an independent protective effect of MBP implementation upon 30-day mortality (OR=0.3; 95% CI 0.15-0.61).

CONCLUSIONS

These data suggest that the implementation of a goal-directed MBP for prompt and aggressive management of non-trauma, massive bleeding patients is associated to reduced 24-h and 30-day mortality rates.

Damage control resuscitation

The early recognition and management of hemorrhage shock are among the most difficult tasks challenging the clinician during primary assessment of the acutely bleeding patient. Often with little time, within a chaotic setting, and without sufficient clinical data, a decision must be reached to begin transfusion of blood components in massive amounts. The practice of massive transfusion has advanced considerably and is now a more complete and, arguably, more effective process. This new therapeutic paradigm, referred to as damage control resuscitation (DCR), differs considerably in many important respects from previous management strategies for catastrophic blood loss. We review several important elements of DCR including immediate correction of specific coagulopathies induced by hemorrhage and management of several extreme homeostatic imbalances that may appear in the aftermath of resuscitation. We also emphasize that the foremost objective in managing exsanguinating hemorrhage is always expedient and definitive control of the source of bleeding.

The use of an extracorporeal membrane oxygenation anticoagulation laboratory protocol is associated with decreased blood product use, decreased hemorrhagic complications, and increased circuit life

OBJECTIVES

To determine if a comprehensive extracorporeal membrane oxygenation anticoagulation monitoring protocol results in fewer hemorrhagic complications, reduced blood product usage, and increased circuit life.

DESIGN

In September 2011, we augmented our standard extracorporeal membrane oxygenation laboratory protocol to include anti-factor Xa assays, thromboelastography, and antithrombin measurements. We performed a retrospective chart review to determine outcomes for patients placed on extracorporeal membrane oxygenation prior to and after the initiation of our anticoagulation laboratory protocol.

SETTING

Tertiary care, academic children's hospital.

PATIENTS

All patients who were placed on extracorporeal membrane oxygenation at our institution from January 1, 2007, to September 30, 2013.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

There were 261 extracorporeal membrane oxygenation runs before the initiation of the protocol and 105 extracorporeal membrane oxygenation runs after the initiation of the protocol. There were no major changes to our extracorporeal membrane oxygenation circuit or changes to our transfusion threshold during the study period. The indication for extracorporeal membrane oxygenation, age, and severity of illness of the patients were similar before and after protocol initiation. Median blood product usage for packed RBCs, fresh frozen plasma, platelets, and cryoprecipitate decreased significantly after protocol initiation. The occurrence of cannula site bleeding decreased from 22% to 12% (p = 0.04), and surgical site bleeding decreased from 38% to 25% (p = 0.02). Median extracorporeal membrane oxygenation circuit life increased from 3.6 to 4.3 days (p = 0.02). A trend toward increased patient survival was noted, but it did not reach statistical significance.

CONCLUSIONS

We demonstrate an association between an extracorporeal membrane oxygenation anticoagulation laboratory protocol using anti-factor Xa assays, thromboelastography, and antithrombin measurements and a decrease in blood product transfusion, a decrease in hemorrhagic complications, and an increase in circuit life. To our knowledge, this is the first study to demonstrate clinical benefit associated with the use of these laboratory values for patients on extracorporeal membrane oxygenation.

Massive amounts of tissue factor induce fibrinogenolysis without tissue hypoperfusion in rats

Trauma-induced tissue factor (TF) release into the systemic circulation is considered to play an important role in the development of disseminated intravascular coagulation (DIC) immediately after severe trauma. However, the relationship between TF and hyperfibrinolysis, especially fibrinogenolysis, has been unclear. A total of 18 rats were divided into three groups: (a) the control group was infused with normal saline; (b) the low-dose group was infused with 4 U/kg TF; and (c) the high-dose group was infused with 16 U/kg TF. Arterial blood was drawn immediately and 2 and 4 h after the start of TF infusion. At each sampling point, arterial blood gases, platelet counts, and coagulation variables were measured. The fibrinogen degradation products were evaluated by a Western blot analysis. Hypotension, hypoxemia, and lactic acidosis were not observed in any of the three groups. In proportion to the doses of TF, the platelet counts, coagulation, and fibrinolysis variables deteriorated in line with DIC. The α2-plasmin inhibitor levels significantly decreased in the high-dose group compared with the other groups. The amounts of fibrinogen degradation products increased in proportion to the doses of TF. The plasmin-α2-plasmin inhibitor complex level in the high-dose group increased more than that of the other groups. In conclusion, TF can induce DIC associated with fibrinolysis and fibrinogenolysis without tissue hypoperfusion. The decrease in the α2-plasmin inhibitor level and the significant increase in the plasmin level may be the two main factors underlying the pathogenesis of hyperfibrin(ogen)olysis after TF administration.

Logistics of transfusion support for patients with massive hemorrhage

PURPOSE OF REVIEW

Traditionally, trauma resuscitation protocols have advocated sequential administration of therapeutic components, beginning with crystalloid solutions infused to replace lost intravascular volume. However, rapid restoration of the components of blood is essential for ensuring adequate tissue perfusion and for preventing acidosis, coagulopathy, and hypothermia, referred to as the 'lethal triad' in trauma settings. The review summarizes practical approaches for transfusion support of patients with massive hemorrhage.

RECENT FINDINGS

Massive transfusion protocols for blood transfusion support are reviewed, including practical considerations from our own. We maintain an inventory of thawed, previously frozen plasma (four units each of blood group O and A), which can be issued immediately for patients in whom the blood type is known. As frozen plasma requires 45 min to thaw, liquid AB plasma (26 day outdate) functions as an excellent alternative, particularly for patients with unknown or blood group B or AB types.

SUMMARY

Close monitoring of bleeding and coagulation in trauma patients allows goal-directed transfusions to optimize patients' coagulation, reduce exposure to blood products, and to improve patient outcomes. Future studies are needed to understand and demonstrate improved patient outcomes.

Association of hemodilution and blood pressure in uncontrolled bleeding

BACKGROUND

Hemodynamic status and coagulation capacity affect blood loss after injury. The most advantageous fluid and blood pressure to optimize resuscitation and minimize perturbation of coagulation are unclear. We investigated interactions of isovolumic hemodilution on hemodynamics, coagulation, and blood loss after injury.

METHODS

Twenty-five male rats were randomized into three groups (Whole Blood Uncontrolled Blood Pressure [WBU], n = 7; Lactated Ringers Uncontrolled Blood Pressure [LRU], n = 10; Whole Blood Controlled Blood Pressure [WBC], n = 8) with isovolumic hemodilution of 50% blood volume, with and without control of pre-injury blood pressure. All rats underwent uniform grade IV liver injury 30 min after serial exchanges. Post-injury blood loss and coagulation function were measured.

RESULTS

Dilution occurred, determined by hematocrit, with LRU having a greater reduction. Pre-injury mean arterial pressure (MAP) decreased compared with baseline (98 ± 7 mmHg) with LRU (62 ± 14 mmHg) and WBC (61 ± 10 mmHg), resulting in WBU (101 ± 13 mmHg) being significantly higher and not changed from baseline. Post-injury, MAP decreased from pre-injury, with LRU significantly lower than the other two groups. No differences were observed in prothrombin time/international normalized ratio or thromboelastography. Bleed volume was significantly different between groups: WBU < WBC < LRU and associated with the pre-injury MAP. Controlling baseline MAP, dilution with Lactated Ringers (LR) resulted in greater blood loss than whole blood (3.0 ± 0.4 versus 1.9 ± 0.3 mL).

CONCLUSIONS

In this rat model of liver injury, blood loss was associated with baseline MAP and type of fluid used for dilution. Hemodilution with LR did not produce coagulopathy based on laboratory values. When controlling baseline MAP, dilution with LR increased bleeding, confirming a functional coagulopathic state.

Massive transfusion in the trauma patient: Continuing Professional Development

PURPOSE

Massive transfusion has recently been given a dynamic definition, namely, the replacement of more than four red cell concentrates within an hour. The purpose of this continuing professional development module is to review the pathophysiology of hemorrhagic shock in the trauma patient and the current management strategies of the massively bleeding trauma patient.

PRINCIPAL FINDINGS

The massively bleeding trauma patient requires concurrent hemorrhage control and blood replacement therapy. Although there are many complications of massive transfusions, such as acid-base disturbances, electrolyte abnormalities, and hypothermia, perhaps the most difficult aspect to manage is acute trauma coagulopathy. Historically, coagulopathy was attributed to dilution of coagulation factors; however, recent accumulated evidence indicates that it is a multifactorial process associated with hypoperfusion, factor consumption, and hyperfibrinolysis. In an attempt to minimize acute trauma coagulopathy, massive transfusion protocols with equal ratios of red cell concentrates, frozen plasma, and platelets have been proposed. This type of hemostatic resuscitation, with near equal ratios of blood and blood products, has improved survival, but it is not without risk. In addition to the rapid and effective restoration of blood volume, the specific goal of transfusion management should be to maintain the patient's oxygen carrying capacity, hemostasis, and biochemistry.

CONCLUSION

The current literature does not permit firm conclusions to be drawn regarding optimal transfusion ratios. It remains appropriate, however, to devise a massive transfusion protocol at the institutional level that provides treating physicians with rapid delivery of a reasonable initial ratio of products. This would permit patient-centred management with an emphasis on surgical control of bleeding, maintenance of normothermia, avoidance of electrolyte abnormalities, acid-base balance, and the timely delivery of blood products.

OBJECTIVES

After reading this module, the reader should be able to: 1. Enumerate the complications associated with massive transfusion in the trauma context; 2. Understand how the coagulopathy present in the trauma patient differs from that seen in the elective setting; 3. Identify the modifications suggested by the recent literature for the management of massive transfusion in the trauma setting; 4. Appreciate the evidence for the institution of massive transfusion protocols.

Proteomic analyses of human plasma: Venus versus Mars

BACKGROUND

Plasma is vital for the resuscitation of injured patients and to restore necessary procoagulants, especially Factors (F)II, FV, FVII, FX, and FXIII; however, female plasma has been implicated in the majority of transfusion-related acute lung injury (TRALI) cases and male-only plasma transfusion regimens have significantly decreased the incidence of TRALI. Little is known about the human plasma proteome, and no comparisons have been made between male and female plasma; therefore, we hypothesize that there are significant differences between plasma from male and female donors.

STUDY DESIGN AND METHODS

Five units of fresh-frozen plasma each were collected from nulliparous female donors and male donors, and the proteome was analyzed by depleting the 14 most common proteins by immunoaffinity columns followed by protein separation by one dimension gel electrophoresis, tryptic digestion of the proteins, analysis of the peptides by liquid chromatography-tandem mass spectrometry, and identification employing human protein sequence databases.

RESULTS

Female plasma versus male plasma contained pregnancy zone protein (419- to 580-fold), FV (twofold), α(1)-antitrypsin (twofold), β(2) -microglobulin (twofold), and Complement Factors H and C4B (1.5- to 2-fold) at significantly higher concentrations than males and males contained significant increases in Fc-binding protein (twofold), protein Z-dependent protease inhibitor (twofold), phosphatidylinositol glycan-specific phospholipase (fourfold), protein S-100 (threefold), and transgelin-2 (14-fold) versus females (p < 0.005). The increases in FV, α(1)-antitrypsin, and β(2)-microglobulin were confirmed by an activity assay or immunoblots.

CONCLUSION

We conclude that there are proteomic differences between male and female plasma, which could be exploited to improve clinical outcomes in transfused patients.

Trauma, shock, and disseminated intravascular coagulation: lessons from the classical literature

A trauma patient's survival depends on the ability to control 2 opposing conditions, bleeding at the early phase and thrombosis at a late phase of trauma. The mixed existence of physiological responses for hemostasis and wound healing and pathological hemostatic responses makes it difficult to understand the mechanisms of the 2 stages of coagulopathy after trauma. Traumatic coagulopathy is multifactorial but disseminated intravascular coagulation (DIC) with the fibrinolytic phenotype is the predominant and initiative pathogenesis of coagulopathy at the early stage of trauma. High levels of inflammatory cytokines and severe tissue injuries activate the tissue-factor-dependent coagulation pathway followed by massive thrombin generation and its activation. Low levels of protein C and antithrombin induce insufficient coagulation control and the inhibition of the anticoagulation pathway. Primary and secondary fibrin(ogen)olysis is highly activated by the shock-induced tissue hypoxia and disseminated fibrin formation, respectively. Consumption coagulopathy and severe bleeding are subsequently observed in trauma patients. Persistently high levels of plasminogen activator inhibitor-1 expressed in the platelets and endothelium then change the DIC with the fibrinolytic phenotype into the thrombotic phenotype at approximately 24 to 48 hours after the onset of trauma. All of these changes coincide with the definition of DIC, which can be clearly distinguished from normal responses for hemostasis and wound healing by using sensitive molecular markers and DIC diagnostic criteria such as those outlined by the Japanese Association for Acute Medicine and the International Society on Thrombosis and Haemostasis. Treatments of DIC with the fibrinolytic phenotype involve the surgical repair of the trauma, improvement of shock, and the rapid and sufficient replacement of platelet concentrate, fresh frozen plasma, and depleted coagulation factors. The administration of an antifibrinolytic agent (tranexamic acid) may reduce the risk of death in bleeding trauma patients associated with this type of DIC.

Thrombelastography (TEG) or thromboelastometry (ROTEM) to monitor haemotherapy versus usual care in patients with massive transfusion

BACKGROUND

Severe bleeding and coagulopathy as a result of massive transfusion are serious clinical conditions that are associated with high mortality. Thromboelastography (TEG) and thromboelastometry (ROTEM) are increasingly used to guide transfusion strategy but their roles remain disputed.

OBJECTIVES

To systematically assess the benefits and harms of a TEG or ROTEM guided transfusion strategy in randomized trials involving patients with severe bleeding.

SEARCH STRATEGY

Randomized clinical trials (RCTs) were identified from electronic databases: Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2010, Issue 9); MEDLINE; EMBASE; Science Citation Index Expanded; International Web of Science; CINAHL; LILACS; and the Chinese Biomedical Literature Database (up to 31st October 2010). We contacted trial authors, authors of previous reviews, and manufacturers in the field.

SELECTION CRITERIA

We included all RCTs, irrespective of blinding or language, that compared transfusion guided by TEG or ROTEM to transfusion guided by clinical judgement and standard laboratory tests, or both.

DATA COLLECTION AND ANALYSIS

Two authors independently abstracted data; they resolved any disagreements by discussion. We presented pooled estimates of the intervention effects on dichotomous outcomes as relative risks (RR) and on continuous outcomes as mean differences, with 95% confidence intervals (CI). Our primary outcome measure was all cause mortality. We performed subgroup and sensitivity analyses to assess the effect of TEG or ROTEM in adults and children on various clinical and physiological outcomes. We assessed the risk of bias through assessment of trial methodological components and the risk of random error through trial sequential analysis.

MAIN RESULTS

We included nine RCTs with a total of 776 participants; only one trial had a low risk of bias. We found two ongoing trials but were unable to retrieve any data from them. Compared with standard treatment, TEG or ROTEM showed no statistically significant effect on overall mortality (3.78% versus 5.11%, RR 0.77, 95% CI 0.35 to 1.72; I(2) = 0%) but only five trials provided data on mortality. Our analyses demonstrated a statistically significant effect of TEG or ROTEM on the amount of bleeding (MD -85.05 ml, 95% CI -140.68 to -29.42; I(2) = 26%) but failed to show any statistically significant effect on other predefined outcomes.

AUTHORS' CONCLUSIONS

There is an absence of evidence that TEG or ROTEM improves morbidity or mortality in patients with severe bleeding. Application of a TEG or ROTEM guided transfusion strategy seems to reduce the amount of bleeding but whether this has implications for the clinical condition of patients is still uncertain. More research is needed.

Red blood cell transfusion in critically ill children: a narrative review

OBJECTIVE

To review the pathophysiology of anemia, as well as transfusion-related complications and indications for red blood cell (RBC) transfusion, in critically ill children. Although allogeneic blood has become increasingly safer from infectious agents, mounting evidence indicates that RBC transfusions are associated with complications and unfavorable outcomes. As a result, there has been growing interest and efforts to limit RBC transfusion, and indications are being revisited and revamped. Although a so-called restrictive RBC transfusion strategy has been shown to improve morbidity and mortality in critically ill adults, there have been relatively few studies on RBC transfusion performed in critically ill children.

DATA SOURCES

Published literature on transfusion medicine and outcomes of RBC transfusion. STUDY SELECTION, DATA EXTRACTION, AND SYNTHESIS: After a brief overview of physiology of oxygen transportation, anemia compensation, and current transfusion guidelines based on available literature, risks and outcomes of transfusion in general and in critically ill children are summarized in conjunction with studies investigating the safety of restrictive transfusion strategies in this patient population.

CONCLUSIONS

The available evidence does not support the extensive use of RBC transfusions in general or critically ill patients. Transfusions are still associated with risks, and although their benefits are established in limited situations, the associated negative outcomes in many more patients must be closely addressed. Given the frequency of anemia and its proven negative outcomes, transfusion decisions in the critically ill children should be based on individual patient's characteristics rather than generalized triggers, with consideration of potential risks and benefits, and available blood conservation strategies that can reduce transfusion needs.

Red blood cells accelerate the onset of clot formation in polytrauma and hemorrhagic shock

BACKGROUND

Hemorrhage and coagulopathy are major contributors to death after trauma. The contribution of red blood cells (RBCs) in correcting coagulopathy is poorly understood. Current methods of measuring coagulopathy may fail to accurately characterize in vivo clotting. We aimed to determine the effect of RBCs on clotting parameters by comparing resuscitation regimens containing RBCs and plasma with those containing plasma alone.

METHODS

Thirty-two Yorkshire swine were anesthetized, subjected to a complex model of polytrauma and hemorrhagic shock, and resuscitated with either fresh frozen plasma, lyophilized plasma (LP), or 1:1 ratios of fresh frozen plasma:packed RBC (PRBC) or LP:PRBC. Activated clotting time, prothrombin time, partial thromboplastin time, and thrombelastography (TEG) were performed at 1 hour, 2 hours, 3 hours, and 4 hours after resuscitation.

RESULTS

Animals treated with 1:1 LP:PRBC had less blood loss than the other groups (p < 0.05). The activated clotting time was shorter in the 1:1 groups when compared with the pure plasma groups at all time points (p < 0.05). The 1:1 groups had shorter TEG R times (time to onset of clotting) at 1 hour, 3 hours, and 4 hours compared with pure plasma groups (p < 0.05). Other TEG parameters did not differ between groups. Partial thromboplastin time was shorter in the pure plasma groups than the 1:1 groups at all time points (p < 0.05).

CONCLUSIONS

Whole blood assays reveal that RBCs accelerate the onset of clot formation. Coagulation assays using spun plasma underestimate the effect of RBCs on clotting and do not completely characterize clot formation.

Reappraising the concept of massive transfusion in trauma

INTRODUCTION

The massive-transfusion concept was introduced to recognize the dilutional complications resulting from large volumes of packed red blood cells (PRBCs). Definitions of massive transfusion vary and lack supporting clinical evidence. Damage-control resuscitation regimens of modern trauma care are targeted to the early correction of acute traumatic coagulopathy. The aim of this study was to identify a clinically relevant definition of trauma massive transfusion based on clinical outcomes. We also examined whether the concept was useful in that early prediction of massive transfusion requirements could allow early activation of blood bank protocols.

METHODS

Datasets on trauma admissions over a 1 or 2-year period were obtained from the trauma registries of five large trauma research networks. A fractional polynomial was used to model the transfusion-associated probability of death. A logistic regression model for the prediction of massive transfusion, defined as 10 or more units of red cell transfusions, was developed.

RESULTS

In total, 5,693 patient records were available for analysis. Mortality increased as transfusion requirements increased, but the model indicated no threshold effect. Mortality was 9% in patients who received none to five PRBC units, 22% in patients receiving six to nine PRBC units, and 42% in patients receiving 10 or more units. A logistic model for prediction of massive transfusion was developed and validated at multiple sites but achieved only moderate performance. The area under the receiver operating characteristic curve was 0.81, with specificity of only 50% at a sensitivity of 90% for the prediction of 10 or more PRBC units. Performance varied widely at different trauma centers, with specificity varying from 48% to 91%.

CONCLUSIONS

No threshold for definition exists at which a massive transfusion specifically results in worse outcomes. Even with a large sample size across multiple trauma datasets, it was not possible to develop a transportable and clinically useful prediction model based on available admission parameters. Massive transfusion as a concept in trauma has limited utility, and emphasis should be placed on identifying patients with massive hemorrhage and acute traumatic coagulopathy.

Blood product ratio in acute traumatic coagulopathy--effect on mortality in a Scandinavian level 1 trauma centre

Background

Trauma is the leading cause of loss of life expectancy worldwide. In the most seriously injured patients, coagulopathy is often present on admission. Therefore, transfusion strategies to increase the ratio of plasma (FFP) and platelets (PLT) to red blood cells (RBC), simulating whole blood, have been introduced. Several studies report that higher ratios improve survival in massively bleeding patients. Here, the aim was to investigate the potential effect of increased FFP and PLT to RBC on mortality in trauma patients.

Methods

In a retrospective before and after study, all trauma patients primarily admitted to a level-one Trauma Centre, receiving blood transfusion, in 2001-3 (n = 97) and 2005-7 (n = 156), were included. In 2001-3, FFP and PLT were administered in accordance with the American Society of Anesthesiologists (ASA) guidelines whereas in 2005-7, Hemostatic Control Resuscitation (HCR) entailing pre-emptive use of FFP and PLT in transfusion packages during uncontrolled haemorrhage and thereafter guided by thrombelastograph (TEG) analysis was employed. The effect of transfusion therapy and coagulopathy on mortality was investigated.

Results

Patients included in the early and late period had comparable demography, injury severity score (ISS), admission hematology and coagulopathy (27% vs. 34% had APTT above normal). There was a significant change in blood transfusion practice with shorter time interval from admission to first transfusion (median time 3 min vs.28 min in massive bleeders, p < 0.001), transfusion of higher ratios of FFP:RBC, PLT:RBC and PLT:FFP in the HCR group but 30-day mortality remained comparable in the two periods. In the 2005-7 period, higher age, ISS and Activated Partial Thromboplastin Time (APTT) above normal were independent predictors of mortality whereas no association was fund between blood product ratios and mortality.

Conclusion

Aggressive administration of FFP and PLT did not influence mortality in the present trauma population.

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

BACKGROUND

Continued hemorrhage remains a major cause of mortality in massively transfused patients, many of whom develop coagulopathy. A review of transfusion practice for these patients at our hospital revealed that a significant proportion received suboptimal transfusion therapy. Survivors had higher platelets count than non-survivors.

METHODS

For massively transfused patients with hemodynamic instability, we introduced the concept of transfusion packages comprising five units of red blood cells, five units of fresh frozen plasma and two units of platelet concentrates. Thrombelastogram analysis was validated for routine laboratory use and implemented in the blood bank for monitoring coagulopathy and guiding transfusion therapy. Anaesthetists at our hospital were trained in functional haemostasis management based on analysis of thrombelastograms.

RESULTS

Intraoperative administration of transfusion packages for patients operated on for a ruptured abdominal aortic aneurysm was associated with a reduction in mortality from 56% to 34% (p = 0.02). When comparing massively transfused patients treated with hemostatic control resuscitation, i.e., transfusion package therapy during hemodynamic instability and thromboelastogram--monitored and guided transfusion therapy, with controls treated in accordance with existing transfusion guidelines, mortality was reduced from 31% to 20% (p = 0.002).

CONCLUSION

The initiative from the blood bank, i.e., transfusion packages for patients with uncontrollable bleeding and based on the thromboelastogram when hemodynamic control is established, has improved the transfusion practice and survival in massively transfused patients at our hospital.

Massive transfusion and blood product use in the pediatric trauma patient

Hemorrhagic shock in the pediatric trauma patient is an uncommon but fundamental problem for the treating clinician. Current management of hemorrhagic shock involves initial resuscitation with crystalloid fluids followed by infusion of blood components as necessary. In management of the adult trauma patient, many institutions have implemented massive transfusion protocols to guide transfusion in situations requiring or anticipating the use of greater than 10 U of packed red blood cells. In the pediatric population, guidelines for massive transfusion are vague or nonexistent. Adult trauma transfusion protocols can be applied to children until a pediatric protocol is validated. Here, we attempt to identify certain principles of transfusion therapy specific to pediatric trauma and outline a sample pediatric massive transfusion protocol that may be used to guide resuscitation. Also, adjuncts to transfusion, such as colloid fluids, other plasma expanders or hemoglobin substitutes, and recombinant activated factor VII, are discussed.

Outcomes following early red blood cell transfusion in acute upper gastrointestinal bleeding

BACKGROUND

Acute upper gastrointestinal bleeding (AUGIB) accounts for 14% of RBC units transfused in the UK. In exsanguinating AUGIB the value of RBC transfusion is self evident, but in less severe bleeding its value is less obvious.

AIM

To examine the relationship between early RBC transfusion, re-bleeding and mortality following AUGIB, which is one of the most common indications for red blood cell (RBC) transfusion.

METHOD

Data were collected on 4441 AUGIB patients presenting to UK hospitals. The relationship between early RBC transfusion, re-bleeding and death was examined using logistic regression.

RESULTS

44% were transfused RBCs within 12 hours of admission. In patients transfused with an initial haemoglobin of <8 g/dl, re-bleeding occurred in 23% and mortality was 13% compared with a re-bleeding rate of 15%, and mortality of 13% in those not transfused. In patients transfused with haemoglobin >8 g/dl, re-bleeding occurred in 24% and mortality was 11% compared with a re-bleeding rate of 6.7%, and mortality of 4.3% in those not transfused. After adjusting for Rockall score and initial haemoglobin, early transfusion was associated with a two-fold increased risk of re-bleeding (Odds ratio 2.26, 95% CI 1.76-2.90) and a 28% increase in mortality (Odds ratio 1.28, 95% CI 0.94-1.74).

CONCLUSIONS

Early RBC transfusion in AUGIB was associated with a two-fold increased risk of re-bleeding and an increase in mortality, although the latter was not statistically significant. Although these findings could be due to residual confounding, they indicate that a randomized comparison of restrictive and liberal transfusion policies in AUGIB is urgently required.

Postoperative spinal epidural hematoma at a site distant from the main surgical procedure: a case report and review of the literature

BACKGROUND CONTEXT

Postoperative spinal epidural hematomas are known complications of spinal surgery. However, to our knowledge, there are no known cases of postoperative spinal epidural hematoma that occurred distant from the portion of the procedure that breached the spinal canal.

PURPOSE

To report a case and review the literature on the development of postoperative spinal epidural hematoma at a site distant from the portion of the surgical procedure that breached the spinal canal.

STUDY DESIGN

Case report and review of the literature.

METHODS

One patient at our institution developed a hematoma at a site distant from the surgical procedure that breached the spinal canal. We retrospectively reviewed the patient's clinical charts, radiographs, and computed tomography scans.

RESULTS

A 57-year-old woman with adult scoliosis and junctional kyphosis underwent a pedicle subtraction osteotomy and long spinal fusion from T3 to the sacrum. Three hours postoperatively, she developed paraplegia with a neurologic deficit at a level distant from the site at which the spinal canal was surgically breached. A computed tomography myelogram revealed a spinal epidural hematoma that was causing compression of the spinal cord in the upper thoracic spine. The patient was returned to the operating room emergently and underwent laminectomy and hematoma evacuation. She had near-complete recovery 5 months after surgery.

CONCLUSION

Spinal epidural hematomas are rare but dangerous complications that can result in severe neurologic deficits. A neurologic examination should always be conducted in the operating room immediately after surgery; if it is abnormal, spinal epidural hematoma should be suspected. If the examination indicates a deficit at a site distant from the original surgery, then diagnostic reimaging (magnetic resonance imaging or computed tomography myelogram) is indicated.

Correction of coagulation in dilutional coagulopathy: use of kinetic and capacitive coagulation assays to improve hemostasis

The management of dilutional coagulopathy due to fluid infusion and massive blood loss is a topic that deserves a biochemical approach. In this review article, we provide an overview of current guidelines and recommendations on diagnosis and on management of transfusion in acquired coagulopathy. We discuss the biochemical differences between kinetic clotting assays (clotting times) and new capacitive coagulation measurements that provide time-dependent information on thrombin generation and fibrin clot formation. The available evidence suggests that a combination of assay types is required for evaluating new transfusion protocols aimed to optimize hemostasis and stop bleeding. Although there is current consensus on the application of fresh frozen plasma to revert coagulopathy, factor concentrates may appear to be useful in the future.

Massive transfusion: new insights

Massive transfusion (MT) is used for the treatment of uncontrolled hemorrhage. Earlier definitive control of life-threatening hemorrhage has significantly improved patient outcomes, but MT is still required. A number of recent advances in the area of MT have emerged, including the use of "hypotensive" or "delayed" resuscitation for victims of penetrating trauma before hemorrhage is controlled and "hemostatic resuscitation" with increased use of plasma and platelet transfusions in an attempt to maintain coagulation. These advances include the earlier use of hemostatic blood products (plasma, platelets, and cryoprecipitate), recombinant factor VIIa as an adjunct to the treatment of dilutional and consumptive coagulopathy, and a reduction in the use of isotonic crystalloid resuscitation. MT protocols have been developed to simplify and standardize transfusion practices. The authors of recent studies have advocated a 1:1:1 ratio of packed RBCs to fresh frozen plasma to platelet transfusions in patients requiring MT to avoid dilutional and consumptive coagulopathy and thrombocytopenia, and this has been associated with decreased mortality in recent reports from combat and civilian trauma. Earlier assessment of the exact nature of abnormalities in hemostasis has also been advocated to direct specific component and pharmacologic therapy to restore hemostasis, particularly in the determination of ongoing fibrinolysis.

Validation of a theoretically derived model for the management of massive blood loss in pediatric patients - a case report

We present the case of a 5-year-old girl who was brought to hospital having suffered an intracranial bleed. She was found to have a large cerebral arteriovenous malformation which was unsuitable for coiling. Uncontrollable raised intracranial pressure refractory to all therapies necessitated surgery as a last resort. Massive hemorrhage eventuated during the procedure with the estimated loss of between five and six blood volumes, the majority occurring within the space of an hour and a half. We describe management using a locally developed protocol and correlate this with laboratory findings.

Effect of Haemostatic Control Resuscitation on mortality in massively bleeding patients: a before and after study

BACKGROUND AND OBJECTIVES

Evidence supporting the use of platelets and plasma in resuscitation of massive bleedings is questionable. Current consensus guidelines recommend restrictive use. Our aim was to determine the effect of changing the transfusion practice on 30-day survival in massively bleeding patients.

MATERIALS AND METHODS

Consecutive adult patients receiving more than 10 units of red blood cells (RBC) within 24 h 2 years prior to (2002-2003) and 2 years after (2005-2006) a change in transfusion practice were included. In 2004, we implemented Haemostatic Control Resuscitation (HCR) with preemptive use of platelets and plasma, administered in transfusion packages, comprising 5 units of RBCs, 5 units of fresh-frozen plasma and 2 units of platelet concentrates (PC), when massive bleeding occurred or upon arrival at the emergency room and thereafter directed by thrombelastography throughout the peri- and postoperative period.

RESULTS

In 2005-2006, the 442 patients received more PCs within 24 h from admission [mean 5.0 (SD 4.2) vs. 1.7 (2.0); P < 0.0001] and had a smaller decrease in platelet count during the bleeding episode [91.5 (81.2) vs. 119.7 (100.8) x 10(9)/l; P = 0.0025] than the 390 patients treated in 2002-2003. Thirty-day mortality was reduced in 2005-2006 (20.4% vs. 31.5%; P = 0.0002) and at 90-day (22.4% vs. 34.6%; P < 0.0001) as compared to 2002-2003.

CONCLUSIONS

In patients who experience massive bleeding, HCR with platelets and plasma, as guided by thrombelastography, is associated with improved survival. While confirmation from a randomized controlled trial is urgently needed, HCR may be considered in these patients.

Early aggressive use of fresh frozen plasma does not improve outcome in critically injured trauma patients

OBJECTIVES

Recent data from Iraq supporting early aggressive use of fresh frozen plasma (FFP) in a 1:1 ratio to packed red blood cells (PRBCs) has led many civilian trauma centers to adopt this resource intensive strategy.

METHODS

Prospective data were collected on 806 consecutive trauma patients admitted to the intensive care unit over 2 years. Patients were stratified by PRBC:FFP transfusion ratio over the first 24 hours. Stepwise regression models were performed controlling for age, gender, mechanism of injury, injury severity, and acute physiology and chronic health evaluation (APACHE) 2 score to determine if early aggressive use of PRBC:FFP improved outcome.

RESULTS

Seventy-seven percent of patients were male (N = 617) and 85% sustained blunt injury (n = 680). Mean age, injury severity score (ISS), and APACHE score were 43 +/- 20 years, 29 +/- 13, and 13 +/- 7, respectively. Mean number of PRBCs and FFP transfused were 7.7 +/- 12 U, 6 U, and 5 +/- 12 U, respectively. Three hundred sixty-five (45%) patients were transfused in the first 24 hours. Sixty-eight percent (n = 250) of them received both PRBCs and FFP. Analyzing these patients by stepwise regression controlling for all significant variables, the PRBC:FFP ratio did not predict intensive care unit days, hospital days, or mortality even in patients who received massive transfusion (> or = 10 U). Furthermore, there was no significant difference in outcome when comparing patients who had a 1:1 PRBC:FFP ratio with those who did not receive any FFP.

CONCLUSION

Early and aggressive use of FFP does not improve outcome after civilian injury. This may reflect inherent differences compared with military injury; however, this practice should be reevaluated.

Effects of plasma dilution on tissue-factor-induced thrombin generation and thromboelastography: partly compensating role of platelets

BACKGROUND

Bleeding upon major surgery or severe trauma is treated by transfusion with crystalloids, colloids, or plasma. This treatment, however, can lead to dilutional coagulopathy and impaired hemostasis. We investigated the suitability of two integrative coagulation tests to measure the hemostatic activity of diluted plasma.

STUDY DESIGN AND METHODS

Plasma from healthy donors was diluted in vitro with saline or colloid (venofundin or gelofusin). Coagulant activity in response to tissue factor was monitored by calibrated automated thrombin (CAT) generation and rotational thromboelastography (TEG), detecting formation of elastic fibrin clots. Plasma from patients receiving fluid infusion during coronary artery bypass grafting (CABG) was analyzed with the same assays.

RESULTS

Optimal activity of CAT and TEG assays required the presence of 10 pmol per L tissue factor and 4 micromol per L phospholipid vesicles or 100 x 10(9) platelets (PLTs) per L. Strikingly, thrombin generation and clot formation became impaired at a higher extent of dilution with PLTs present (< or =40% plasma) than with phospholipid vesicles present (< or =60% plasma). Colloids aggravated the dilution effect on clot formation, but FFP antagonized the dilution effect on thrombin and clot formation. In contrast, fibrinogen and Factor (F)XIII only restored the impaired clot formation. In plasma samples from patients undergoing CABG, CAT and TEG assay variables were altered to an extent corresponding with the volume of fluid infusion.

CONCLUSION

Thrombin generation and clot formation are reduced at a plasma dilution of more than 40 percent. In either process, PLTs can partly compensate for the dilution effect. In vitro dilution with colloids impaired fibrin clot elasticity compared to saline.