Predicting massive blood transfusion using clinical scores post-trauma

Evaluating the Shock Index, Revised Assessment of Bleeding and Transfusion (RABT), Assessment of Blood Consumption (ABC) and novel PTTrauma score to predict critical transfusion threshold (CAT) in penetrating thoracic trauma

The shock index (SI) has been associated with predicting transfusion needs in trauma patients. However, its utility in penetrating thoracic trauma (PTTrauma) for predicting the Critical Administration Threshold (CAT) has not been well-studied. This study aimed to evaluate the prognostic value of SI in predicting CAT in PTTrauma patients and compare its performance with the Assessment of Blood Consumption (ABC) and Revised Assessment of Bleeding and Transfusion (RABT) scores. We conducted a prognostic type 2, single-center retrospective observational cohort study on patients with PTTrauma and an Injury Severity Score (ISS) > 9. The primary exposure was SI at admission, and the primary outcome was CAT. Logistic regression and decision curve analysis were used to assess the predictive performance of SI and the PTTrauma score, a novel model incorporating clinical variables. Of the 620 participants, 53 (8.5%) had more than one CAT. An SI > 0.9 was associated with CAT (adjusted OR 4.89, 95% CI 1.64-14.60). The PTTrauma score outperformed SI, ABC, and RABT scores in predicting CAT (AUC 0.867, 95% CI 0.826-0.908). SI is a valuable predictor of CAT in PTTrauma patients. The novel PTTrauma score demonstrates superior performance compared to existing scores, highlighting the importance of developing targeted predictive models for specific injury patterns. These findings can guide clinical decision-making and resource allocation in the management of PTTrauma.

Blood lactate after pre-hospital blood transfusion for major trauma by helicopter emergency medical services

BACKGROUND AND OBJECTIVES

The appropriate use of blood components is essential for ethical use of a precious, donated product. The aim of this study was to report in-hospital red blood cell (RBC) transfusion after pre-hospital transfusion by helicopter emergency medical service paramedics. A secondary aim was to assess the potential for venous blood lactate to predict ongoing transfusion.

MATERIALS AND METHODS

All patients who received RBC in air ambulance were transported to a single adult major trauma centre, had venous blood lactate measured on arrival and did not die before ability to transfuse RBC were included. The association of venous blood lactate with ongoing RBC transfusion was assessed using multi-variable logistic regression analysis and reported using adjusted odds ratios (aOR). The discriminative ability of venous blood lactate was assessed using area under receiver operating characteristics curve (AUROC).

RESULTS

From 1 January 2016 to 15 May 2019, there were 165 eligible patients, and 128 patients were included. In-hospital transfusion occurred in 97 (75.8%) of patients. Blood lactate was associated with ongoing RBC transfusion (aOR: 2.00; 95% confidence interval [CI]: 1.36-2.94). Blood lactate provided acceptable discriminative ability for ongoing transfusion (AUROC: 0.78; 95% CI: 0.70-0.86).

CONCLUSIONS

After excluding patients with early deaths, a quarter of those who had prehospital RBC transfusion had no further transfusion in hospital. Venous blood lactate appears to provide value in identifying such patients. Lactate levels after pre-hospital transfusion could be used as a biomarker for transfusion requirement after trauma.

Could machine learning algorithms help us predict massive bleeding at prehospital level?

OBJECTIVE

Comparison of the predictive ability of various machine learning algorithms (MLA) versus traditional prediction scales (TPS) for massive hemorrhage (MH) in patients with severe traumatic injury (STI).

DESIGN

On a database of a retrospective cohort with prehospital clinical variables and MH outcome, a treatment of the database was performed to be able to apply the different AML, obtaining a total set of 473 patients (80% training, 20% validation). For modeling, proportional imputation and cross validation were performed. The predictive power was evaluated with the ROC metric and the importance of the variables using the Shapley values.

SETTING

Out-of-hospital care of patients with STI.

PARTICIPANTS

Patients with STI treated out-of-hospital by a out-of-hospital medical service from January 2010 to December 2015 and transferred to a trauma center in Madrid.

INTERVENTIONS

None.

MAIN VARIABLES OF INTEREST

Obtaining and comparing the "Receiver Operating Characteristic curve" (ROC curve) metric of four MLAs: "random forest" (RF), "vector support machine" (SVM), "gradient boosting machine" (GBM) and "neural network" (NN) with the results obtained with TPS.

RESULTS

The different AML reached ROC values higher than 0.85, having medians close to 0.98. We found no significant differences between AMLs. Each AML offers a different set of more important variables with a predominance of hemodynamic, resuscitation variables and neurological impairment.

CONCLUSIONS

MLA may be helpful in patients with HM by outperforming TPS.

A prediction model for massive hemorrhage in trauma: a retrospective observational study

Background

Massive hemorrhage is the main cause of preventable death after trauma. This study aimed to establish prediction models for early diagnosis of massive hemorrhage in trauma.

Methods

Using the trauma database of Chinese PLA General Hospital, two logistic regression (LR) models were fit to predict the risk of massive hemorrhage in trauma. Sixty-two potential predictive variables, including clinical symptoms, vital signs, laboratory tests, and imaging results, were included in this study. Variable selection was done using the least absolute shrinkage and selection operator (LASSO) method. The first model was constructed based on LASSO feature selection results. The second model was constructed based on the first vital sign recordings of trauma patients after admission. Finally, a web calculator was developed for clinical use.

Results

A total of 2353 patients were included in this study. There were 377 (16.02%) patients with massive hemorrhage. The selected predictive variables were heart rate (OR: 1.01; 95% CI: 1.01–1.02; P<0.001), pulse pressure (OR: 0.99; 95% CI: 0.98–0.99; P = 0.004), base excess (OR: 0.90; 95% CI: 0.87–0.93; P<0.001), hemoglobin (OR: 0.95; 95% CI: 0.95–0.96; P<0.001), displaced pelvic fracture (OR: 2.13; 95% CI: 1.48–3.06; P<0.001), and a positive computed tomography scan or positive focused assessment with sonography for trauma (OR: 1.62; 95% CI: 1.21–2.18; P = 0.001). Model 1, which was developed based on LASSO feature selection results and LR, displayed excellent discrimination (AUC: 0.894; 95% CI: 0.875–0.912), good calibration (P = 0.405), and clinical utility. In addition, the predictive power of model 1 was better than that of model 2 (AUC: 0.718; 95% CI: 0.679–0.757). Model 1 was deployed as a public web tool (http://82.156.217.249:8080/).

Conclusions

Our study developed and validated prediction models to assist medical staff in the early diagnosis of massive hemorrhage in trauma. An open web calculator was developed to facilitate the practical application of the research results.

Predictors of transfusion in trauma and their utility in the prehospital environment: a scoping review

Background: Hemorrhage is a leading cause of preventable mortality from trauma, necessitating resuscitation through blood product transfusions. Early and accurate identification of patients requiring transfusions in the prehospital setting may reduce delays in time to transfusion upon arrival to hospital, reducing mortality. The purpose of this study is to characterize existing literature on predictors of transfusion and analyze their utility in the prehospital context.Objectives: The objectives of this study are to characterize the existing quantity and quality of literature regarding predictor scores for transfusion in injured patients, and to analyse the utility of predictor scores for massive transfusions in the prehospital setting and identify prehospital predictor scores for future research.Methods: A search strategy was developed in consultation with information specialists. A literature search of OVID MEDLINE from 1946 to present was conducted for primary studies evaluating the predictive ability of scoring systems or single variables in predicting transfusion in all trauma settings.Results: Of the 5824 studies were identified, 5784 studies underwent title and abstract screening, 94 studies underwent full text review, and 72 studies were included in the final review. We identified 16 single variables and 52 scoring systems for predicting transfusion. Amongst single predictor variables, fluids administered and systolic blood pressure had the highest reported sensitivity (100%) and specificity (89%) for massive transfusion protocol (MTP) activation respectively. Amongst scoring systems for transfusion, the Shock Index and Modified Shock Index had the highest reported sensitivity (96%), while the Pre-arrival Model had the highest reported specificity (95%) for MTP activation. Overall, 20 scores were identified as being applicable to the prehospital setting, 25 scores were identified as being potentially applicable, and seven scores were identified as being not applicable.Conclusions: We identified an extensive list of predictive single variables, validated scoring systems, and derived models for massive transfusion, presented their properties, and identified those with potential utility in the prehospital setting. By further validating applicable scoring tools in the prehospital setting, we may begin to administer more timely transfusions in the trauma population.

Major Prehospital Trauma and In-Hospital Emergencies: Massive Transfusion Triggers

BACKGROUND

Massive transfusion (MT) in trauma is initiated on the basis of factors of different natures and depending on protocols and scales used both in prehospital and in-hospital care areas.

OBJECTIVE

The main goal was to analyze and relate factors and predictive variables for MT requirements considering both health care areas.

METHOD

This was a retrospective cohort study that included patients who were treated either at the emergency department of a large hospital or through prehospital care before arrival at the hospital. The patients included were adults who received MT, defined as a blood bank request of 10 or more units of red cells in the first 24 hours or 5 or more within 4 hours of trauma, from January 1, 2009, to January 1, 2017. The variables included were individual characteristics and those associated with the trauma, clinical-analytical assessment, resuscitation, timing, and survival.

RESULTS

A total of 52 patients who received MT were included. The average age of the patients was 41.23 ± 16.06 years, a mean of 19.56 ± 12.77 units was administered, and the mortality rate was 21.2%.

DISCUSSION

Injury mechanism, clinical-analytical variables, and resuscitation strategies have a significant influence on the need for MT; therefore, early identification is fundamental for performing quality management and addressing avoidable factors during MT processes.

Review of Existing Scoring Systems for Massive Blood Transfusion in Trauma Patients: Where Do We Stand?

BACKGROUND

Uncontrolled bleeding is the main cause of the potential preventable death in trauma patients. Accordingly, we reviewed all the existing scores for massive transfusion posttraumatic hemorrhage and summarized their characteristics, thus making it easier for the reader to have a global view of these scores-how they were created, their accuracy and to which population they apply.

METHODS

A narrative review with a systematic search method to retrieve the journal articles on the predictive scores or models for massive transfusion was carried out. A literature search using PubMed, SCOPUS, and Google scholar was performed using relevant keywords in different combinations. The keywords used were "massive transfusion," "score," "model," "trauma," and "hemorrhage" in different combinations. The search was limited for full-text articles published in English language, human species and for the duration from January 1, 1998 to November 30, 2018.

RESULTS

The database search yielded 295 articles. The search was then restricted to the inclusion criteria which retrieved 241 articles. Duplicates were removed and full-texts were assessed for the eligibility to include in the review which resulted in inclusion of 24 articles. These articles identified 24 scoring systems including modified or revised scores. Different models and scores for identifying patients requiring massive transfusion in military and civilian settings have been described. Many of these scorings were complex with difficult calculation, while some were simple and easy to remember.

CONCLUSIONS

The current prevailing practice that is best described as institutional or provider centered should be supplemented with score-based protocol with auditing and monitoring tools to refine it. This review summarizes the current scoring models in predicting the need for MT in civilian and military trauma. Several questions remain open; i.e., do we need to develop new score, merge scores, modify scores, or adopt existing score for certain trauma setting?

Systematic reviews of scores and predictors to trigger activation of massive transfusion protocols

BACKGROUND

The use of massive transfusion protocols (MTPs) in the resuscitation of hemorrhaging trauma patients ensures rapid delivery of blood products to improve outcomes, where the decision to trigger MTPs early is important. Scores and tools to predict the need for MTP activation have been developed for use to aid with clinical judgment. We performed a systematic review to assess (1) the scores and tools available to predict MTP in trauma patients, (2) their clinical value and diagnostic accuracies, and (3) additional predictors of MTP.

METHODS

MEDLINE, EMBASE, and CENTRAL were searched from inception to June 2017. All studies that utilized scores or predictors of MTP activation in adult (age, ≥18 years) trauma patients were included. Data collection for scores and tools included reported sensitivities and specificities and accuracy as defined by the area under the curve of the receiver operating characteristic.

RESULTS

Forty-five articles were eligible for analysis, with 11 validated and four unvalidated scores and tools assessed. Of four scores using clinical assessment, laboratory values, and ultrasound assessment the modified Traumatic Bleeding Severity Score had the best performance. Of those scores, the Trauma Associated Severe Hemorrhage score is most well validated and has higher area under the curve of the receiver operating characteristic than the Assessment of Blood Consumption and Prince of Wales scores. Without laboratory results, the Assessment of Blood Consumption score balances accuracy with ease of use. Without ultrasound use, the Vandromme and Schreiber scores have the highest accuracy and sensitivity respectively. The Shock Index uses clinical assessment only with fair performance. Other clinical variables, laboratory values, and use of point-of-care testing results were identified predictors of MTP activation.

CONCLUSION

The use of scores or tools to predict MTP need to be individualized to hospital resources and skill set to aid clinical judgment. Future studies for triggering nontrauma MTP activations are needed.

LEVEL OF EVIDENCE

Systematic review, level III.

Early prediction of acute traumatic coagulopathy: a validation of the COAST score using the German Trauma Registry

BACKGROUND

Early identification of trauma patients at risk of developing acute traumatic coagulopathy (ATC) is important for initiating appropriate, coagulopathy-focused treatment. A clinical ATC prediction tool is a quick, simple method to evaluate risk. The COAST score was developed and validated in Australia but is yet to be validated on a European population. We validated the ability of the COAST score to predict coagulopathy and adverse bleeding-related outcomes on a large European trauma population.

METHODS

The COAST score was modified and applied to a retrospective cohort of trauma patients from the German Trauma Registry (TR-DGU). The primary outcome was coagulopathy defined as INR > 1.5 or aPTT > 60 s. Secondary outcomes were massive transfusion, blood product requirements, urgent surgery and mortality. The cohort included adult trauma patients with Injury Severity Score > 15 treated in Germany/Austria in 2012-2016.

RESULTS

15,370 cases were included, of which 10.9% were coagulopathic. The COAST score performed with sensitivity 21.6% and specificity 94.2% at a threshold of COAST ≥ 3. The AUROC was 0.625 (95% CI 0.61-0.64). The COAST score also identified patients who had more massive transfusions (15.3% v 1.6%), more emergency surgery (49.6% v 28.2%), and higher early (21.7% v 5.4%) and total in-hospital mortality (38.1% v 14.5%).

CONCLUSION

This large retrospective study demonstrated that the modified COAST score predicts coagulopathy with low sensitivity but high specificity. A positive COAST score identified a group of patients with bleeding-related adverse outcomes. This score appears adequate to act as an inclusion criterion for clinical trials targeting ATC.

Shock index increase from the field to the emergency room is associated with higher odds of massive transfusion in trauma patients with stable blood pressure: A cross-sectional analysis

Background

The shock index (SI) is defined as the ratio of heart rate/systolic blood pressure. This study aimed to determine the performance of delta shock index (ΔSI), a difference between SI upon arrival at the emergency room (ER) and that in the field, in predicting the need for massive transfusion (MT) among adult trauma patients with stable blood pressure.

Methods

This study included registered data from all trauma patients aged 20 years and above who were hospitalized from January 1, 2009 to December 31, 2016. Only patients who were transferred by emergency medical service from the accident site with a systolic blood pressure ≥ 90 mm Hg at the ER were included. The 7,957 enrolled trauma patients were divided into 2 groups, those who had received blood transfusion ≥ 10 U (MT, n = 82) and those who had not (non-MT, n = 7,875). The odds ratios with 95% confidence intervals for the need for MT by a given ΔSI were measured. The plot of specific receiver operating characteristic (ROC) curves was used to evaluate the best cutoff point of ΔSI that could predict the patient’s probability of receiving MT.

Results

ROC curve analysis showed that a ΔSI of 0.06 as the cutoff point had the highest AUC of 0.61, with a sensitivity of 0.415 and specificity of 0.841. Patients with a ΔSI ≥ 0.00 had a significant 1.8-fold increase in need for MT than those patients with a ΔSI less than 0.00 (1.4% vs. 0.8%, p = 0.01). The larger the ΔSI, the higher the odds of need for an MT. Using the cutoff point of ΔSI of 0.06, patients with a ΔSI ≥ 0.06 had a significant 3.7-fold increase in need for MT than those patients with a ΔSI less than 0.06 (2.7% vs. 0.7%, p < 0.001).

Conclusions

This study indicated that, in trauma patients with stable blood pressure at the ER, the accuracy of prediction of the requirement for MT by ΔSI is low. However, the size of the delta is significantly associated with need for MT and a lack of improvement in the patient’s SI at the ER compared to that in the field significantly increases the odds of a need for MT.

External validation of a smartphone app model to predict the need for massive transfusion using five different definitions

BACKGROUND

Previously, a model to predict massive transfusion protocol (MTP) (activation) was derived using a single-institution data set. The PRospective, Observational, Multicenter, Major Trauma Transfusion database was used to externally validate this model's ability to predict both MTP activation and massive transfusion (MT) administration using multiple MT definitions.

METHODS

The app model was used to calculate the predicted probability of MTP activation or MT delivery. The five definitions of MT used were: (1) 10 units packed red blood cells (PRBCs) in 24 hours, (2) Resuscitation Intensity score ≥ 4, (3) critical administration threshold, (4) 4 units PRBCs in 4 hours; and (5) 6 units PRBCs in 6 hours. Receiver operating curves were plotted to compare the predicted probability of MT with observed outcomes.

RESULTS

Of 1,245 patients in the data set, 297 (24%) met definition 1, 570 (47%) met definition 2, 364 (33%) met definition 3, 599 met definition 4 (49.1%), and 395 met definition 5 (32.4%). Regardless of the outcome (MTP activation or MT administration), the predictive ability of the app model was consistent: when predicting activation of the MTP, the area under the curve for the model was 0.694 and when predicting MT administration, the area under the curve ranged from 0.695 to 0.711.

CONCLUSION

Regardless of the definition of MT used, the app model demonstrates moderate ability to predict the need for MT in an external, homogenous population. Importantly, the app allows the model to be iteratively recalibrated ("machine learning") and thus could improve its predictive capability as additional data are accrued.

LEVEL OF EVIDENCE

Diagnostic test study/Prognostic study, level III.

The Value of Red Cell Distribution Width (RDW) and Trauma-Associated Severe Hemorrhage (TASH) in Predicting Hospital Mortality in Multiple Trauma Patients

OBJECTIVE

To investigate the role of red cell distribution width (RDW) in comparison with Trauma-Associated Severe Hemorrhage (TASH) system in predicting the mortality of multiple trauma patients, referred to the hospital emergency department.

METHODS

This follow-up study was conducted on multiple trauma patients (age ≥ 18 years) with Injury Severity Scores (ISS) of ≥ 16, who were referred to the emergency department from March 1, 2017, to December 1, 2017. First, all patients were evaluated based on the Advanced Trauma Life Support (ATLS) guidelines, and then, their blood samples were sent for RDW measurements at baseline and 24 hours after admission. The ISS, Revised Trauma Score (RTS), and TASH were measured in the follow-ups and recorded by third-year emergency medicine residents. Hospital mortality was considered as the outcome of the study.

RESULTS

In this study, 200 out of 535 multiple trauma patients were recruited. The frequency of hospital mortality was 19 (9.5%). In the univariate analysis, there was no significant relationship between hospital mortality and RDW at baseline, RDW on the first day, and ΔRDW (RDW at baseline - RDW on the first day), unlike ISS, RTS, TASH (p=0.97, P= 0.28, and p=0.24, respectively). On the other hand, in the multivariate analysis, ISS, RTS, and TASH showed a significant relationship with hospital mortality. The greatest area under the ROC curve (AUC) was attributed to TASH and RTS systems (0.94 and 0.93, respectively).

CONCLUSION

TASH scoring system, which was mainly designed to predict the need for massive transfusion, may be of prognostic value for hospital mortality in multiple trauma patients, similar to ISS and RTS scoring systems.

Application of a recursive partitioning decision tree algorithm for the prediction of massive transfusion in civilian trauma: the MTPitt prediction tool

BACKGROUND

A supervised machine learning algorithm was used to generate decision trees for the prediction of massive transfusion at a Level 1 trauma center.

METHODS

Trauma patients who received at least one unit of RBCs and/or low-titer group O whole blood between January 1, 2015, and December 31, 2017, were included. Massive transfusion was defined as the transfusion of 10 or more units of RBCs and/or low-titer group O whole blood in the first 24 hours of admission. A recursive partitioning algorithm was used to generate two decision trees for prediction of massive transfusion using a training data set (n = 550): the first, MTPitt, was based on demographic and clinical parameters, and the second, MTPitt+Labs, also included laboratory data. Decision tree performance was compared with the Assessment of Blood Consumption score and the Trauma Associated Severe Hemorrhage score.

RESULTS

The incidence of massive transfusion in the validation data set (n = 199) was 7.5%. The MTPitt decision tree had a higher balanced accuracy (81.4%) and sensitivity (86.7%) compared to an Assessment of Blood Consumption Score of 2 or higher (77.9% and 66.7%, respectively) and a Trauma Associated Severe Hemorrhage score of 9 or higher (75.0% and 73.3%, respectively), although the 95% confidence intervals overlapped. Addition of laboratory data to the MTPitt decision tree (MTPitt+Labs) resulted in a higher specificity and balanced accuracy compared to MTPitt without an increase in sensitivity.

CONCLUSIONS

The MTPitt decisions trees are highly sensitive tools for identifying patients who received a massive transfusion and do not require computational resources to be implemented in the trauma setting.

Massive transfusion triggers in severe trauma: Scoping review

OBJECTIVE

to identify the predictive variables or the massive transfusion triggers in severely traumatized patients through the existing scales.

METHOD

a review of the literature was carried out using the Scoping Review method across the electronic databases CINAHL, MEDLINE, LILACS, the Cochrane and IBECS libraries, and the Google Scholar search tool.

RESULTS

in total, 578 articles were identified in the search and the 36 articles published in the last ten years were included, of which 29 were original articles and 7 review articles. From the analysis, scales for massive transfusion and their predictive triggers were examined.

CONCLUSION

the absence of universal criteria regarding the massive transfusion triggers in traumatized patients has led to the development of different scales, and the studies on their validation are considered relevant for the studies about when to initiate this strategy.

Prediction of massive bleeding in a prehospital setting: validation of six scoring systems

OBJECTIVE

To validate the diagnostic ability of six different scores to predict massive bleeding in a prehospital setting.

DESIGN

Retrospective cohort.

SETTING

Prehospital attention of patients with severe trauma.

SUBJECTS

Subjects with more than 15 years, a history of severe trauma (defined by code 15 criteria), that were initially assisted in a prehospital setting by the emergency services between January 2010 and December 2015 and were then transferred to a level one trauma center in Madrid.

VARIABLES

To validate: 1. Trauma Associated Severe Haemorrhage Score. 2. Assessment of Blood Consumption Score. 3. Emergency Transfusión Score. 4. Índice de Shock. 5. Prince of Wales Hospital/Rainer Score. 6. Larson Score.

RESULTS

548 subjects were studied, 76,8% (420) were male, median age was 38 (interquartile range [IQR]: 27-50). Injury Severity Score was 18 (IQR: 9-29). Blunt trauma represented 82,5% (452) of the cases. Overall, frequency of MB was 9,2% (48), median intensive care unit admission days was 2,1 (IQR: 0,8 - 6,2) and hospital mortality rate was 11,2% (59). Emergency Transfusión Score had the highest precisions (AUC 0,85), followed by Trauma Associated Severe Haemorrhage score and Prince of Wales Hospital/Rainer Score (AUC 0,82); Assessment of Blood Consumption Score was the less precise (AUC 0,68).

CONCLUSION

In the prehospital setting the application of any the six scoring systems predicts the presence of massive hemorrhage and allows the activation of massive transfusion protocols while the patient is transferred to a hospital.

Initiation and Termination of Massive Transfusion Protocols: Current Strategies and Future Prospects

The advent of massive transfusion protocols (MTP) has had a significant positive impact on hemorrhaging trauma patient morbidity and mortality. Nevertheless, societal MTP guidelines and individual MTPs at academic institutions continue to circulate opposing recommendations on topics critical to MTPs. This narrative review discusses up-to-date information on 2 such topics, the initiation and termination of an MTP. The discussion for each begins with a review of the recommendations and supporting literature presented by MTP guidelines from 3 prominent societies, the American Society of Anesthesiologists, the American College of Surgeons, and the task force for Advanced Bleeding Care in Trauma. This is followed by an in-depth analysis of the main components within those recommendations. Societal recommendations on MTP initiation in hemorrhaging trauma patients emphasize the use of retrospectively validated massive transfusion (MT) prediction score, specifically, the Assessment of Blood Consumption and Trauma-Associated Severe Hemorrhage scores. Validation studies have shown that both scoring systems perform similarly. Both scores reliably identify patients that will not require an MT, while simultaneously overpredicting MT requirements. However, each scoring system has its unique advantages and disadvantages, and this review discusses how specific aspects of each scoring system can affect widespread applicability and statistical performance. In addition, we discuss the often overlooked topic of initiating MT in nontrauma patients and the specific tools physicians have to guide the MT initiation decision in this unique setting. Despite the serious complications that can arise with transfusion of large volumes of blood products, there is considerably less research pertinent to the topic of MTP termination. Societal recommendations on MTP termination emphasize applying clinical reasoning to identify patients who have bleeding source control and are adequately resuscitated. This review, however, focuses primarily on the recommendations presented by the Advanced Bleeding Care in Trauma's MTP guidelines that call for prompt termination of the algorithm-guided model of resuscitation and rapidly transitioning into a resuscitation model guided by laboratory test results. We also discuss the evidence in support of laboratory result-guided resuscitation and how recent literature on viscoelastic hemostatic assays, although limited, highlights the potential to achieve additional benefits from this method of resuscitation.

Prehospital identification of trauma patients requiring transfusion: results of a retrospective study evaluating the use of the trauma induced coagulopathy clinical score (TICCS) in 33,385 patients from the TraumaRegister DGU®

BACKGROUND

Identifying trauma patients that need emergent blood product transfusion is crucial. The Trauma Induced Coagulopathy Clinical Score (TICCS) is an easy-to-measure score developed to meet this medical need. We hypothesized that TICCS would assist in identifying patients that need a transfusion in a large cohort of severe trauma patients from the TraumaRegister DGU^® (TR-DGU).

MATERIALS AND METHODS

A total of 33,385 severe trauma patients were extracted from the TR-DGU for retrospective analysis. The TICCS was adapted for the registry structure. Blood transfusion was defined as the use of at least one unit of red blood cells (RBC) during acute hospital treatment.

RESULTS

With an area under the receiving operating curve (AUC) of 0.700 (95% CI: 0.691-0.709), the TICCS appeared to be moderately discriminant for determining the need for RBC transfusion in the trauma population of the TR-DGU. A TICCS cut-off value of ≥12 yielded the best trade-off between true positives and false positives. The corresponding positive predictive value and negative predictive values were 48.4% and 89.1%, respectively.

CONCLUSION

This retrospective study confirms that the TICCS is a useful and simple score for discriminating between trauma patients with and without the need for emergent blood product transfusion.

Early predictors for massive transfusion in older adult severe trauma patients

BACKGROUND

Many scoring systems for the early prediction of the need for massive transfusion (MT) have been reported; in most of these, vital signs are regarded as important. However, the validity of these scoring systems in older patients remains unclear because older trauma patients often present with normal vital signs. In this study, we investigated the effectiveness of previously described scoring systems, as well as risk factors that can provide early prediction of the need for MT in older severe trauma patients.

METHODS

We prospectively collected data from a cohort of severe trauma patients (ISS ≥16 and age ≥16years) admitted from January 2007 to March 2015. Trauma Associated Severe Hemorrhage (TASH), Assessment of Blood Consumption (ABC), and Prince of Wales Hospital (PWH) scores were compared between a younger and an older group. Furthermore, the predictors associated with MT in older severe trauma patients were assessed using multivariable logistic regression analyses.

RESULTS

The area under the curve (AUC) was significantly smaller for older group than for younger group for all three scoring systems (p<0.05). The most important risk factors to predict the need for MT were related to anatomical factors including FAST results (odds ratio (OR): 5.58, 95% confidence interval (CI): 2.10-14.99), unstable pelvic fracture (OR: 21.56, 95% CI: 6.05-90.78), and long bone open fracture of the lower limbs (OR: 12.21, 95% CI: 4.04-39.09), along with pre-injury anticoagulant agent use (OR: 5.22, 95% CI: 1.30-19.61), antiplatelet agent use (OR: 3.81, 95% CI: 1.57-9.04), lactate levels (OR: 1.20, 95% CI: 1.04-1.39) and shock index (OR: 2.67, 95% CI: 1.05-6.84). Traditional vital signs were not early risk factors.

CONCLUSION

We suggest that MT in older trauma patients should be considered on the basis of anatomical factors, pre-injury anticoagulant or antiplatelet agent use, lactate level and SI even if traditional vital signs are normal.

Early Prediction of Ongoing Hemorrhage in Severe Trauma: Presentation of the Existing Scoring Systems

Early prediction of ongoing hemorrhage may reduce mortality via the earlier delivery of blood products, adequate orientation of the patient in a dedicated highly specialized and trained infrastructure, and by earlier correction of acute traumatic coagulopathy. We identified 14 scores or algorithms developed for the prediction of ongoing hemorrhage and the need for massive transfusion in severe trauma patients.

Nomogram to predict perioperative blood transfusion for hepatopancreaticobiliary and colorectal surgery

Background

Predictive tools assessing risk of transfusion have not been evaluated extensively among patients undergoing complex gastrointestinal surgery. In this study preoperative variables associated with blood transfusion were incorporated into a nomogram to predict transfusion following hepatopancreaticobiliary (HPB) or colorectal surgery.

Methods

A nomogram to predict receipt of perioperative transfusion was developed using a cohort of patients who underwent HPB or colorectal surgery between January 2009 and December 2014. The discriminatory ability of the nomogram was tested using the area under the receiver operating characteristic (ROC) curve and internal validation performed via bootstrap resampling.

Results

Among 4961 patients undergoing either a HPB (56·3 per cent) or colorectal (43·7 per cent) resection, a total of 1549 received at least 1 unit of packed red blood cells, giving a perioperative transfusion rate of 31·2 per cent. On multivariable analysis, age 65 years and over (odds ratio (OR) 1·52), race (versus white: black, OR 1·58; Asian, OR 1·86), preoperative haemoglobin 8·0 g/dl or less (versus over 12·0 g/dl: OR 26·79), preoperative international normalized ratio more than 1·2 (OR 2·44), Charlson co-morbidity index score over 3 (OR 1·86) and procedure type (versus colonic surgery: major hepatectomy, OR 1·71; other pancreatectomy, OR 2·12; rectal surgery, OR 1·39; duodenopancreatectomy, OR 2·65) were associated with a significantly higher risk of transfusion and were included in the nomogram. A nomogram was constructed to predict transfusion using these seven variables. Discrimination and calibration of the nomogram revealed good predictive abilities (area under ROC curve 0·756).

Conclusion

The nomogram predicted blood transfusion in major HPB and colorectal surgery.

Relationship between Obesity and Massive Transfusion Needs in Trauma Patients, and Validation of TASH Score in Obese Population: A Retrospective Study on 910 Trauma Patients

Background

Prediction of massive transfusion (MT) is challenging in management of trauma patients. However, MT and its prediction were poorly studied in obese patients. The main objective was to assess the relationship between obesity and MT needs in trauma patients. The secondary objectives were to validate the Trauma Associated Severe Hemorrhage (TASH) score in predicting MT in obese patients and to use a grey zone approach to optimize its ability to predict MT.

Methods and Findings

An observational retrospective study was conducted in a Level I Regional Trauma Center Trauma in obese and non-obese patients. MT was defined as ≥10U of packed red blood cells in the first 24h and obesity as a BMI≥30kg/m². Between January 2008 and December 2012, 119 obese and 791 non-obese trauma patients were included. The rate of MT was 10% (94/910) in the whole population. The MT rate tended to be higher in obese patients than in non-obese patients: 15% (18/119, 95%CI 9‒23%) versus 10% (76/791, 95%CI 8‒12%), OR, 1.68 [95%CI 0.97‒2.92], p = 0.07. After adjusting for Injury Severity Score (ISS), obesity was significantly associated with MT rate (OR, 1.79[95%CI 1.00‒3.21], p = 0.049). The TASH score was higher in the obese group than in the non-obese group: 7(4–11) versus 5(2–10)(p<0.001). The area under the ROC curves of the TASH score in predicting MT was very high and comparable between the obese and non-obese groups: 0.93 (95%CI, 0.89‒0.98) and 0.94 (95%CI, 0.92‒0.96), respectively (p = 0.80). The grey zone ranged respectively from 10 to 13 and from 9 to 12 in obese and non obese patients, and allowed separating patients at low, intermediate or high risk of MT using the TASH score.

Conclusions

Obesity was associated with a higher rate of MT in trauma patients. The predictive performance of the TASH score and the grey zones were robust and comparable between obese and non-obese patients.

Prediction of critical haemorrhage following trauma: A narrative review

Introduction: Traumatic haemorrhagic shock can be difficult to diagnose. Models for predicting critical bleeding and massive transfusion have been developed to aid clinicians. The aim of this review is to outline the various available models and report on their performance and validation. Methods: A review of the English and non-English literature in Medline, PubMed and Google Scholar was conducted from 1990 to September 2015. We combined several terms for i) haemorrhage AND ii) prediction, in the setting of iii) trauma. We included models that had at least two data points. We extracted information about the models, their developments, performance and validation. Results: There were 36 different models identified that diagnose critical bleeding, which included a total of 36 unique variables. All models were developed retrospectively. The models performed with variable predictive abilities–the most superior with an area under the receiver operating characteristics curve of 0.985, but included detailed findings on imaging and was based on a small cohort. The most commonly included variable was systolic blood pressure, featuring in all but five models. Pattern or mechanism of injury were used by 16 models. Pathology results were used by 15 models, of which nine included base deficit and eight models included haemoglobin. Imaging was utilised in eight models. Thirteen models were known to be validated, with only one being prospectively validated. Conclusions: Several models for predicting critical bleeding exist, however none were deemed accurate enough to dictate treatment. Potential areas of improvement identified include measures of variability in vital signs and point of care imaging and pathology testing.

[Multidisciplinary consensus document on the management of massive haemorrhage (HEMOMAS document)]

Massive haemorrhage is common and often associated with high morbidity and mortality. We perform a systematic review of the literature, with extraction of the recommendations from the existing evidences because of the need for its improvement and the management standardization. From the results we found, we wrote a multidisciplinary consensus document. We begin with the agreement in the definitions of massive haemorrhage and massive transfusion, and we do structured recommendations on their general management (clinical assessment of bleeding, hypothermia management, fluid therapy, hypotensive resuscitation and damage control surgery), blood volume monitoring, blood products transfusion (red blood cells, fresh frozen plasma, platelets and their best transfusion ratio), and administration of hemostatic components (prothrombin complex, fibrinogen, factor VIIa, antifibrinolytic agents).

Multidisciplinary consensus document on the management of massive haemorrhage (HEMOMAS document)

Massive haemorrhage is common and often associated with high morbidity and mortality. We perform a systematic review of the literature, with extraction of the recommendations from the existing evidences because of the need for its improvement and the management standardization. From the results we found, we wrote a multidisciplinary consensus document. We begin with the agreement in the definitions of massive haemorrhage and massive transfusion, and we do structured recommendations on their general management (clinical assessment of bleeding, hypothermia management, fluid therapy, hypotensive resuscitation and damage control surgery), blood volume monitoring, blood products transfusion (red blood cells, fresh frozen plasma, platelets and their best transfusion ratio), and administration of hemostatic components (prothrombin complex, fibrinogen, factor VIIa, antifibrinolytic agents).

Diversity in clinical management and protocols for the treatment of major bleeding trauma patients across European level I Trauma Centres

Background

Uncontrolled haemorrhage is still the leading cause of preventable death after trauma and the primary focus of any treatment strategy should be related to early detection and control of blood loss including haemostasis.

Methods

For assessing management practices across six European level I trauma centres with academic interest and research in the field of coagulopathy an online survey was conducted addressing local management practice for bleeding trauma patients including algorithms for detection, management and monitoring coagulation disorders and immediate interventions. Each centre provided their locally applied massive transfusion protocol.

Results

All participating trauma centres have developed and implemented a local algorithm and protocol for the bleeding trauma patient. These are uniformly activated by clinical triggers and deactivated once the bleeding has stopped according to clinical assessment in combination with laboratory signs of achieved haemostasis. The severity of coagulopathy and shock is mostly assessed via standard coagulation tests and partially used extended viscoelastic tests. All centres have implemented the immediate use of tranexamic acid. Initial resuscitation is started either pre-hospital or after hospital admission by using transfusion packages with pre-fixed universal blood product combinations and ratios following the concept of “damage control resuscitation” at which applied ratios substantially vary. Two centres initially start with transfusion packages but with viscoelastic tests running in parallel to quickly allow a shift towards a viscoelastic test-guided therapy.

Conclusion

Diversity in the management of bleeding trauma patients such as pre-hospital blood administration and routinely performed viscoelastic tests exists even among level I trauma centres. The paucity of consensus among these centres highlights the need for further primary research followed by clinical trials to improve the evidence for sophisticated guidelines and strategies.

Electronic supplementary material

The online version of this article (doi:10.1186/s13049-015-0147-6) contains supplementary material, which is available to authorized users.

Massive transfusion prediction with inclusion of the pre-hospital Shock Index

BACKGROUND

Detecting occult bleeding can be challenging and may delay resuscitation. The Shock Index (SI) defined as heart rate divided by systolic blood pressure has attracted attention. Prediction models using combinations of pre-hospital SI (phSI) and the trauma centre SI (tcSI) values may be effective in identifying patients requiring massive blood transfusions (MT).

AIM

To explore whether combinations of the phSI and the tcSI augment MT prediction.

METHODS

The scores were retrospectively developed using all major trauma patients that presented to The Alfred Hospital between 2006 and 2012. The first PH and TC observations were used. To avoid exclusion of the 'sickest' patients, the SI was imputed to 2 where SBP was missing, but HR was present. We developed 4 models. (i) 'Dichotomised', defined as positive when both phSI and tcSI were ≥1. (ii) 'Formulaic', defined by logistic regression analysis. (iii) 'Combination', defined pragmatically based on the logistic regression. (iv) 'Trending', defined as: tcSI minus phSI.

RESULTS

There were 6990 major trauma patients and 360 (5.2%) received MT. There were 1371 cases with either phSI or tcSI missing and were thus excluded from the analysis. The 'Dichotomised' had higher positive predictive value than the tcSI with a further 5 per 100 patients identified. The 'Formulaic' model, defined as: log Odds (MT)=2.16×tcSI+0.89×phSI-5.42, and the 'Combination' model, defined as: phSI×0.5+tcSI, performed equally (AUROC 0.83 versus 0.83, χ(2)=0.86, p=0.35). The 'Formulaic' performed marginally, but statistically significantly, more accurate than the tcSI alone (AUROC 0.83 versus 0.82, χ(2)=6.89, p<0.01). An 'Upward Trending' SI was observed in 1758 patients, revealing a 4.6-fold univariate association with MT (OR 4.55; 95%CI 2.64-7.83), and an AUROC of 0.79 (95%CI 0.74-0.83). The 'Downward Trending' SI was protective against MT (OR 0.44; 95%CI 0.34-0.57).

CONCLUSION

The initial pre-hospital SI is associated with MT. However, this relationship did not clinically augment MT decision when combined with the in-hospital SI. The simplicity of the SI makes it a favourable option to explore further. Computer-assisted technology in data capturing, analysis and prognostication presents avenues for further research.

Clinical gestalt and the prediction of massive transfusion after trauma

INTRODUCTION

Early recognition and treatment of trauma patients requiring massive transfusion (MT) has been shown to reduce mortality. While many risk factors predicting MT have been demonstrated, there is no universally accepted method or algorithm to identify these patients. We hypothesised that even among experienced trauma surgeons, the clinical gestalt of identifying patients who will require MT is unreliable.

METHODS

Transfusion and mortality outcomes after trauma were observed at 10 U.S. Level-1 trauma centres in patients who survived ≥ 30 min after admission and received ≥ 1 unit of RBC within 6h of arrival. Subjects who received ≥ 10 units within 24h of admission were classified as MT patients. Trauma surgeons were asked the clinical gestalt question "Is the patient likely to be massively transfused?" 10 min after the patients arrival. The performance of clinical gestalt to predict MT was assessed using chi-square tests and ROC analysis to compare gestalt to previously described scoring systems.

RESULTS

Of the 1245 patients enrolled, 966 met inclusion criteria and 221 (23%) patients received MT. 415 (43%) were predicted to have a MT and 551(57%) were predicted to not have MT. Patients predicted to have MT were younger, more often sustained penetrating trauma, had higher ISS scores, higher heart rates, and lower systolic blood pressures (all p<0.05). Gestalt sensitivity was 65.6% and specificity was 63.8%. PPV and NPV were 34.9% and 86.2% respectively.

CONCLUSION

Data from this large multicenter trial demonstrates that predicting the need for MT continues to be a challenge. Because of the increased mortality associated with delayed therapy, a more reliable algorithm is needed to identify and treat these severely injured patients earlier.

Indications for blood transfusion following trauma - a pilot study

Background: Indications for blood transfusion during trauma resuscitation remain poorly understood. This study aimed to objectively determine the range of factors that lead to initiation of blood transfusion during trauma resuscitation. Design and method: This was a prospective, observational pilot study. A questionnaire was distributed to all clinicians following any transfusion of packed red blood cells during trauma resuscitation. The questionnaire focused on the clinicians’ opinion regarding the indication for red cell transfusion. Results: Complete data on 37 individual episodes of transfusion initiation in the Emergency Department were collected. The most commonly used pre-hospital factors that influenced initiation of transfusion was a pre-hospital systolic blood pressure (SBP) of < 100 mm Hg (65%), pre-hospital tachycardia (38%) or estimated blood loss of >1 L (30%) by paramedics. On arrival to hospital, the activation of a massive transfusion protocol was the commonest indication for transfusion, followed by a positive FAST examination (43%), low systolic blood pressure (35%), tachycardia (32%) or pallor (35%). Blood tests to guide initiation of transfusion were less commonly used with 9 (24%) patients transfused for a low haemoglobin level and 6 (16%) patients transfused for coagulopathy. Conclusions: A combination of objective pre- and in-hospital vital signs, together with subjective indicators such as pallor and estimation of blood loss guided initiation of transfusion following injury.

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.

A simple assessment of haemothoraces thickness predicts abundant transfusion: a series of 525 blunt trauma patients

BACKGROUND

The goal of this study was to evaluate the performance of haemothorax quantification to predict an abundant transfusion in blunt thoracic trauma patients.

METHODS

This study included all severe trauma patients admitted into our trauma centre from January 2005 to January 2010, who presented a blunt thoracic trauma (thoracic AIS ≥1) and had a CT scan within the first hour following admission. For each haemothorax, thickness of dominant side and the cumulated thicknesses of both sides (Dominant-t, Cumulated-t), as well as lengths (Dominant-l, Cumulated-l) and the calculated volumes (Dominant-v, Cumulated-v provided by a previously validated formula) were retrospectively measured by CT scan. A multiple logistic regression was performed to define the independent risk factors for an abundant transfusion (≥5 packed red blood cells in the first 24h). Finally, ROC curves have been drawn on an isolated thoracic trauma subgroup to predict abundant transfusion. The more specific cut-offs were extracted from this analysis.

RESULTS

From the 525 blunt thoracic trauma patients (75% males, mean age 38.2 (SD18.7) years, mean ISS 22.5 (SD16.4)), 31% received an abundant transfusion. In multivariable analysis, Cumulated-t was significantly associated with an abundant transfusion (OR 1.3 [95% CI 1.1-1.4], P=0.002). In isolated thoracic trauma subgroup (n=251), the global abilities of different CT measurements to predict abundant transfusion were significantly comparable (AUCs 0.69-0.70). The more specific cut-offs were established at 28mm for Cumulated-t (specificity 92%, positive predictive value 47%) and at 24mm for Dominant-t (specificity 92%; positive predictive value 43%).

CONCLUSION

The haemothorax quantification upon admission may help to predict transfusion needs. Cumulated-t was found independent risk factor for abundant transfusion in a large population of severe trauma patients. Beyond a Cumulated-t of 28mm or a Dominant-t of 24mm, abundant transfusion will be very frequently necessary.

LEVEL OF EVIDENCE

Retrospective review, level III.

Acute traumatic coagulopathy in the setting of isolated traumatic brain injury: Definition, incidence and outcomes

BACKGROUND AND OBJECTIVES

Acute traumatic coagulopathy (ATC) has been reported in the setting of isolated traumatic brain injury (iTBI) and associated with poor outcomes. Among patients with iTBI, we aimed to select an appropriate definition of ATC, outline the incidence of ATC and examine clinical variables associated with ATC.

METHODS

A retrospective review of The Alfred Trauma Registry was conducted and patients with iTBI (head AIS [Abbreviated Injury Score] ≥ 3 and all other body regions AIS < 3) were selected for analysis. The association of the international normalised ratio (INR) on arrival at hospital with the mortality on hospital discharge was explored, to select an appropriate clinical horizon to define ATC. The incidence of ATC was calculated using this definition. Injury and clinical variables measurable pre-hospital and immediately on arrival at the hospital were analysed to determine independent associations with ATC.

RESULTS

There were 1718 patients with iTBI included in the study. The overall mortality was 12%, but significantly greater when initial INR was measured at ≥ 1.3 (45.1%; p < 0.01). The proportion of patients with ATC, using this definition, was 7.7% (95% CI: 6.5-9.0). The pre-hospital variables independently associated with ATC in the setting of iTBI were age (OR 1.02, 95% CI 1.01-1.03), shock index (SI) of ≥ 1 (OR 1.68, 95% CI 1.01-2.79) and abnormal pupils (OR 8.33, 95% CI 4.50-15.89). The presence of at least two factors, of age > 50 yrs, SI ≥ 1, or abnormal pupils, was 97.54% (95% CI: 96.6-98.2) specific for ATC.

CONCLUSIONS

An abnormal initial INR in the setting of iTBI was associated with poor outcomes, regardless of magnitude. The incidence of ATC appears too low to recommend empiric pro-coagulant management for all patients with iTBI. The subgroup of patients older than 50 yrs., with shock or abnormal size of pupils, may be considered for interventional trials of early treatment against ATC.

Triaging the right patient to the right place in the shortest time

Trauma systems have been successful in saving lives and preventing disability. Making sure that the right patient gets the right treatment in the shortest possible time is integral to this success. Most trauma systems have not fully developed trauma triage to optimize outcomes. For trauma triage to be effective, there must be a well-developed pre-hospital system with an efficient dispatch system and adequately resourced ambulance system. Hospitals must have clear designations of the level of service provided and agreed protocols for reception of patients. The response within the hospital must be targeted to ensure the sickest patients get an immediate response. To enable the most appropriate response to trauma patients across the system, a well-developed monitoring programme must be in place to ensure constant refinement of the clinical response. This article gives a brief overview of the current approach to triaging trauma from time of dispatch to definitive treatment.

Predicting red blood cell transfusion in hospitalized patients: role of hemoglobin level, comorbidities, and illness severity

Background

Randomized controlled trial evidence supports a restrictive strategy of red blood cell (RBC) transfusion, but significant variation in clinical transfusion practice persists. Patient characteristics other than hemoglobin levels may influence the decision to transfuse RBCs and explain some of this variation. Our objective was to evaluate the role of patient comorbidities and severity of illness in predicting inpatient red blood cell transfusion events.

Methods

We developed a predictive model of inpatient RBC transfusion using comprehensive electronic medical record (EMR) data from 21 hospitals over a four year period (2008-2011). Using a retrospective cohort study design, we modeled predictors of transfusion events within 24 hours of hospital admission and throughout the entire hospitalization. Model predictors included administrative data (age, sex, comorbid conditions, admission type, and admission diagnosis), admission hemoglobin, severity of illness, prior inpatient RBC transfusion, admission ward, and hospital.

Results

The study cohort included 275,874 patients who experienced 444,969 hospitalizations. The 24 hour and overall inpatient RBC transfusion rates were 7.2% and 13.9%, respectively. A predictive model for transfusion within 24 hours of hospital admission had a C-statistic of 0.928 and pseudo-R2 of 0.542; corresponding values for the model examining transfusion through the entire hospitalization were 0.872 and 0.437. Inclusion of the admission hemoglobin resulted in the greatest improvement in model performance relative to patient comorbidities and severity of illness.

Conclusions

Data from electronic medical records at the time of admission predicts with very high likelihood the incidence of red blood transfusion events in the first 24 hours and throughout hospitalization. Patient comorbidities and severity of illness on admission play a small role in predicting the likelihood of RBC transfusion relative to the admission hemoglobin.

Fibrinolysis greater than 3% is the critical value for initiation of antifibrinolytic therapy

BACKGROUND

The acute coagulopathy of trauma is present in up to one third of patients by the time of admission, and the recent CRASH-2 and MATTERs trials have focused worldwide attention on hyperfibrinolysis as a component of acute coagulopathy of trauma. Thromboelastography (TEG) is a powerful tool for analyzing fibrinolyis, but a clinically relevant threshold for defining hyperfibrinolysis has yet to be determined. Recent data suggest that the accepted normal upper bound of 7.5% for 30-minute fibrinolysis (LY30) by TEG is inappropriate in severe trauma, as the risk of death rises at much lower levels of clot lysis. We wished to determine the validity of this hypothesis and establish a threshold value to treat fibrinolysis, based on prediction of massive transfusion requirement and risk of mortality.

METHODS

Patients with uncontrolled hemorrhage, meeting the massive transfusion protocol (MTP) criteria at admission (n = 73), represent the most severely injured trauma population at our center (median Injury Severity Score [ISS], 30; interquartile range, 20-38). Citrated kaolin TEG was performed at admission blood samples from this population, stratified by LY30, and evaluated for transfusion requirement and 28-day mortality. The same analysis was conducted on available field blood samples from all non-MTP trauma patients (n = 216) in the same period. These represent the general trauma population.

RESULTS

Within the MTP-activating population, the cohort of patients with LY30 of 3% or greater was shown to be at much higher risk for requiring a massive transfusion (90.9% vs. 30.5%, p = 0.0008) and dying of hemorrhage (45.5% vs. 4.8%, p = 0.0014) than those with LY30 less than 3%. Similar trends were seen in the general trauma population.

CONCLUSION

LY30 of 3% or greater defines clinically relevant hyperfibrinolysis and strongly predicts the requirement for massive transfusion and an increased risk of mortality in trauma patients presenting with uncontrolled hemorrhage. This threshold value for LY30 represents a critical indication for the treatment of fibrinolysis.

LEVEL OF EVIDENCE

Prognostic study, level III.

The utility of a shock index ≥ 1 as an indication for pre-hospital oxygen carrier administration in major trauma

INTRODUCTION AND AIMS

The use of intravenous oxygen carriers (packed red blood cells (PRBC), whole blood and synthetic haemoglobins (HBOCs) for selected pre-hospital trauma resuscitation cases has been reported, despite a lack of validated clinical indications. The aim of this study was to retrospectively identify a sub-group of adult major trauma patients most likely to benefit from pre-hospital oxygen carrier administration and determine the predictive relationship between pre-hospital shock index (SI) [pulse rate/systolic blood pressure] and haemorrhagic shock, blood transfusion and mortality.

METHODS

A retrospective review of adult major trauma patients recorded in The Alfred Trauma Registry was conducted. Patients were included if they received at least 1L of pre-hospital crystalloid and spent over 30 min in transit. The association of shock index and transfusion was determined. Patients were further sub-grouped by mode of transport to determine the population of trauma patients who could be included into prospective studies of intravenous oxygen carriers.

RESULTS

There were 1149 patients included of whom 311 (21.9%) received an acute blood transfusion. The SI correlated well with transfusion practice. A SI ≥ 1.0, calculated after at least 1L of crystalloid transfusion, identified patients with a high specificity (93.5%; 95% CI: 91.8-94.8) for receiving a blood transfusion within 4h of hospital arrival. While patients transported by helicopter had higher injury severity and blood transfusion requirement, there were no difference in physiological variables and outcomes when compared to patients transported by road car.

CONCLUSIONS

A shock index ≥ 1.0 is an easily calculated variable that may identify patients for inclusion into trials for pre-hospital oxygen carriers. Shocked patients have high mortality rates whether transported by road car or by helicopter. The efficacy of pre-hospital intravenous oxygen carriers should be trialled using a shock index ≥ 1.0 despite fluid resuscitation as the clinical trigger for administration.

Identifying the bleeding trauma patient: predictive factors for massive transfusion in an Australasian trauma population

BACKGROUND

Military and civilian data would suggest that hemostatic resuscitation results in improved outcomes for exsanguinating patients. However, identification of those patients who are at risk of significant hemorrhage is not clearly defined. We attempted to identify factors that would predict the need for massive transfusion (MT) in an Australasian trauma population, by comparing those trauma patients who did receive massive transfusion with those who did not.

METHODS

Between 1985 and 2010, 1,686 trauma patients receiving at least 1 U of packed red blood cells were identified from our prospectively maintained trauma registry. Demographic, physiologic, laboratory, injury, and outcome variables were reviewed. Univariate analysis determined significant factors between those who received MT and those who did not. A predictive multivariate logistic regression model with backward conditional stepwise elimination was used for MT risk. Statistical analysis was performed using SPSS PASW.

RESULTS

MT patients had a higher pulse rate, lower Glasgow Coma Scale (GCS) score, lower systolic blood pressure, lower hemoglobin level, higher Injury Severity Score (ISS), higher international normalized ratio (INR), and longer stay. Initial logistic regression identified base deficit (BD), INR, and hemoperitoneum at laparotomy as independent predictive variables. After assigning cutoff points of BD being greater than 5 and an INR of 1.5 or greater, a further model was created. A BD greater than 5 and either INR of 1.5 or greater or hemoperitoneum was associated with 51 times increase in MT risk (odds ratio, 51.6; 95% confidence interval, 24.9-95.8). The area under the receiver operating characteristic curve for the model was 0.859.

CONCLUSION

From this study, a combination of BD, INR, and hemoperitoneum has demonstrated good predictability for MT. This tool may assist in the determination of those patients who might benefit from hemostatic resuscitation.

LEVEL OF EVIDENCE

Prognostic study, level III.

The initial management of severe trauma patients at hospital admission

The initial management of trauma patient is a critical period aiming at: stabilizing the vital functions; following a rigorous injury assessment; defining a therapeutic strategy. This management has to be organized to minimize loss of time that would be deleterious for the patients outcome. Thus, before patient arrival, the trauma team alert should lead to the initiation of care procedures adapted to the announced severity of the patient. Moreover, each individual should know its role in advance and the team should be managed by only one individual (the trauma leader) to avoid conflicts of decision. A rapid trauma injury assessment aims not only at guiding resuscitation (chest drainage, pelvic contention, to define the mean arterial pressure goal) but also to decide a critical intervention in case of hemodynamic instability (laparotomy, thoracotomy, arterial embolisation). This initial assessment includes a chest and a pelvic X-ray, abdominal ultrasound (extended to the lung) and transcranial Doppler (TCD). The whole body scanner with administration of intravenous contrast material is the cornerstone of the injury assessment but can be done for patients stabilized after the initial resuscitation.

[Current trends in plasma transfusion for patients with severe hemorrhage]

Recent changes in plasma transfusion practices for severe hemorrhage are largely related to the recognition of an early endogenous coagulopathy associated with traumatic injury. Observational and mostly retrospective data suggest improved survival rates with high-dose plasma therapy, up to a 1:1 ratio of fresh frozen plasma to packed red blood cells, but the quality of evidence is limited. Putting it into practice raises many issues (early identification of patients at risk of massive bleeding, extrapolation to non-trauma settings, alternative or adjunctive treatments, among others) that are discussed in this brief review.

Hemoperitoneum semiquantitative analysis on admission of blunt trauma patients improves the prediction of massive transfusion

BACKGROUND

The purpose of this study was to define whether the semiquantitative analysis of hemoperitoneum increases the accuracy of early prediction of massive transfusion (MT).

METHODS

A retrospective review of severe trauma patients consecutively admitted to our trauma intensive care unit between January 2005 and December 2009 was conducted. Patients diagnosed with blunt abdominal trauma who had a computed tomography scan on admission were included. The hemoperitoneum size was defined using the Federle score on computed tomography as large, moderate, or minimal/none. The association between MT (≥10 U of packed red blood cells in the first 24 h) and moderate and large sizes of hemoperitoneum was assessed using a multiple logistic model.

RESULTS

Of the 381 patients meeting the inclusion criteria, 270 (71%) were male; the mean age was 35.5 ± 18.2 years and mean injury severity score was 23.4 ± 17. Ninety-seven (26%) had large hemoperitoneum, 107 (28%) had moderate hemoperitoneum, and 177 (46%) had minimal/no hemoperitoneum. Eighty-three patients (22%) required MT. The positive predictive value for MT of a large hemoperitoneum was 41%, 23% for a moderate hemoperitoneum, and 10% for minimal/no hemoperitoneum (P < .001). The corresponding values for hypotensive patients were 61%, 32%, and 25%, respectively (P < .001). In the multivariate analysis model, only the large size of hemoperitoneum was significantly associated with MT (OR 6.4, 95% CI 2.9-14, P < .001, r(2) = 0.47).

CONCLUSION

The assessment of the size of hemoperitoneum on admission substantially improves the prediction of MT in trauma patients and should be used to trigger and guide initial haemostatic resuscitation.