An International Normalized Ratio-Based Definition of Acute Traumatic Coagulopathy Is Associated With Mortality, Venous Thromboembolism, and Multiple Organ Failure After Injury

In vitro evaluation of a new viscoelastometry-based point-of-care analyzer

INTRODUCTION

The VCM is a point-of-care analyzer using a new viscoelastometry technique for rapid assessment of hemostasis on fresh whole blood. Its characteristics would make it suitable for use in austere environments. The purpose of this study was to evaluate the VCM in terms of repeatability, reproducibility and interanalyzer correlation, reference values in our population, correlation with standard coagulation assays and platelet count, correlation with the TEG5000 analyzer and resistance to stress conditions mimicking an austere environment.

METHODS

Repeatability, reproducibility, and interanalyzer correlation were performed on quality control samples (n = 10). Reference values were determined from blood donor samples (n = 60). Correlations with standard biological assays were assessed from ICU patients (n = 30) and blood donors (n = 60) samples. Correlation with the TEG5000 was assessed from blood donor samples. Evaluation of vibration resistance was performed on blood donor (n = 5) and quality control (n = 5) samples.

RESULTS

The CVs for repeatability and reproducibility ranged from 0% to 11%. Interanalyzer correlation found correlation coefficients (r2) ranging from 0.927 to 0.997. Our reference values were consistent with those provided by the manufacturer. No robust correlation was found with conventional coagulation tests. The correlation with the TEG5000 was excellent with r2 ranging from 0.75 to 0.92. Resistance to stress conditions was excellent.

CONCLUSION

The VCM analyzer is a reliable, easy-to-use instrument that correlates well with the TEG5000. Despite some logistical constraints, the results suggest that it can be used in austere environments. Further studies are required before its implementation.

Blood Transfusion for Major Trauma in Emergency Department

Severe bleeding is the leading cause of death in patients with major trauma admitted to the emergency department. It is estimated that about 50% of deaths happen within a few minutes of the traumatic event due to massive hemorrhage; 30% of deaths are related to neurological dysfunction and typically happen within two days of trauma; and approximately 20% of patients died of multiorgan failure and sepsis within days to weeks of the traumatic event. Over the past ten years, there has been an increased understanding of the underlying mechanisms and pathophysiology associated with traumatic bleeding leading to improved management measures. Traumatic events cause significant tissue damage, with the potential for severe blood loss and the release of cytokines and hormones. They are responsible for systemic inflammation, activation of fibrinolysis pathways, and consumption of coagulation factors. As the final results of this (more complex in real life) cascade, patients can develop tissue hypoxia, acidosis, hypothermia, and severe coagulopathy, resulting in a rapid deterioration of general conditions with a high risk of mortality. Prompt and appropriate management of massive bleeding and coagulopathy in patients with trauma remains a significant challenge for emergency physicians in their daily clinical practice. Our review aims to explore literature studies providing evidence on the treatment of hemorrhage with blood support in patients with trauma admitted to the Emergency Department with a high risk of death. Advances in blood transfusion protocols, along with improvements in other resuscitation strategies, have become one of the most important issues to face and a key topic of recent clinical research in this field.

The Utilisation of INR to identify coagulopathy in burn patients

Studies conflict on the significance of burn-induced coagulopathy. We posit that burn-induced coagulopathy is associated with injury severity in burns. Our purpose was to characterize coagulopathy profiles in burns and determine relationships between % total burn surface area (TBSA) burned and coagulopathy using the International Normalized Ratio (INR). Burned patients with INR values were identified in the TriNetX database and analyzed by %TBSA burned. Patients with history of transfusions, chronic hepatic failure, and those on anticoagulant medications were excluded. Interquartile ranges for INR in the burned study population were 1.2 (1.0-1.4). An INR of ≥ 1.5 was used to represent those with burn-induced coagulopathy as it fell outside the 3rd quartile. The population was stratified into subgroups using INR levels <1.5 or ≥1.5 on the day of injury. Data are average ± SD analyzed using chi-square; p < .05 was considered significant. There were 7,364 burned patients identified with INR <1.5, and 635 had INR ≥1.5. Comparing TBSA burned groups, burn-induced coagulopathy significantly increased in those with ≥20% TBSA; p = .048 at 20-29% TBSA, p = .0005 at 30-39% TBSA, and p < .0001 for 40% TBSA and above. Age played a significant factor with average age for those with burn-induced coagulopathy 59 ± 21.5 years and 46 ± 21.8 for those without (p < .0001). After matching for age, TBSA, and demographics, the risk of 28 day-mortality was higher in those with burn-induced coagulopathy compared to those without (risk difference 20.9%, p < .0001) and the odd ratio with 95% CI is 4.45 (3.399-5.825). Investigation of conditions associated with burn-induced coagulopathy showed the effect of heart diseases to be significant; 53% of patients with burn-induced coagulopathy had hypertension (p < .0001). Burn-induced coagulopathy increases with %TBSA burned. The information gained firmly reflects a link between %TBSA and burn-induced coagulopathy, which could be useful in prognosis and treatment decisions.

Hepatocellular Carcinoma: The Role of Surgery in Liver Cirrhosis

Background

Liver surgery is an essential component of hepatocellular carcinoma (HCC) treatment. Advances in surgical techniques and perioperative care have improved outcomes and have helped to expand surgical indications. However, liver fibrosis and cirrhosis still remain major problems for liver surgery due to the relevant impact on liver regeneration of the future liver remnant (FLR) after surgery. Especially in patients with clinically significant portal hypertension due to liver cirrhosis, surgery is limited. Despite recent efforts in developing predictive models, estimating the postoperative hepatic function remains difficult.

Summary

In this review, we focus on the role of surgery in the treatment of HCC in structurally altered livers. The importance of assessing FLR with techniques such as contrast-enhanced CT, e.g., with the help of artificial intelligence is highlighted. Moreover, strategies for increasing the FLR with approaches like portal vein embolization and liver vein deprivation prior to surgery are discussed. Patient selection, minimally invasive liver surgery including robotic techniques, and perioperative concepts like the Enhanced Recovery After Surgery (ERAS) guidelines are identified as crucial parts of avoiding posthepatectomy liver failure.

Key Message

The need for ongoing research to optimize patient selection criteria and perioperative care and to develop innovative biomarkers for outcome prediction is emphasized.

The nature and timing of coagulation dysfunction in a cohort of trauma patients in the Australian pre-hospital setting

BACKGROUND

Acute Traumatic Coagulopathy (ATC) is a complex pathological process that is associated with patient mortality and increased blood transfusion requirements. It is evident on hospital arrival, but there is a paucity of information about the nature of ATC and the characteristics of patients that develop ATC in the pre-hospital setting. The objective of this study was to describe the nature and timing of coagulation dysfunction in a cohort of injured patients and to report on patient and pre-hospital factors associated with the development of ATC in the field.

METHODS

This was a prospective observational study of a convenience sample of trauma patients. Patients had blood taken during the pre-hospital phase of care and evaluated for derangements in Conventional Coagulation Assays (CCA) and Rotational Thromboelastometry (ROTEM). Associations between coagulation derangement and pre-hospital factors and patient outcomes were evaluated.

RESULTS

A total of 216 patients who had either a complete CCA or ROTEM were included in the analysis. One hundred and eighty (83 %) of patients were male, with a median injury severity score of 17 [interquartile range (IQR) 10-27] and median age of 34 years [IQR = 25.0-52.0]. Hypofibrinogenemia was the predominant abnormality seen, (CCA Hypofibrinogenemia: 51/193, 26 %; ROTEM hypofibrinogenemia: 65/204, 32 %). Increased CCA derangement, the presence of ROTEM coagulopathy, worsening INR, worsening FibTEM and decreasing fibrinogen concentration, were all associated with both mortality and early massive transfusion.

CONCLUSION

Clinically significant, multifaceted coagulopathy develops early in the clinical course, with hypofibrinogenemia being the predominant coagulopathy. In keeping with the ED literature, pre-hospital coagulation dysfunction was associated with mortality and early massive transfusion. Further work is required to identify strategies to identify and guide the pre-hospital management of the coagulation dysfunction seen in trauma.

Tissue plasminogen activator challenge thrombelastography is the most accurate assay in predicting the need for massive transfusion in hypotensive trauma patients

BACKGROUND

Tissue plasminogen activator (tPA) added to thrombelastography (TEG) detects hyperfibrinolysis by measuring clot lysis at 30 min (tPA-challenge-TEG). We hypothesize that tPA-challenge-TEG is a better predictor of massive transfusion (MT) than existing strategies in trauma patients with hypotension.

METHODS

Trauma activation patients (TAP, 2014-2020) with 1) systolic blood pressure <90 mmHg (early) or 2) those who arrived normotensive but developed hypotension within 1H postinjury (delayed) were analyzed. MT was defined as >10 RBC U/6H postinjury or death within 6H after ≥1 RBC unit. Area under the receiver operating characteristics curves were used to compare predictive performance. Youden index determined optimal cutoffs.

RESULTS

tPA-challenge-TEG was the best predictor of MT in the early hypotension subgroup (N = 212) with positive (PPV) and negative predictive values (NPV) of 75.0%, and 77.6%, respectively. tPA-challenge-TEG was a better predictor of MT than all but TASH (PPV = 65.0%, NPV = 93.3%) in the delayed hypotension group (N = 125).

CONCLUSIONS

The tPA-challenge-TEG is the most accurate predictor of MT in trauma patients arriving hypotensive and offers early recognition of MT in patients with delayed hypotension.

The prognostic value of an age-adjusted BIG score in adult patients with traumatic brain injury

Background

The base deficit, international normalized ratio, and Glasgow Coma Scale (BIG) score was previously developed to predict the outcomes of pediatric trauma patients. We designed this study to explore and improve the prognostic value of the BIG score in adult patients with traumatic brain injury (TBI).

Methods

Adult patients diagnosed with TBI in a public critical care database were included in this observational study. The BIG score was calculated based on the Glasgow Coma Scale (GCS), the international normalized ratio (INR), and the base deficit. Logistic regression analysis was performed to confirm the association between the BIG score and the outcome of included patients. Receiver operating characteristic (ROC) curves were drawn to evaluate the prognostic value of the BIG score and novel constructed models.

Results

In total, 1,034 TBI patients were included in this study with a mortality of 22.8%. Non-survivors had higher BIG scores than survivors (p < 0.001). The results of multivariable logistic regression analysis showed that age (p < 0.001), pulse oxygen saturation (SpO2) (p = 0.032), glucose (p = 0.015), hemoglobin (p = 0.047), BIG score (p < 0.001), subarachnoid hemorrhage (p = 0.013), and intracerebral hematoma (p = 0.001) were associated with in-hospital mortality of included patients. The AUC (area under the ROC curves) of the BIG score was 0.669, which was not as high as in previous pediatric trauma cohorts. However, combining the BIG score with age increased the AUC to 0.764. The prognostic model composed of significant factors including BIG had the highest AUC of 0.786.

Conclusion

The age-adjusted BIG score is superior to the original BIG score in predicting mortality of adult TBI patients. The prognostic model incorporating the BIG score is beneficial for clinicians, aiding them in making early triage and treatment decisions in adult TBI patients.

Trends in massive transfusion practice for trauma in Japan from 2011 to 2020: a nationwide inpatient database study

BACKGROUND

Previous studies have reported conflicting results regarding fresh frozen plasma (FFP)-to-red blood cell (RBC) ratio and platelet-to-RBC ratio on outcomes for massive transfusion for trauma. Moreover, nationwide data on massive transfusion practices for trauma in the real-world clinical setting are scarce. This study aimed to examine the nationwide practice patterns and trends in massive transfusion for trauma in Japan using a national administrative, inpatient database.

METHOD

We identified patients who underwent emergency hospitalization for trauma and received massive transfusion, defined as administration of at least 20 units of RBC within the first 2 days of admission, using the nationwide inpatient database, which covers approximately 90% of all tertiary emergency hospitals in Japan, between 2011 and 2020. Trends in the incidence and practice patterns of massive transfusion were described by calendar year. The association of practice patterns with mortality or adverse events was tested.

RESULTS

A total of 3,530,846 trauma hospitalizations were identified, of which 5247 (0.15%) received massive transfusion. A significant declining trend was observed in the incidence of massive transfusion in trauma hospitalizations from 0.24% in 2011 to 0.10% in 2020 (P for trend < 0.001). The FFP-to-RBC ratio rose significantly from 0.77 in 2011 to 1.08 in 2020 (P for trend < 0.001), while the platelet-to-RBC ratio remained virtually unchanged from 0.71 in 2011 to 0.78 in 2020 (P for trend 0.060). Massive transfusion with lower FFP-to-RBC (< 0.75) and platelets-to-RBC ratio (< 1.00) were associated with increased in-hospital mortality compared with those ≥ 1.00, while there were linear increases in adverse events with increasing FFP and platelets ratios.

CONCLUSIONS

This study demonstrated a declining trend in the incidence and a rise in higher FFP-to-RBC ratios in massive transfusion in association with patient outcomes for trauma from 2011 to 2020 in Japan.

Guided blood transfusion of trauma patients with rotational thromboelastometry: a single-center cohort study

BACKGROUND

Rotational thromboelastometry (ROTEM) is a blood test used to measure in vitro clot strength as a surrogate for a patient's ability to form clots in vivo. This provides information about induction, formation, and clot lysis, allowing goal-directed transfusion therapy for specific hemostatic needs. We sought to evaluate the effect of ROTEM-guided transfusion on blood product usage and in-hospital mortality among patients with a traumatic injury.

METHODS

This was a single-center observational cohort analysis of emergency department patients in a Level 1 trauma center. We compared blood usage in trauma patients in whom ratio-based massive hemorrhage protocols were activated in the twelve months before the introduction of ROTEM (pre-ROTEM group) to the twelve months following the introduction of ROTEM (ROTEM-period group). ROTEM was implemented in this center in November 2016. The ROTEM device allowed clinicians to make real-time decisions about blood product therapy in resuscitation for trauma.

RESULTS

The pre-ROTEM group contained 21 patients. Forty-three patients were included from the ROTEM-period, of whom 35 patients received ROTEM-guided resuscitation (81% compliance). The use of fibrinogen concentrate was significantly higher in the ROTEM-period group (pre-ROTEM mean 0.2 vs. ROTEM-period mean 0.8; p = 0.006). There was no significant difference in the number of units of red blood cells, platelets, cryoprecipitate, or fresh frozen plasma transfused between these groups. There was no significant difference in the mortality rate between the pre-ROTEM and ROTEM-period groups (33% vs. 19%; p = 0.22).

CONCLUSIONS

The introduction of ROTEM-guided transfusion at this institution was associated with increased fibrinogen usage, but this did not impact mortality rates. There was no difference in the administration of red blood cell, fresh frozen plasma, platelet, and cryoprecipitate. Future research should focus on increased ROTEM compliance and optimizing ROTEM-guided transfusion to prevent blood product overuse among trauma patients.

Anticoagulation practices and complications associated with Impella® support at an advanced cardiac center in the Middle East gulf region

Anticoagulation during Impella® support is a challenge due to its complications and inconsistent practice across the globe. This observational, retrospective chart review included all patients with Impella® support at our advanced cardiac center at a quaternary care hospital in the Middle East gulf region. The study was conducted over six years (2016-2022), a time period during which manufacturer recommendations for purge solution, anticoagulation protocols as well as Impella® place in therapy and utilization were all evolving. We aimed to evaluate the efficacy of different anticoagulation practices and association with complications and outcomes. Forty-one patients underwent Impella® during the study period, including 25 patients with support for more than 12 h, and are the focus of our analysis. Cardiogenic shock (n = 25, 60.9%) was the primary indication for Impella®, followed by facilitating high-risk PCI (n = 15, 36.7%) and left ventricular afterload reduction in patients undergoing veno-arterial extracorporeal membrane oxygenation (n = 1, 2.4%). Our overall Impella® usage evolved over the years from a primary use to facilitate a high-risk PCI to the recent more common use of LV unloading in cardiogenic shock. No patients experienced device malfunction and the incidence of other complications including ischemic stroke and bleeding were comparable to those reported in the literature (12.2% and 24% respectively). The 30-day all-cause mortality of 41 patients was 53.6%. In line with the evolving recommendations and evidence, we observed an underutilization of non-heparin-based purge solutions and inconsistent management of anticoagulation in the setting of both Impella® and VA ECMO which necessitates more education and protocols.

Surgical Science and the Evolution of Critical Care Medicine

Surgical science has driven innovation and inquiry across adult and pediatric disciplines that provide critical care regardless of location. Surgically originated but broadly applicable knowledge has been globally shared within the pages Critical Care Medicine over the last 50 years.

How to Clear Polytrauma Patients for Fracture Fixation: Results of a systematic review of the literature

INTRODUCTION

Early patient assessment is relevant for surgical decision making in severely injured patients and early definitive surgery is known to be beneficial in stable patients. The aim of this systematic review is to extract parameters indicative of risk factors for adverse outcome. Moreover, we aim to improve decision making and separate patients who would benefit from early versus staged definitive surgical fixation.

METHODS

Following the PRISMA guidelines, a systematic review of peer-reviewed articles in English or German language published between (2000 and 2022) was performed. The primary outcome was the pathophysiological response to polytrauma including coagulopathy, shock/haemorrhage, hypothermia and soft tissue injury (trauma, brain injury, thoracic and abdominal trauma, and musculoskeletal injury) to determine the treatment strategy associated with the least amount of complications. Articles that had used quantitative parameters to distinguish between stable and unstable patients were summarized. Two authors screened articles and discrepancies were resolved by consensus. Quantitative values for relevant parameters indicative of an unstable polytrauma patient were obtained.

RESULTS

The initial systematic search using MeSH criteria yielded 1550 publications deemed relevant to the following topics (coagulopathy (n = 37), haemorrhage/shock (n = 7), hypothermia (n = 11), soft tissue injury (n = 24)). Thresholds for stable, borderline, unstable and in extremis conditions were defined according to the existing literature as follows: Coagulopathy; International Normalized Ratio (INR) and viscoelastic methods (VEM)/Blood/shock; lactate, systolic blood pressure and haemoglobin, hypothermia; thresholds in degrees Celsius/Soft tissue trauma: traumatic brain injury, thoracic and abdominal trauma and musculoskeletal trauma.

CONCLUSION

In this systematic literature review, we summarize publications by focusing on different pathways that stimulate pathophysiological cascades and remote organ damage. We propose that these parameters can be used for clinical decision making within the concept of safe definitive surgery (SDS) in the treatment of severely injured patients.

Coagulation measures after cardiac arrest (CMACA)

BACKGROUND

During cardiac arrest (CA) and after cardiopulmonary resuscitation, activation of blood coagulation and inadequate endogenous fibrinolysis occur. The aim of this study was to describe the time course of coagulation abnormalities after out-of-hospital CA (OHCA) and to examine the association with clinical outcomes in patients undergoing targeted temperature management (TTM) after OHCA.

METHODS

This prospective, multicenter, observational cohort study was performed in eight emergency departments in Korea between September 2018 and September 2019. Laboratory findings from hospital admission and 24 hours after return of spontaneous circulation (ROSC) were analyzed. The primary outcome was cerebral performance category (CPC) at discharge, and the secondary outcome was in-hospital mortality.

RESULTS

A total of 170 patients were included in this study. The lactic acid, prothrombin time (PT), activated partial thrombin time (aPTT), international normalized ratio (INR), and D-dimer levels were higher in patients with poor neurological outcomes at admission and 24 h after ROSC. The lactic acid and D-dimer levels decreased over time, while fibrinogen increased over time. PT, aPTT, and INR did not change over time. The PT at admission and D-dimer levels 24 h after ROSC were associated with neurological outcomes at hospital discharge. Coagulation-related factors were moderately correlated with the duration of time from collapse to ROSC.

CONCLUSION

The time-dependent changes in coagulation-related factors are diverse. Among coagulation-related factors, PT at admission and D-dimer levels 24 h after ROSC were associated with poor neurological outcomes at hospital discharge in patients treated with TTM.

Early Hypocalcemia in Severe Trauma: An Independent Risk Factor for Coagulopathy and Massive Transfusion

The rapid identification of patients at risk for massive blood transfusion is of paramount importance as uncontrolled exsanguination may lead to death within 2 to 6 h. The aim of this study was to analyze a cohort of severe trauma patients to identify risk factors associated with massive transfusion requirements and hypocalcemia. All major trauma (ISS > 16) presented directly from the scene to the Niguarda hospital between 1 January 2015 and 31 December 2021 were analyzed. A total of 798 patients were eligible out of 1586 screened. Demographic data showed no significant difference between hypocalcemic (HC) and normocalcemic (NC) patients except for the presence of crush trauma, alcohol intake (27% vs. 15%, p < 0.01), and injury severity score (odds ratio 1.03, p = 0.03). ISS was higher in the HC group and was an independent, even if weak, predictor of hypocalcemia (odds ratio 1.03, p = 0.03). Prehospital data showed a lower mean systolic arterial pressure (SAP) and a higher heart rate (HR) in the HC group (105 vs. 127, p < 0.01; 100 vs. 92, p < 0.001, respectively), resulting in a higher shock index (SI) (1.1 vs. 0.8, p < 0.001). Only retrospective studies such as ours are available, and while hypocalcemia seems to be an independent predictor of mortality and massive transfusion, there is not enough evidence to support causation. Therefore, randomized prospective studies are suggested.

Safety of Contemporary Carotid Artery Stenting and Associated Risk Factors for Treatment of Carotid Artery Stenosis

BACKGROUND

The prevalence of carotid artery atherosclerosis and stroke is increasing. Carotid artery stenting (CAS), which treats carotid artery stenosis and prevents strokes, has benefited from advances in techniques and technology. In this study, we aimed to identify significant risk factors for major complications following contemporary CAS.

METHODS

Utilizing the National Surgical Quality Improvement Program registry, we investigated individuals who underwent CAS between the years 2015-2018. Multivariable logistic regression was performed to identify risk factors associated with stroke, myocardial infarction (MI), and death within 30 days of CAS.

RESULTS

Of the 770 patients within the National Surgical Quality Improvement Program registry who met study criteria, 3.2% experienced strokes, 1.6% experienced MIs, and 2.2% died within 30 days of CAS. A total of 6.1% of patients experienced any of these major complications. Of the 395 asymptomatic patients, 3.5% suffered a stroke, 1.5% experienced an MI, and 1.0% died for a total of 5.6% patients suffering from any event. Of the 375 symptomatic patients, there were 2.9% strokes, 1.6% MIs, and 3.5% deaths with 6.7% suffering any event. Age, race, and hyponatremia were significantly associated with stroke, and hyponatremia was associated with MI. Age, anemia, hypoalbuminemia, international normalized ratio, and emergency case were associated with death.

CONCLUSIONS

These results suggest that preoperative risk stratification of CAS patients may not be straightforward as each adverse event has its own risk factors, precluding a generalized CAS risk stratification scoring system from being created. This paper can aid in patient selection for CAS by highlighting risk factors in modern CAS.

Factor V Leiden: Development of VTE in Surgery and Trauma Patients: A Systematic Review

BACKGROUND

Factor V Leiden (FVL) is a hereditary thrombophilia, which causes the blood to be more hypercoagulable; in essence, the blood tends to clot more easily, especially under certain circumstances. It is the most common genetic mutation, causing thrombophilia in patients of white background. Patients that have FVL are at a higher risk to develop venous thromboembolism (VTE) after surgery and trauma.

OBJECTIVE

The purpose of this review is to identify FVL as a risk factor, which may impede optimum acute cardiopulmonary management which may contribute to a longer length of stay (LOS) in the hospital.

METHODS

This article is a systematic review of the literature involving research printed in peer-reviewed journals from 2015 to 2018. The University of Tennessee Health Science Center online library, PubMed, and Google Scholar were used for the literature search.

RESULTS

The results of this study determined that although FVL is in fact a risk factor, which may impede optimum acute cardiopulmonary management which may contribute to a longer LOS, management of VTE is no different for a person with FVL compared with those without FVL.

CONCLUSION

Factor V Leiden is a risk factor for the development of VTE, specifically deep vein thrombosis, in surgical, trauma, pregnant, and hormone replacement therapy patients, thus increasing LOS and recurrence of such events. Regardless of FVL status, management of VTE should be initiated promptly and discontinued when appropriate.

Persistent coagulopathy after gunshot traumatic brain injury: the importance of INR and the SPIN score

INTRODUCTION

Penetrating ballistic brain injury (gunshot traumatic brain injury or GTBI) is associated with a high mortality. Admission Glascow Coma Scale (GCS), injury severity score and neurological findings, cardiopulmonary instability, coagulopathy and radiological finding such as bullet trajectory and mass effect are shown to predict survival after GTBI. We aimed to examine the dynamics of the observed coagulopathy and its association with outcome.

METHODS

In this single-centered retrospective cohort study, we examined 88 patients with GTBI between 2015 and 2021. Variables analyzed include patient age; temperature, hemodynamic and respiratory variables, admission Glasgow Coma Scale (GCS); injury severity score (ISS); head abbreviated injury scale (AIS); Marshall, Rotterdam, SPIN and Baylor scores, and laboratory data including PTT, INR and platelet count. Receiver operating characteristic analysis was conducted to evaluate the performance of the predictive models.

RESULTS

The average age of our sample was 28.5 years and a majority were male subjects (92%). Fifty-four (62%) of the patients survived to discharge. The GCS score, as well as the motor, verbal, and eye-opening sub-scores were higher in survivors (P < 0.001). As was expected, radiologic findings including the Marshall and Rotterdam Scores were also associated with survival (P < 0.001). Although the ISS and Head AIS scores were higher (P < 0.001), extracranial injuries were not more prevalent in non-survivors (P= 0.567). Non-survivors had lower platelet counts and elevated PTT and INR (P < 0.001) on admission. PTT normalized within 24 h but INR continued to increase in non-survivors. SPIN score, which includes INR, was a better predictor for mortality than Rotterdam, Marshall, and Baylor etc. CONCLUSION: Progressively increasing INR after GTBI is associated with poor outcome and may indicate consumption coagulopathy from activation of the extrinsic pathway of coagulation and metabolic derangements that are triggered and sustained by the brain injury. The SPIN score, which incorporates INR as a major survival score component, outperforms other available prediction models for predicting outcome after GTBI.

Proteomics of Coagulopathy Following Injury Reveals Limitations of Using Laboratory Assessment to Define Trauma-Induced Coagulopathy to Predict Massive Transfusion

Objective

Trauma-induced coagulopathy (TIC) is provoked by multiple mechanisms and is perceived to be one driver of massive transfusions (MT). Single laboratory values using prothrombin time (INR) or thrombelastography (TEG) are used to clinically define this complex process. We used a proteomics approach to test whether current definitions of TIC (INR, TEG, or clinical judgement) are sufficient to capture the majority of protein changes associated with MT.

Methods

Eight level-I trauma centers contributed blood samples from patients available early after injury. TIC was defined as INR >1.5 (INR-TIC), TEG maximum amplitude <50mm (TEG-TIC), or clinical judgement (Clin-TIC) by the trauma surgeon. MT was defined as > 10 units of red blood cells in 24 hours or > 4 units RBC/hour during the first 4 hr. SomaLogic proteomic analysis of 1,305 proteins was performed. Pathways associated with proteins dysregulated in patients with each TIC definition and MT were identified.

Results

Patients (n=211) had a mean injury severity score of 24, with a MT and mortality rate of 22% and 12%, respectively. We identified 578 SOMAscan analytes dysregulated among MT patients, of which INR-TIC, TEG-TIC, and Clin-TIC patients showed dysregulation only in 25%, 3%, and 4% of these, respectively. TIC definitions jointly failed to show changes in 73% of the protein levels associated with MT, and failed to identify 26% of patients that received a massive transfusion. INR-TIC and TEG-TIC patients showed dysregulation of proteins significantly associated with complement activity. Proteins dysregulated in Clin-TIC or massive transfusion patients were not significantly associated with any pathway.

Conclusion

These data indicate there are unexplored opportunities to identify patients at risk for massive bleeding. Only a small subset of proteins that are dysregulated in patients receiving MT are statistically significantly dysregulated among patients whose TIC is defined based solely on laboratory measurements or clinical assessment.

Extended Coagulation Profiling in Isolated Traumatic Brain Injury: A CENTER-TBI Analysis

BACKGROUND

Trauma-induced coagulopathy in traumatic brain injury (TBI) remains associated with high rates of complications, unfavorable outcomes, and mortality. The underlying mechanisms are largely unknown. Embedded in the prospective multinational Collaborative European Neurotrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study, coagulation profiles beyond standard conventional coagulation assays were assessed in patients with isolated TBI within the very early hours of injury.

METHODS

Results from blood samples (citrate/EDTA) obtained on hospital admission were matched with clinical and routine laboratory data of patients with TBI captured in the CENTER-TBI central database. To minimize confounding factors, patients with strictly isolated TBI (iTBI) (n = 88) were selected and stratified for coagulopathy by routine international normalized ratio (INR): (1) INR < 1.2 and (2) INR ≥ 1.2. An INR > 1.2 has been well adopted over time as a threshold to define trauma-related coagulopathy in general trauma populations. The following parameters were evaluated: quick's value, activated partial thromboplastin time, fibrinogen, thrombin time, antithrombin, coagulation factor activity of factors V, VIII, IX, and XIII, protein C and S, plasminogen, D-dimer, fibrinolysis-regulating parameters (thrombin activatable fibrinolysis inhibitor, plasminogen activator inhibitor 1, antiplasmin), thrombin generation, and fibrin monomers.

RESULTS

Patients with iTBI with INR ≥ 1.2 (n = 16) had a high incidence of progressive intracranial hemorrhage associated with increased mortality and unfavorable outcome compared with patients with INR < 1.2 (n = 72). Activity of coagulation factors V, VIII, IX, and XIII dropped on average by 15-20% between the groups whereas protein C and S levels dropped by 20%. With an elevated INR, thrombin generation decreased, as reflected by lower peak height and endogenous thrombin potential (ETP), whereas the amount of fibrin monomers increased. Plasminogen activity significantly decreased from 89% in patients with INR < 1.2 to 76% in patients with INR ≥ 1.2. Moreover, D-dimer levels significantly increased from a mean of 943 mg/L in patients with INR < 1.2 to 1,301 mg/L in patients with INR ≥ 1.2.

CONCLUSIONS

This more in-depth analysis beyond routine conventional coagulation assays suggests a counterbalanced regulation of coagulation and fibrinolysis in patients with iTBI with hemostatic abnormalities. We observed distinct patterns involving key pathways of the highly complex and dynamic coagulation system that offer windows of opportunity for further research. Whether the changes observed on factor levels may be relevant and explain the worse outcome or the more severe brain injuries by themselves remains speculative.

Is it possible to improve prediction of outcome and blood requirements in the severely injured patients by defining categories of coagulopathy?

PURPOSE

It has been suggested to define the Trauma-induced coagulopathy (TIC) with a PT_ratio threshold of 1.20. We hypothesized that a more pragmatic classification would grade severity according to the PT_ratio (or corresponding ROTEM clotting time: EXTEM-CT), and that this would correlate better with the need for blood products (BP) and prognosis.

METHODS

Retrospective analysis of prospectively collected data of 1076 severely injured patients admitted from 01/2011 to 12/2019 in a university hospital. To determine the number of TIC categories and the best PT_ratio or EXTEM-CT thresholds for mortality at 24-h, a modified Mazumdar approach was used. Multivariate regression analyses were done to describe the relationship between PT_ratio and ROTEM parameter subclasses with mortality.

RESULTS

Three thresholds were, respectively, identified for PT_ratio (1.20, 1.90 and 3.00) and EXTEM-CT (90 s, 130 s, 200 s). The following categories were defined for PT_ratio: ≤ 1.20 (No TIC), 1.21-1.90 (Moderate TIC), 1.91-3.00 (severe TIC), > 3.00 (major TIC); and for EXTEM-CT: < 91 s (no TIC), 91-130 s (moderate TIC), 131-200 s (severe TIC) and > 200 s (major TIC). We observed that when the PT_ratio (or EXTEM-CT) increased, mortality and BP requirements increased. After multiple adjustments, we observed that each subclass of PT_ratio and EXTEM-CT was independently associated with mortality at 24-h.

CONCLUSION

In this study, we have described a pragmatic classification of coagulopathy utilizing PT_ratio and EXTEM-CT where increasing severity was associated with prognosis and the amount of BP administered. This could allow clinicians to better predict the outcome and anticipate the need for blood products.

Massive transfusion practices in Tunisia and protocol proposal

INTRODUCTION

Massive transfusion (MT) is a life-saving therapy in situations of major hemorrhage awaiting radical haemostatic treatment. Poor management and control of this therapy may, however, compromise the patient's vital prognosis. The main aim of our study was to take stock of massive transfusion practices in Tunisia. The secondary aim was to propose a massive transfusion protocol.

METHODS

An analytical observational study based on a questionnaire was conducted. We targeted physicians brought in their clinical practice to use MT.

RESULTS

A total of 124 clinicians responded to the questionnaire. The majority (62%) were anesthesiologists or emergency physicians. More than half of the participants were residents (51%). The use of MT based on a clinical or biological score was only found for a minority (13%). The initial order was for the majority of participants (N=69) made up of red blood cell concentrates (RBC) and fresh frozen plasma (FFP). The FFP: RBC ratio was1:2 for 51% of the participants. A higher ratio was adopted by the rest. Respectively 23.5% and 9.6% of participants transfused platelets and fibrinogen concentrates without waiting for the result of biology. The use of tranexamic acid was systematically advocated by 60.5% of clinicians. The majority (86.3%) adopted a restrictive transfusion strategy (target hemoglobin between 7 and 9 g/dl). The latter was more adopted by the youngest physicians (92.1% of residents versus 55.6% of professors; p=0.008).

CONCLUSIONS

The professional practices of MT in Tunisia are heterogeneous. Given the lack of a clear institutionalized procedure which frames this therapy, a MT protocol has thus been proposed.

Prognostic significance of international normalised ratio and prothrombin time in Chinese acute ischaemic stroke patients

BACKGROUND

We investigated the association between international normalised ratio (INR) and prothrombin time (PT) levels on hospital admission and in-hospital outcomes in acute ischaemic stroke (AIS) patients.

METHODS

A total of 3175 AIS patients enrolled from December 2013 to May 2014 across 22 hospitals in Suzhou city were included. We divided patients into four groups according to their level of admission INR: (<0.92), Q2 (0.92-0.98), Q3 (0.98-1.04) and Q4 (≥1.04) and PT. Logistic regression models were used to estimate the effect of INR and PT on death or major disability (modified Rankin Scale score (mRS)>3), death and major disability (mRS scores 4-5) separately on discharge in AIS patients.

RESULTS

Having an INR level in the highest quartile (Q4) was associated with an increased risk of death or major disability (OR 1.69; 95% CI 1.23 to 2.31; P-trend=0.001), death (OR, 2.64; 95% CI 1.12 to 6.19; P-trend=0.002) and major disability on discharge (OR, 1.56; 95% CI 1.13 to 2.15; P-trend=0.008) in comparison to Q1 after adjusting for potential covariates. Moreover, in multivariable logistic regression models, having a PT level in the highest quartile also significantly increased the risk of death (OR, 2.38; 95% CI 1.06 to 5.32; P-trend=0.006) but not death or major disability (P-trend=0.240), major disability (P-trend=0.606) on discharge.

CONCLUSIONS

High INR at admission was independently associated with death or major disability, death and major disability at hospital discharge in AIS patients and increased PT was also associated with death at hospital discharge.

Diagnostic and Prognostic Significance of the Prothrombin Time/International Normalized Ratio in Sepsis and Septic Shock

OBJECTIVE

The study investigates the diagnostic and prognostic significance of the prothrombin time/international normalized ratio (PT/INR) in patients with sepsis and septic shock.

BACKGROUND

Sepsis may be complicated by disseminated intravascular coagulation (DIC). While the status of coagulopathy of septic patients is represented within the sepsis-3 definition by assessing the platelet count, less data regarding the prognostic impact of the PT/INR in patients admitted with sepsis and septic shock is available.

METHODS

Consecutive patients with sepsis and septic shock from 2019 to 2021 were included. Blood samples were retrieved from day of disease onset (ie, day 0), as well as on day 1, 2, 4, 6 and 9 thereafter. Firstly, the diagnostic value of the PT/INR in comparison to the activated partial thromboplastin time (aPTT) was tested for septic shock compared to sepsis without shock. Secondly, the prognostic value of the PT/INR for 30-day all-cause mortality was tested. Statistical analyses included univariable t-tests, Spearman's correlations, C-statistics, Kaplan-Meier analyses and Cox proportional regression analyses.

RESULTS

338 patients were included (56% sepsis without shock, 44% septic shock). The overall rate of all-cause mortality at 30 days was 52%. With an area under the curve (AUC) of 0.682 (p= .001) on day 0, the PT/INR revealed moderate discrimination of septic shock and sepsis without shock. Furthermore, PT/ INR was able to discriminate non-survivors and survivors at 30 days (AUC = 0.612; p = .001). Patients with a PT/INR >1.5 had higher rates of 30-day all-cause mortality than patients with lower values (mortality rate 73% vs 48%; log rank p = .001; HR = 2.129; 95% CI 1.494-3.033; p = .001), even after multivariable adjustment (HR = 1.793; 95% CI 1.343-2.392; p = .001). Increased risk of 30-day all-cause mortality was observed irrespective of concomitant thrombocytopenia.

CONCLUSION

The PT/INR revealed moderate diagnostic accuracy for septic shock but was associated with reliable prognostic accuracy with regard to 30-day all-cause mortality in patients admitted with sepsis and septic shock.

Hypofibrinogenaemia and hypocalcaemia in adult trauma patients receiving pre-hospital packed red blood cell transfusions: Potential for supplementary pre-hospital therapeutic interventions

OBJECTIVE

To report the arrival ionised calcium (iCa) and fibrinogen concentrations in trauma patients treated with packed red blood cells by the road-based high-acuity response units of a metropolitan ambulance service.

METHODS

A retrospective review of trauma patients treated with packed red blood cells by high-acuity response units between January 2012 and December 2016. Patients were identified from databases at southeast Queensland adult trauma centres, Pathology Queensland Central Transfusion Laboratory, Gold Coast University Hospital blood bank and the Queensland Ambulance Service. Patient characteristics, results of laboratory tests within 30 min of ED arrival were analysed.

RESULTS

A total of 164 cases were analysed. The median injury severity score was 33.5 (interquartile range 22-41), with blunt trauma the commonest mechanism of injury (n = 128, 78.0%). Fifty-eight of the 117 patients (24.4%) with fibrinogen measured had a fibrinogen concentration ≤1.5 g/L; 79 of the 123 patients (64.2%) with an international normalised ratio (INR) measurement had an INR >1.2; 97 of 148 patients (63.8%) with an iCa measured, had an iCa below the Pathology Queensland reference range of 1.15-1.32 mmol/L. Arrival fibrinogen concentration ≤1.5 g/L and arrival iCa ≤1.00 were associated with in-hospital mortality with odds ratio 11.90 (95% confidence interval 4.50-31.65) and odds ratio 4.97 (95% confidence interval 1.42-17.47), respectively.

CONCLUSIONS

Hypocalcaemia and hypofibrinogenaemia on ED arrival were common in this cohort. Future work should evaluate whether outcomes improve by correction of these deficits during the pre-hospital phase of trauma care.

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

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

Simplified treatment algorithm for the management of trauma-induced hemorrhage without viscoelastic testing

Uncontrolled bleeding after major trauma remains a significant cause of death, with up to a third of trauma patients presenting with signs of coagulopathy at hospital admission. Rapid correction of coagulopathy is therefore vital to improve mortality rates and patient outcomes in this population. Early and repeated monitoring of coagulation parameters followed by clear protocols to correct hemostasis is the recommended standard of care for bleeding trauma patients. However, although a number of treatment algorithms are available, these are frequently complex and can rely on the use of viscoelastic testing, which is not available in all treatment centers. We therefore set out to develop a concise and pragmatic algorithm to guide treatment of bleeding trauma patients without the use of point-of-care viscoelastic testing. The algorithm we present here is based on published guidelines and research, includes recommendations regarding treatment and dosing, and is simple and clear enough for even an inexperienced physician to follow. In this way, we have demonstrated that treatment protocols can be developed and adapted to the resources available, to offer clear and relevant guidance to the entire trauma team.

Disseminated intravascular coagulation immediately after trauma predicts a poor prognosis in severely injured patients

Trauma patients die from massive bleeding due to disseminated intravascular coagulation (DIC) with a fibrinolytic phenotype in the early phase, which transforms to DIC with a thrombotic phenotype in the late phase of trauma, contributing to the development of multiple organ dysfunction syndrome (MODS) and a consequently poor outcome. This is a sub-analysis of a multicenter prospective descriptive cross-sectional study on DIC to evaluate the effect of a DIC diagnosis on the survival probability and predictive performance of DIC scores for massive transfusion, MODS, and hospital death in severely injured trauma patients. A DIC diagnosis on admission was associated with a lower survival probability (Log Rank P < 0.001), higher frequency of massive transfusion and MODS and a higher mortality rate than no such diagnosis. The DIC scores at 0 and 3 h significantly predicted massive transfusion, MODS, and hospital death. Markers of thrombin and plasmin generation and fibrinolysis inhibition also showed a good predictive ability for these three items. In conclusion, a DIC diagnosis on admission was associated with a low survival probability. DIC scores obtained immediately after trauma predicted a poor prognosis of severely injured trauma patients.

Trauma-induced coagulopathy

Uncontrolled haemorrhage is a major preventable cause of death in patients with traumatic injury. Trauma-induced coagulopathy (TIC) describes abnormal coagulation processes that are attributable to trauma. In the early hours of TIC development, hypocoagulability is typically present, resulting in bleeding, whereas later TIC is characterized by a hypercoagulable state associated with venous thromboembolism and multiple organ failure. Several pathophysiological mechanisms underlie TIC; tissue injury and shock synergistically provoke endothelial, immune system, platelet and clotting activation, which are accentuated by the 'lethal triad' (coagulopathy, hypothermia and acidosis). Traumatic brain injury also has a distinct role in TIC. Haemostatic abnormalities include fibrinogen depletion, inadequate thrombin generation, impaired platelet function and dysregulated fibrinolysis. Laboratory diagnosis is based on coagulation abnormalities detected by conventional or viscoelastic haemostatic assays; however, it does not always match the clinical condition. Management priorities are stopping blood loss and reversing shock by restoring circulating blood volume, to prevent or reduce the risk of worsening TIC. Various blood products can be used in resuscitation; however, there is no international agreement on the optimal composition of transfusion components. Tranexamic acid is used in pre-hospital settings selectively in the USA and more widely in Europe and other locations. Survivors of TIC experience high rates of morbidity, which affects short-term and long-term quality of life and functional outcome.

Protocol for a multicentre prehospital randomised controlled trial investigating tranexamic acid in severe trauma: the PATCH-Trauma trial

INTRODUCTION

Haemorrhage causes most preventable prehospital trauma deaths and about a third of in-hospital trauma deaths. Tranexamic acid (TXA), administered soon after hospital arrival in certain trauma systems, is an effective therapy in preventing or managing acute traumatic coagulopathy. However, delayed administration of TXA appears to be ineffective or harmful. The effectiveness of prehospital TXA, incidence of thrombotic complications, benefit versus risk in advanced trauma systems and the mechanism of benefit remain uncertain.

METHODS AND ANALYSIS

The Pre-hospital Anti-fibrinolytics for Traumatic Coagulopathy and Haemorrhage (The PATCH-Trauma study) is comparing TXA, initiated prehospital and continued in hospital over 8 hours, with placebo in patients with severe trauma at risk of acute traumatic coagulopathy. We present the trial protocol and an overview of the statistical analysis plan. There will be 1316 patients recruited by prehospital clinicians in Australia, New Zealand and Germany. The primary outcome will be the eight-level Glasgow Outcome Scale Extended (GOSE) at 6 months after injury, dichotomised to favourable (GOSE 5-8) and unfavourable (GOSE 1-4) outcomes, analysed using an intention-to-treat (ITT) approach. Secondary outcomes will include mortality at hospital discharge and at 6 months, blood product usage, quality of life and the incidence of predefined adverse events.

ETHICS AND DISSEMINATION

The study was approved by The Alfred Hospital Research and Ethics Committee in Victoria and also approved in New South Wales, Queensland, South Australia, Tasmania and the Northern Territory. In New Zealand, Northern A Health and Disability Ethics Committee provided approval. In Germany, Witten/Herdecke University has provided ethics approval. The PATCH-Trauma study aims to provide definitive evidence of the effectiveness of prehospital TXA, when used in conjunction with current advanced trauma care, in improving outcomes after severe injury.

TRIAL REGISTRATION NUMBER

NCT02187120.

The swine as a vehicle for research in trauma-induced coagulopathy: Introducing principal component analysis for viscoelastic coagulation tests

BACKGROUND

Uncontrolled bleeding is the leading cause of potentially preventable deaths among trauma patients. Tissue injury and shock result in trauma-induced coagulopathy (TIC). There are still uncertainties regarding detection methods and best practice management for TIC, and a deeper understanding of the pathophysiology requires robust animal models. The applicability of swine in coagulation studies, particularly after trauma has not been sufficiently elucidated. We, therefore, evaluated the swine as a vehicle for TIC research in a selection of trauma modalities.

METHODS

Twenty-six landrace swine (3 females/23 males) (mean weight, 60.0 kg) were anesthetized and randomized to negative controls, receiving no manipulation (n = 5), positive controls by hemodilution (n = 5), pulmonary contusion without hemorrhage (n = 5), pulmonary contusion with hemorrhage (n = 5), and blast polytrauma with hypothermia, hypoperfusion, hypoventilation, and systemic inflammation (n = 6). A comprehensive coagulation panel was analyzed at baseline, 20 minutes and 120 minutes after trauma.

RESULTS

PT(INR), aPTT, thrombocytes, and fibrinogen did not change after trauma. D-dimer increased (p < 0.0001), prothrombin decreased (p < 0.05) and aPC decreased (p < 0.01) after polytrauma. PAI-1 decreased after pulmonary contusion with hemorrhage (p < 0.05). Positive controls displayed changes in PT(INR), thrombocytes, fibrinogen, prothrombin, aPC (p < 0.05). Principal Component Analysis of rotational thromboelastometry presented pathologic coagulation profiles in both polytrauma and positive control groups with vectors extending outside the 95% confidence interval, which were not detected in negative controls.

CONCLUSION

Coagulopathy was induced after severe porcine blast polytrauma, specifically detected in rotational thromboelastometry. A novel method for principal component analysis of viscoelastic tests was introduced which may increase the detection sensitivity and differentiation of TIC phenotypes and should be further investigated in trauma populations.

Retrospective high volume comparative study suggests that patients on aspirin could have immediate surgery for hip fractures without significant blood loss

PURPOSE

This study aimed to investigate the effects of aspirin on peri-operative hidden blood loss during hip fracture surgery by adjusting for possible factors affecting blood loss using a propensity score matching method.

METHODS

We retrospectively collected data from a cohort of isolated hip fracture patients (aged ≥ 65 years)who underwent surgery from January 2010 to December 2019. The study's primary outcome was blood loss from admission to the day after surgery in the aspirin and control groups. We estimated the hidden blood loss, calculated based on patient's blood volume, haemoglobin measurements, and blood transfusions. The secondary outcome focused on the requirement for blood transfusion. We adjusted for possible factors affecting blood loss using a propensity score matching method and statistically examined the effects of aspirin on hip fracture surgery.

RESULTS

We enrolled 806 patients of whom 271 (34%) were taking anticoagulant and antiplatelet drugs, while 114 (14%) were taking only aspirin (aspirin group). A total of 535 patients were not taking antiplatelets and anticoagulants (control group). In propensity score matching, 103 patients were matched. Aspirin was not associated with a significantly higher risk of hidden blood loss (aspirin group; median 598 mL [410-783 mL] vs control group; median 556 ml [321-741 mL], p = 0.14) and higher risk of blood transfusion requirement (aspirin group; 49 patients [48%] vs control group; 39 patients [38%], p = 0.21).

CONCLUSION

Aspirin did not affect peri-operative blood loss in hip fracture surgery. We concluded that patients taking aspirin can safely undergo hip fracture surgery without delay.

Variations and obstacles in the use of coagulation factor concentrates for major trauma bleeding across Europe: outcomes from a European expert meeting

Purpose

Trauma is a leading cause of mortality, with major bleeding and trauma-induced coagulopathy (TIC) contributing to negative patient outcomes. Treatments for TIC include tranexamic acid (TXA), fresh frozen plasma (FFP), and coagulation factor concentrates (CFCs, e.g. prothrombin complex concentrates [PCCs] and fibrinogen concentrate [FCH]). Guidelines for TIC management vary across Europe and a clear definition of TIC is still lacking.

Methods

An advisory board involving European trauma experts was held on 02 February 2019, to discuss clinical experience in the management of trauma-related bleeding and recommendations from European guidelines, focusing on CFC use (mainly FCH). This review summarises the discussions, including TIC definitions, gaps in the guidelines that affect their implementation, and barriers to use of CFCs, with suggested solutions.

Results

A definition of TIC, which incorporates clinical (e.g. severe bleeding) and laboratory parameters (e.g. low fibrinogen) is suggested. TIC should be treated immediately with TXA and FCH/red blood cells; subsequently, if fibrinogen ≤ 1.5 g/L (or equivalent by viscoelastic testing), treatment with FCH, then PCC (if bleeding continues) is suggested. Fibrinogen concentrate, and not FFP, should be administered as first-line therapy for TIC. Several initiatives may improve TIC management, with improved medical education of major importance; generation of new and stronger data, simplified clinical practice guidance, and improved access to viscoelastic testing are also critical factors.

Conclusions

Management of TIC is challenging. A standard definition of TIC, together with initiatives to facilitate effective CFC administration, may contribute to improved patient care and outcomes.

Is the use of greater than 1 L of intravenous crystalloids associated with worse outcomes in trauma patients?

OBJECTIVE

Advanced Trauma Life Support guidelines recommend only 1 L of intravenous (IV) crystalloid before transitioning to blood products. We sought to determine if receiving >1 L of IV crystalloid during the initial resuscitation is associated with worse outcomes. We also sought to determine if receiving no crystalloids is associated with better outcomes.

METHODS

We performed a single center retrospective study using trauma registry data, which was supplemented by manual chart review. We only included patients who had an initial heart rate ≥ 100 beats/min or a systolic blood pressure ≤ 90 mmHg. For each patient, we determined the total amount of IV crystalloid administered in the first 3 h after arrival to the hospital plus prehospital crystalloid. We performed multivariate regression analyses to determine if there is an association between the administration of >1 L of crystalloids or no crystalloids with in-hospital mortality, hospital length of stay (LOS), or packed red blood cells (PRBCs) transfused.

RESULTS

Between January 1, 2018 and September 30, 2019, there were 878 who met criteria for enrollment. Among those, 55.0% received ≤1 L of IV crystalloids, and 45.0% received >1 L. Multivariate analyses showed no significant association between receiving >1 L and mortality (p = 0.61) or PRBCs transfused (p = 0.29), but patients who received >1 L had longer hospital LOS (p = 0.04). We found no association between receiving no crystalloids and mortality, PRBCs transfused, or LOS.

CONCLUSION

On a multivariate analysis of trauma patients, we did not find an association between the administration of >1 L of IV crystalloid and in-hospital mortality or the volume of PRBCs transfused. However, receiving >1 L of crystalloids was associated with a longer hospital LOS. We found no benefit to completely withholding crystalloids.

Prothrombin Time ratio can predict mortality in severe pediatric trauma: Study in a French trauma center level 1

BACKGROUND

Injury results in more deaths in children than all other causes combined, but there is little data regarding the association of early coagulopathy on outcomes in pediatric patients with traumatic injuries. The aim of this study was to determine the optimal cut-off value for the Prothrombin Time ratio (PTr) and to show the diagnostic characteristics of the PTr to predict mortality.

METHODS

We retrospectively included during 4 years all patients less than 16 years old referred to our trauma center for traumatic injury with ISS ≥9.

RESULTS

A total of 272 children were included. Mean age was 9.4 ± 4.8 years and median ISS was 17 [interquartile range, 12 to 26]. Day 28 mortality was 6.7%. The optimal cut-off value in our population for predicting day 28 mortality was 1.24. Using this value, the sensitivity of PTr was 84%, specificity was 82%, positive likelihood ratio was 4.7, and negative likelihood ratio was 0.19. Early mortality (i.e., mortality at 24 h) was also well-predicted (1.0% versus 16.4%, p < .0001), as the need for massive transfuion. Similarly, patients with PTr ≥1.24 at admission presented with a higher rate of severe thoracic and abdominal trauma, higher ISS, higher likelihood of admission to an intensive care unit, longer hospitalization, and higher rate of significant procedure (e.g., surgery or embolization).

CONCLUSIONS

Trauma-induced coagulopathy defined only by a PTr ≥1.24 could be used as a severity predictive marker and as a sensitive, specific, quick, and easy to use tool for admission triage of pediatric patients.

Early thromboelastography in acute traumatic coagulopathy: an observational study focusing on pre-hospital trauma care

Background

Major brain injury and uncontrolled blood loss remain the primary causes of early trauma-related mortality. One-quarter to one-third of trauma patients exhibit trauma-induced coagulopathy (TIC). Thromboelastometry (ROTEM) and thrombelastography (TEG) are valuable alternatives to standard coagulation testing, providing a more comprehensive overview of the coagulation process.

Purpose

Evaluating thromboelastographic profile, the incidence of fibrinolysis (defined as Ly30 > 3%) in severe trauma patients, and factors influencing pathological coagulation pattern.

Methods

Prospective observational 2 years cohort study on severe trauma patients assisted by Helicopter Emergency Medical System (HEMS) and Level 1 Trauma Center, in a tertiary referral University Hospital.

Results

Eighty three patients were enrolled, mean NISS (new injury severity score) 36 (± 13). Mean R value decreased from 7.25 (± 2.6) to 6.19 (± 2.5) min (p < 0.03); 48 (60%) patients had a reduction in R from T₀ to T₁. In NISS 25–40 and NISS > 40 groups, changes in R value increased their significance (p = 0.04 and p < 0.03, respectively). Pathological TEG was found in 71 (88.8%) patients at T₀ and 74 (92.5%) at T₁. Hypercoagulation was present in 57 (71.3%) patients at T_0, and in 66(82.5%) at T₁. 9 (11.3%) patients had hyperfibrinolysis at T₀, 7 (8.8%) patients at T₁. Prevalence of StO₂ < 75% at T₀ was greater in patients whose TEG worsened (7 patients, 46.7%) against whose TEG remained stable or improved (8 patients, 17.4%) from T₀ to T₁ (p = 0.02). 48 (57.8%) patients received < 1000 mL of fluids, while 35 (42.2%) received ≥ 1000 mL. The first group had fewer patients with hypercoagulation (20, 41.6%) than the second (6, 17.6%) at T₁ (p < 0.03). No differences were found for same TEG pattern at T₀, nor other TEG pattern.

Conclusion

Our population is representative of a non-hemorrhagic severe injury subgroup. Almost all of our trauma population had coagulation abnormalities immediately after the trauma; pro-coagulant changes were the most represented regardless of the severity of injury. NISS appears to affect only R parameter on TEG. Hyperfibrinolysis has been found in a low percentage of patients. Hypoperfusion parameters do not help to identify patients with ongoing coagulation impairment. Small volume resuscitation and mild hypotermia does not affect coagulation, at least in the early post-traumatic phase.

Electronic supplementary material

The online version of this article (10.1007/s00068-020-01493-z) contains supplementary material, which is available to authorized users.

A Machine Learning-Based Model to Predict Acute Traumatic Coagulopathy in Trauma Patients Upon Emergency Hospitalization

Acute traumatic coagulopathy (ATC) is an extremely common but silent murderer; this condition presents early after trauma and impacts approximately 30% of severely injured patients who are admitted to emergency departments (EDs). Given that conventional coagulation indicators usually require more than 1 hour after admission to yield results—a limitation that frequently prevents the ability for clinicians to make appropriate interventions during the optimal therapeutic window—it is clearly of vital importance to develop prediction models that can rapidly identify ATC; such models would also facilitate ancillary resource management and clinical decision support. Using the critical care Emergency Rescue Database and further collected data in ED, a total of 1385 patients were analyzed and cases with initial international normalized ratio (INR) values >1.5 upon admission to the ED met the defined diagnostic criteria for ATC; nontraumatic conditions with potentially disordered coagulation systems were excluded. A total of 818 individuals were collected from Emergency Rescue Database as derivation cohorts, then were split 7:3 into training and test data sets. A Pearson correlation matrix was used to initially identify likely key clinical features associated with ATC, and analysis of data distributions was undertaken prior to the selection of suitable modeling tools. Both machine learning (random forest) and traditional logistic regression were deployed for prediction modeling of ATC. After the model was built, another 587 patients were further collected in ED as validation cohorts. The ATC prediction models incorporated red blood cell count, Shock Index, base excess, lactate, diastolic blood pressure, and potential of hydrogen. Of 818 trauma patients filtered from the database, 747 (91.3%) patients did not present ATC (INR ≤ 1.5) and 71 (8.7%) patients had ATC (INR > 1.5) upon admission to the ED. Compared to the logistic regression model, the model based on the random forest algorithm showed better accuracy (94.0%, 95% confidence interval [CI]: 0.922-0.954 to 93.5%, 95% CI: 0.916-0.95), precision (93.3%, 95% CI: 0.914-0.948 to 93.1%, 95% CI: 0.912-0.946), F1 score (93.4%, 95% CI: 0.915-0.949 to 92%, 95% CI: 0.9-0.937), and recall score (94.0%, 95% CI: 0.922-0.954 to 93.5%, 95% CI: 0.916-0.95) but yielded lower area under the receiver operating characteristic curve (AU-ROC) (0.810, 95% CI: 0.673-0.918 to 0.849, 95% CI: 0.732-0.944) for predicting ATC in the trauma patients. The result is similar in the validation cohort. The values for classification accuracy, precision, F1 score, and recall score of random forest model were 0.916, 0.907, 0.901, and 0.917, while the AU-ROC was 0.830. The values for classification accuracy, precision, F1 score, and recall score of logistic regression model were 0.905, 0.887, 0.883, and 0.905, while the AU-ROC was 0.858. We developed and validated a prediction model based on objective and rapidly accessible clinical data that very confidently identify trauma patients at risk for ATC upon their arrival to the ED. Beyond highlighting the value of ED initial laboratory tests and vital signs when used in combination with data analysis and modeling, our study illustrates a practical method that should greatly facilitates both warning and guided target intervention for ATC.

Current perspective on fibrinogen concentrate in critical bleeding

INTRODUCTION

. Massive hemorrhage continues to be a treatable cause of death. Its management varies from prefixed ratio-driven administration of blood components to goal-directed therapy based on point-of-care testing and administration of coagulation factor concentrates.

AREAS COVERED

. We review the current role of fibrinogen concentrate (FC) for the management of massive hemorrhage, either administered without coagulation testing in life-threatening hemorrhage, or within an algorithm based on viscoelastic hemostatic assays and plasma fibrinogen level. We identified relevant guidelines, meta-analyzes, randomized controlled trials, and observational studies that included indications, dosage, and adverse effects of FC, especially thromboembolic events.

EXPERT OPINION

. Moderate- to high-grade evidence supports the use of FC for the treatment of severe hemorrhage in trauma and cardiac surgery; a lower grade of evidence is available for its use in postpartum hemorrhage and end-stage liver disease. Pre-emptive FC administration in non-bleeding patients is not recommended. FC should be administered early, in a goal-directed manner, guided by early amplitude of clot firmness parameters (A5- or A10-FIBTEM) or hypofibrinogenemia. Further investigation is required into the early use of FC, as well as its potential advantages over cryoprecipitate, and whether or not its administration at high doses leads to a greater risk of adverse events.

Rotational thromboelastometry predicts transfusion and disability in pediatric trauma

BACKGROUND

Trauma-induced coagulopathy seen on rotational thromboelastometry (ROTEM) is associated with poor outcomes in adults; however, this relationship is poorly understood in the pediatric population. We sought to define thresholds for product-specific transfusion and evaluate the prognostic efficacy of ROTEM in injured children.

METHODS

Demographics, ROTEM, and clinical outcomes from severely injured children (age, < 18 years) admitted to a Level I trauma center between 2014 and 2018 were retrospectively analyzed. Receiver operating characteristic curves were plotted and Youden indexes were calculated against the endpoint of packed red blood cell transfusion to identify thresholds for intervention. The ROTEM parameters were compared against the clinical outcomes of mortality or disability at discharge.

RESULTS

Ninety subjects were reviewed. Increased tissue factor-triggered extrinsic pathway (EXTEM) clotting time (CT) >84.5 sec (p = 0.049), decreased EXTEM amplitude at 10 minutes (A10) <43.5 mm (p = 0.025), and decreased EXTEM maximal clot firmness (MCF) <64.5 mm (p = 0.026) were associated with need for blood product transfusion. Additionally, EXTEM CT longer than 68.5 seconds was associated with mortality or disability at discharge.

CONCLUSION

Coagulation dysregulation on thromboelastometry is associated with disability and mortality in children. Based on our findings, we propose ROTEM thresholds: plasma transfusion for EXTEM CT longer than 84.5 seconds, fibrinogen replacement for EXTEM A10 less than 43.5 mm, and platelet transfusion for EXTEM MCF less than 64.5 mm.

LEVEL OF EVIDENCE

Prognostic, Level III; Therapeutic, Level IV.

Point-of-Care diagnostics of coagulation in the management of bleeding and transfusion in trauma patients

PURPOSE OF REVIEW

Trauma-associated bleeding and coagulopathy require timely identification, prevention, and effective treatment. The present review summarizes the recent literature around point-of-care (POC) coagulation tests, their usefulness in the management of trauma-induced coagulopathy (TIC), their impact on trauma patient outcomes, and the requirement of quality assurance.

RECENT FINDINGS

Best practice algorithms to manage TIC have been compiled in the 2019 European Guideline on the management of major bleeding and coagulopathy after trauma. Evidence supports the use of goal-directed approaches to manage TIC. POC coagulation tests can accelerate and tailor individualized therapies. Recent findings emphasize: the time sparing of POC tests in prehospital settings and the validity of POC measurements in extreme environments; the potential scalability of POC-guided TIC algorithms in burn injuries and the pediatric population; the need for careful considerations of strategies to monitor and reverse the effects of direct oral anticoagulants in major trauma.

SUMMARY

In contrast to an abundance of reviews and practical approaches to POC coagulation management in trauma patients, there is a scarcity of research in the field and large-scale clinical trials are urgently needed. The paneuropean multicenter trial Implementing Treatment Algorithms for the Correction of Trauma Induced Coagulopathy (iTACTIC) will inform on the potential of viscoelastic tests to augment transfusion protocols for better patient outcomes.

A retrospective register study comparing fibrinogen treated trauma patients with an injury severity score matched control group

BACKGROUND

Fibrinogen concentrate (FC) is frequently used to treat bleeding trauma patients, although the clinical effects are not well known. In this study we describe demographic and clinical outcome data in a cohort of trauma patients receiving FC, compared to a matched control group, who did not receive FC.

METHODS

This retrospective, single-center, observational study included adult trauma patients admitted to a level 1-trauma center in Sweden between January 2013 and June 2015. The study population consisted of patients to whom FC was administrated within 24 h (n = 138, "Fib+"). Patients with Injury Severity Score (ISS) > 49 and/or deceased within 1 h from arrival were excluded (n = 30). Controls (n = 108) were matched for age, gender and ISS ("Fib-"). Primary outcome was mortality (24 h-/30 days-/1 year-), and secondary outcomes were blood transfusions, thromboembolic events and organ failure.

RESULTS

The Fib+ group, despite having similar ISS as Fib-, had higher prevalence of penetrating trauma and lower Glasgow Coma Scale (GCS), indicating more severe injuries. Patients receiving FC had a higher mortality after 24 h/ 30 days/ 1 year compared to controls (Fib-). However, in a propensity score matched model, the differences in mortality between Fib+ and Fib- were no longer significant. Blood transfusions were more common in the Fib+ group, but no difference was observed in thromboembolic events or organ failure. In both groups, low as well as high P-fibrinogen levels at arrival were associated with increased mortality, with the lowest mortality observed at P-fibrinogen values of 2-3 g/l.

CONCLUSIONS

Despite equal ISS, patients receiving FC had a higher mortality compared to the control group, presumably associated to the fact that these patients were bleeding and physiologically deranged on arrival. When applying a propensity score matching approach, the difference in mortality between the groups was no longer significant. No differences were observed between the groups regarding thromboembolic events or organ failure, despite higher transfusion volumes in patients receiving FC.

Cold-stored whole blood platelet function is preserved in injured children with hemorrhagic shock

BACKGROUND

Recent data demonstrate the safety of uncrossmatched cold-stored whole blood (WB) transfusion in pediatric trauma patients. The hemostatic capabilities of platelets within the cold-stored WB unit have been demonstrated via in vitro studies and animal models. However, platelet function has not been evaluated in pediatric recipients of cold-stored WB transfusions.

METHODS

Injured children, 2 years or older and 10 kg or greater with hemorrhagic shock received up to 30 mL/kg of cold-stored, low titer (<50) anti-A and -B, leukoreduced, group O- WB during their initial resuscitation. Patients were included if (1) they received WB and no conventional platelets, and (2) platelet count and thromboelastography maximum amplitude were measured both before and after transfusion. These data and relevant clinical outcomes (mortality, intensive care unit length of stay [LOS], hospital LOS and ventilator days) were compared to a historical cohort of pediatric trauma patients who received uncrossmatched red blood cells (RBC) and conventional room temperature platelets.

RESULTS

Twenty-two children were included in the study; 14 in the component cohort versus 8 in the WB cohort. Neither posttransfusion platelet count (129 × 109/L vs. 135 × 109/L) nor function (thromboelastography maximum amplitude, 59.5 mm vs. 60.2 mm) differed significantly between children receiving cold-stored platelets within the WB unit versus children who received conventional warm platelets. Median (interquartile range) weight-adjusted platelet transfusion volume in the historical cohort was 4.6 (2.5-7.7) mL/kg vs. 2.4 (1.3-4.0) mL/kg in the WB cohort (p = 0.03). There was no difference between groups in age, race, mechanism of injury, Injury Severity Score, vital signs, and severe traumatic brain injury (TBI). Outcomes, including mortality, intensive care unit LOS, hospital LOS, and ventilator days, were not significantly different between groups.

CONCLUSION

No difference was seen in posttransfusion platelet number or function in severely injured children receiving cold-stored WB platelets as compared to those receiving conventional room temperature-stored platelets. Larger cohorts are required to confirm these findings.

LEVEL OF EVIDENCE

Therapeutic, level IV.

New considerations on pathways involved in acute traumatic coagulopathy: the thrombin generation paradox

Abstract

Background

An acute traumatic coagulopathy (ATC) is observed in about one third of severely traumatized patients. This early, specific, and endogenous disorder is triggered by the association of trauma and hemorrhage. The early phase of this condition is characterized by the expression of a bleeding phenotype leading to hemorrhagic shock and the late phase by a prothrombotic profile leading to multiple organ failure. The physiopathology of this phenomenon is still poorly understood. Hypotheses of disseminated intravascular coagulation, activated protein C-mediated fibrinolysis, fibrinogen consumption, and platelet functional impairment were developed by previous authors and continue to be debated. The objective of this study was to observe general hemostasis disorders in case of ATC to confront these hypotheses.

Method

Four groups of 15 rats were compared: C, control; T, trauma; H, hemorrhage; and TH, trauma and hemorrhage. Blood samples were drawn at baseline and 90 min. Thrombin generation tests, platelet aggregometry, and standard hemostasis tests were performed.

Results

Significant differences were observed between the baseline and TH groups for aPTT (17.9 ± 0.8 s vs 24.3 ± 1.4 s, p < 0.001, mean ± SEM), MAP (79.7 ± 1.3 mmHg vs 43.8 ± 1.3 mmHg, p < 0.001, mean ± SEM), and hemoglobin (16.5 ± 0.1 g/dL vs 14.1 ± 0.3 g/dL, p < 0.001, mean ± SEM), indicating the presence of an hemorrhagic shock due to ATC. Compared to all other groups, coagulation factor activities were decreased in the TH group, but endogenous thrombin potential was (paradoxically) higher than in group C (312 ± 17 nM/min vs. 228 ± 23 nM/min; p = 0.016; mean ± SEM). We also observed a subtle decrease in platelet count and function in case of ATC and retrieved an inversed linear relationship between fibrinogen concentration and aPTT (intercept, 26.53 ± 3.16; coefficient, − 3.40 ± 1.26; adjusted R²: 0.1878; p = 0.0123).

Conclusions

The clinical-biological profile that we observed, combining normal thrombin generation, fibrinogen depletion, and a hemorrhagic phenotype, reinforced the hypothesis of activated protein C mediated-fibrinolysis. The key role of fibrinogen, but not of the platelets, was confirmed in this study. The paradoxical preservation of thrombin generation suggests a protective mechanism mediated by rhabdomyolysis in case of major trauma. Based on these results, we propose a new conception concerning the pathophysiology of ATC.

Long-term outcomes of hepatocellular carcinoma that underwent chemoembolization for bridging or downstaging

BACKGROUND

Prospective study of 200 patients with hepatocellular carcinoma (HCC) that underwent liver transplant (LT) after drug-eluting beads transarterial chemoembolization (DEB-TACE) for downstaging versus bridging. Overall survival and tumor recurrence rates were calculated, eligibility for LT, time on the waiting list and radiological response were compared. After TACE, only patients within Milan Criteria (MC) were transplanted. More patients underwent LT in bridging group. Five-year post-transplant overall survival, recurrence-free survival has no difference between the groups. Complete response was observed more frequently in bridging group. Patients in DS group can achieve post-transplant survival and HCC recurrence-free probability, at five years, just like patients within MC in patients undergoing DEB-TACE.

AIM

To determine long-term outcomes of patients with HCC that underwent LT after DEB-TACE for downstaging vs bridging.

METHODS

Prospective cohort study of 200 patients included from April 2011 through June 2014. Bridging group included patients within MC. Downstaging group (out of MC) was divided in 5 subgroups (G1 to G5). Total tumor diameter was ≤ 8 cm for G1, 2, 3, 4 (n = 42) and was > 8 cm for G5 (n = 22). Downstaging (n = 64) and bridging (n = 136) populations were not significantly different. Overall survival and tumor recurrence rates were calculated by the Kaplan-Meier method. Additionally, eligibility for LT, time on the waiting list until LT and radiological response were compared.

RESULTS

After TACE, only patients within MC were transplanted. More patients underwent LT in bridging group 65.9% (P = 0.001). Downstaging population presented: higher number of nodules 2.81 (P = 0.001); larger total tumor diameter 8.09 (P = 0.001); multifocal HCC 78% (P = 0.001); more post-transplantation recurrence 25% (P = 0.02). Patients with maximal tumor diameter up to 7.05 cm were more likely to receive LT (P = 0.005). Median time on the waiting list was significantly longer in downstaging group 10.6 mo (P = 0.028). Five-year post-transplant overall survival was 73.5% in downstaging and 72.3% bridging groups (P = 0.31), and recurrence-free survival was 62.1% in downstaging and 74.8% bridging groups (P = 0.93). Radiological response: complete response was observed more frequently in bridging group (P = 0.004).

CONCLUSION

Tumors initially exceeding the MC down-staged after DEB-TACE, can achieve post-transplant survival and HCC recurrence-free probability, at five years, just like patients within MC in patients undergoing DEB-TACE.

Early Identification of Acute Traumatic Coagulopathy Using Clinical Prediction Tools: A Systematic Review

Background and objectives: Prompt identification of patients with acute traumatic coagulopathy (ATC) is necessary to expedite appropriate treatment. An early clinical prediction tool that does not require laboratory testing is a convenient way to estimate risk. Prediction models have been developed, but none are in widespread use. This systematic review aimed to identify and assess accuracy of prediction tools for ATC. Materials and Methods: A search of OVID Medline and Embase was performed for articles published between January 1998 and February 2018. We searched for prognostic and predictive studies of coagulopathy in adult trauma patients. Studies that described stand-alone predictive or associated factors were excluded. Studies describing prediction of laboratory-diagnosed ATC were extracted. Performance of these tools was described. Results: Six studies were identified describing four different ATC prediction tools. The COAST score uses five prehospital variables (blood pressure, temperature, chest decompression, vehicular entrapment and abdominal injury) and performed with 60% sensitivity and 96% specificity to identify an International Normalised Ratio (INR) of >1.5 on an Australian single centre cohort. TICCS predicted an INR of >1.3 in a small Belgian cohort with 100% sensitivity and 96% specificity based on admissions to resuscitation rooms, blood pressure and injury distribution but performed with an Area under the Receiver Operating Characteristic (AUROC) curve of 0.700 on a German trauma registry validation. Prediction of Acute Coagulopathy of Trauma (PACT) was developed in USA using six weighted variables (shock index, age, mechanism of injury, Glasgow Coma Scale, cardiopulmonary resuscitation, intubation) and predicted an INR of >1.5 with 73.1% sensitivity and 73.8% specificity. The Bayesian network model is an artificial intelligence system that predicted a prothrombin time ratio of >1.2 based on 14 clinical variables with 90% sensitivity and 92% specificity. Conclusions: The search for ATC prediction models yielded four scoring systems. While there is some potential to be implemented effectively in clinical practice, none have been sufficiently externally validated to demonstrate associations with patient outcomes. These tools remain useful for research purposes to identify populations at risk of ATC.