Hypercoagulability following blunt solid abdominal organ injury: when to initiate anticoagulation

Similar rate of venous thromboembolism (VTE) and failure of non-operative management for early versus delayed VTE chemoprophylaxis in adolescent blunt solid organ injuries: a propensity-matched analysis

BACKGROUND

Early initiation of venous thromboembolism (VTE) chemoprophylaxis in adults with blunt solid organ injury (BSOI) has been demonstrated to be safe but this is controversial in adolescents. We hypothesized that adolescent patients with BSOI undergoing non-operative management (NOM) and receiving early VTE chemoprophylaxis (eVTEP) (≤ 48 h) have a decreased rate of VTE and similar rate of failure of NOM, compared to similarly matched adolescents receiving delayed VTE chemoprophylaxis (dVTEP) (> 48 h).

METHODS

The 2017-2019 Trauma Quality Improvement Program database was queried for adolescents (12-17 years of age) with BSOI (liver, kidney, and/or spleen) undergoing NOM. We compared eVTEP versus dVTEP using a 1:1 propensity score model, matching for age, comorbidities, BSOI grade, injury severity score, hypotension on arrival, and need for transfusions. We performed subset analyses in patients with isolated spleen, kidney, and liver injury.

RESULTS

From 1022 cases, 417 (40.8%) adolescents received eVTEP. After matching, there was no difference in matched variables (all p > 0.05). Both groups had a similar rate of VTE (dVTEP 0.6% vs. eVTEP 1.7%, p = 0.16), mortality (dVTEP 0.3% vs. eVTEP 0%, p = 0.32), and failure of NOM (eVTEP 6.7% vs. dVTEP 7.3%, p = 0.77). These findings remained true in all subset analyses of isolated solid organ injury (all p > 0.05).

CONCLUSIONS

The rate of VTE with adolescent BSOI is exceedingly rare. Early VTE chemoprophylaxis in adolescent BSOI does not increase the rate of failing NOM. However, unlike adult trauma patients, adolescent patients with BSOI receiving eVTEP had a similar rate of VTE and death, compared to adolescents receiving dVTEP.

Time to maximum amplitude of thromboelastography can predict mortality in patients with severe COVID-19: a retrospective observational study

Objective

To predict mortality in severe patients with COVID-19 at admission to the intensive care unit (ICU) using thromboelastography (TEG).

Methods

This retrospective, two-center, observational study involved 87 patients with PCR-and chest CT-confirmed severe COVID-19 who were admitted to at Wuhan Huoshenshan Hospital and the 908th Hospital of Chinese PLA Logistic Support Force between February 2020 and February 2023. Clinic demographics, laboratory results, and outcomes were compared between those who survived and those who died during hospitalization.

Results

Thromboelastography showed that of the 87 patients, 14 were in a hypercoagulable state, 25 were in a hypocoagulable state, and 48 were normal, based on the time to maximum amplitude (TMA). Patients who died showed significantly lower α angle, but significantly longer R-time, K-time and TMA than patients who survived. Random forest selection showed that K-time, TMA, prothrombin time (PT), international normalized ratio (INR), D-dimer, C-reactive protein (CRP), aspartate aminotransferase (AST), and total bilirubin (Tbil) were significant predictors. Multivariate logistic regression identified that TMA and CRP were independently associated with mortality. TMA had a greater predictive power than CRP levels based on time-dependent AUCs. Patients with TMA ≥ 26.4 min were at significantly higher risk of mortality (hazard ratio 3.99, 95% Confidence Interval, 1.92-8.27, p < 0.01).

Conclusion

TMA ≥26.4 min at admission to ICU may be an independent predictor of in-hospital mortality for patients with severe COVID-19.

Analysis of High-Risk Factors and Construction of a Nomogram Predictive Model for Deep Venous Thrombosis in Pelvic and Acetabular Fracture Patients Treated Conservatively

PURPOSE

This study aims to develop a predictive nomogram model to assist physicians in making evidence-based decisions and potentially reduce the incidence of deep venous thrombosis (DVT).

METHODS

We conducted a retrospective study, including patients admitted to the hospital from January 2014 to January 2022 with a closed, single pelvic or acetabular fracture. Comprehensive data were collected for each patient, encompassing demographics, injury characteristics, comorbidities, and results from laboratory tests and lower extremity ultrasounds. Potential risk factors were identified by univariate and multivariate logistic regression analyses. The predictive model was constructed and then internally validated. Calibration accuracy was assessed using a calibration slope and the Hosmer-Lemeshow goodness-of-fit test. The discrimination of the nomogram model was evaluated using the C-statistic.

RESULTS

Out of 232 individuals who underwent conservative treatment, 57 (24.6%) were classified into the DVT group and 175 (75.4%) into the non-DVT group based on lower extremity ultrasound findings. Predominantly, patients were aged between 41 and 65 in both groups. Body mass index (BMI) comparison showed that 54.29% (95/175) of the non-DVT group fell within the healthy weight range, while 45.61% (26/57) in the DVT group were overweight. Notably, the proportion of obesity in the DVT group was more than double that in the non-DVT group, indicating a higher DVT risk with increasing BMI (P=0.0215). Lower red blood cell (RBC) counts were observed in DVT patients compared to non-DVT ones (P<0.001). A similar pattern emerged for D-dimer, a marker for blood clot formation and dissolution, with significant differences noted (P=0.029). Multivariable analysis identified age, BMI, associated organ injury (AOI), American Society of Anesthesiologists score, hemoglobin (HGB), RBC, and D-dimer as candidate predictors. Significant variables included age (OR, 3.04; 95% CI, 1.76-5.26; P<0.001), BMI (OR, 1.97; 95% CI, 1.22-3.18; P=0.006), AOI (OR, 2.05; 95% CI, 1.07-3.95; P=0.031), and HGB (HR, 0.59; 95% CI, 0.39-0.88; P=0.010). The discrimination was 0.787, with a corrected c-index of 0.753. Calibration plots and the Hosmer-Lemeshow test indicated a good fit (P=0.7729). Decision curve analysis revealed a superior net clinical benefit when the predicted probability threshold ranged from 0.05 to 0.95.

CONCLUSIONS

We developed a nomogram predictive model, and it could act as a practical tool in clinical workflows to assist physicians in making favorable medical decisions, which potentially reduces the incidence of DVT in those patients with pelvic and acetabular fractures treated conservatively.

Rapid clearing CT-001 restored hemostasis in mice with coagulopathy induced by activated protein C

BACKGROUND

Activated protein C (APC) is one of the mechanisms contributing to coagulopathy, which is associated with high mortality. The counteraction of the APC pathway could help ameliorate bleeding. However, patients also transform frequently from a hemorrhagic state to a prothrombotic state at a later time. Therefore, a prohemostatic therapeutic intervention should take this thrombotic risk into consideration.

OBJECTIVES

CT-001 is a novel factor VIIa (FVIIa) with enhanced activity and desialylated N-glycans for rapid clearance. We assessed CT-001 clearance in multiple species and its ability to reverse APC-mediated coagulopathic blood loss.

METHODS

The N-glycans on CT-001 were characterized by liquid chromatography-mass spectrometry. Three species were used to evaluate the pharmacokinetics of the molecule. The potency and efficacy of CT-001 under APC pathway-induced coagulopathic conditions were assessed by coagulation assays and bleeding models.

RESULTS

The N-glycosylation sites of CT-001 had high occupancy of desialylated N-glycans. CT-001 exhibited 5 to 16 times higher plasma clearance in human tissue factor knockin mice, rats, and cynomolgus monkeys than wildtype FVIIa. CT-001 corrected the activated partial thromboplastin time and thrombin generation of coagulopathic plasma to normal in in vitro studies. In an APC-mediated saphenous vein bleeding model, 3 mg/kg of CT-001 reduced bleeding time in comparison with wildtype FVIIa. The correction of bleeding by CT-001 was also observed in a coagulopathic tail amputation severe hemorrhage mouse model. The efficacy of CT-001 is independent of the presence of tranexamic acid, and the combination of CT-001 and tranexamic acid does not lead to increased thrombogenicity.

CONCLUSION

CT-001 corrected APC pathway-mediated coagulopathic conditions in preclinical studies and could be a potentially safe and effective procoagulant agent for addressing APC-mediated bleeding.

Early venous thromboembolism prophylaxis in patients with trauma intracranial hemorrhage: Analysis of the prospective multicenter Consortium of Leaders in Traumatic Thromboembolism study

BACKGROUND

The optimal time to initiate venous thromboembolism prophylaxis (VTEp) for patients with intracranial hemorrhage (ICH) is controversial and must balance the risks of VTE with potential progression of ICH. We sought to evaluate the efficacy and safety of early VTEp initiation after traumatic ICH.

METHODS

This is a secondary analysis of the prospective multicenter Consortium of Leaders in the Study of Thromboembolism study. Patients with head Abbreviated Injury Scale score of > 2 and with immediate VTEp held because of ICH were included. Patients were divided into VTEp ≤ or >48 hours and compared. Outcome variables included overall VTE, deep vein thrombosis (DVT), pulmonary embolism, progression of intracranial hemorrhage (pICH), or other bleeding events. Univariate and multivariate logistic regressions were performed.

RESULTS

There were 881 patients in total; 378 (43%) started VTEp ≤48 hours (early). Patients starting VTEp >48 hours (late) had higher VTE (12.4% vs. 7.2%, p = 0.01) and DVT (11.0% vs. 6.1%, p = 0.01) rates than the early group. The incidence of pulmonary embolism (2.1% vs. 2.2%, p = 0.94), pICH (1.9% vs. 1.8%, p = 0.95), or any other bleeding event (1.9% vs. 3.0%, p = 0.28) was equivalent between early and late VTEp groups. On multivariate logistic regression analysis, VTEp >48 hours (odds ratio [OR], 1.86), ventilator days >3 (OR, 2.00), and risk assessment profile score of ≥5 (OR, 6.70) were independent risk factors for VTE (all p < 0.05), while VTEp with enoxaparin was associated with decreased VTE (OR, 0.54, p < 0.05). Importantly, VTEp ≤48 hours was not associated with pICH (OR, 0.75) or risk of other bleeding events (OR, 1.28) (both p = NS).

CONCLUSION

Early initiation of VTEp (≤48 hours) for patients with ICH was associated with decreased VTE/DVT rates without increased risk of pICH or other significant bleeding events. Enoxaparin is superior to unfractionated heparin as VTE prophylaxis in patients with severe TBI.

LEVEL OF EVIDENCE

Therapeutic/Care Management; Level IV.

Timing of venous thromboembolism prophylaxis initiation after injury: Findings from the consensus conference to implement optimal VTE prophylaxis in trauma

ABSTRACT

Optimizing prophylaxis against venous thromboembolic events (VTEs) is a critical issue in the care of injured patients. Although these patients are at significant risk of developing VTE, they also present competing concerns related to exacerbation of bleeding from existing injuries. Especially after high-risk trauma, including injuries to the abdominal solid organs, brain, and spine, trauma providers must delineate the time period in which VTE prophylaxis successfully reduces VTE rates without encouraging bleeding. Although existing data are primarily retrospective in nature and further study is required, literature supports early VTE chemoprophylaxis initiation even for severely injured patients. Early initiation is most frequently defined as <48 hours from admission but varies from <24 hours to 72 hours and occasionally refers to time from initial trauma. Prior to chemical VTE prophylaxis initiation in patients at risk for bleeding, an observation period is necessary during which injuries must show themselves to be hemostatic, either clinically or radiographically. In the future, prospective examination of optimal timing of VTE prophylaxis is necessary. Further study of specific subsets of trauma patients will allow for development of effective VTE mitigation strategies based upon collective risks of VTE and hemorrhage progression.

Timing of venous thromboembolism chemoprophylaxis using objective hemoglobin criteria in blunt solid organ injury

BACKGROUND

The purpose of this study was to evaluate the safety and efficacy of early venous thromboembolism (VTE) chemoprophylaxis following blunt solid organ injury.

METHODS

A retrospective review of patients was performed for patients with blunt solid organ injury between 2009-2019. Enoxaparin was initiated when patients had <1g/dl Hemoglobin decline over a 24 h period. These patients were then categorized by initiation: ≤48 h and >48 h.

RESULTS

There were 653 patients: 328 (50.2%) <48 h and 325 (49.8%) ≥48 h. Twenty-nine (4.4%) developed VTE. Patients in ≥48 h group suffered more frequent VTE events (6.5% vs 2.4%, p = 0.021). Non-operative failure occurred in 6 patients (1.9%) in ≥48 h group, and 5 patients (1.5%) < 48 h group. Blood transfusion following chemophrophylaxis initiation was required in 69 (21.3%) in ≥48 h group, and 46 (14.0%) in < 48 h group, occurring similarly between groups (p=0.021).

CONCLUSION

Stable hemoglobin in the first 24 h is an efficacious, objective measure that allows early initiation of VTE chemoprophylaxis in solid organ injury. This practice is associated with earlier initiation of and fewer VTE events.

Follow-up strategies for patients with splenic trauma managed non-operatively: the 2022 World Society of Emergency Surgery consensus document

Background

In 2017, the World Society of Emergency Surgery published its guidelines for the management of adult and pediatric patients with splenic trauma. Several issues regarding the follow-up of patients with splenic injuries treated with NOM remained unsolved.

Methods

Using a modified Delphi method, we sought to explore ongoing areas of controversy in the NOM of splenic trauma and reach a consensus among a group of 48 international experts from five continents (Africa, Europe, Asia, Oceania, America) concerning optimal follow-up strategies in patients with splenic injuries treated with NOM.

Results

Consensus was reached on eleven clinical research questions and 28 recommendations with an agreement rate ≥ 80%. Mobilization after 24 h in low-grade splenic trauma patients (WSES Class I, AAST Grades I–II) was suggested, while in patients with high-grade splenic injuries (WSES Classes II–III, AAST Grades III–V), if no other contraindications to early mobilization exist, safe mobilization of the patient when three successive hemoglobins 8 h apart after the first are within 10% of each other was considered safe according to the panel. The panel suggests adult patients to be admitted to hospital for 1 day (for low-grade splenic injuries—WSES Class I, AAST Grades I–II) to 3 days (for high-grade splenic injuries—WSES Classes II–III, AAST Grades III–V), with those with high-grade injuries requiring admission to a monitored setting. In the absence of specific complications, the panel suggests DVT and VTE prophylaxis with LMWH to be started within 48–72 h from hospital admission. The panel suggests splenic artery embolization (SAE) as the first-line intervention in patients with hemodynamic stability and arterial blush on CT scan, irrespective of injury grade. Regarding patients with WSES Class II blunt splenic injuries (AAST Grade III) without contrast extravasation, a low threshold for SAE has been suggested in the presence of risk factors for NOM failure. The panel also suggested angiography and eventual SAE in all hemodynamically stable adult patients with WSES Class III injuries (AAST Grades IV–V), even in the absence of CT blush, especially when concomitant surgery that requires change of position is needed. Follow-up imaging with contrast-enhanced ultrasound/CT scan in 48–72 h post-admission of trauma in splenic injuries WSES Class II (AAST Grade III) or higher treated with NOM was considered the best strategy for timely detection of vascular complications.

Conclusion

This consensus document could help guide future prospective studies aiming at validating the suggested strategies through the implementation of prospective trauma databases and the subsequent production of internationally endorsed guidelines on the issue.

Early start of thromboprophylaxis does not increase risk of intracranial hematoma progression in multiply injured patients with traumatic brain injury

BACKGROUND

Venous thromboembolism (VTE) in severely injured patients with severe traumatic brain injury (TBI) is a risk during the clinical course. Data on the safety of an early initiation of pharmacological VTE prophylaxis in severely injured patients with concomitant severe TBI is sparse.

METHODS

Admissions to our level-1-trauma center between January 2015 and December 2018 were screened. Patients suffering from severe TBI (Abbreviated Injury Scale (AIS) of the head ≥3) and at least one further AIS ≥ 3 in any other body region were included. Demographic data, thromboembolic events, and progression of the intracranial hemorrhage were extracted from the patient's charts. According to the first application of pharmacological thromboprophylaxis (VTEp), patients were categorized either to the early, the late (later than 24 h) or the no therapy group.

RESULTS

In 79 patients (early: n = 35, late: n = 29, no therapy: n = 15) the Injury Severity Score (ISS) was 36.7 ± 12.7 points (AIS_head 4.1 ± 0.8). No differences were found regarding the progression of the intracranial hemorrhage after initiation of the VTE prophylaxis (adj. p = 0.8). The VTE rate was low (n = 1, 1.6%).

CONCLUSION

In severely injured patients with severe TBI, the early administration of pharmacological thromboprophylaxis did not result in a higher rate of intracranial hematoma progression.

Optimal timing of venous thromboembolic chemoprophylaxis initiation following blunt solid organ injury: meta-analysis and systematic review

PURPOSE

The need to prevent venous thromboembolism (VTE) following blunt solid organ injury must be balanced against the concern for exacerbation of hemorrhage. The optimal timing for initiation of VTE chemoprophylaxis is not known. The objective was to determine the safety and efficacy of early (≤ 48 h) VTE chemoprophylaxis initiation following blunt solid organ injury.

METHODS

An electronic search was performed of medical libraries for English language studies on timing of VTE chemoprophylaxis initiation following blunt solid organ injury published from inception to April 2020. Included studies compared early (≤ 48 h) versus late (> 48 h) initiation of VTE chemoprophylaxis in adults with blunt splenic, liver, and/or kidney injury. Estimates were pooled using random-effects meta-analysis. Odds ratios were utilized to quantify differences in failure of nonoperative management, need for blood transfusion and rates of VTE.

RESULTS

The search identified 2,111 studies. Of these, ten studies comprising 14,675 patients were included. All studies were non-randomized and only one was prospective. The overall odds of failure of nonoperative management were no different between early and late groups, OR 1.09 (95%CI 0.92-1.29). Similarly, there was no difference in the need for blood transfusion either during overall hospital stay, OR 0.91 (95%CI 0.70-1.18), or post prophylaxis initiation, OR 1.23 (95%CI 0.55-2.73). There were significantly lower odds of VTE when patients received early VTE chemoprophylaxis, OR 0.51 (95%CI 0.33-0.81).

CONCLUSIONS

Patients undergoing nonoperative management for blunt solid organ injury can be safely and effectively prescribed early VTE chemoprophylaxis. This results in significantly lower VTE rates without demonstrable harm.

Timing of pharmacologic venous thromboembolism prophylaxis initiation for trauma patients with nonoperatively managed blunt abdominal solid organ injury: a systematic review and meta-analysis

Background

Blunt abdominal solid organ injury is common and is often managed nonoperatively. Clinicians must balance risk of both hemorrhage and thrombosis. The optimal timing of pharmacologic venous thromboembolism prophylaxis (VTEp) initiation in this population is unclear. The objective was to evaluate early (< 48 h) compared to late initiation of VTEp in adult trauma patients with blunt abdominal solid organ injury managed nonoperatively.

Methods

Embase, MEDLINE, and the Cochrane Central Register of Controlled Trials were searched from inception to March 2021. Studies comparing timeframes of VTEp initiation were considered. The primary outcome was failure of nonoperative management (NOM) after VTEp initiation. Secondary outcomes included risk of transfusion, other bleeding complications, risk of deep vein thrombosis (DVT) and pulmonary embolism, and mortality.

Results

Ten cohort studies met inclusion criteria, with a total of 4642 patients. Meta-analysis revealed a statistically significant increase in the risk of failure of NOM among patients receiving early VTEp (OR 1.76, 95% CI 1.01–3.05, p = 0.05). There was no significant difference in risk of transfusion. Odds of DVT were significantly lower in the early group (OR 0.36, 95% CI 0.22–0.59, p < 0.0001). There was no difference in mortality (OR 1.50, 95% CI 0.82–2.75, p = 0.19). All studies were at serious risk of bias due to confounding.

Conclusions

Initiation of VTEp earlier than 48 h following hospitalization is associated with an increased risk of failure of NOM but a decreased risk of DVT. Absolute failure rates of NOM are low. Initiation of VTEp at 48 h may balance the risks of bleeding and VTE.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13017-022-00423-1.

Thromboembolic complications among multiple injured patients with pelvic injuries: identifying risk factors for possible patient-tailored prophylaxis

Background

Patients with pelvic and/or acetabular fractures are at high risk of developing thromboembolic (TE) complications. In our study we investigate TE complications and the potential negative effects of concomitant pelvic or acetabular injuries in multiple injured patients according to pelvic/acetabular injury severity and fracture classification.

Methods

The TraumaRegister DGU® was analyzed between 2010 and 2019. Multiple injured patients with pelvic and/or acetabular fractures with ISS ≥ 16 suffering from TE complications were identified. We conducted a univariate and multivariate analysis with TE events as independent variable to examine potential risk factors and contributing factors.

Results

10.634 patients met our inclusion criteria. The overall TE incidence was 4.9%. Independent risk factors for the development of TE complications were sepsis, ≥ 10 operative interventions, mass transfusion (≥ 10 PRBCs), age ≥ 65 years and AIS_Abdomen ≥ 3 (all p < 0.001). No correlation was found for overall injury severity (ISS), moderate traumatic brain injury, additional injury to lower extremities, type B and C pelvic fracture according to Tile/AO/OTA and closed or open acetabular fracture.

Conclusions

Multiple injured patients suffering from pelvic and/or acetabular fractures are at high risk of developing thromboembolic complications. Independent risk factors for the development of thromboembolic events in our study cohort were age ≥ 65 years, mass transfusion, AIS_Abdomen ≥ 3, sepsis and ≥ 10 surgery procedures. Among multiple injured patients with acetabular or pelvic injuries the severity of these injuries seems to have no further impact on thromboembolic risk. Our study, however, highlights the major impact of early hemorrhage and septic complications on thromboembolic risk in severely injured trauma patients. This may lead to individualized screening examinations and a patient-tailored thromboprophylaxis in high-risk patients for TE. Furthermore, the number of surgical interventions should be minimized in these patients to reduce thromboembolic risk.

Viscoelastic monitoring in trauma resuscitation

BACKGROUND

Traumatic injury results in both physical and physiologic insult. Successful care of the trauma patient depends upon timely correction of both physical and biochemical injury. Trauma-induced coagulopathy is a derangement of hemostasis and thrombosis that develops rapidly and can be fatal if not corrected. Viscoelastic monitoring (VEM) assays have been developed to provide rapid, accurate, and relatively comprehensive depictions of an individual's coagulation profile. VEM are increasingly being integrated into trauma resuscitation guidelines to provide dynamic and individualized guidance to correct coagulopathy.

STUDY DESIGN AND METHODS

We performed a narrative review of the search terms viscoelastic, thromboelastography, thromboelastometry, TEG, ROTEM, trauma, injury, resuscitation, and coagulopathy using PubMed. Particular focus was directed to articles describing algorithms for management of traumatic coagulopathy based on VEM assay parameters.

RESULTS

Our search identified 16 papers with VEM-guided resuscitation strategies in adult patients based on TEG, 12 such protocols in adults based on ROTEM, 1 protocol for children based on TEG, and 2 protocols for children based on ROTEM.

CONCLUSIONS

This review presents evidence to support VEM use to detect traumatic coagulopathy, discusses the role of VEM in trauma resuscitation, provides a summary of proposed treatment algorithms, and discusses pending questions in the field.

The association of ABO blood groups and trauma outcomes: A retrospective analysis of 3779 patients

Background:

There is currently a lack of understanding regarding the link between ABO blood types with outcomes of traumatically injured patients. The purpose of this study was to determine the association of ABO blood types with outcomes in traumatically injured patients separated by injury type.

Methods:

This retrospective study evaluated trauma patients at an urban, Level 1 trauma center from January 1, 2017, through December 31, 2017. Patients were excluded if they were pregnant or <16 years old. Recorded outcomes included: ABO blood group, mortality, Injury Severity Score (ISS), race, injury type, mechanism of injury, and complications. Data analysis was performed using descriptive statistics including Chi-squared, Kruskal–Wallis, and F-test calculations.

Results:

A total of 3779 patients were included in this study. No significant differences were present in mean age or ISS between blood types. In patients with penetrating injuries, blood type O was associated with a significant increase in mortality (P = 0.017), red blood cell transfusion (P = 0.027), and massive transfusion protocol (MTP) (P = 0.026) compared to non-O blood types. In patients with blunt injuries, blood type AB was associated with a significant increase in mortality rate compared to non-AB blood types (P = 0.03).

Conclusion:

ABO blood type is connected with an underlying process which affects trauma outcomes, including mortality. Blood type O is associated with increased blood transfusion, MTP, and mortality during the initial hospitalization following a traumatic penetrating injury, while blood type AB is associated with increased mortality during the initial hospitalization following a blunt traumatic injury.

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.

Venous thromboembolism prophylaxis in the trauma intensive care unit: an American Association for the Surgery of Trauma Critical Care Committee Clinical Consensus Document

Venous thromboembolism (VTE) is a potential sequela of injury, surgery, and critical illness. Patients in the Trauma Intensive Care Unit are at risk for this condition, prompting daily discussions during patient care rounds and routine use of mechanical and/or pharmacologic prophylaxis measures. While VTE rightfully garners much attention in clinical patient care and in the medical literature, optimal strategies for VTE prevention are still evolving. Furthermore, trauma and surgical patients often have real or perceived contraindications to prophylaxis that affect the timing of preventive measures and the consistency with which they can be applied. In this Clinical Consensus Document, the American Association for the Surgery of Trauma Critical Care Committee addresses several practical clinical questions pertaining to specific or unique aspects of VTE prophylaxis in critically ill and injured patients.

Timing of thromboprophylaxis in patients with blunt abdominal solid organ injuries undergoing nonoperative management

BACKGROUND

Decision making regarding the optimal timing for initiating thromboprophylaxis in patients with blunt abdominal solid organ injuries (BSOIs) remains ill-defined, with no guidelines defining optimal timing. In this study, we aimed to evaluate the relationship of the timing of thromboprophylaxis with thromboembolic and bleeding complications in the setting of BSOIs.

METHODS

A retrospective analysis of the Trauma Quality Improvement Program database was performed between 2013 and 2016. All patients with isolated BSOIs (liver, spleen, pancreas, or kidney, Abbreviated Injury Scale score, <3 in other regions) who underwent initial nonoperative management (NOM) were included. Patients were divided into three groups (early, <48 hours; intermediate, 48-72 hours; and late, >72 hours) based on timing of thromboprophylaxis initiation. Primary outcomes were rates of thromboembolism and bleeding after thromboprophylaxis initiation.

RESULTS

Of the 25,118 patients with isolated BSOIs, 3,223 met the inclusion criteria (age, 38.7 ± 17.3 years; males, 2.082 [64.6%]), among which 1,832 (56.8%) received early thromboprophylaxis, 703 (21.8%) received intermediate thromboprophylaxis, and 688 (21.4%) received late thromboprophylaxis. Late thromboprophylaxis initiation was independently associated with a higher likelihood of both deep vein thrombosis (odds ratio [OR], 3.15; 95% confidence interval [CI], 1.68-5.91, p < 0.001) and pulmonary embolism (OR, 4.29; 95% CI, 1.95-9.42; p < 0.001). Intermediate thromboprophylaxis initiation was independently associated with a higher likelihood of deep venous thrombosis (OR, 2.38; 95% CI, 1.20-4.74; p = 0.013), but not pulmonary embolism (p = 0.960) compared with early initiation. Early (but not intermediate) thromboprophylaxis initiation was independently associated with a higher likelihood of bleeding (OR, 2.05; 95% CI, 1.11-2.18; p = 0.023), along with a history of diabetes mellitus, splenic, and high-grade liver injuries.

CONCLUSION

Early thromboprophylaxis should be considered in patients with BSOIs undergoing nonoperative management who are at low likelihood of bleeding. An intermediate delay (48-72 hours) of thromboprophylaxis should be considered for patients with diabetes mellitus, splenic injuries, and Grades 3 to 5 liver injuries.

LEVEL OF EVIDENCE

Therapeutic, Level IV.

Timing and Type of Venous Thromboembolic Prophylaxis in Isolated Severe Liver Injury Managed Non-Operatively

BACKGROUND

The optimal timing and type of pharmacological venous thromboembolic prophylaxis (VTEp) after severe liver injury selected for nonoperative management (NOM) are controversial. The aim of this study was to assess the effect of timing and type of VTEp in severe liver injuries selected for NOM.

METHODS

ACS-TQIP database study (2013-17) including patients with blunt isolated severe liver injuries (AIS ≥ 3), selected for NOM, who received VTEp with either unfractionated heparin (UH) or low-molecular-weight heparin (LMWH). Patients who underwent laparotomy or angiointervention within 24 h or prior to the initiation of VTEp were excluded. The study population was stratified according to the timing of VTEp ≤ 48 h (EP) and > 48 h (LP) groups. Univariate and multivariate analyses were used to identify differences between the groups.

RESULTS

A total of 4074 patients was included in the study. 2004 (49.2%) received EP and 2070 (50.8%) LP. Patients with more severe injuries were more likely to receive LP than an EP [ISS 24 (19-29) vs 22 (17-27), p < 0.001]. On multivariate analysis (correcting for age, gender, comorbidities, blood pressure, GCS, ISS, type of VTEp), LP was identified as an independent risk factor for thromboembolic events (OR 1.52, p = 0.032) and mortality (OR 2.49, p = 0.031). LMWH was independently associated with lower mortality (OR 0.36, p = 0.007), compared to UH. EP did not increase the risk of laparotomy or angiointervention after starting VTEp, compared to LP (p = 0.992).

CONCLUSION

Early VTEp (≤ 48 h) is safe and independently associated with fewer thromboembolic events and a lower mortality after isolated severe liver injuries managed nonoperatively. LMWH was independently associated with improved outcomes when compared with UH.

Treatment of blunt cerebrovascular injuries: Anticoagulants or antiplatelet agents?

BACKGROUND

Blunt cerebrovascular injury (BCVI) is associated with cerebrovascular accidents (CVA). Early therapy with antiplatelet agents or anticoagulants is recommended. There are limited data comparing the effectiveness of these treatments. The aim of our study was to compare outcomes between BCVI patients who received anticoagulants versus those who received antiplatelet agents.

METHODS

We performed an (2011-2015) analysis of the Nationwide Readmission Database and included all adult trauma patients 18 years or older who had an isolated BCVI (other body regions Abbreviated Injury Scale [AIS] < 3). Head injury patients or those who developed a CVA during the index admission were excluded. Patients were stratified into anticoagulants and antiplatelet agents. Propensity score matching was performed (1:1 ratio) to control for demographics, comorbidities, BCVI grade, distribution, and severity of injuries. Outcomes were readmission with CVA and mortality within 6 months.

RESULTS

A total of 725 BCVI patients were identified. A matched cohort of 370 patients (antiplatelet agents, 185; anticoagulants, 185) was obtained. Mean age was 50 ± 15 years, neck AIS was 3 (3,4), and Injury Severity Score was 12 (9-17). The majority of the patients (69%) had high-grade BCVI (AIS ≥ 3). Overall, 3.7% were readmitted with CVA and 3% died within 6 months. Patients who received anticoagulants had a lower rate of readmission with CVA (1.8% vs. 5.72%; p = 0.03), and a lower rate of 6-month mortality (1.3% vs. 4.9%; p = 0.03). There was no significant difference between the two groups reading the median time to stroke (9 days vs. 6 days; p = 0.12).

CONCLUSION

The BCVI patients on CVA prophylaxis for BCVI have a 3.7% rate of stroke after discharge. Compared with antiplatelet agents, anticoagulants are associated with lower rates of CVA in the first 6-month postdischarge. Further studies are required to identify the optimal agent to prevent CVA in this high-risk subset of trauma patients.

LEVEL OF EVIDENCE

Therapeutic, level IV.

When is It Safe to Start VTE Prophylaxis After Blunt Solid Organ Injury? A Prospective Study from a Level I Trauma Center

BACKGROUND

The optimal timing of VTE prophylaxis initiation after blunt solid organ injury is controversial. Retrospective studies suggest initiation ≤48 h is safe. This prospective study examined the safety and efficacy of early VTE prophylaxis initiation after nonoperative blunt solid organ injury.

METHODS

All patients >15 years of age presenting after blunt trauma (12/01/16-11/30/17) were prospectively screened. Patients were included if solid organ injury (liver, spleen, kidney) was diagnosed on admission CT scan and nonoperative management was planned. ED deaths, transfers, patients with pre-existing bleeding disorders or home antiplatelet/anticoagulant medications, and those who did not receive VTE prophylaxis were excluded. Demographics, injury/clinical data, type/timing of VTE prophylaxis initiation, and outcomes were collected. Patients were dichotomized into study groups based on VTE prophylaxis initiation time: Early (≤48 h) vs Late (>48 h after admission). Prophylaxis initiation was at the discretion of the attending trauma surgeon. The primary study outcome was VTE event rate. Secondary outcomes included hospital length of stay (LOS), intensive care unit (ICU) LOS, need for and volume of post-prophylaxis blood transfusion, need for delayed (post-prophylaxis) interventional radiology (IR) or operative intervention, failure of nonoperative management, and mortality. Outcomes were compared with univariate analysis. Multivariate analysis with logistic regression determined independent predictors of late VTE prophylaxis initiation.

RESULTS

After exclusions, 118 patients were identified. Median ISS was 22 [IQR 14-26]. Median AAST grade of injury was 2 [IQR 2-3] for liver, 2 [IQR 1-3] for spleen, and 3 [IQR 2-3] for kidney. Compared to late prophylaxis patients (n = 57, 48%), early prophylaxis patients (n = 61, 52%) had significantly fewer DVTs (n = 0, 0% vs n = 5, 9%, p = 0.024) but similar rates of PE (n = 2, 3% vs n = 3, 5%, p = 0.672). TBI was the only significant risk factor for late prophylaxis (OR 0.22, p = 0.015). No patient in either group required delayed intervention (operative or IR) for bleeding. There was no difference in volume of post-prophylaxis blood transfusion.

CONCLUSIONS

In this prospective study of patients with nonoperative blunt solid organ injuries, early (≤48 h) initiation of VTE prophylaxis resulted in a lower incidence of DVTs without an associated increase in bleeding or need for intervention. Early initiation of VTE prophylaxis is likely to be safe and beneficial for patients with blunt solid organ injury.

Is early chemical thromboprophylaxis in patients with solid organ injury a solid decision?

BACKGROUND

The optimal time to initiate chemical thromboprophylaxis (CTP) in patients who have undergone nonoperative management (NOM) of blunt solid organ injuries (SOI) remains controversial. The aim of our study was to assess the impact of early initiation of CTP in patients with blunt abdominal SOIs.

METHODS

We performed a 2-year (2013-2014) retrospective analysis of American College of Surgeons Trauma Quality Improvement Program. We included all adult trauma patients (age, ≥ 18 years) with blunt SOI who underwent NOM. Patients were stratified into three groups based on timing of CTP (early, ≤48 hours of injury; late, >48 hours of injury,; and no prophylaxis group). Our primary outcomes were rates of failure of NOM, pRBC transfusion, and mortality. Our secondary outcomes were the rate of venous thromboembolic (VTE) events (i.e., deep venous thrombosis [DVT] and/or pulmonary embolism [PE]) and length of stay.

RESULTS

A total of 36,187 patients met the inclusion criteria. Mean age was 49.5 ± 19 years and 36% of patients received CTP (early, 37% (n = 4,819) versus late, 63% (n = 8,208)). After controlling for confounders, patients receiving early CTP had lower rates of DVT (p = 0.01) and PE (p = 0.01) compared with the no prophylaxis and late CTP groups. There was no difference between the three groups regarding the postprophylaxis pRBC transfusions, failure of NOM, and mortality.

CONCLUSION

Our results suggest that in patients undergoing NOM of blunt abdominal SOI, early initiation of CTP should be considered. It is associated with decreased rates of DVT and PE, with no significant difference in post prophylaxis pRBC transfusion, failure of nonoperative management, and mortality.

LEVEL OF EVIDENCE

Therapeutic, level V.

Not all in your head (and neck): Stroke after blunt cerebrovascular injury is associated with systemic hypercoagulability

BACKGROUND

Stroke secondary to blunt cerebrovascular injury (BCVI) most often occurs before initiation of antithrombotic therapy. Earlier treatment, especially in multiply injured patients with relative contraindications to antithrombotic agents, could be facilitated with improved risk stratification; furthermore, the relationship between BCVI-attributed stroke and hypercoagulability remains unknown. We hypothesized that patients who suffer BCVI-related stroke are hypercoagulable compared with those with BCVI who do not stroke.

METHODS

Rapid thromboelastography (TEG) was evaluated for patients with BCVI-attributed stroke at an urban Level I trauma center from 2011 to 2018. Contemporary controls who had BCVI but did not stroke were selected for comparison using propensity-score matching with 20% caliper that accounted for age, sex, injury severity, and BCVI location and grade.

RESULTS

During the study period, 15,347 patients were admitted following blunt trauma. Blunt cerebrovascular injury was identified in 435 (3%) patients, of whom 28 experienced associated stroke and had a TEG within 24 hours of arrival. Forty-nine patients who had BCVI but did not suffer stroke served as matched controls. Stroke patients formed clots faster as evident in their larger angle (77.5 degrees vs. 74.6 degrees, p = 0.03) and had greater clot strength as indicated by their higher maximum amplitude (MA) (66.9 mm vs. 61.9 mm, p < 0.01). Activated clotting time was shorter among stroke patients but not significantly (113 seconds vs. 121 seconds, p > 0.05). Increased angle and elevated MA were significant predictors of stroke with odds ratios of 2.97 for angle greater than 77.3 degrees and 4.30 for MA greater than 63.0 mm.

CONCLUSION

Patients who suffer BCVI-related stroke are hypercoagulable compared with those with BCVI who remain asymptomatic. Increased angle or MA should be considered when assessing the risk of thrombosis and determining the optimal time to initiate antithrombotic therapy in patients with BCVI.

LEVEL OF EVIDENCE

Prognostic, Level III.

Pathophysiological Response to Trauma-Induced Coagulopathy: A Comprehensive Review

Hypercoagulability can occur after severe tissue injury, that is likely related to tissue factor exposure and impaired endothelial release of tissue plasminogen activator (tPA). In contrast, when shock and hypoperfusion occur, activation of the protein C pathway and endothelial tPA release induce a shift from a procoagulant to a hypocoagulable and hyperfibrinolytic state with a high risk of bleeding. Both thrombotic and bleeding phenotypes are associated with increased mortality and are influenced by the extent and severity of tissue injury and degree of hemorrhagic shock. Response to trauma is a complex, dynamic process in which risk can shift from bleeding to thrombosis depending on the injury pattern, hemostatic treatment, individual responses, genetic predisposition, and comorbidities. Based on this body of knowledge, we will review and consider future directions for the management of severely injured trauma patients.

Thromboelastography Detects Possible Coagulation Disturbance in Pediatric Patients with Portal Cavernoma

Background

Thromboelastography (TEG) allows a dynamic assessment of clot formation and dissolution that might be useful for assessing the relative contribution of the coagulation components to overall clot formation and dissolution, but it has not been fully defined in patients with portal cavernoma (PC).

Methods

We retrospectively recruited consecutive patients with PC between July 2006 and June 2016 who had no abdominal malignancy or liver cirrhosis. Blood samples were drawn on admission and were subjected to coagulation parameter assessment, including conventional coagulation tests, measurement of the circulating levels of procoagulant and anticoagulant factors, and TEG assessment.

Results

Compared with controls, patients with PC showed significant reductions in the serum levels of procoagulant factors and anticoagulants factors, whereas factor VIII was slightly elevated. TEG showed clot formation (α-angle), and the maximal clot strength (MA) was higher in patients with PC than in controls, indicating a hypercoagulable state. Thrombocytopenia decreased both clot formation (α-angle) and the maximal clot strength (MA) but was still significantly higher than the control. Furthermore, patients with PC had a higher level of D-dimer and LY30 than did controls, indicating the in vivo activation of coagulation and fibrinolysis.

Conclusion

TEG analysis showed that patients with PC were in a hypercoagulable state that could be partially masked by thrombocytopenia secondary to splenomegaly and hypersplenism in these patients, which indicates that our current prophylaxis and therapy regimen could be improved.

It's sooner than you think: Blunt solid organ injury patients are already hypercoagulable upon hospital admission - Results of a bi-institutional, prospective study

INTRODUCTION

The optimal time to initiate venous thromboembolism (VTE) chemoprophylaxis in blunt solid organ injury (BSOI) patients is debated. We hypothesize that 1) BSOI patients are hypercoagulable within 12 h of injury and 2) hypercoagulability dominates in patients who develop clot complications (CC).

MATERIAL AND METHODS

This is a prospective study of BSOI patients admitted to two Level-1 Trauma Centers' trauma intensive care units (ICU). Serial kaolin thrombelastography (TEG) and tissue plasminogen activator (tPA)-challenge TEGs were performed. CC included VTE and cerebrovascular accidents.

RESULTS

On ICU admission, all patients (n = 95) were hypercoagulable, 58% were in fibrinolysis shutdown, and 50% of patients were tPA-resistant. Twelve patients (13%) developed CC. Compared to those without CC, they demonstrated decreased fibrinolysis at 12 h and higher clot strength at 48 h CONCLUSIONS: BSOI patients are universally hypercoagulable upon ICU admission. VTE chemoprophylaxis should be started immediately in BSOI patients with hypercoagulability on TEG.

Dynamic coagulability after injury: Is delaying venous thromboembolism chemoprophylaxis worth the wait?

BACKGROUND

Severely injured patients often progress from early hypocoagulable to normal and eventually hypercoagulable states, developing increased risk for venous thromboembolism (VTE). Prophylactic anticoagulation can decrease this risk, but its initiation is frequently delayed for extended periods due to concerns for bleeding. To facilitate timely introduction of VTE chemoprophylaxis, we characterized the transition from hypo- to hypercoagulability and hypothesized that trauma-induced coagulopathy resolves within 24 hours after injury.

METHODS

Serial blood samples were collected prospectively from critically injured patients for 120 hours after arrival at an urban Level I trauma center. Extrinsic thromboelastometry maximum clot firmness was used to classify patients as hypocoagulable (HYPO, <49 mm), normocoagulable (NORM, 49-71 mm), or hypercoagulable (HYPER, >71 mm) at each time point. Changes in coagulability over hospital course, VTE occurrence, and timing of prophylaxis initiation were analyzed.

RESULTS

898 patients (median Injury Severity Score, 13; mortality, 12%; VTE, 8%) were enrolled. Upon arrival, 3% were HYPO (90% NORM, 7% HYPER), which increased to 9% at 6 hours before down-trending. Ninety-seven percent were NORM by 24 hours, and 53% were HYPER at 120 hours. Median maximum clot firmness began in the NORM range, up-trended gradually, and entered the HYPER range at 120 hours. Patients with traumatic brain injury (TBI) followed a similar course and were not more HYPO at any time point than those without TBI. Failure to initiate prophylaxis by 72 hours was predicted by TBI and associated with VTE development (27% vs 16%, p < 0.05).

CONCLUSIONS

Regardless of injury pattern, trauma-induced coagulopathy largely resolves within 24 hours, after which hypercoagulability becomes increasingly more prevalent. Deferring initiation of chemoprophylaxis, which is often biased toward patients with intracranial injuries, is associated with VTE development.

LEVEL OF EVIDENCE

Prognostic study, level III; Therapeutic, level IV.

BET 2: Is early chemical thromboprophylaxis safe in patients with blunt trauma solid organ injury (SOI) undergoing non-operative management (NOM)?

A short cut review was carried out to establish whether chemical thromboprophylaxis was a safe early intervention in patients with solid organ injury that is being managed non-operatively. Eight papers presented the best evidence to answer the clinical question. The author, date and country of publication, patient group studied, study type, relevant outcomes, results and study weaknesses of these papers are tabulated. It is concluded that there is inadequate evidence assessing safety of low molecular weight heparin (LMWH) within 24 hours of trauma. The current available evidence does suggest that administration of LMWH within 48 hours is safe in non-operative management of patients who have sustained solid organ injury from blunt trauma.

Targeting resuscitation to normalization of coagulating status: Hyper and hypocoagulability after severe injury are both associated with increased mortality

INTRODUCTION

The prevalence and impact of hypercoagulability (hypo) in severely injured patients early after injury remains unclear. We hypothesize that the predominant phenotype of postinjury coagulopathy is hypercoagulability (hyper) and it is associated with increased mortality.

MATERIAL AND METHODS

Blood samples from 141 healthy volunteers assayed with thrombelastography (TEG) were used to identify thresholds of hypo and hypercoagulability (above 95th/below the 5thpercentile) in four TEG indices. These cutoffs were subsequently evaluated in severely injured trauma patients (ISS>15) from two level 1 trauma centers.

RESULTS

2540 patients with a median ISS of 25 were analyzed. Normal TEG was present in 36% of patients. Hyper was found in 38% of patients, with mixed (11%) and hypo (15%) being less common. Compared to normal coagulation patients and after controlling for age, sex, blood pressure, and injury hyper (0.013), mixed (p < 0.001) and hypo (p < 0.001) were all independent predictors of mortality.

CONCLUSION

These data support the ongoing need for goal directed resuscitation in trauma patients, it appears the optimal resuscitation strategy should be targeted towards normalization of coagulation status as both early hyper and hypocoagulability are associated with increased mortality.

Time is now: venous thromboembolism prophylaxis in blunt splenic injury

BACKGROUND

The safety and timing of venous thromboembolism (VTE) prophylaxis in patients with blunt splenic injuries is not well known. We hypothesized that early initiation of VTE prophylaxis does not increase failure of nonoperative management or transfusion requirements in these patients.

METHODS

A retrospective review of trauma patients with blunt splenic injury was performed. Patients were compared based on initiation and timing of VTE prophylaxis (<24 hours, 24 to 48 hours, 48 to 72 hours, and >72 hours). Patients who received VTE prophylaxis were matched with those who did not. Primary outcomes included were operation or angioembolization.

RESULTS

A total of 497 patients (256 received VTE prophylaxis and 241 did not) were included. There was no difference in the number of interventions based on presence of or time to VTE prophylaxis initiation.

CONCLUSIONS

Early initiation (<48 hours) of VTE prophylaxis is safe in patients with blunt splenic injuries treated nonoperatively, and may be safe as early as 24 hours.

Very early initiation of chemical venous thromboembolism prophylaxis after blunt solid organ injury is safe

BACKGROUND

The optimal timing of initiating low-molecular weight heparin (LMWH) in patients who have undergone nonoperative management (NOM) of blunt solid organ injuries (SOIs) remains controversial. We describe the safety of early initiation of chemical venous thromboembolism (VTE) prophylaxis among patients undergoing NOM of blunt SOIs.

METHODS

We retrospectively studied severely injured adults who sustained blunt SOI without significant intracranial hemorrhage and underwent an initial NOM at a Canadian lead trauma hospital between 2010 and 2014. Safety was assessed based on failure of NOM, defined as the need for operative intervention, in patients who received early (< 48 h) or late LMWH (≥ 48 h, or early discharge [< 72 h] without LMWH).

RESULTS

We included 162 patients in our analysis. Most were men (69%), and the average age was 42 ± 18 years. The median injury severity score was 17, and splenic injuries were most common (97 [60%], median grade 2), followed by liver (57 [35%], median grade 2) and kidney injuries (31 [19%], median grade 1). Combined injuries were present in 14% of patients. A total of 78 (48%) patients received early LMWH, while 84 (52%) received late LMWH. The groups differed only in percent of high-grade splenic injury (14% v. 32%). Overall 2% of patients failed NOM, none after receiving LMWH. Semielective angiography was performed in 23 (14%) patients. The overall rate of confirmed VTE on imaging was 1.9%.

CONCLUSION

Early initiation of medical thromboembolic prophylaxis appears safe in select patients with isolated SOI following blunt trauma. A prospective multicentre study is warranted.

Global assays of hemostasis

PURPOSE OF REVIEW

There exists an imbalance between our understanding of the physiology of the blood coagulation process and the translation of this understanding into useful assays for clinical application. As technology advances, the capabilities for merging the two areas have become more attainable. Global assays have advanced our understanding of the dynamics of the blood coagulation process beyond end point assays and are at the forefront of implementation in the clinic.

RECENT FINDINGS

We will review recent advances in the main global assays with a focus on thrombin generation that have potential for clinical utility. These assays include direct (thrombogram, whole blood, purified systems) and indirect empirical measures of thrombin generation (thromboelastography) and mechanism-based computational models that use plasma composition data from individuals to generate thrombin generation profiles.

SUMMARY

Empirical thrombin generation assays (direct and indirect) and computational modeling of thrombin generation have greatly advanced our understanding of the hemostatic balance. Implementation of these types of assays and visualization approaches in the clinic will potentially provide a basis for the development of individualized patient care. Advances in both empirical and computational global assays have made the goal of predicting precrisis changes in an individual's hemostatic state one step closer.

Thromboelastometry and organ failure in trauma patients: a prospective cohort study

INTRODUCTION

Data on the incidence of a hypercoagulable state in trauma, as measured by thromboelastometry (ROTEM), is limited and the prognostic value of hypercoagulability after trauma on outcome is unclear. We aimed to determine the incidence of hypercoagulability after trauma, and to assess whether early hypercoagulability has prognostic value on the occurrence of multiple organ failure (MOF) and mortality.

METHODS

This was a prospective observational cohort study in trauma patients who met the highest trauma level team activation. Hypercoagulability was defined as a G value of ≥ 11.7 dynes/cm(2) and hypocoagulability as a G value of <5.0 dynes/cm(2). ROTEM was performed on admission and 24 hours later.

RESULTS

A total of 1,010 patients were enrolled and 948 patients were analyzed. Median age was 38 (interquartile range (IQR) 26 to 53), 77% were male and median injury severity score was 13 (IQR 8 to 25). On admission, 7% of the patients were hypercoagulable and 8% were hypocoagulable. Altogether, 10% of patients showed hypercoagulability within the first 24 hours of trauma. Hypocoagulability, but not hypercoagulability, was associated with higher sequential organ failure assessment scores, indicating more severe MOF. Mortality in patients with hypercoagulability was 0%, compared to 7% in normocoagulable and 24% in hypocoagulable patients (P <0.001). EXTEM CT, alpha and G were predictors for occurrence of MOF and mortality.

CONCLUSIONS

The incidence of a hypercoagulable state after trauma is 10% up to 24 hours after admission, which is broadly comparable to the rate of hypocoagulability. Further work in larger studies should define the clinical consequences of identifying hypercoagulability and a possible role for very early, targeted use of anticoagulants.

Effect of thromboelastography (TEG®) and rotational thromboelastometry (ROTEM®) on diagnosis of coagulopathy, transfusion guidance and mortality in trauma: descriptive systematic review

Introduction

The understanding of coagulopathies in trauma has increased interest in thromboelastography (TEG®) and thromboelastometry (ROTEM®), which promptly evaluate the entire clotting process and may guide blood product therapy. Our objective was to review the evidence for their role in diagnosing early coagulopathies, guiding blood transfusion, and reducing mortality in injured patients.

Methods

We considered observational studies and randomized controlled trials (MEDLINE, EMBASE, and Cochrane databases) to February 2014 that examined TEG®/ROTEM® in adult trauma patients. We extracted data on demographics, diagnosis of early coagulopathies, blood transfusion, and mortality. We assessed methodologic quality by using the Newcastle-Ottawa scale (NOS) for observational studies and QUADAS-2 tool for diagnostic accuracy studies.

Results

Fifty-five studies (12,489 patients) met inclusion criteria, including 38 prospective cohort studies, 15 retrospective cohort studies, two before-after studies, and no randomized trials. Methodologic quality was moderate (mean NOS score, 6.07; standard deviation, 0.49). With QUADAS-2, only three of 47 studies (6.4%) had a low risk of bias in all domains (patient selection, index test, reference standard and flow and timing); 37 of 47 studies (78.8%) had low concerns regarding applicability. Studies investigated TEG®/ROTEM® for diagnosis of early coagulopathies (n = 40) or for associations with blood-product transfusion (n = 25) or mortality (n = 24). Most (n = 52) were single-center studies. Techniques examined included rapid TEG® (n =12), ROTEM® (n = 18), TEG® (n = 23), or both TEG® and rapid TEG® (n = 2). Many TEG®/ROTEM® measurements were associated with early coagulopathies, including some (hypercoagulability, hyperfibrinolysis, platelet dysfunction) not assessed by routine screening coagulation tests. Standard measures of diagnostic accuracy were inconsistently reported. Many abnormalities predicted the need for massive transfusion and death, but predictive performance was not consistently superior to routine tests. One observational study suggested that a ROTEM®-based transfusion algorithm reduced blood-product transfusion, but TEG®/ROTEM®-based resuscitation was not associated with lower mortality in most studies.

Conclusions

Limited evidence from observational data suggest that TEG®/ROTEM® tests diagnose early trauma coagulopathy and may predict blood-product transfusion and mortality in trauma. Effects on blood-product transfusion, mortality, and other patient-important outcomes remain unproven in randomized trials.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0518-9) contains supplementary material, which is available to authorized users.