Venous thromboembolism after severe trauma: incidence, risk factors and outcome

Venous thromboembolism in transfer trauma patients: A global problem

BACKGROUND

As air travel and immobility are risk factors for venous thromboembolism, we aimed to test the hypothesis that internationally transferred trauma patients have a high incidence of venous thromboembolism on arrival.

METHODS

A prospectively maintained registry of all international transferred trauma patients who presented to our level I trauma center from January 2023 to June 2024 was retrospectively reviewed. Patients with either lower extremity venous duplex ultrasound or computed tomography scan of the chest with contrast on arrival were included. The primary outcome was venous thromboembolism, either deep venous thrombosis or pulmonary embolism.

RESULTS

There were 161 consecutive internationally transferred trauma patients; 93% had a screening venous duplex ultrasound on arrival, and 52% had a computed tomography scan of the chest with contrast. Average time from injury to arrival was 3.3 ± 4.3 days. Of those who had screening imaging, 6% had a deep venous thrombosis and 8.3% had a pulmonary embolism. Average Greenfield risk assessment profile was greater for those with than without deep venous thrombosis (10 vs 8, P = .024) and pulmonary embolism (12 vs 8, P = .001). There was no difference in days from injury or flight time for those with or without deep venous thrombosis or for those with or without pulmonary embolism.

CONCLUSION

To our knowledge, this is the first study to demonstrate a 6-8% incidence of venous thromboembolism on arrival in international transfer trauma patients. New protocols should include risk stratification for early thromboprophylaxis in transferring centers and screening admission venous duplex ultrasound and computed tomography scan of the chest at receiving centers.

Audit of VTE prophylaxis prescribing preferences among orthopaedic consultants in Irish orthopaedic trauma centres

BACKGROUND

Thromboembolic complications are common in trauma orthopaedic practise. Despite extensive research, there remain a number of unanswered questions regarding the use of thromboprophylaxis.

AIMS

To establish the current practise among Irish consultant orthopaedic surgeons regarding thromboprophylaxis.

METHODS

A confidential online questionnaire regarding VTE prophylaxis was circulated to all consultant orthopaedic surgeons in training hospitals in the Republic of Ireland. Questions investigated surgeon awareness of local/national guidelines, inpatient and outpatient prescribing preferences and agreement/disagreement with the statement that defensive medicine, rather than evidence-based medicine, has driven increased emphasis on VTE prophylaxis in Ireland in recent years.

RESULTS

The response rate was 72% (69/96). 72% (50/79) of surgeons were aware of local VTE prophylaxis guidelines. 38% (29/96) were aware of national guidelines. 89% (62/69) routinely used mechanical prophylaxis modalities. 73.9% (51/69) routinely used chemical prophylaxis for inpatients. However, this practise was z extremely heterogenous with five other pharmacological agents used by the remainder. 82.6% (57/69) routinely discharged patients on extended duration chemical prophylaxis. 67% (46/69) agreed that the recent increased emphasis on VTE prophylaxis was due to defensive medicine and not evidence-based medicine.

CONCLUSION

The results of this survey show that venous thromboembolism is regarded as a significant complication of orthopaedic surgery and most orthopaedic surgeons actively try to prevent it. There was a higher rate of intervention compared to previous surveys of Irish orthopaedic surgeons, possibly reflecting surgeon concerns regarding the high rate of litigation nationally. However, there is no consensus as to the optimum therapy which reflects the conflicting evidence available in the many publications on this subject.

Venous thromboembolism events in trauma patients after hospital discharge

BACKGROUND

Venous thromboembolism (VTE) is common after major injury. This elevated VTE risk likely continues beyond hospital discharge, but a lack of postdischarge surveillance limits our understanding of this complication and opportunities for improving outcomes. We aimed to characterize the incidence and risk factors of trauma patients who developed a VTE in the first year after discharge from their index hospital admission.

METHODS

We used data from adult inpatients (18 years or older) from 35 American College of Surgeons - Committee on Trauma-verified Level 1 and Level 2 trauma centers in a statewide trauma quality improvement program from 2018 to 2023. The incidence and timing of a postdischarge VTE were identified from linked longitudinal insurance claims data, and multivariable logistic regression was performed to identify predictors of a postdischarge event.

RESULTS

Of 34,421 trauma registry and claims matched patients identified, 1,487 (4.3%) developed a VTE within the first year after discharge from the trauma center, compared with 280 VTE events (0.8%) diagnosed during the index admission. The incidence of VTE remained elevated well after discharge, with 40% occurring in the first 30 days and 73% within the first 3 months. Multiple patient, injury, and treatment factors were associated with postdischarge VTE risk, including having an operation, a significant spine injury, Black race, and receiving a blood transfusion.

CONCLUSION

The risk of VTE extends well beyond the index hospitalization for trauma patients, as the majority of events occur after discharge. Understanding and improving VTE outcomes in trauma patients will require a longitudinal patient record that captures these complications. Postdischarge VTEs are an underrecognized trauma-related morbidity but are also very treatable through a better understanding of the risk factors and the optimal prophylactic strategy.

LEVEL OF EVIDENCE

Prognostic and Epidemiologic; Level III.

Predictors of Venous Thromboembolism Following Geriatric Distal Femur Fracture Fixation: Are These Patients at Higher Risk Compared With Hip Fracture Patients?

INTRODUCTION

Venous thromboembolism (VTE) following injury and subsequent fixation of a distal femur fracture (DFFx) is associated with considerable morbidity. However, the incidence of VTE, associated factors, and the relative risk compared with hip fracture (HFx) fixation remains poorly characterized.

METHODS

Retrospective cohort study using the PearlDiver M165 database to identify geriatric patients who underwent DFFx and HFx fixation. Clinical risk factors of VTE within 90 days of DFFx and the risk modification associated with enoxaparin (Lovenox) and direct oral anticoagulants (DOACs) relative to aspirin/nonprescription agents were characterized. To determine the odds of VTE following fixation of DFFx relative to HFx, a matched comparison based on age, sex, and Elixhauser Comorbidity Index was done.

RESULTS

Of 24,358 DFFx patients, 1684 (6.9%) developed VTE. Independent risk factors included a prior VTE (odds ratio [OR] 28.76), displaced DFFx morphologies (condylar [OR 5.44], and supracondylar without intracondylar extension [OR 3.96] and with extension [OR 3.75]), active cancer (OR 2.11), coagulopathy disorder (OR 1.15), and younger age (OR 1.03) (P < 0.05 for all). Lovenox and DOAC were both associated with reduced odds of VTE (OR 0.40 and OR 0.61, respectively) (P < 0.05 for both). Relative to HFx patients, DFFx patients demonstrated heightened odds of VTE (OR 1.25) (P < 0.001).

DISCUSSION

This study identified a relatively high rate of VTE, 6.9% within 90 days, following surgical management of DFFx and heightened odds of VTE relative to HFx patients. Various factors demonstrated a notable association with increased odds of VTE, although both Lovenox and DOACs may be effective therapeutic options for risk mitigation.

The effects of common peroneal nerve electrical stimulation on lower extremity deep venous hemodynamics: A randomized, crossover and controlled study

BACKGROUND

Intermittent pneumatic compression (IPC) and neuromuscular electrical stimulation can improve deep vein hemodynamics in the lower limbs. We developed a new, small and convenient, and easy to wear common peroneal nerve electrical stimulator (CPNES) and to investigate the effectiveness and safety of CPNES intervention on deep venous hemodynamics.

METHODS

Thirty healthy volunteers were recruited and randomly divided into group A and B. In group A, the hemodynamics of the left superficial femoral artery and the superficial femoral vein were measured after IPC compression, and then the CPNES was activated and the hemodynamics was measured again. In group B, the order of intervention was reversed.

RESULTS

In group A, the peak velocity, time average blood flow velocity (TAMV), and flow velocity of femoral vein after IPC and CPNES intervention were higher than these of the baseline (P < .05, respectively). No significant differences of these blood flow parameters were found between IPC and CPNES intervention (P > .05, respectively). In group B, these blood flow parameters of femoral vein after IPC and CPNES intervention were higher than these of the baseline (P < .05, respectively). No significant difference of these blood flow parameters (P > .05, respectively) were noted between IPC and CPNES intervention as well. No differential change of these flow velocity of femoral artery after IPC and CPNES intervention in group A or group B. The hemodynamics of superficial femoral arteries and veins after intervention in group A and B were similar (P > .05, respectively).

CONCLUSION

The effectiveness of CPNES intervention on the hemodynamics of the lower extremity is similar with that of IPC, increasing blood flow and may prevent venous thrombosis without adverse reaction.

Retrospective analysis of tranexamic acid administration in French war-wounded between October 2016 and September 2020

INTRODUCTION

Since 2013, the French Army Health Service, in agreement with international experts, has recommended the administration of 1 g of tranexamic acid (TXA) in trauma patients in haemorrhagic shock or at risk of bleeding within 3 hours of the trauma.

METHODS

The aim of this analysis was to describe the administration of TXA in French military personnel wounded during military operations in the Sahelo-Sahelian band between October 2016 and September 2020. Data were collected from forward health records and hospital data from the French hospital where the casualty was finally evacuated. Underuse of TXA was defined as the lack of administration in casualties who had received a blood transfusion with one or more of red blood cells, low-titre whole blood or French lyophilised plasma within the first 24 hours of injury and overuse as its administration in the non-transfused casualty.

RESULTS

Of the 76 patients included, 75 were men with an average age of 28 years. Five patients died during their management. 19 patients received TXA (25%) and 16 patients were transfused (21%). Underuse of TXA occurred in 3 of the 16 patients (18.8%) transfused. Overuse occurred in 6 of 60 (10%) non-transfused patients.

CONCLUSION

The analysis found an important underuse of TXA (almost 20%) and highlighted the need for optimising the prehospital clinical practice guidelines to aid prehospital medical practitioners more accurately in administering TXA to casualties that will require blood products.

Practice variation in venous thromboembolism prophylaxis in adolescent trauma patients: A comparative analysis of pediatric, adult, and mixed trauma centers

INTRODUCTION

Adolescent trauma patients are at increased risk of venous thromboembolism (VTE). It is unclear whether VTE prophylaxis practice patterns differ across trauma center types.

METHODS

The ACS-TQP database was queried for patients aged 12-17 admitted to a pediatric, adult, or mixed level I/II trauma center. VTE prophylaxis was compared between center types. Preplanned subgroup analyses were performed to evaluate guideline adherence.

RESULTS

Of 101,010 patients included, 35 ​% were treated at a pediatric trauma center (PTC), 43 ​% at a mixed trauma center (MTC), and 22 ​% at an adult trauma center (ATC). VTE prophylaxis was more common at ATCs and MTCs compared to PTCs (51.0 ​% vs 24.9 ​% vs 5.0 ​%,p ​< ​0.001). This trend persisted in subgroup analyses of patients aged 16-17 (63.8 ​% vs 40.5 ​% vs 6.4 ​%,p ​< ​0.001) and with injury severity score greater than 25 (83.8 ​% vs 74.0 ​% vs 35.1 ​%,p ​< ​0.001).

CONCLUSION

VTE prophylaxis is administered more frequently to adolescent trauma patients treated at ATCs and MTCs compared to PTCs despite published guidelines. Prospective studies are needed to assess the clinical utility of VTE prophylaxis in the adolescent trauma population.

Impact of an updated venous thromboembolism prophylaxis guideline in critically ill trauma patients on rates of venous thromboembolisms

INTRODUCTION

The objective of this analysis was to evaluate differences in incidence of venous thromboembolisms (VTE) in critically ill trauma patients between pre- and post-implementation of updated VTE prophylaxis guidelines.

METHODS

This was a pre-post analysis of critically ill trauma patients receiving pharmacologic VTE prophylaxis. Trauma patients were included if they had an intensive care unit admission during their hospitalization. The primary outcome was incidence of detected VTE and was analyzed using a Chi-Squared test. A multivariate analysis assessed the effects of guideline implementation on VTE development when controlling for confounders.

RESULTS

There were 220 patients included. There was a significant increase in low molecular weight heparin use in initial (p ​= ​0.003) and final (p ​= ​0.004) prophylactic regimens between groups. There was no significant difference in VTE incidence between the pre and post groups (6.3% vs 1.9%, p ​= ​0.10). The multivariate analysis showed guideline implementation was independently associated with an 88% reduced odds of VTE (p ​= ​0.04).

CONCLUSION

This analysis suggests the updated VTE prophylaxis guideline implementation was associated with a trend toward reduced VTE development among critically ill trauma patients.

TXA combined with whole blood transfusion in trauma patients does not increase the risk of VTE but shock index does

INTRODUCTION

Previous studies have demonstrated the benefits of tranexamic acid (TXA) administration in combination with packed red blood cell (PRBC) transfusion in trauma patients without increasing the risk of venous thromboembolism (VTE). However, the effect of TXA in combination with whole blood (WB) has not been studied. Injury, abbreviated injury severity scores (ISS and AIS) and the need for blood transfusions are historically associated with VTE. The objective of this study was to determine the relationship between VTE and the combination of TXA administration and transfusion of PRBCs vs. WB.

METHODS

Our institutional trauma registry was queried for trauma patients between 2015 and 2022 who received either WB ​+ ​TXA or PRBC ​+ ​TXA either prehospital or within 4 ​h of arrival. Multivariate analysis was utilized to determine independent risk factors for VTE, which were defined as either a deep vein thrombosis (DVT) or a pulmonary embolism (PE). Model covariates included age, mechanism of injury (MOI), ISS, lower extremity AIS, comorbid conditions, and shock index (SI). Additional outcomes analyzed were hospital length of stay (LOS), ICU LOS, and ventilator days.

RESULTS

Three hundred and five patients had complete data and were included in the analysis. Of those, 251 received WB ​+ ​TXA and 54 received PRBC ​+ ​TXA. A total of 34 patients were found to have VTE event (11.1 ​%); 28 (11.2 ​%) and 6 (11.1 ​%) from the WB ​+ ​TXA and PRBC ​+ ​TXA groups, respectively. An elevated pre-hospital SI was independently associated with increased VTE rate (OR 1.85, 95 ​% CI 1.07-3.20). WB transfusion, TXA administration, ISS, and MOI did not influence the rate of VTE.

CONCLUSION

These data demonstrate that the combination of WB ​+ ​TXA administered to trauma patients has no higher risk of VTE than patients who receive PRBC ​+ ​TXA, a comparison that has not been studied clinically to date. Despite the pro thrombotic state enhanced by TXA and the decreased dilutional coagulopathy seen in WB resuscitation, there was no increased risk of VTE compared to TXA ​+ ​PRBC. There is no evidence that TXA combined with whole blood transfusion is associated with an increased risk of VTE. However, higher pre-hospital SI was associated with an elevated rate of VTE. These clinical features provide insight into patients who may be at an increased risk of developing VTE and may benefit from targeted prevention strategies.

Does preperitoneal packing increase venous thromboembolim risk among trauma patients? A prospective multicenter analysis across 17 level I trauma centers

INTRODUCTION

Pelvic fractures are associated with a high risk of venous thromboembolism (VTE). Among treatment options, including pelvic angioembolization (PA), preperitoneal pelvic packing (PPP), and pelvic open reduction internal fixation (ORIF), PPP has been postulated as a VTE risk factor. We aimed to characterize the risk of VTE among pelvic fracture patients receiving PPP, PA or ORIF.

METHODS

We used observational data from a 17-site Consortium of Leaders in the Study of Traumatic Thromboembolism (CLOTT) study group, a US level I trauma center collaborative working to identify factors associated with posttraumatic VTE, deep venous thrombosis, pulmonary embolism, or pulmonary thrombosis. The CLOTT criteria included age 18 to 40 years with at least one independent VTE risk factor. We compared outcomes of PPP, PA, and pelvic ORIF to reference of no pelvic intervention. Our primary outcome was VTE. A competing risk analysis was performed.

RESULTS

Among 1,387 pelvic fracture patients, VTE incidence was 5.6%. The ORIF patients were most likely to develop VTE (24.7%), while VTE incidence for PPP was 9.0% and 2.6% for PA. After multivariate, risk-competing analysis, none of the three treatment interventions for pelvic fractures were significantly associated with VTE. Initiation of VTE prophylaxis in the first 24 hours of admission independently halved VTE incidence (hazard ratio, 0.55; confidence interval, 0.33-0.91).

CONCLUSION

Pelvic fracture interventions do not appear to be independent risk factors for VTE in our study. Initiation of VTE pharmacoprophylaxis within the first 24 hours of admission remains critical to significantly decreasing VTE formation in this high-risk population.

LEVEL OF EVIDENCE

Therapeutic Study; Level III.

Arterial Thrombosis in Acute Respiratory Infections: An Underestimated but Clinically Relevant Problem

During the COVID-19 pandemic, there was increased interest in the issue of thrombotic complications of acute respiratory infections. Clinical reports and pathological studies have revealed that thrombus formation in COVID-19 may involve the venous and arterial vasculature. As thrombotic complications of infectious respiratory diseases are increasingly considered in the context of COVID-19, the fact that thrombosis in lung diseases of viral and bacterial etiology was described long before the pandemic is overlooked. Pre-pandemic studies show that bacterial and viral respiratory infections are associated with an increased risk of thrombotic complications such as myocardial infarction, ischemic stroke, pulmonary embolism, and other critical illnesses caused by arterial and venous thrombosis. This narrative review article aims to summarize the current evidence regarding thrombotic complications and their pathogenesis in acute lower respiratory tract infections.

The Earlier the Better: Surgical Stabilization of Rib Fractures Associated With Improved Outcomes

INTRODUCTION

Surgical stabilization of rib fractures (SSRF) has been associated with lower rates of mortality and fewer respiratory complications. This study sought to evaluate the association between SSRF timing and patient outcomes.

METHODS

This retrospective analysis included patients aged ≥45 y who underwent SSRF in the Trauma Quality Improvement Program database from 2016 to 2020. Primary outcome was incidence of ventilator-assisted pneumonia (VAP). Secondary outcomes included acute respiratory distress syndrome (ARDS), unplanned endotracheal intubation, in-hospital mortality, failure to rescue (FTR) after all major complications, and FTR after severe respiratory complications. Logistic regression models of outcomes on timing to SSRF were fit while controlling for age, gender, body mass index, injury severity score, flail chest, chronic obstructive pulmonary disease, congestive heart failure, and smoking.

RESULTS

Among 4667 patients who received SSRF, average time to SSRF was 4.6 ± 3.2 d. Each additional day to SSRF was associated with increased odds of VAP (odds ratio [OR] 1.07, confidence interval [CI] 1.03-1.11) and intubation (OR 1.10, CI 1.08-1.13). A longer time to SSRF was associated with increased odds of ARDS (OR 1.10, CI 1.05-1.15), while no significant association was observed for in-hospital mortality (OR 0.99, CI 0.93-1.04). A longer time to SSRF was associated with decreased odds of FTR after a major complication (OR 0.90, CI 0.83-0.97) and respiratory complications (OR 0.87, CI 0.78-0.96).

CONCLUSIONS

For each day that SSRF is delayed, increased odds of VAP, intubation, and ARDS were observed. Prompt intervention is crucial for preventing these complications and improving our ability to rescue patients.

Optimal Timing for Initiation of Thromboprophylaxis After Hepatic Angioembolization

OBJECTIVE

To evaluate the optimal timing of thromboprophylaxis (TPX) initiation after hepatic angioembolization in trauma patients.

BACKGROUND

TPX after hepatic trauma is complicated by the risk of bleeding, but the relative risk after hepatic angioembolization is unknown.

METHODS

Patients who underwent hepatic angioembolization within 24 hours were retrospectively identified from the 2017 to 2019 American College of Surgeons Trauma Quality Improvement Project data sets. Cases with <24-hour length of stay and other serious injuries were excluded. Venous thromboembolism (VTE) included deep venous thrombosis and PE. Bleeding complications included hepatic surgery, additional angioembolization, or blood transfusion after TPX initiation. Differences were tested with univariate and multivariate analyses.

RESULTS

Of 1550 patients, 1370 had initial angioembolization. Bleeding complications were higher in those with TPX initiation within 24 hours (20.0% vs 8.9%, P <0.001) and 48 hours (13.2% vs 8.4%, P =0.013). However, VTE was higher in those with TPX initiation after 48 hours (6.3% vs 3.3%, P =0.025). In the 180 patients with hepatic surgery before angioembolization, bleeding complications were higher in those with TPX initiation within 24 hours (72% vs 20%, P <0.001), 48 hours (50% vs 17%, P <0.001), and 72 hours (37% vs 14%, P =0.001). Moreover, deep venous thrombosis was higher in those with TPX initiation after 96 hours (14.3% vs 3.1%, P =0.023).

CONCLUSIONS

This is the first study to address the timing of TPX after hepatic angioembolization in a national sample of trauma patients. For these patients, initiation of TPX at 48 to 72 hours achieves the safest balance in minimizing bleeding while reducing the risk of VTE.

LEVEL OF EVIDENCE

Level III-retrospective cohort study.

Prognostic factors associated with venous thromboembolism following traumatic injury: A systematic review and meta-analysis

INTRODUCTION

Trauma patients are at increased risk of venous thromboembolism (VTE), including deep venous thrombosis and/or pulmonary embolism. We conducted a systematic review and meta-analysis summarizing the association between prognostic factors and the occurrence of VTE following traumatic injury.

METHODS

We searched the Embase and Medline databases from inception to August 2023. We identified studies reporting confounding adjusted associations between patient, injury, or postinjury care factors and risk of VTE. We performed meta-analyses of odds ratios using the random-effects method and assessed individual study risk of bias using the Quality in Prognosis Studies tool.

RESULTS

We included 31 studies involving 1,981,946 patients. Studies were predominantly observational cohorts from North America. Factors with moderate or higher certainty of association with increased risk of VTE include older age, obesity, male sex, higher Injury Severity Score, pelvic injury, lower extremity injury, spinal injury, delayed VTE prophylaxis, need for surgery, and tranexamic acid use. After accounting for other important contributing prognostic variables, a delay in the delivery of appropriate pharmacologic prophylaxis for as little as 24 to 48 hours independently confers a clinically meaningful twofold increase in incidence of VTE.

CONCLUSION

These findings highlight the contribution of patient predisposition, the importance of injury pattern, and the impact of potentially modifiable postinjury care on risk of VTE after traumatic injury. These factors should be incorporated into a risk stratification framework to individualize VTE risk assessment and support clinical and academic efforts to reduce thromboembolic events among trauma patients.

LEVEL OF EVIDENCE

Systematic Review and Meta-Analysis; Level III.

Evaluating chemical venous thromboembolism prophylaxis in trauma patients at a single Australian center

PURPOSE

Trauma patients are at an elevated risk of developing venous thromboembolism (VTE), with the subsequent mortality in patients requiring intensive care unit admission ranging from 25% to 38%. There remains significant variability in clinical practice related to VTE prophylaxis in trauma patients due to the frequent presence of contraindications impacting the timing and consistency of application. This study aimed to assess the effectiveness of the current practice of chemical VTE prophylaxis in trauma patients at a single Australian center.

METHODS

A prospective review was conducted on patients admitted to the ACT Trauma Service (Canberra, Australia) from July to November 2022. The included patients were 18 years or older, without a direct contraindication to anticoagulation, who received chemical VTE prophylaxis with low-molecular-weight heparin (enoxaparin) for at least three doses and underwent subsequent testing of anti-factor Xa (aFXa) levels.

RESULTS

During the study period, 187 patients were admitted, of whom 63 were included in the study. Of these, 47 patients achieved therapeutic levels of anticoagulation as determined by their aFXa levels, while 16 were subtherapeutic. The only statistically significant difference between the two groups was in weight, with patients in the subtherapeutic group weighing an average of 91.9 kg compared to 79.1 kg in the therapeutic group (P<0.05).

CONCLUSIONS

A fixed-dose enoxaparin regimen was utilized, with limited individualization based on patient factors, such as injuries, comorbidities, and other biological factors. Sixteen patients (25%) had subtherapeutic VTE prophylaxis, as measured by aFXa levels. Higher weight was significantly correlated with inadequate VTE prophylaxis dosing. While age, sex, and smoking status might play important roles in clinical decision-making, weight-based dosing of low-molecular-weight heparin may be more effective in achieving adequate VTE prophylaxis.

Post-discharge 6-Month Functional Recovery of Traumatic Brain Injury Survivors with Unfavorable Functional Status at Discharge: A Registry-Based Cohort Study

BACKGROUND

Traumatic brain injury (TBI) is a major cause of physical disabilities worldwide. Herein, we aimed to investigate the factors contributing to post-discharge recovery in patients who were discharged with an unfavorable outcome.

METHODS

We collected data on the characteristics of patients, with a focus on those who survived TBI but had an unfavorable outcome at discharge as measured by Glasgow Outcome Scale Extended (GOSE) categories 2, 3, and 4. Post-discharge recovery was defined as achieving a favorable functional status at 6 months (GOSE of 5 or more) with a minimum 2-point increase in GOSE.

RESULTS

Of 4011 TBI patients in our registry, 797 had an unfavorable discharge functional status. In severe TBI, 51% achieved recovery, while in mild to moderate TBI, 57% achieved recovery after 6 months. Older patients and those with shorter intensive care unit length of stay were more likely to experience post-discharge recovery in both mild to moderate and severe TBI groups. The presence of skull base fracture was also associated with post-discharge recovery in severe TBI patients. Lastly, we show that, after adjustment for potential confounders, GOSE at discharge is associated with post-discharge recovery in both mild to moderate and severe TBI patients.

CONCLUSIONS

This study found that the majority of patients discharged with an unfavorable functional status were able to achieve a favorable outcome within 6 months. The novel post-discharge recovery in TBI patients might be a useful tool for illuminating the factors associated with a significant improvement after discharge.

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.

A 20-year retrospective analysis of deep venous thrombosis and pulmonary embolism among combat casualties requiring damage-control laparotomy at US military Role 2 surgical units

BACKGROUND

Combat casualties receiving damage-control laparotomy at forward deployed, resource-constrained US military Role 2 (R2) surgical units require multiple evacuations, but the added risk of venous thromboembolism (VTE) in this population has not been defined. To fill this gap, we retrospectively analyzed 20 years of Department of Defense Trauma Registry data to define the VTE rate in this population.

METHODS

Department of Defense Trauma Registry from 2002 to 2023 was queried for US military combat casualties requiring damage-control laparotomy at R2. All deaths were excluded in subsequent analysis. Rates of VTE were assessed, and subgroup analysis was performed on patients requiring massive transfusion.

RESULTS

Department of Defense Trauma Registry (n = 288) patients were young (mean age, 25 years) and predominantly male (98%) with severe (mean Injury Severity Score, 26), mostly penetrating injury (76%) and high mortality. Venous thromboembolism rate was high: 15.8% (DVT, 10.3%; pulmonary embolism, 7.1%). In the massively transfused population, the VTE rate was even higher (26.7% vs. 10.2%, p < 0.001).

CONCLUSION

This is the first report that combat casualties requiring damage-control laparotomy at R2 have such high VTE rates. Therefore, for military casualties, we propose screening ultrasound upon arrival to each subsequent capable echelon of care and low threshold for initiating thromboprophylaxis.

LEVEL OF EVIDENCE

Prognostic and Epidemiological; Level IV.

Venous Thromboembolic Events in Adult Trauma Patients Receiving Balanced Hemostatic Resuscitation (BHR): An Analysis of Their Incidence, Predictors, and Associated Mortality Rates at a Level 1 Trauma Center

Background and objective Studies assessing the incidence of venous thromboembolic (VTE) events in the setting of massive balanced transfusions and/or tranexamic acid (TXA) infusion have yielded varied outcomes. In light of this, we conducted this study to examine the incidence of VTEs in trauma patients requiring blood products, and to identify the risk factors for VTE and mortality in this population. Methods We performed a retrospective analysis of trauma patients admitted to our level 1 trauma center from January 2013 to September 2023. Clinical characteristics were compared between patients who developed VTE and those who did not. A regression analysis of potential variables associated with the development of VTEs and mortality was performed. Results Among 1305 patients (mean age: 42.4 ± 18.8 years) receiving blood products within the initial 24 hours, 4.3% (56 patients) developed a VTE. Patients with VTE experienced prolonged ICU and hospital stays and ventilation duration (p<0.001). They were also noted to have delayed initiation of VTE prophylaxis (104.2 vs. 50.3 hours, p<.001). Prolonged ventilation >7 days was the sole significant factor associated with VTE in multivariate regression analysis [odds ratio (OR): 6.2, p=0.004]. Early TXA administration (within four hours) showed a higher association with VTE than TXA within 24 hours (OR: 2.1, p=0.07 vs. OR 1.6, p=0.22). Massive transfusion was found to increase VTE risk (OR: 2.65, p<0.001). Severe head and neck (OR: 6.0, p=0.002) and chest (OR: 3.8, p=0.01) injuries were key predictors of mortality, while TXA was not significantly associated with mortality in the multivariate model. Conclusions Our study revealed an elevated risk of VTE in patients requiring massive transfusion protocol (MTP, ≥6 units). Early TXA administration was neither associated with increased VTE risk in MTP patients nor increased mortality risk. Strategies directed at reducing the risk of VTE in massively transfused patients while maintaining the survival benefits of balanced resuscitation and TXA need to be devised.

When is it safe to start thromboprophylaxis after splenic angioembolization?

BACKGROUND

Thromboprophylaxis after blunt splenic trauma is complicated by the risk of bleeding, but the risk after angioembolization is unknown. We hypothesized that earlier thromboprophylaxis initiation was associated with increased bleeding complications without mitigating venous thromboembolism events.

METHODS

All blunt trauma patients who underwent splenic angioembolization within 24 hours of arrival were identified from the American College of Surgeons Trauma Quality Improvement Program datasets from 2017 to 2019. Cases with <24-hour length of stay, other serious injuries, and surgery before angioembolization were excluded. Venous thromboembolism was defined as deep vein thrombosis or pulmonary embolism. Bleeding complications were defined as splenic surgery, additional embolization, or blood transfusion after thromboprophylaxis initiation. Data were compared with χ2 analysis and multivariate logistic regression at P < .05.

RESULTS

In 1,102 patients, 84% had American Association for the Surgery of Trauma grade III to V splenic injuries, and 73% received thromboprophylaxis. Splenic surgery after angioembolization was more common in those with thromboprophylaxis initiation within the first 24 hours (5.7% vs 1.7%, P = .007), whereas those with the initiation of thromboprophylaxis after 72 hours were more likely to have a pulmonary embolism (2.3% vs 0.2%, P = .001). Overall, venous thromboembolism increased considerably when thromboprophylaxis was initiated after day 3. In multivariate analysis, time to thromboprophylaxis initiation was associated with bleeding (odds ratio 0.74 [95% confidence interval 0.58-0.94]) and venous thromboembolism complications (odds ratio 1.5 [95% confidence interval 1.20-1.81]).

CONCLUSION

This national study evaluates bleeding and thromboembolic risk to elucidate the specific timing of thromboprophylaxis after splenic angioembolization. Initiation of thromboprophylaxis between 24 and 72 hours achieves the safest balance in minimizing bleeding and venous thromboembolism risk, with 48 hours particularly serving as the ideal time for protocolized administration.

Incidence and influence factors of venous thromboembolism in traumatic rib fracture patient: a multicenter study

BACKGROUND

This study aimed to determine the incidence and influencing factors of venous thromboembolism (VTE) in patients with traumatic rib fractures.

METHODS

The retrospective study analyzed medical records of patients with traumatic rib fractures from 33 hospitals.

RESULTS

The overall incidence of VTE in hospitalized patients with traumatic rib fractures was 8.1%. Patients with isolated traumatic rib fractures had a significantly lower incidence of VTE (4.4%) compared to patients with rib fractures combined with other injuries (12.0%). Multivariate analysis identified the number of rib fractures as an independent risk factor for thrombosis. Surgical stabilization of isolated rib fractures involving three or more ribs was associated with a lower VTE incidence compared to conservative treatment.

CONCLUSIONS

Patients with rib fractures have a higher incidence of VTE, positively correlated with the number of rib fractures. However, the occurrence of thrombosis is relatively low in isolated rib fractures. Targeted thromboprophylaxis strategies should be implemented for these patients, and surgical stabilization of rib fractures may be beneficial in reducing the risk of VTE.

Inadequate prophylaxis in patients with trauma: anti-Xa-guided enoxaparin dosing management in critically ill patients with trauma

Venous thromboembolism (VTE) causes significant morbidity in patients with trauma despite advances in pharmacologic therapy. Prior literature suggests standard enoxaparin dosing may not achieve target prophylactic anti-Xa levels. We hypothesize that a new weight-based enoxaparin protocol with anti-Xa monitoring for dose titration in critically injured patients is safe and easily implemented.

Methods

This prospective observational study included patients with trauma admitted to the trauma intensive care unit (ICU) from January 2021 to September 2022. Enoxaparin dosing was adjusted based on anti-Xa levels as standard of care via a performance improvement initiative. The primary outcome was the proportion of subtarget anti-Xa levels (<0.2 IU/mL) on 30 mg two times per day dosing of enoxaparin. Secondary outcomes included the dosing modifications to attain goal anti-Xa levels, VTE and bleeding events, and hospital and ICU lengths of stay.

Results

A total of 282 consecutive patients were included. Baseline demographics revealed a median age of 36 (26-55) years, and 44.7% with penetrating injuries. Of these, 119 (42.7%) achieved a target anti-Xa level on a starting dose of 30 mg two times per day. Dose modifications for subtarget anti-Xa levels were required in 163 patients (57.8%). Of those, 120 underwent at least one dose modification, which resulted in 78 patients (47.8%) who achieved a target level prior to hospital discharge on a higher dose of enoxaparin. Overall, only 69.1% of patients achieved goal anti-Xa level prior to hospital discharge. VTE occurred in 25 patients (8.8%) and major bleeding in 3 (1.1%) patients.

Conclusion

A majority of critically injured patients do not meet target anti-Xa levels with 30 mg two times per day enoxaparin dosing. This study highlights the need for anti-Xa-based dose modification and efficacy of a pharmacy-driven protocol. Further optimization is warranted to mitigate VTE events.

Level of evidence

Therapeutic/care management, level III.

Venous thromboembolism chemoprophylaxis in geriatric trauma patients with isolated severe traumatic brain injury

PURPOSE

Low-molecular-weight-heparin (LMWH) has been shown to be associated with a decreased risk of venous thromboembolism (VTE) and mortality compared to unfractionated heparin (UH) in severe traumatic brain injury (TBI). The aim of this study was to see if this association persists among a subset of patients, namely elderly patients with isolated TBI.

METHODS

This Trauma Quality Improvement Project (TQIP) database study included patients ≥ 65 years old with severe TBI (Abbreviated injury score [AIS] ≥ 3) that received either LMWH or UH for VTE prophylaxis. Patients with associated severe injuries (extracranial AIS ≥ 3), transferals, deaths < 72-h, hospitalization < 2 days, VTE chemoprophylaxis other than UH or LMWH, or with a history of bleeding diathesis were excluded. The association between VTE, deep vein thrombosis (DVT), and pulmonary embolism (PE) with VTE chemoprophylaxis was analyzed with multivariable analysis, subset analyses of different grades of AIS-head injury, and a 1:1 matched LWMH:UH cohort of patients.

RESULTS

Out of 14,926 patients, 11,036 (73.9%) received LMWH. Multivariate analysis showed that patients receiving LMWH had a decreased risk of mortality (OR 0.81, 95% CI 0.67-0.97, p < 0.001) but a similar risk of VTE (OR 0.83, 95% CI 0.63-1.08). Analysis according to head-AIS showed that LMWH was associated with a decreased risk of PE in patients AIS-3 but not in AIS 4 or 5. In a 1:1 matched cohort of LMWH:UH patients, the risk of PE, DVT and VTE were all similar but LMWH continued to be associated with a decreased risk of mortality (OR 0.81, CI 0.67-0.97, p = 0.023).

CONCLUSION

LMWH was associated with a decreased risk of overall mortality and reduced risk of PE compared to UH among geriatric patients with a severe head injury.

Post-discharge venous thromboembolism prophylaxis in hospitalized trauma patients: A retrospective comparison of patients receiving versus not receiving post-discharge prophylaxis

BACKGROUND

Risk of venous thromboembolism (VTE) in many trauma patients extends beyond hospitalization, but there is a paucity of evidence to guide the use of post-discharge prophylaxis (PDP).

METHODS

A retrospective cohort study of trauma patients deemed moderate-to-high risk for VTE (risk assessment profile score [RAP] ≥5) who were prescribed PDP based on an internal clinical guideline assessing injury pattern and mobility status. PDP patients were compared with those that did not receive post-discharge prophylaxis (NPDP).

RESULTS

1512 patients were included. PDP group had higher mean RAP score (7.3 vs. 6.4, p ​< ​0.001), more likely to have a complex orthopedic fracture and underwent a longer median hospital (4.7 vs. 2.9 days, p ​< ​0.001). No difference between groups in 90-day VTE (11 [1.5 ​%] (PDP) vs. 8 [1.0 ​%] (NPDP), p ​= ​0.50), clinically relevant bleeding (p ​= ​0.58), or readmission (p ​= ​0.46).

CONCLUSIONS

VTE incidence, clinically relevant bleeding, and readmission 90-days after hospital discharge were low and similar between PDP and NPDP groups. PDP prescribed in a presumably higher VTE risk trauma population may mitigate the long-term risk of VTE.

Comparative study of two models predicting the risk of deep vein thrombosis progression in spinal trauma patients after operation

OBJECTIVE

Patients with preoperative deep vein thrombosis (DVT) exhibit a notable incidence of postoperative deep vein thrombosis progression (DVTp), which bears a potential for silent, severe consequences. Consequently, the development of a predictive model for the risk of postoperative DVTp among spinal trauma patients is important.

METHODS

Data of 161 spinal traumatic patients with preoperative DVT, who underwent spine surgery after admission, were collected from our hospital between January 2016 and December 2022. The least absolute shrinkage and selection operator (LASSO) combined with multivariable logistic regression analysis was applied to select variables for the development of the predictive logistic regression models. One logistic regression model was formulated simply with the Caprini risk score (Model A), while the other model incorporated not only the previously screened variables but also the age variable (Model B). The model's capability was evaluated using sensitivity, specificity, positive predictive value, negative predictive value, accuracy, F1 score, and receiver operating characteristic (ROC) curve. Nomograms simplified and visually presented Model B for the clinicians and patients to understand the predictive model. The decision curve was used to analyze the clinical value of Model B.

RESULTS

A total of 161 DVT patients were enrolled in this study. Postoperative DVTp occurred in 48 spinal trauma patients, accounting for 29.81% of the total patient enrolled. Model A inadequately predicted postoperative DVTp in spinal trauma patients, with ROC AUC values of 0.595 for the training dataset and 0.593 for the test dataset. Through the application of LASSO regression and multivariable logistic regression, a screening process was conducted for seven risk factors: D-dimer, blood platelet, hyperlipidemia, blood group, preoperative anticoagulant, spinal cord injury, lower extremity varicosities. Model B demonstrated superior and consistent predictive performance, with ROC AUC values of 0.809 for the training dataset and 0.773 for the test dataset. According to the calibration curves and decision curve analysis, Model B could accurately predict the probability of postoperative DVTp after spine surgery. The nomograms enhanced the interpretability of Model B in charts and graphs.

CONCLUSIONS

In summary, we established a logistic regression model for the accurate predicting of postoperative deep vein thrombosis progression in spinal trauma patients, utilizing D-dimer, blood platelet, hyperlipidemia, blood group, preoperative anticoagulant, spinal cord injury, lower extremity varicosities, and age as predictive factors. The proposed model outperformed a logistic regression model based simply on CRS. The proposed model has the potential to aid frontline clinicians and patients in identifying and intervening in postoperative DVTp among traumatic patients undergoing spinal surgery.

Risk assessment scales to predict risk of lower extremity deep vein thrombosis among multiple trauma patients: a prospective cohort study

BACKGROUND

Deep vein thrombosis (DVT) is a common complication in orthopedic patients. Previous studies have focused on major orthopedic surgery.There are few studies with multiple trauma. We aimed to describe the prevalence of DVT and compare the predictive power of the different risk assessment scales in patients with multiple trauma.

METHODS

This prospective cohort study involved multiple trauma patients admitted to our hospital between October 2021 and December 2022. Data were prospectively collected for thrombotic risk assessments using the Risk Assessment Profile for thromboembolism(RAPT), the DVT risk assessment score (DRAS), and the Trauma Embolic Scoring System (TESS), respectively. The receiver operation characteristic (ROC) curve and the area under the curve (AUC) were evaluated to compare the predictive power. The whole leg duplex ultrasound of both lower extremities Doppler ultrasound was used to determine DVT incidence.

RESULTS

A total of 210 patients were included, and the incidence of DVT was 26.19%. Distal DVT accounted for 87.27%; postoperative DVT, 72.73%; and bilateral lower extremity thrombosis, 30.91%. There were significant differences in age, education degree, pelvic fracture, surgery, ISS, D-dimer level, length of hospital stay and ICU stay between the thrombosis group and the non-thrombosis group. The AUCs for RAPT, DRAS, and TESS were 0.737, 0.710, and 0.683, respectively. There were no significant differences between the three ROC curves.

CONCLUSIONS

The incidence of DVT was relatively high during hospitalization. We prospectively validated the tests to predict risk of DVT among patients with multiple trauma to help trauma surgeons in the clinical administration of DVT prophylaxis.

Low Molecular Weight Heparin Is Superior for Venous Thromboembolism Prophylaxis in High-Risk Geriatric Patients

INTRODUCTION

Venous thromboembolism (VTE) is a source of preventable morbidity and mortality in critically ill trauma patients. Age is one independent risk factor. Geriatric patients embody a population at high thromboembolic and hemorrhagic risk. Currently, there is little guidance between low molecular weight heparin (LMWH) and unfractionated heparin (UFH) for anticoagulant prophylaxis in the geriatric trauma patient.

METHODS

A retrospective review was conducted at an ACS verified, Level I Trauma center from 2014 to 2018. All patients 65 years or older, with high-risk injuries and admitted to the trauma service were included. Choice of agent was at provider discretion. Patients in renal failure, or those that received no chemoprophylaxis, were excluded. The primary outcomes were the diagnosis of deep vein thrombosis or pulmonary embolism and bleeding associated complications (gastrointestinal bleed, TBI expansion, hematoma development).

RESULTS

This study evaluated 375 subjects, 245 (65%) received enoxaparin and 130 (35%) received heparin. DVT developed in 6.9% of UFH patients, compared to 3.3% with LMWH (P = .1). PE was present in 3.8% of UFH group, but only .4% in the LMWH group (P = .01). Combined rate of DVT/PE was significantly lower (P = .006) with LMWH (3.7%) compared to UFH (10.8%). 10 patients had documented bleeding events, and there was no significant association between bleeding and the use of LMWH or UFH.

CONCLUSIONS

VTE events are more common in geriatric patients treated with UFH compared to LMWH. There was no associated increase in bleeding complications when LMWH was utilized. LMWH should be considered the chemoprophylatic agent of choice in high risk geriatric trauma patients.

Combination of aspirin and rosuvastatin for reduction of venous thromboembolism in severely injured patients: a double-blind, placebo-controlled, pragmatic randomized phase II clinical trial (The STAT Trial)

INTRODUCTION

Venous thromboembolism (VTE) remains a significant source of postinjury morbidity and mortality. Beta-hydroxy beta-methylglutaryl-CoA (HMG-CoA) reductase inhibitors (rosuvastatin) significantly reduced pathologic clotting events in healthy populations in a prior trial. Furthermore, acetylsalicylic acid (ASA) has been shown to be noninferior to prophylactic heparinoids for VTE prevention following orthopedic surgery. We hypothesized that a combination of rosuvastatin/ASA, in addition to standard VTE chemoprophylaxis, would reduce VTE in critically ill trauma patients.

METHODS

This was a double-blind, placebo-controlled, randomized trial, evaluating VTE rates in two groups: ASA + statin (Experimental) and identical placebos (Control). Injured adults, 18-65 years old, admitted to the surgical intensive care unit without contraindications for VTE prophylaxis were eligible. Upon initiation of routine VTE chemoprophylaxis (i.e. heparin/heparin-derivatives), they were randomized to the Experimental or Control group. VTE was the primary outcome.

RESULTS

Of 112 potentially eligible patients, 33% (n = 37, median new injury severity scale = 27) were successfully randomized, of whom 11% had VTEs. The Experimental group had no VTEs, while the Control group had 6 VTEs (4 PEs and 2 DVTs) in 4 (22%) patients (P = 0.046). The Experimental treatment was not associated with any serious adverse events. Due to the COVID-19 pandemic, the study was interrupted at the second interim analysis at <10% of the planned enrollment, with significance declared at P < 0.012 at that stage.

DISCUSSION

The combination of ASA and rosuvastatin with standard VTE prophylaxis showed a favorable trend toward reducing VTEs with no serious adverse events. An appropriately powered phase III multicenter trial is needed to further investigate this therapeutic approach.

LEVEL OF EVIDENCE

Level II, Therapeutic.

Venous thromboembolic disease in admitted blunt trauma patients: what matters?

BACKGROUND

Venous thromboembolic events (VTE) are a significant cause of morbidity and mortality following traumatic injury. We examined demographic characteristics, chemoprophylaxis, and outcomes of VTE patients with blunt trauma requiring hospitalization.

METHODS

A retrospective review of adult blunt trauma hospitalizations with and without VTE between 2012 and 2019 was conducted. Deaths in the emergency department were excluded. Univariate and multivariable analyses, including machine learning classification algorithms for VTE, were performed.

RESULTS

Of 10,926 admitted adult blunt trauma patients, 177 had VTE events. VTE events occurred at a median of 6 [IQR 3-11] days, with 7.3% occurring within 1 day of admission. VTE patients were more often male, and more often underwent surgery. They had higher injury severity as well as longer intensive care unit and hospital lengths of stay. While VTE occurred throughout the spectrum of injury severity, 27.7% had low injury severity (ISS < = 9). In multivariable analyses, both heparin and enoxaparin had reduced adjusted odds ratios for VTE.

CONCLUSION

Approximately 7.3% of VTE events occurred within one day of admission. A substantial proportion of VTE events occurred in patients with low injury severity (ISS < = 9). Subcutaneous unfractionated heparin and enoxaparin chemoprophylaxis were both inversely associated with VTE. These findings underscore the need for vigilance for VTE identification in blunt trauma patients throughout their hospitalization and VTE prevention efforts.

Low-molecular-weight heparin is superior to unfractionated heparin in lowering the risk of venous thromboembolism after traumatic lower extremity amputation

BACKGROUND

Patients undergoing lower extremity amputation after trauma are at high risk of venous thromboembolism. Practice variations persist regarding the optimal pharmacologic agent for venous thromboembolism prophylaxis in this patient population. We aimed to compare the efficacy of unfractionated heparin versus low-molecular-weight heparin in preventing venous thromboembolism.

METHODS

Using the 2013 to 2019 American College of Surgeons Pediatric Trauma Quality Improvement Program database, all trauma patients (≥18) who underwent lower limb amputation and received venous thromboembolism thromboprophylaxis in the form of unfractionated heparin or low-molecular-weight heparin were included. We excluded patients who died within 24 hours of admission or those who received no thromboprophylaxis. The primary outcome was the rate of venous thromboembolism. Multivariable logistic regression was used to evaluate the independent relationship between the type of pharmacologic prophylaxis and the risk of venous thromboembolism.

RESULTS

A total of 4,103 patients who underwent lower extremity amputation were identified. Patients were primarily young (median age 43 years) with blunt injuries (83%). The overall rate of venous thromboembolism was 8.6%. Most (77%) patients received low-molecular-weight heparin-based prophylaxis. Compared with patients without venous thromboembolism, the venous thromboembolism cohort had a greater injury severity score (19 vs 13, P < .001), had more patients undergoing above-the-knee amputation (48% vs 36%, P < .001), and less frequently received low-molecular-weight heparin (64% vs 78%, P < .001). Multivariable analysis showed that low-molecular-weight heparin was associated with a significantly lower venous thromboembolism rate than unfractionated heparin (odds ratio: 0.65 [0.51-0.83], P < .001).

CONCLUSION

Thromboprophylaxis with low-molecular-weight heparin was found to be superior to unfractionated heparin in lowering the risk of venous thromboembolism among traumatic amputees and should be the preferred pharmacologic agent in this patient population prone to venous thromboembolism.

Spectrum of Thrombotic Complications in Fatal Cases of COVID-19: Focus on Pulmonary Artery Thrombosis In Situ

COVID-19-related thrombosis affects the venous and arterial systems. Data from 156 autopsies of COVID-19 patients were retrospectively analyzed to investigate the pattern of thrombotic complications and factors associated with pulmonary artery thrombosis and thromboembolism. Thrombotic complications were observed in a significant proportion (n = 68, 44%), with pulmonary artery thrombosis the most frequently identified thrombotic event (42, 27%). Multivariate analysis revealed that the length of hospital stay (OR 1.1, p = 0.004), neutrophil infiltration in the alveolar spaces (OR 3.6, p = 0.002), and the absence of hyaline membranes (OR 0.1, p = 0.01) were associated with thrombotic complications. Neutrophil infiltration in the alveolar spaces (OR 8, p < 0.001) and the absence of hyaline membranes (OR 0.1, p = 0.003) were also independent predictors of pulmonary artery thrombosis. The association of pulmonary artery thrombosis with an absence of hyaline membranes suggests it occurs later in the course of COVID-19 infection. As neutrophil infiltration in the alveolar spaces may indicate bacterial infection, our studies suggest the consideration of bacterial infections in these critically ill patients.

Low-Dose Heparin Infusion as Venous Thromboembolism Chemoprophylaxis in Patients With Blunt Cerebrovascular Injury

INTRODUCTION

Blunt cerebrovascular injury (BCVI) can result in devastating stroke. Because of operative inaccessibility, the most common treatment for BCVI is aspirin or a low-dose systemic heparin infusion. While it is assumed that low dose heparin infusion imparts venous thromboembolism (VTE) prophylaxis, this has not been evaluated in the BCVI population. The purpose of this study was to evaluate VTE rates in patients receiving low-dose heparin infusion as treatment for BCVI.

METHODS

Patients diagnosed with BCVI between 2014 and 2018 were reviewed for initiation of low-dose systemic heparin treatment. VTE was defined as a deep vein thrombosis or pulmonary embolism. BCVI patients without systemic heparin treatment were compared to BCVI patients with heparin treatment for overall VTE rates. Comparisons were also made to injured patients without a BCVI in our Trauma Activation Protocol (TAP) database.

RESULTS

During the 5-year study period, 265 patients were identified with a BCVI. The majority (61%) were men with a median injury severity score (ISS) 22 (interquartile range [IQR]:14-33). Of these patients, 146 (55.1%) received a heparin infusion to treat BCVI. VTE was identified in eight of these patients (5.5%). Compared to TAP patients (n = 1020) who received standard dosing of VTE chemoprophylaxis, there was no difference in VTE rates compared to BCVI patients who were started on a low dose heparin infusion (3% versus 5.5%, P = 0.16). Area under the receiver operating characteristics (AUROC) was used to evaluate the predictive power of time to initiation of heparin infusion (AUC = 0.64 95% CI 0.42-0.85, P = 0.2) and time to reaching PTT goal (AUC = 0.52 95% CI 0.27-0.77, P = 0.83) as a predictor VTE events.

CONCLUSIONS

Low dose heparin infusion is frequently used as an initial treatment of BCVI. In injured patients with BCVI, a low dose heparin infusion is associated with a low rate of VTE, comparable to injured patients without BCVI that received standard VTE chemoprophylaxis.

Incidence and risk factors of deep vein thrombosis in patients with spinal cord injury: a systematic review with meta-analysis

Background

Spinal cord injury (SCI) is a highly disabling disease with huge public health burden. The complications associated with it, especially deep vein thrombosis (DVT), further aggravate the disability.

Objective

To explore the incidence and risk factors of DVT after SCI, in order to provide guidance for disease prevention in the future.

Methods

A search was performed on PubMed, Web of Science, Embase, and Cochrane database up to November 9, 2022. Literature screening, information extraction and quality evaluation were performed by two researchers. The data was later combined by metaprop and metan commands in STATA 16.0.

Results

A total of 101 articles were included, including 223,221 patients. Meta-analysis showed that the overall incidence of DVT was 9.3% (95% CI: 8.2%-10.6%), and the incidence of DVT in patients with acute and chronic SCI was 10.9% (95% CI: 8.7%-13.2%) and 5.3% (95% CI: 2.2%-9.7%), respectively. The incidence of DVT decreased gradually with the accumulation of publication years and sample size. However, the annual incidence of DVT has increased since 2017. There are 24 kinds of risk factors that may contribute to the formation of DVT, involving multiple aspects of the baseline characteristics of the patient, biochemical indicators, severity of SCI, and comorbidities.

Conclusions

The incidence of DVT after SCI is high and has been gradually increasing in recent years. Moreover, there are numerous risk factors associated with DVT. Comprehensive preventive measures need to be taken as early as possible in the future.

Systematic Review Registration

www.crd.york.ac.uk/prospero, identifier CRD42022377466.

Efficacy and Safety of Anti-Xa-Guided Versus Fixed Dosing of Low Molecular Weight Heparin for Prevention of Venous Thromboembolism in Trauma Patients: A Systematic Review and Meta-Analysis

PURPOSE

Trauma patients are at high risk of venous thromboembolism (VTE). We summarize the comparative efficacy and safety of anti-Xa-guided versus fixed dosing for low molecular weight heparin (LMWH) for the prevention of VTE in adult trauma patients.

METHODS

We searched Medline and Embase from inception through June 1, 2022. We included randomized controlled trials or observational studies comparing anti-Xa-guided versus fixed dosing of LMWH for thromboprophylaxis in adult trauma patients. We incorporated primary data from 2 large observational cohorts. We pooled effect estimates using a random-effects model. We assessed risk of bias using the ROBINS-I tool for observational studies and assessed certainty of findings using GRADE methodology.

RESULTS

We included 15 observational studies involving 10,348 patients. No randomized controlled trials were identified. determined that, compared to fixed LMWH dosing, anti-Xa-guided dosing may reduce deep vein thrombosis [adjusted odds ratio (aOR); 0.52, 95% CI: 0.40-0.69], pulmonary embolism (aOR: 0.48, 95% CI: 0.30-0.78) or any VTE (aOR: 0.54, 95% CI: 0.42-0.69), though all estimates are based on low certainty evidence. There was an uncertain effect on mortality (aOR: 1.06, 95% CI: 0.85-1.32) and bleeding events (aOR: 0.84, 95% CI: 0.50-1.39), limited by serious imprecision. We used several sensitivity and subgroup analyses to confirm the validity of our assumptions.

CONCLUSION

Anti-Xa-guided dosing may be more effective than fixed dosing for prevention of deep vein thrombosis, pulmonary embolism, and VTE for adult trauma patients. These promising findings justify the need for a high-quality randomized study with the potential to deliver practice changing results.

Race does matter: venous thromboembolism in trauma patients with isolated severe pelvic fractures

PURPOSE

Studies in non-trauma populations have shown that Black patients have a higher risk of venous thromboembolism (VTE) compared to other races. We sought to determine whether this association exists in trauma patients. The incidence of VTE is particularly high following severe pelvic fractures. To limit confounding factors associated with additional injuries, we examined patients with isolated blunt severe pelvic fractures.

METHODS

The TQIP database (2013-2017) was queried for all patients who sustained isolated blunt severe pelvic fractures (AIS ≥ 3) and received VTE prophylaxis (VTEp) with either unfractionated heparin or low molecular weight heparin. The study groups were Asian, Black, and White race as defined by TQIP. The primary outcome was differences in the rate of thromboembolic events.

RESULTS

A total of 9491 patients were included in the study. Of these, 232 (2.4%) were Asian, 1238 (13.0%) Black, and 8021 (84.5%) White. There was no significant difference in the distribution of pelvis AIS 3,4,5 between the groups. Black patients had a significantly higher incidence of VTE, DVT and PE compared to Asians and Whites. After adjusting for differences between the groups, Black patients had higher odds of developing pulmonary embolism (OR 1.887, 95% CI 1.101-3.232, p = 0.021) compared to White patients.

CONCLUSIONS

In this nationwide study of trauma patients with severe pelvic fractures, Black patients were more likely to develop pulmonary embolism compared to White patients. Further research to identify the determinants of racial disparities in trauma-related VTE is warranted, to target interventions that can improve VTE outcomes for all patients.

Incidence, risk factors and potential timing of occurrence of pulmonary embolism in fatal trauma: An autopsy based case-control study on 2705 victims

BACKGROUND

Pulmonary embolism (PE) following trauma is a potentially preventable but highly lethal complication. We sought to investigate the incidence, risk factors and potential timing of occurrence of post-traumatic PE in a large cohort of trauma fatalities.

METHODS

A case-control study on 9266 consecutive trauma fatalities (between 1996 and 2005) from a regional autopsy-based trauma registry. Injuries were classified according to the Abbreviated Injury Scale-1990 edition (AIS-90) and the Injury Severity Score (ISS) was calculated. Hospitalized victims were categorized according to the presence or absence of PE on autopsy. Univariate comparisons and multivariate logistic regression analysis for probabilities of association (odds ratios-OR) were performed.

RESULTS

Out of 2705 subjects who met the inclusion criteria, 116 had autopsy findings of PE and constituted the PE group (incidence of 4,3%), while the remaining victims formed the control group. The survival time of the PE group ranged from 0.66 to 104.73 days. Victims in the PE group were older (median age 69.5 vs 59), had lower ISS values (median 16 vs 26) and longer post-injury survival times (median 13.6 vs 5.7 days). Positively associated risk factors were AIS2-5 pelvic ring injuries (OR:2.23) and secondary deaths following an uneventful hospital discharge (OR:3.97), while AIS2-5 head (OR:0.33) and abdominal injuries (OR:0.23) showed a reverse association.

CONCLUSIONS

Trauma fatalities with autopsy findings of PE were associated with less severe trauma indicating that PE was likely detrimental to the fatal outcome. Both the early and delayed occurrence of PE was reaffirmed. Prophylactic measures should be initiated promptly and extended post discharge for high risk patients to prevent secondary deaths.

Haemostasis and Inflammatory Parameters as Potential Diagnostic Biomarkers for VTE in Trauma-Immobilized Patients

Venous thromboembolism (VTE), which encompasses deep venous thrombosis (DVT) and pulmonary embolism (PE), is a major public health concern due to its high incidences of morbidity and mortality. Patients who have experienced trauma with prolonged immobilization are at an increased risk of developing VTE. Plasma D-dimer levels have been known to be elevated in trauma patients, and they were closely correlated with the number of fractures. In other words, plasma D-dimer levels cannot be used as the only indicator of VTE in trauma cases. Given the limitations, further study is needed to explore other potential biomarkers for diagnosing VTE. To date, various established and novel VTE biomarkers have been studied in terms of their potential for predicting VTE, diagnostic performance, and improving clinical therapy for VTE. Therefore, this review aims to provide information regarding classic and essential haemostasis (including prothrombin time (PT), activated partial thromboplastin time (aPTT), D-dimer, fibrinogen, thrombin generation, protein C, protein S, antithrombin, tissue factor pathway inhibitor, and platelet count) and inflammatory biomarkers (C-reactive protein, erythrocyte sedimentation rate, and soluble P-selectin) as potential diagnostic biomarkers that can predict the risk of VTE development among trauma patients with prolonged immobilization. Thus, further advancement in risk stratification using these biomarkers would allow for a better diagnosis of patients with VTE, especially in areas with limited resources.

A case of early pulmonary embolism following blunt trauma to chest and a long bone fracture: a case report

Background

After substantial trauma, pulmonary embolism (PE) carries a high risk of morbidity and mortality. Early post-traumatic PE in the absence of deep vein thrombosis (DVT) is a distinct entity that might be connected to rare mechanisms or unidentified biochemical processes.

Case presentation

A driver of a car was presented with worsening chest pain and shortness of breath (SOB) following a road traffic accident in which he suffered an impact on the chest against the steering wheel and a closed fracture of the right femur. Radiological investigations revealed a pulmonary embolism in the left posterior segment pulmonary artery, without evidence of internal chest injuries or DVT within 12 h from the incident. D-dimer, troponin I, and creatinine kinase were elevated without evidence of myocardial infarction or myocardial injury. Other parameters were within the normal range.

Conclusions

Possibilities of early PE in the absence of detectable DVT could be due to hyper-coagulability states, clots from the lower extremity completely getting detached and embolizing to the pulmonary circulation, screening errors, and "de novo" thrombi in the pulmonary circulation. Chest trauma is an identified risk factor for early or late pulmonary embolism. Action of the post-traumatic adrenergic response causing vascular endothelial inflammation and the synthesis of circulating adhesion molecules leading to localized thrombosis have also been suggested as causes for this phenomenon. A greater understanding of rare risk factors for early PE and the possibility of rare complications of chest trauma is useful in detecting and treating them in time, reducing morbidity and mortality.

The Risk Assessment Profile is suboptimal for guiding duplex ultrasound surveillance in trauma patients

Background

The utility of the Risk Assessment Profile (RAP) score in predicting VTE was assessed, and VTE risk factors identified to guide a duplex ultrasound (DUS) protocol in injured patients.

Methods

Secondary analysis of prospective data on trauma inpatients (March 2017-September 2019), with admission RAP ≥5. Inhospital VTE patients compared to those without. Regression analyses in DVT, PE and proximal DVT, and ROC analysis evaluating RAP's VTE predictability were performed.

Results

1989 patients were analyzed. VTE was identified in 163(8.2%), DVT 159(8.0%), and PE 10(0.5%) patients. Strongest VTE predictors were massive transfusion (OR 5.97, p = 0.005) and spinal cord injury (OR 2.43, p = 0.03). AUC 0.61 (p < 0.001) on ROC analysis evaluating RAP on VTE. Abdominal injury and major surgery were unique risk factors to non-screened patients.

Conclusion

Performance of RAP to predict VTE was moderate. VTE predictor variables could serve as the foundation for a novel approach guiding DUS surveillance. Derivation and validation are warranted.

Clinical Characteristics and Risk Factors for Early versus Late Pulmonary Embolism in Trauma Patients: A Retrospective, Observational Study

Background

We sought to evaluate the clinical characteristics and risk factors for early versus late pulmonary embolism (PE) in trauma patients.

Methods

This was a retrospective analysis of injured patients who presented with a confirmed PE between 2013 and 2019. Data were analysed and compared for patients with early PE (≤4 days) versus late PE (>4 days post-trauma).

Results

The study included 82 consecutive trauma patients with confirmed diagnosis of PE. The mean age of patients was 42.3 ± 16.2 years. The majority were males (79.3%) and the median time from injury to PE was 10 days. Of the PE cases, 24 (29.3%) had early PE, while 58 (70.7%) had late PE. The early PE group had higher rates of surgical intervention within 24 hours of admission than the late PE group (p = 0.001). Also, the rate of sub-segmental thrombi was significantly higher in the early PE group (p = 0.01). The late PE group sustained more moderate-to-severe injuries ie, GCS ED <13 (p = 0.03) and the median time from injury to PE diagnosis was 15 days (p = 0.001). After adjusting for the potential covariates, surgery within 24 hours of admission [adjusted odds ratio 37.58 (95% confidence interval 3.393-416.20), p = 0.003] was found to be significant independent predictor of early PE in trauma patients.

Conclusion

One-third of post-trauma PEs occurs early after trauma and the surgical intervention within the first 24 hours of admission is a major risk factor. A prospective study is needed to develop an objective risk assessment for the prevention and detection of early and late PE post-trauma.

Preperitoneal Pelvic Packing for Hypotension Has a Greater Risk of Venous Thromboembolism Than Angioembolization: Management of Refractory Hypotension in Closed Pelvic Ring Injury

BACKGROUND

Patients with traumatic pelvic ring injury may present with hypotension secondary to hemorrhage. Preperitoneal pelvic packing (PPP) and angioembolization (AE) are alternative interventions for management of hypotension associated with pelvic ring injury refractory to resuscitation and circumferential compression. We hypothesized that PPP may be independently associated with increased risk of venous thromboembolism (VTE) compared with AE in patients with hypotension and pelvic ring injury.

METHODS

Adult patients with pelvic ring injury and hypotension managed with PPP or AE were retrospectively identified in the Trauma Quality Improvement Program (TQIP) database from 2015 to 2019. Patients were matched on a propensity score for receiving PPP based on patient, injury, and treatment factors. The primary outcome was the risk of VTE after matching on the propensity score for treatment. The secondary outcomes included inpatient clinically important deep vein thrombosis, pulmonary embolism, respiratory failure, mortality, unplanned reoperation, sepsis, surgical site infection, hospital length of stay, and intensive care unit (ICU) length of stay.

RESULTS

In this study, 502 patients treated with PPP and 2,439 patients treated with AE met inclusion criteria. After propensity score matching on age, smoking status, Injury Severity Score, Tile B or C pelvic ring injury, bilateral femoral fracture, serious head injury, units of plasma and platelets given within 4 hours of admission, laparotomy, and level-I trauma center facility designation, 183 patients treated with PPP and 183 patients treated with AE remained. PPP, compared with AE, was associated with a 9.8% greater absolute risk of VTE, 6.5% greater risk of clinically important deep vein thrombosis, and 4.9% greater risk of respiratory failure after propensity score matching.

CONCLUSIONS

PPP for the management of hypotension associated with pelvic ring injury is associated with higher rates of inpatient VTE events and sequelae compared with AE.

LEVEL OF EVIDENCE

Prognostic Level III . See Instructions for Authors for a complete description of levels of evidence.

Epidemiology and clinical characteristics of posttraumatic hospitalized patients with symptoms related to venous thromboembolism: a single-center retrospective study

Purpose

The aim of this study was to investigate the epidemiology of trauma inpatients with venous thromboembolism (VTE) symptoms diagnosed using computed tomographic angiography (CTA) in Korea.

Methods

In total, 7,634 patients admitted to the emergency department of Gachon University Gil Medical Center, a tertiary hospital, and hospitalized between July 1, 2018 and December 31, 2020 were registered for this study. Of these patients, 278 patients who underwent CTA were enrolled in our study.

Results

VTE was found in 120 of the 7,634 patients (1.57%), and the positive diagnosis rate of the 278 patients who underwent CTA was 43.2% (120 of 278). The incidence of VTE was statistically significantly higher among those with severe head and neck injuries (Abbreviated Injury Scale, 3-5) than among those with nonsevere head and neck injuries (Abbreviated Injury Scale, 0-2; P=0.038). In a subgroup analysis, the severe and nonsevere head and neck injury groups showed statistically significant differences in known independent risk factors for VTE. In logistic regression analysis, the adjusted odds ratio of severe head and neck injury (Abbreviated Injury Scale, 3-5) for VTE was 1.891 (95% confidence interval, 1.043-3.430).

Conclusions

Trauma patients with severe head and neck injuries are more susceptible to VTE than those with nonsevere head and neck injuries. Thus, physicians must consider CTA as a priority for the diagnosis of VTE in trauma patients with severe head and neck injuries who show VTE-associated symptoms.

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.

Venous thromboembolism prophylaxis with low molecular weight heparin versus unfractionated heparin for patients undergoing operative treatment of closed femoral shaft fractures

BACKGROUND

The objective of this study was to compare inpatient mortality rates for patients with operatively treated closed femoral shaft fractures (AO/OTA 32 A-C) who received venous thromboembolism (VTE) prophylaxis with either low molecular weight heparin (LMWH) or unfractionated heparin.

METHODS

This was a retrospective cohort study of a national database of patients presenting to Level I through IV trauma centers in the United States. All patients ≥18 years of age who sustained an operatively treated closed femoral shaft fracture were included. The primary outcome of inpatient mortality was compared between two groups: those who received LMWH or unfractionated heparin for VTE prophylaxis. Secondary outcomes were complications including VTE and bleeding events. Groups were compared using a multivariate regression model.

RESULTS

There were 2058 patients included in the study. Patients who received VTE prophylaxis with LMWH had lower odds of inpatient mortality compared to patients who received VTE prophylaxis with unfractionated heparin (OR 0.19; 95% CI 0.05 to 0.68, p = 0.011).

CONCLUSIONS

VTE prophylaxis with LMWH is associated with lower inpatient mortality compared to VTE prophylaxis with unfractionated heparin for patients undergoing operative treatment of closed femoral shaft fractures. To our knowledge this is the first study to report these associations for a specific subset of orthopedic trauma patients.

The risk of thromboembolic events with early intravenous 2- and 4-g bolus dosing of tranexamic acid compared to placebo in patients with severe traumatic bleeding: A secondary analysis of a randomized, double-blind, placebo-controlled, single-center trial

BACKGROUND

Screening for the risk of thromboembolism (TE) due to tranexamic acid (TXA) in patients with severe traumatic injury has not been performed in randomized clinical trials. Our objective was to determine if TXA dose was independently-associated with thromboembolism.

STUDY DESIGN AND METHODS

This is a secondary analysis of a single-center, double-blinded, randomized controlled trial comparing placebo to a 2-g or 4-g intravenous TXA bolus dose in trauma patients with severe injury. We used multivariable discrete-time Cox regression models to identify associations with risk for thromboembolic events within 30 days post-enrollment. Event curves were created using discrete-time Cox regression.

RESULTS

There were 50 patients in the placebo group, 49 in the 2-g, and 50 in the 4-g TXA group. In adjusted analyses for thromboembolism, a 2-g dose of TXA had an hazard ratio (HR, 95% confidence interval [CI]) of 3.20 (1.12-9.11) (p = .029), and a 4-g dose of TXA had an HR (95% CI) of 5.33 (1.94-14.63) (p = .001). Event curves demonstrated a higher probability of thromboembolism for both doses of TXA compared to placebo. Other parameters independently associated with thromboembolism include time from injury to TXA administration, body mass index, and total blood products transfused.

DISCUSSION

In patients with severe traumatic injury, there was a dose-dependent increase in the risk of at least one thromboembolic event with TXA. TXA should not be withheld, but thromboembolism screening should be considered for patients receiving a dose of at least 2-g TXA intravenously for traumatic hemorrhage.

THE EFFICACY OF WEIGHT-BASED ENOXAPARIN DOSING FOR VTE-PROPHYLAXIS IN TRAUMA PATIENTS: A SYSTEMATIC REVIEW AND META-ANALYSIS

BACKGROUND

Trauma patients are at high risk of developing venous thromboembolism (VTE), and standard dosing enoxaparin regimens may be inadequate for prophylaxis. This meta-analysis was performed to clarify the efficacy of alternative dosing regimens for VTE prophylaxis in this high-risk group. The objective of this systematic review was to review the evidence regarding weight-based dosing of enoxaparin for VTE prophylaxis in trauma patients.

METHODS

A systematic database search was undertaken for studies comparing standard vs weight-based dosing of enoxaparin for VTE prophylaxis in adult trauma patients, aged ≥18 years. The primary outcome was the achievement of Anti-Factor Xa (AFXa) levels within the prophylactic range. Secondary outcomes included: sub-prophylactic AFXa levels, supra-prophylactic AFXa levels, VTE incidence and bleeding events. Meta-analysis was conducted using both fixed- and random-effects models, and presented as odds ratios (OR), risk ratios (RR) and risk differences (RD) with 95% confidence intervals (CI).

RESULTS

Four cohort studies were eligible for inclusion. Compared to standard dosing, weight-based enoxaparin prophylaxis dosing was associated with increased odds of prophylactic AFXa levels (OR = 5.85., 95%CI: 3.02-11.30, p < 0.00001) and reduced risk of sub-prophylactic AFXa levels (RR = 3.97, 95%CI: 3.02-5.22, p < 0.00001). Standard dosing was associated with a reduced risk of supra-therapeutic AFXa levels (RR = 0.23, 95%CI: 0.11-0.50, P = 0.0002), but this was not associated with a difference in risk of bleeding events (RD = -0.00, 95%CI: -0.02-0.01, P = 0.55). There was no statistical difference in incidence VTE between the two groups (RD = 0.01, 95%CI: -0.02-0.03, P = 0.64).

CONCLUSIONS

Compared with standard dosing, weight-based enoxaparin dosing regimens are associated with increased odds of prophylactic range AFXa levels. Further investigation is required to determine if this translates into improved VTE prophylaxis and reduced VTE incidence.

LEVEL OF EVIDENCE

Systematic Review, level III.

High Altitude as a Risk Factor for Venous Thromboembolism in Tibial Plateau Fractures

Background: Tibial plateau fractures are often significant injuries that can require complex surgical interventions with prolonged perioperative immobilization, thereby increasing the risk of developing venous thromboembolic (VTE) events, specifically, deep vein thrombosis (DVT) and pulmonary embolism (PE). Risk stratification is paramount for guiding VTE prophylaxis. Although high altitude has been suggested to create a prothrombotic state, virtually no studies have explored its clinical effects in lower extremity trauma. The purpose of this study was to compare surgical fixation of tibial plateau fractures at high and low altitudes and its effects on post-operative VTE development.

Methods: The Truven MarketScan claims database was used to retrospectively identify patients who underwent surgical fixation of isolated and closed tibial plateau fractures using Current Procedural Terminology (CPT) codes over a 10-year period. Extraneous injuries were excluded using the International Classification of Diseases, 10^th edition (ICD-10), and CPT codes. Patient demographics, comorbidities, and DVT chemoprophylaxis prescriptions were obtained. Patients were partitioned into high altitude (>4000 feet) or low altitude (<100 feet) cohorts based on the zip codes of their surgery locations. One-to-one matching and univariate analysis were used to assess and control any baseline discrepancies between cohorts; multivariate regression was then performed between cohorts to determine the odds ratios (OR) for developing VTEs post-operatively.

Results: There were 7,832 patients included for analysis. There was no statistical difference between high and low altitude cohorts in developing VTEs within 30 days post-operatively. Higher altitudes were associated with increased odds of developing DVT (OR 1.21, p = 0.043) and PE (OR 1.27, p = 0.037) within 90 days post-operatively.

Conclusions: Surgical fixation of tibial plateau fractures is associated with an increased risk of developing VTEs at high altitudes within 90 days post-operatively. Understanding such risk factors in specific orthopaedic patient populations is essential for optimizing DVT prophylaxis protocols. Further studies should investigate this relationship and the role of DVT prophylaxis regimens in this population. 

Chemoprophylaxis for venous thromboembolism in pelvic and/or acetabular fractures: A systematic review

BACKGROUND

It is unclear which pharmacological agents, and at what dosage and timing, are most effective for venous thromboembolism (VTE) prophylaxis in patients with pelvic/acetabular fractures.

METHODS

We searched the Cochrane Database of Systematic Reviews, Embase, Web of Science, EBSCO, and PubMed on October 3, 2020, for English-language studies of VTE prophylaxis in patients with pelvic/acetabular fractures. We applied no date limits. We included studies that compared efficacy of pharmacological agents for VTE prophylaxis, timing of administration of such agents, and/or dosage of such agents. We recorded interventions, sample sizes, and VTE incidence, including deep vein thrombosis (DVT) and pulmonary embolism.

RESULTS

Two studies (3604 patients) compared pharmacological agents, reporting that patients who received direct oral anticoagulants (DOACs) were less likely to develop DVT than those who received low molecular weight heparin (LMWH) (p < 0.01). Compared with unfractionated heparin (UH), LMWH was associated with lower odds of VTE (odds ratio [OR] = 0.37, 95% confidence interval [CI]: 0.22-0.63) and death (OR = 0.27, 95% CI: 0.10-0.72). Three studies (3107 patients) compared timing of VTE prophylaxis, reporting that late prophylaxis was associated with higher odds of VTE (OR = 1.9, 95% CI: 1.2-3.2) and death (OR = 4.0, 95% CI: 1.5-11) and higher rates of symptomatic DVT (9.2% vs. 2.5%, p = 0.03; and 22% vs. 3.1%, p = 0.01). One study (31 patients) investigated dosage of VTE prophylaxis, reporting that a higher proportion of patients with acetabular fractures were underdosed (23% of patients below range of anti-Factor Xa [aFXa] had acetabular fractures vs. 4.8% of patients within adequate range of aFXa, p<0.01).

CONCLUSIONS

Early VTE chemoprophylaxis (within 24 or 48 h after injury) was better than late administration in terms of VTE and death. Many patients with acetabular fractures are underdosed with LMWH, with inadequate aFXa levels. Compared with UH, LMWH was associated with lower odds of VTE and death. DOACs were associated with lower risk of DVT compared with LMWH.

LEVEL OF EVIDENCE

III, systematic review of retrospective cohort studies.