Venous thromboembolism prophylaxis in neurosurgical trauma patients

Early venous thromboembolism chemoprophylaxis in traumatic brain injury requiring neurosurgical intervention: Safe and effective

BACKGROUND

Traumatic brain injury patients who require neurosurgical intervention are at the highest risk of worsening intracranial hemorrhage. This subgroup of patients has frequently been excluded from prior research regarding the timing of venous thromboembolism chemoprophylaxis. This study aims to assess the efficacy and safety of early venous thromboembolism chemoprophylaxis in patients with traumatic brain injuries requiring neurosurgical interventions.

METHODS

This is a single-center retrospective review (2016-2020) of traumatic brain injury patients requiring neurosurgical intervention admitted to a level I trauma center. Interventions included intracranial pressure monitoring, subdural drain, external ventricular drain, craniotomy, and craniectomy. Exclusion criteria included neurosurgical intervention after chemoprophylaxis initiation, death within 5 days of admission, and absence of chemoprophylaxis. The total population was stratified into Early (≤72 hours of intervention) versus Late (>72 hours after intervention) chemoprophylaxis initiation.

RESULTS

A total of 351 patients met the inclusion criteria, of whom 204 (58%) had early chemoprophylaxis initiation. Overall, there were no significant differences in baseline and admission characteristics between cohorts. The Early chemoprophylaxis cohort had a statistically significant lower venous thromboembolism rate (5% vs 13%, P < .001) with no increased risk of worsening intracranial hemorrhage (10% vs 13%, P = .44) or neurosurgical reintervention (8% vs 10%, P = .7). On subgroup analysis, a total of 169 patients required either a craniotomy or a craniectomy before chemoprophylaxis. The Early chemoprophylaxis cohort had statistically significant lower venous thromboembolism rates (2% vs 11%, P < .001) with no increase in intracranial hemorrhage (8% vs 11%, P = .6) or repeat neurosurgical intervention (8% vs 10%, P = .77).

CONCLUSION

Venous thromboembolism prophylaxis initiation within 72 hours of neurosurgical intervention is safe and effective. Further prospective research is warranted to validate the results of this study.

Venous thromboembolism in aneurysmal subarachnoid hemorrhage: Risk factors and timing of chemoprophylaxis

INTRODUCTION

Venous thromboembolism (VTE) is a significant contributor to morbidity and mortality among patients recovering from aneurysmal subarachnoid hemorrhage (aSAH). Prophylactic heparin reduces the risk of VTE, but the optimal timing for its initiation among aSAH patients remains unclear.

OBJECTIVE

To conduct a retrospective study assessing risk factors for VTE and optimal timing of chemoprophylaxis in patients treated for aSAH.

METHODS

From 2016-2020, 194 adult patients were treated for aSAH at our institution. Patient demographics, clinical diagnoses, complications, pharmacologic interventions, and outcomes were recorded. Risk factors for symptomatic VTE (sVTE) were analyzed via Chi-squared, univariate, and multivariate regression.

RESULTS

In total 33 patients presented with sVTE (25 DVT, 14 PE). Patients with sVTE had longer hospital stays (p < 0.01) and worse outcomes at one-month (p < 0.01) and three-month follow-up (p = 0.02). Univariate predictors of sVTE included male sex (p = 0.03), Hunt Hess score (p = 0.01), Glasgow Coma scale (p = 0.02), intracranial hemorrhage (p = 0.03), hydrocephalus requiring external ventricular drain (EVD) placement (p < 0.01), and mechanical ventilation (p < 0.01). Only hydrocephalus requiring EVD (p = 0.01) and ventilator use (p = 0.02) remained significant upon multivariate analysis. Patients with delayed heparin introduction were significantly more likely to sustain sVTE on univariate analysis (p = 0.02) with a trend-level significance on multivariate analysis (p = 0.07).

CONCLUSIONS

Patients with aSAH are more likely to develop sVTE following use of perioperative EVD or mechanical ventilation. sVTE leads to longer hospital stays and worse outcomes among patients treated for aSAH. Delayed heparin initiation increases the risk of sVTE. Our results may help guide surgical decision-making during recovery from aSAH and improve VTE-related postoperative outcomes.

Chemoprophylactic Anticoagulation 72 Hours After Spinal Fracture Surgical Treatment Decreases Venous Thromboembolic Events Without Increasing Surgical Complications

Background

Prophylactic anticoagulation is commonly used following operative treatment of spinal fractures to prevent Venous Thromboembolism (VTE) but carries a risk of bleeding complications. The purpose of the study was to compare VTE and bleeding complications for MID (≤72h) versus LATE (>72h) chemoprophylaxis timing after spinal fracture operative intervention.

Methods

This is a retrospective review of patients treated for spinal fractures that received anticoagulation chemoprophylaxis between May 2015 and June 2019. Chemoprophylaxis initiation timing (MID vs. LATE) was the primary grouping variable. Patients with traumatic brain injury or evidence of intracranial or intraspinal bleed were excluded. Demographics, injury mechanisms, operative procedures, timing of administration of VTE prophylaxis, Injury Severity Score (ISS) and Spine Abbreviated Injury Scale (AIS), and complications including VTE and bleeding complications were collected. Predictors of VTE were identified using a binary logistic regression.

Results

Eighty-eight patients (65M, 23F) met inclusion criteria. The median age was 55 years, and median Injury Severity Score (ISS) was 14. MID had 68 patients and LATE had 20. Nine patients developed VTE (6 LATE, 3 MID, p<0.01). Three patients developed bleeding complications, and all occurred in the LATE group (p=0.01). ISS (p<0.01) and GCS (p<0.01) also correlated with an increased VTE rate.

Conclusions

Chemoprophylactic anticoagulation at 72 hours in surgically treated spinal fracture patients demonstrates a lower VTE rate without increasing complications. VTE prophylaxis can be initiated at 72 hours following spine fixation to decrease postinjury morbidity and mortality in this high-risk patient population.

Predictive risk factors for venous thromboembolism in neurosurgical patients: A retrospective analysis single center cohort study

Background

Venous thromboembolism (VTE) has a major effect on morbidity and mortality in neurosurgical patients. However, identifying risk factors that may be useful in practice is a challenge. The purpose of this study was to investigate the incidence and determine the predictors of VTE in patients undergoing neurosurgery.

Materials and methods

This retrospective, single-center cohort study was conducted on adult patients admitted to a private hospital for a primary elective neurosurgical procedure between January 2015 and December 2020. Univariate analysis was used to examine clinical factors, and multivariable regression analysis was used to identify predictors of VTE. The area under the receiver-operating characteristic (AUROC) curve demonstrated the fitting model and discrimination power.

Results

A total of 350 patients who underwent neurological surgery were identified. There were 26 patients (7.4%) with VTE. The final predictors were found to be statistically significant in the multivariate binary logistic regression analysis, including non-Asian populations (p value < 0.001, odds ratio [OR]: 6.11, 95% confidence interval [CI] = 2.20–16.89), lack of postoperative ambulation (p value = 0.009, OR: 9.25, 95% CI = 1.17–48.83), and septic shock complication (p value = 0.001, OR: 5.36, 95% CI = 1.46–19.62). The AUROC was 0.708 (95% CI 0.61–0.80).

Conclusion

Although the incidence of VTE in patients receiving neurosurgery is minimal, it is also higher in non-Asian patients, those who lack of postoperative ambulation, and patients with septic shock complications. This approach may be useful to predict thromboembolism in neurosurgical patients. External validation of the prognostic model requires more investigation.

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Venous thromboembolism (VTE) complications can be a major cause of morbidity and even death in neurosurgical patients.

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The standard therapy for the appropriate prophylaxis remains unclear.

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Whether or not to use pharmacological prophylaxis is determined by a higher-risk category of individuals.

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Based on information from risk factors, it may be a benefit guide for proper VTE prophylaxis.

Progression of Intracranial Hemorrhage After Chemical Prophylaxis Using Low-Molecular-Weight Heparin in Patients With Traumatic Brain Injury

INTRODUCTION

Chemical prophylaxis using low-molecular-weight heparin (LMWH) is considered a standard of care for venous thromboembolism in trauma patients. Our center performs a head computed tomography (CT) scan 24 hours after initiation with prophylactic LMWH in the setting of a known traumatic brain injury (TBI). The purpose was to determine the overall incidence of ICH progression after chemoprophylaxis in patients with a TBI.

METHODS

This retrospective study was performed at a Level I trauma center, from 1/1/2014 to 12/31/2017. Study patients were drawn from the institution's trauma registry based on Abbreviated Injury Score codes.

RESULTS

778 patients met all inclusion criteria after initial chart review. The proportion of patients with an observed radiographic progression of intracranial hemorrhage after LMWH was 5.8%. 3.1% of patients had a change in clinical management. Observed radiographic progression after LMWH prophylaxis and the presence of SDH on initial CT, the bilateral absence of pupillary response in the emergency department, and a diagnosis of dementia were found to have statistically significant correlation with bleed progression after LMWH was initiated.

CONCLUSION

Over a 4-year period, the use of CT to evaluate for radiographic progression of traumatic intracranial hemorrhage 24 hours after receiving LMWH resulted in a change in clinical management for 3.1% of patients. The odds of intracranial hemorrhage progression were approximately 6.5× greater in patients with subdural hemorrhage on initial CT, 3.1× greater in patients with lack of bilateral pupillary response in ED, and 4.2× greater in patients who had been diagnosed with dementia.

Venous Thromboembolism Chemoprophylaxis in Trauma and Emergency General Surgery Patients: A Systematic Review

BACKGROUND

Appropriate venous thromboembolism (VTE) chemoprophylaxis in trauma and emergency general surgery (EGS) patients is crucial.

OBJECTIVE

The purpose of this study is to review the recent literature and offer recommendations for VTE chemoprophylaxis in trauma and EGS patients.

METHODS

We conducted a literature search from 2000 to 2021 for articles investigating VTE chemoprophylaxis in adult trauma and EGS patients. This study was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines.

RESULTS

Our search resulted in 34 articles. Most studies showed low-molecular-weight heparin (LMWH) is similar to unfractionated heparin (UFH) for VTE prevention; however, LMWH was more commonly used. Adjusted chemoprophylaxis dosing did not change the VTE rate but the timing did. Direct oral anticoagulants (DOACs) have been shown to be safe and effective in trauma and traumatic brain injury (TBI)/spinal cord injury (SCI). Studies showed VTE prophylaxis in EGS can be inconsistent and improves with guidelines that lower VTE events.

CONCLUSIONS

There may be no benefit to receiving LMWH over UFH in trauma patients. In addition, different drugs under the class of LMWH do not change the incidence of VTE. Adjusted dosing of enoxaparin does not seem to affect VTE incidence. The use of DOACs in the trauma TBI and SCI setting has been shown to be safe and effective in reducing VTE. One important consideration with VTE prophylaxis may be the timing of prophylaxis initiation, specifically as it relates to TBI, with a higher likelihood of developing VTE as time progresses. EGS patients are at a high risk of VTE. Improved compliance with clinical guidelines in this population is correlated with decreased thrombotic events.

A Stitch in Time Saves Clots: Venous Thromboembolism Chemoprophylaxis in Traumatic Brain Injury

BACKGROUND

Venous thromboembolism chemoprophylaxis (VTE-CHEMO) is often delayed in patients with traumatic brain injury because of the concern for intracranial hemorrhage (ICH) progression. We hypothesize that (1) late time to VTE-CHEMO (≥48 h) is associated with higher incidence of VTE, and (2) VTE-CHEMO use does not correlate with ICH progression.

MATERIALS AND METHODS

This is a multiinstitutional retrospective study of patients with traumatic brain injury admitted between 2014 and 2016. Inclusion criteria were head Abbreviated Injury Code ≥2, ICH present on initial head computed tomography, and two or more head computed tomography scans after admission. The primary outcome was VTE, and the secondary outcome was ICH progression. Patients were classified as receiving VTE-CHEMO early (<48 h) or late (≥48 h). Multivariable analysis with Cox proportional hazards regression was performed.

RESULTS

Overall, 1803 patients were included. Patients with VTE (n = 137) were more likely to have spinal cord injury, blunt cerebrovascular injury, pelvic or femur fractures, and missed VTE-CHEMO doses. After multivariable regression, body mass index >30 (hazard ratio [HR], 1.05; P = 0.002), Injury Severity Score (HR, 1.004; P < 0.001), pelvic or femur fractures (HR, 1.05; P < 0.0001), spinal cord injury (HR, 1.28; P = 0.02), and missed VTE-CHEMO doses (HR, 1.08; P = 0.01) were significant predictors of VTE. In those who required neurosurgery, late VTE-CHEMO predicted VTE (HR, 1.21; P = 0.0001). Overall, 32% patients experienced ICH progression, which did not correlate with VTE-CHEMO use or timing.

CONCLUSIONS

This multicenter study highlights benefits from early VTE-CHEMO and identifies high-risk groups who may benefit from more aggressive prophylaxis. These data also emphasize risk to patients by withholding VTE-CHEMO.

Assessment of Anti-Factor Xa Levels of Patients Undergoing Colorectal Surgery Given Once-Daily Enoxaparin Prophylaxis: A Clinical Study Examining Enoxaparin Pharmacokinetics

Importance

Between 4% and 12% of patients undergoing colorectal surgery and receiving enoxaparin, 40 mg per day, have a postoperative venous thromboembolism (VTE) event. An improved understanding of why "breakthrough" VTE events occur despite guideline-compliant prophylaxis is an important patient safety question.

Objective

To determine the proportion of patients undergoing colorectal surgery who received adequate anticoagulation based on peak anti-factor Xa (aFXa) levels while receiving enoxaparin at 40 mg per day.

Design, Setting, and Participants

This prospective, nonrandomized clinical trial was conducted between February 2017 and July 2018 with 90-day follow-up at a quaternary academic medical center in the Intermountain West and included patients undergoing colorectal surgery who had surgery after receiving general anesthesia, were admitted for at least 3 days, and received enoxaparin, 40 mg once daily.

Interventions

All patients had aFXa levels measured after receiving enoxaparin 40 mg per day. Patients whose aFXa level was out of range entered the trial's interventional arm where real-time enoxaparin dose adjustment and repeated aFXa measurement were performed.

Main Outcomes and Measures

Primary outcome: in-range peak aFXa levels (goal range, 0.3-0.5 IU/mL) with enoxaparin, 40 mg per day. Secondary outcomes: (1) in-range trough aFXa levels (goal range, 0.1-0.2 IU/mL) and (2) the proportion of patients with in-range peak aFXa levels from enoxaparin, 40 mg once daily, vs the real-time enoxaparin dose adjustment protocol.

Results

Over 16 months, 116 patients undergoing colorectal surgery (65 women [56.0%]; 99 white individuals [85.3%], 13 Hispanic or Latino individuals [11.2%], and 4 Pacific Islander individuals [3.5%]; mean [range] age, 52.1 [18-85] years) were enrolled. Among 106 patients (91.4%) whose peak aFXa level was appropriately drawn, 72 (67.9%) received inadequate anticoagulation (aFXa < 0.3 IU/mL) with enoxaparin, 40 mg per day. Weight and peak aFXa levels were inversely correlated (r2 = 0.38). Forty-seven patients (77%) had a trough aFXa level that was not detectable (ie, most patients had no detectable level of anticoagulation for at least 12 hours per day). Real-time enoxaparin dose adjustment was effective. Patients were significantly more likely to achieve an in-range peak aFXa with real-time dose adjustment as opposed to fixed dosing alone (85.4% vs 29.2%, P < .001).

Conclusions and Relevance

This study supports the finding that most patients undergoing colorectal surgery receive inadequate prophylaxis from enoxaparin, 40 mg once daily. These findings may explain the high rate of "breakthrough" VTE observed in many clinical trials.

Trial Registration

ClinicalTrials.gov identifier: NCT02704052.

Venous Thromboembolism Chemoprophylaxis Within 24 Hours of Surgery for Spinal Cord Injury: Is It Safe and Effective?

OBJECTIVE

Current guidelines recommend initiation of venous thromboembolism (VTE) chemoprophylaxis within 72 hours of spinal cord injury (SCI). This study investigated the safety and efficacy of chemoprophylaxis within 24 hours of surgery for SCI.

METHODS

A retrospective review of 97 consecutive patients who underwent surgery for acute traumatic SCI at a single level 1 trauma center from 2013-2018 was performed. VTE/postoperative bleeding rates during hospitalization, demographics, medical/surgical complications, drain output, length of stay, and disposition were obtained. Chi-square with odds ratios (ORs), 1-way analysis of variance, and logistic regression were performed to establish significant differences between groups.

RESULTS

Seventy-nine patients were included, 49 received chemoprophylaxis within 24 hours and 20 within 24-72 hours. Cohort characteristics included an average age of 51.8 years, 77.2% male, 62.0% cervical, and 35.4% thoracic SCIs. Using the American Spinal Injury Association Impairment Scale (AIS), 39.2% were AIS-A injuries, 19.0% AIS-B, 25.3% AIS-C, and 16.5% AIS-D. Unfractionated heparin was administered in 88.6% of patients and 11.4% received low molecular weight heparin. Chemoprophylaxis within 24 hours of surgery was associated with a lower rate of VTE (6.1% vs. 35.0%; OR, 0.121; 95% confidence interval [CI], 0.027-0.535) and deep vein thrombosis (4.1% vs. 30.0%; OR, 0.099; 95% CI, 0.018-0.548) versus 24-72 hours. Pulmonary embolism rates were not significantly different (6.1% vs. 5.0%, p = 1.0). There were no postoperative bleeding complications and no significant difference in drain output between cohorts.

CONCLUSION

Early VTE chemoprophylaxis is effective with lower VTE rates when initiated within 24 hours of surgery for SCI and is safe with no observed postoperative bleeding complications.

Chemoprophylaxis and Venous Thromboembolism in Traumatic Brain Injury at Different Trauma Centers

Patients with severe traumatic brain injury (TBI) are at an increased risk of venous thromboembolism (VTE). Because of concerns of worsening intracranial hemorrhage, clinicians are hesitant to start VTE chemoprophylaxis in this population. We hypothesized that ACS Level I trauma centers would be more aggressive with VTE chemoprophylaxis in adults with severe TBI than Level II centers. We also predicted that Level I centers would have a lower risk of VTE. We queried the Trauma Quality Improvement Program (2010–2016) database for patients with Abbreviated Injury Scale scores of 4 and 5 of the head and compared them based on treating the hospital trauma level. Of 204,895 patients with severe TBI, 143,818 (70.2%) were treated at Level I centers and 61,077 (29.8%) at Level II centers. The Level I cohort had a higher rate of VTE chemoprophylaxis use (43.2% vs 23.3%, P < 0.001) and a shorter median time to chemoprophylaxis (61.9 vs 85.9 hours, P < 0.001). Although Level I trauma centers started VTE chemoprophylaxis more often and earlier than Level II centers, there was no difference in the risk of VTE ( P = 0.414) after controlling for covariates. Future prospective studies are warranted to evaluate the timing, safety, and efficacy of early VTE chemoprophylaxis in severe TBI patients.

Early chemoprophylaxis is associated with decreased venous thromboembolism risk without concomitant increase in intraspinal hematoma expansion after traumatic spinal cord injury

BACKGROUND

After traumatic spinal cord injury (SCI), there is increased risk of venous thromboembolism (VTE), but chemoprophylaxis (PPX) may cause expansion of intraspinal hematoma (ISH).

METHODS

Single-center retrospective study of adult trauma patients from 2012 to 2015 with SCI.

EXCLUSION CRITERIA

VTE diagnosis, death, or discharge within 48 hours. Patients were dichotomized based on early (≤48 hours) heparinoid and/or aspirin PPX. Intraspinal hematoma expansion was diagnosed intraoperatively or by follow-up radiology. We used multivariable Cox proportional hazards to estimate the effect of PPX on risk of VTE and ISH expansion controlling for age, injury severity score (ISS), complete SCI, and mechanism as static covariates and operative spine procedure as a time-varying covariate.

RESULTS

Five hundred one patients with SCI were dichotomized into early PPX (n = 260 [52%]) and no early PPX (n = 241 [48%]). Early PPX patients were less likely blunt injured (91% vs 97%) and had fewer operative spine interventions (65% vs 80%), but age (median, 43 vs 49 years), ISS (median 24 vs 21), admission ISH (47% vs 44%), and VTE (5% vs 9%) were similar. Cox analysis found that early heparinoids was associated with reduced VTE (hazard ratio [HR], 0.37; 95% confidence interval [CI], 0.16-0.84) and reduced pulmonary embolism (PE) (HR, 0.20; 95% CI, 0.06-0.69). The estimated number needed to treat with heparinoids was 10 to prevent one VTE and 13 to prevent one PE at 30 days. Early aspirin was not associated with reduced VTE or PE. Seven patients (1%) had ISH expansion, of which four were on PPX at the time of expansion. Using heparinoid and aspirin as time-varying covariates, neither heparinoids (HR, 1.90; 95% CI, 0.32-11.41) nor aspirin (HR, 3.67; 95% CI, 0.64-20.88) was associated with ISH expansion.

CONCLUSION

Early heparinoid therapy was associated with decreased VTE and PE risk in SCI patients without concomitant increase in ISH expansion.

LEVEL OF EVIDENCE

Therapeutic, level IV.