# Prophylactic anticoagulation in traumatic subdural hematoma

## TL;DR

This study examines the timing of anticoagulation after traumatic brain injury and subdural hematoma surgery, finding no link between early prophylactic anticoagulation and increased bleeding or clotting risks.

## Contribution

The study provides new evidence that early prophylactic anticoagulation does not increase postoperative bleeding or thromboembolic events in patients with traumatic subdural hematoma.

## Key findings

- Postoperative intracranial hemorrhage was more common than thromboembolic events in the studied patient cohort.
- Prophylactic anticoagulation within 24–48 hours after surgery did not increase the risk of postoperative bleeding.
- Delayed anticoagulation was associated with postoperative hemorrhage, but not due to prophylactic anticoagulation itself.

## Abstract

Severe traumatic brain injury (TBI) with acute subdural hematoma (SDH) is common in neurosurgical care. Especially due to demographic development, it becomes increasingly coincident with preexisting therapeutic anticoagulation and comorbidity, such as atrial fibrillation or coagulative disorders. High-velocity trauma mechanisms become rarer, while low-impact trauma to the skull with acute-on-chronic subdural hemorrhage gets relatively more frequent. In this study we elucidate the timing of perioperative prophylactic AC and its influence on morbidity and mortality as well as complications after neurosurgical treatment. We focused especially on postoperative intracranial hemorrhage (PH) and thromboembolic events (TE). For this retrospective data analysis, 259 patients who suffered from severe TBI with consecutive subdural hematoma between 01/01/2014 and 31/12/2019 were included. We followed up for the length of stay. We assessed various biographical and clinical data for risk factors and focused on the connection between time-point of AC and adverse events. Subgroup analyses were performed for TE and PH that either required surgical intervention or was managed conservatively with radiological follow-up. Statistical analysis was performed using receiver operating characteristic curve analyses, Mann-Whitney U Test, Chi-square test, Fisher’s exact test and univariate binomial logistic regression. P-values below 0.05 were considered statistically significant. TE were relatively rare in this cohort (n = 14, 5.4%). The more common adverse event was PH (n = 34, 13.1%), with a total of 28 patients (10.8%) needing surgical revision. Though PH was correlated to a delay in AC (p = 0.010), there was no correlation between early prophylactic AC and PH (p = 0.287) or TE (p = 0.444), respectively. Furthermore, only 4 patients had been administered AC before the PH. In this context, AC was delayed purposely after PH, explaining the significant correlation between PH and delayed AC. Occurrence of PH significantly decreased overall survival (p = 0.022), while TE did not (p = 0.357). Prophylactic AC within 24–48 h after surgery did not result in more frequent PH. Our data on AC timing suggest that PH is not caused by prophylactic AC.