Impact of time to resumption of antithrombotic therapy on outcomes after surgical evacuation of chronic subdural hematoma: A multicenter cohort study.

BACKGROUND: The decision to resume antithrombotic therapy after surgical evacuation of chronic subdural hematoma (CSDH) requires judicious weighing of the risk of bleeding against that of thromboembolism. This study aimed to investigate the impact of time to resumption of antithrombotic therapy on outcomes of patients after CSDH drainage. METHODS: Data were obtained retrospectively from three tertiary hospitals in Singapore from 2010 to 2017. Outcome measures analyzed were CSDH recurrence and any thromboembolic events. Logistic and Cox regression tests were used to identify associations between time to resumption and outcomes. RESULTS: A total of 621 patients underwent 761 CSDH surgeries. Preoperative antithrombotic therapy was used in 139 patients. 110 (79.1%) were on antiplatelets and 35 (25.2%) were on anticoagulants, with six patients (4.3%) being on both antiplatelet and anticoagulant therapy. Antithrombotic therapy was resumed in 84 patients (60.4%) after the surgery. Median time to resumption was 71 days (IQR 29 - 201). Recurrence requiring reoperation occurred in 15 patients (10.8%), of which 12 had recurrence before and three after resumption. Median time to recurrence was 35 days (IQR 27 - 47, range 4 - 82 days). Recurrence rates were similar between patients that were restarted on antithrombotic therapy before and after 14, 21, 28, 42, 56, 70 and 84 days, respectively. Thromboembolic events occurred in 12 patients (8.6%), of which five had the event prior to restarting antithrombosis. CONCLUSIONS: Time to antithrombotic resumption did not significantly affect CSDH recurrence. Early resumption of antithrombotic therapy can be safe for patients with a high thromboembolic risk.

Development of a prognostic scoring system to predict risk of reoperation for contralateral hematoma growth after unilateral evacuation of bilateral chronic subdural hematoma.

Bilateral chronic subdural hematoma (bCSDH) is frequently drained unilaterally when the contralateral CSDH is small and asymptomatic. However, reoperation rates for contralateral CSDH growth can be high. We aimed to develop a prognostic scoring system to guide the selection of suitable patients for unilateral drainage of bCSDH. Data were collected retrospectively across three tertiary hospitals from 2010 to 2017 on all consecutive bCSDH patients aged 21 or above. Predictors of reoperation were identified using multivariable logistic regression. A prognostic score was developed and internally validated. 240 bCSDH patients were analyzed. 98 (40.8%) underwent unilateral and 142 (59.2%) underwent bilateral evacuation. Clinical outcomes were comparable between the unilateral and bilateral evacuation groups. Within the unilateral evacuation group, 4 (4.1%) had a reoperation for contralateral CSDH growth. Reoperation for contralateral CSDH was predicted by preoperative use of anticoagulants (OR = 15.0, 95% CI: 1.49-169.15, p = 0.017). Complete resolution of contralateral CSDH was predicted by its preoperative maximum width, with a cut-off of 9 mm producing the highest sensitivity and specificity (OR = 4.17 for ≤9 mm, 95% CI: 1.54-11.11, p = 0.004). Using our prognostic score, reoperation rate for contralateral CSDH was 1.6%, 3.6%, 16.7%, and 50.0% in low-risk, moderate-risk, high-risk and very high-risk patients, respectively. With each increase of 1 in the prognostic score, patients were 4 times as likely to undergo reoperation for contralateral CSDH (OR = 3.98, 95% CI: 1.36-13.53, p = 0.013). Our proposed risk score may be used as an adjunct in clinical decision making for bCSDH patients undergoing unilateral evacuation.

Outcomes of Subdural Versus Subperiosteal Drain After Burr-Hole Evacuation of Chronic Subdural Hematoma: A Multicenter Cohort Study.

BACKGROUND: Although the use of a postoperative drain after burr-hole evacuation of chronic subdural hematoma (CSDH) is known to improve surgical outcomes, the superiority of subdural over subperiosteal drains has not been firmly established. Evidence comparing these 2 drain types is largely restricted to single-center series with limited numbers. Using a multicenter cohort study, we aimed to show noninferiority of subperiosteal drains vis-à-vis subdural drains after burr-hole evacuation of CSDH. METHODS: We performed a retrospective analysis of all consecutive patients with CSDH aged 21 years and older who had undergone burr-hole craniostomy across 3 tertiary hospitals from 2010 to 2017. Primary outcome measures included CSDH recurrence and modified Rankin Scale (mRS) score at 6 months. Outcomes of patients in the subdural and subperiosteal drain groups were analyzed and confounders were adjusted for using multivariate logistic regression. RESULTS: Of the 570 cases analyzed, 329 (57.7%) received a subdural drain and 241 (42.3%) received a subperiosteal drain. There was no significant difference between the 2 drain groups in CSDH recurrence (13.1% in the subdural group vs. 11.2% in the subperiosteal group; P = 0.502) or 6-month mRS score (27.2% with mRS 4-6 in the subdural group vs. 20.4% in the subperiosteal group; P = 0.188). Independent predictors of CSDH recurrence identified on multivariate analysis included premorbid mRS score 0-3 (P = 0.021), separated CSDH type on preoperative computed tomography scan (P = 0.002), and postoperative pneumocephalus of ≥15 mm (P = 0.005). CONCLUSIONS: Outcomes of subdural and subperiosteal drains after burr-hole craniostomy for CSDH are largely equivalent based on our findings.