The risks, timing and safety of anticoagulation therapy following intracranial surgery: a systematic review and meta-analysis.

The timing, safety, and efficacy of prophylactic anticoagulation following craniotomy are well established in the literature. However, anticoagulation therapy (ACT) remains a controversial topic, and the literature on the subject is extremely scarce, preventing robust conclusions about its risks and safety. Our study aims to identify the risks and the best time to start ACT following intracranial surgery. A systematic review was conducted using Embase, PubMed, and Cochrane databases. The primary outcome was intracranial hemorrhage (ICH). Secondary outcomes were mortality and surgical reintervention. Statistical analyses were performed using RStudio 2024.09.0 + 375. Sensitivity analysis was performed using subgroup analysis, and leave-one-out test. The risk of bias was assessed using ROBINS-I. Of 800 potential articles, seven met our inclusion criteria, encompassing a total of 304 patients. The mean age was 56 years and 46% of the patients were male. The main reasons for intracranial surgery were intracranial tumor (48%) and vascular surgery (18%). Intra-axial surgery and starting ACT before the first 48 h were factors associated with higher odds of ICH. The mean interval between the start of ACT and surgery was 5 days, and the mean time from initiation of ACT to ICH was 6.8 days. The ICH rate due to ACT use was 7.96% (95% CI 1.90%-16.86%) between 0 and 30 days after surgery, 11.61% (95% CI 0.98%-29.09%) between 0 and 10 days, and 9.15% (95% CI 3.03%-17.47%) between 10 and 30 days. The mortality rate due to ICH secondary to ACT was 0.70% (95% CI 0.00%-3.22%). The surgical reintervention rate due to ICH secondary to ACT was 1.06% (95% CI 0.00%-5.36%). Our results suggest that the risk of ICH and mortality due to early ACT (< 10 days) following intracranial surgery might be overestimated, and this management could be a viable strategy, especially if started 48 h after surgery and in patients who have undergone extra-axial surgery. Nevertheless, it is important to consider the various limitations that may impact these observations, and controlled prospective studies are needed to provide more robust conclusions. Clinical trial number: Not applicable.