Therapeutic anticoagulation for venous thromboembolism after recent brain surgery: Evaluating the risk of intracranial hemorrhage.

ABSTRACT

OBJECTIVE: Venous thromboembolism (VTE) is particularly prevalent in neurosurgical patients. A major dilemma arises when a patient needs to be treated with therapeutic anticoagulation during the early days after brain surgery due to the concern of intracranial hemorrhage (ICH). There is still a lack of studies regarding the optimal time to start therapeutic anticoagulation and risk assessment of ICH in this setting. This study aims to assess the risk of ICH for patients with venous thromboembolism treated with therapeutic anticoagulation started within the first 30 days after intracranial neurosurgical procedure. PATIENTS AND METHODS: This study was an analytical observational research based on a retrospective record review of VTE patients submitted to therapeutic anticoagulation started within the first 30 days after intracranial neurosurgical procedure at Paulo Niemeyer State Brain Institute, from September 2013 to February 2020. Patients' clinical and surgical data, anticoagulation drug therapy, time interval between surgery and start of therapeutic anticoagulation, bleeding complications and hemorrhage-related deaths were some of variables evaluated. A p value < 0.05 was considered statistically significant. RESULTS: A series of 53 consecutive patients and 54 intracranial neurosurgical procedures met the criteria. Twenty-nine (53.7 %) patients were treated with warfarin, 21 (38.9 %) with new oral anticoagulant (NOAC) and 4 (7.4 %) only with enoxaparin. VTE diagnosis between the postoperative days 0 and 4 was statistically associated with a delay in starting therapeutic anticoagulation of more than two days (p < 0.001). The frequency of bleeding complication was statistically significant higher in patients treated with warfarin (p = 0.03). Although with no statistical significance, there were a higher rate of ICH in patients receiving warfarin (13.8 % vs. 0% in NOAC group, p = 0.13). There was no statistical difference about ICH incidence between the postoperative intervals from 2nd to 7th, 8th to 14th, 15th to 21 st and 22th to 29th days (p = 0.35). Hemorrhage-related mortality rate was 3.7 %. CONCLUSION: ICH was not statistically associated with the timing of therapeutic anticoagulation after brain surgery between the 2nd and 29th postoperative days, which may encourage the strategy of early treatment considering the life-threatening potential of VTE. However, the risk of ICH should not be ignored in the setting of warfarin use, which had a remarkable incidence of 13.8 %. Warfarin must be used cautiously, especially in high-grade gliomas.