Venous Thromboembolism Prophylaxis in Meningioma Surgery: A Population-Based Comparative Effectiveness Study of Routine Mechanical Prophylaxis with or without Preoperative Low-Molecular-Weight Heparin

OBJECTIVES: Venous thromboembolism (VTE) is a serious complication after intracranial meningioma surgery. To what extent systemic prophylaxis with pharmacotherapy is beneficial with respect to VTE risk, or associated with increased risk of bleeding and postoperative hemorrhage, remains debated. The current study aimed to clarify the risk/benefit ratio of prophylactic pharmacotherapy initiated the evening before craniotomy for meningioma. METHODS: In a Scandinavian population-based cohort, we conducted a retrospective review of 979 operations for intracranial meningioma between 2007 and 2013 at 3 neurosurgical centers with population-based referral. We compared 2 different treatment strategies analyzing frequencies of VTE and proportions of postoperative intracranial hematomas requiring surgery or intensified subsequent observation or care (intensive care unit or other intensified observation or treatment). One neurosurgical center favored preoperative prophylaxis with low-molecular-weight heparin (LMWH) (LMWH routine group) in addition to mechanical prophylaxis, and 2 centers favored mechanical prophylaxis with LMWH only given as needed in cases of delayed mobilization (LMWH as needed group). RESULTS: In the LMWH routine group, VTE was diagnosed after 24/626 operations (3.9%), and VTE was diagnosed after 11/353 (3.1%) operations in the LMWH as needed group (P = 0.56). Clinically relevant postoperative hematomas occurred after 57/626 operations (9.1%) in the LMWH routine group compared with 23/353 (6.5%) in the LMWH as needed group (P = 0.16). Surgically evacuated postoperative hematomas occurred after 19/626 operations (3.0%) in the LMWH routine group compared with 8/353 operations (2.3%) in the LMWH as needed group (P = 0.26). CONCLUSIONS: There is no benefit of routine preoperative LMWH starting before intracranial meningioma surgery. Neither could we for primary outcomes detect a significant increase in clinically relevant postoperative hematomas secondary to this regimen. We suggest that as needed perioperative administration of LMWH, reserved for patients with excess risk because of delayed mobilization, is effective and also appears to be the safest strategy.