Reduction of thromboembolic events in meningioma surgery: a cohort study of 724 consecutive patients

Abstract

Background: Meningiomas are associated with the highest postoperative rate of venous thromboembolic events (VTE) among all intracranial tumors. The aim of this study is to compare two entirely different VTE prophylaxis regimens in 724 consecutive patients undergoing meningioma surgery.

Methods: Two cohorts at a single institution treated with different regimens to prevent VTE were reviewed retrospectively. Cohort A (n = 482; 314 females, mean age 57 years, range: 11-87 years) received our institutional regimen during the years 1999-2006, consisting of low-molecular-weight heparin (LMWH) and compression stockings. For cohort B (n = 242; 163 females, mean age 56.8 years, range: 16-90 years), during the years 2008-2010, the management included intraoperative 10°-20° leg elevation with intermittent pneumatic compression (IPC), heparin and LMWH administration. We compared the incidence of the endpoints pulmonary embolism (PE), deep venous thrombosis (DVT), hemorrhage and death, taking into account several known associated risk factors.

Results: For all endpoints, we observed a more favorable outcome with the new regimen. The difference in incidence of PEs (cohort A: 38/482, 8%; cohort B: 6/242, 2.5%) reached statistical significance (p = 0.002). In general, patients with skull base meningiomas had a higher risk for PE (OR 2.77). Regarding VTE prophylaxis, an adjusted subgroup analysis suggests that the new regimen is particularly beneficial for patients with skull base meningiomas.

Conclusions: We recommend perioperative prophylaxis using a management composed of intraoperative leg-elevation, IPC, early heparin administration and LMWH to reduce the risk for PE.

Figure 1. Incidence of the primary endpoints of both applied managements from admission until three months follow-up.

The endpoint “PE and DVT” showed concurrent PE and DVT. “Overall complication” shows the appearance of any of the primary endpoints PE, DVT, hemorrhage or death. Bars are in % of patients in each management.

Figure 2. BMI with incidence of meningioma and PE.

The legend for BMI is on the left side of the panel. The number of PE corresponding to each age-group and the incidence of meningioma in percent is quantified on the right side. All three factors increased with age until the sixth decade and decreased with advanced age (>70 years).

Figure 3. (A) Average BMI of study subjects and average national BMI.

The registered BMI of subjects with a meningioma in the years 1999–2010 (n = 574) was higher than the national BMI. Shown are the proportions in weight categories based on BMI. (B) Incidence of PE assigned to BMI-categories. The distribution of patients with PE, depicted for BMI categories of the two cohorts separately.

Figure 4. Comparison between meningioma locations.

Cases with a skull base location (A) had a higher risk for PE (OR: 2.77 with 95% CI 1.15 to 7.07; p = 0.0096) compared to subjects with non-skull base meningioma. (B). The difference of odds ratio (OR) estimates between skull base and non-skull base meningioma is significant for DVT (p = 0.02) and overall complication (p = 0.05).

Figure 5. PE associated factors.

The comparison of cases with PE and cases without PE showed that PE is significantly associated with skull base meningioma (p = 0.01), prolonged hospital stay (p = 0.01 difference = 2.87 days) and higher BMI (p = 0.03 difference = 4.05 kg/m²).