Introduction: Surgical resection of meningiomas has been associated with the highest rates of venous thromboembolic events (VTE) as compared with all other intracranial tumors. The underlying pathophysiological mechanism for this tumor-specific finding remains unclear. There is a paucity of data regarding the clinical complications and comorbidities associated with this cohort. The purpose of this study was to determine the risk factors for VTE in a large cohort of patients with intracranial meningiomas undergoing surgery.

Methods: This retrospective analysis utilized discharge data from the National Inpatient Sample (NIS) from 2002-2010. Patient demographics, comorbidities, length of stay, hospital charges, and postoperative complications were compared between patients with and without VTE. Cross-tabulation, Pearson’s chi-square tests, Fischer’s exact test, and independent 2-tailed t tests were used where appropriate. Binary logistic regression was performed with various postoperative complications as the dependent variable.

Results: Of 20,259 patients, 426 (2.1%) experienced a VTE. Compared to the non-VTE cohort, patients that experienced a VTE were older (62.7±13.7 vs. 57.2±14.7; p < 0.001), more commonly male (38.0% vs 30.1%; p = 0.001), had longer hospitalizations (18.8 vs 6.6 days; p < 0.001), and incurred significantly greater hospital charges ($195,837 vs $74,434; p < 0.001). The VTE cohort also had higher comorbidity rates, including congestive heart failure (5.6% vs 2.2%, p < 0.001), hypertension (50.2% vs 45.1%, p < 0.045), diabetes mellitus (20.4% vs 15.7%, p < 0.010), peripheral vascular disorders (2.8% vs 1.2%, p < 0.003), and preexisting coagulopathies (11.7% vs 2.0%; p < 0.001). VTE patients experienced significantly higher rates of acute postoperative complications including shock, hemorrhage, wound dehiscence, infection, intracerebral hemorrhage, hemiparesis/hemiplegia, stroke, and death during admission.

Conclusions: Occurrence of VTE in patients undergoing meningioma resection portends greater hospital charges, longer lengths of admission, increased postoperative complications and mortality. Neurosurgeons should be aware of this complication risk when treating meningioma patients.

Patient Care: Venous thromboembolic events (VTE), which include deep vein thrombosis (DVT) and pulmonary embolisms (PE), represent the most common complication observed in patients undergoing meningioma surgery. Development of postoperative VTE has shown to be fatal in over one third of subjects, an aggravating statistic that alone has pushed the medical field to identify potential risk factors associated with this complication. While ample data already exists on specific risks and complications inherent to meningioma surgery, to date little is known about patient-specific factors and their influence on the development and outcome of post-operative VTE. The current study utilizes the National Inpatient Sample (NIS) database, a multi-institutional, population-based resource, to report the prevalence, impact and risk factors of VTE following intracranial meningioma surgery.

Learning Objectives: 1. To report the prevalence, impact and risk factors of VTE following intracranial meningioma surgery 2. To learn about patient-specific factors and their influence on the development and outcome of post-operative VTE and promote further investigation and wariness of the physician when treating surgical candidates of meningioma. 3.To illustrate the statistical power and external validity obtained when utilizing multi-institutional, population-based resources to investigate of uncommon disorders.

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