Venous Thromboembolism in Neurocritical Care Patients

Venous thromboembolism (VTE) is a potentially life-threatening complication among critically ill patients. Neurocritical care patients are presumed to be at high risk for VTE; however, data regarding risk factors in this population are limited. We designed this study to evaluate the frequency, risk factors, and clinical impact of VTE in neurocritical care patients.

We obtained data from the electronic medical record of all adult patients admitted to neurological intensive care unit (NICU) at Henry Ford Hospital between January 2015 and March 2018. Venous thromboembolism was defined as deep vein thrombosis, pulmonary embolism, or both diagnosed by Doppler, chest computed tomography (CT) angiography or ventilation-perfusion scan >24 hours after admission. Patients with ICU length of stay <24 hours or who received therapeutic anticoagulants or were diagnosed with VTE within 24 hours of admission were excluded.

Among 2188 consecutive NICU patients, 63 (2.9%) developed VTE. Prophylactic anticoagulant use was similar in patients with and without VTE (95% vs 92%; P = .482). Venous thromboembolism was associated with higher mortality (24% vs 13%, P = .019), and longer ICU (12 [interquartile range, IQR 5-23] vs 3 [IQR 2-8] days, P < .001) and hospital (22 [IQR 15-36] vs 8 [IQR 5-15] days, P < .001) length of stay. In a multivariable analysis, potentially modifiable predictors of VTE included central venous catheterization (odds ratio [OR] 3.01; 95% confidence interval [CI], 1.69-5.38; P < .001) and longer duration of immobilization (Braden activity score <3, OR 1.07 per day; 95% CI, 1.05-1.09; P < .001). Nonmodifiable predictors included higher International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) scores (which accounts for age >60, prior VTE, cancer and thrombophilia; OR 1.66; 95% CI, 1.40-1.97; P < .001) and body mass index (OR 1.05; 95% CI, 1.01-1.08; P = .007).

Despite chemoprophylaxis, VTE still occurred in 2.9% of neurocritical care patients. Longer duration of immobilization and central venous catheterization are potentially modifiable risk factors for VTE in critically ill neurological patients.