Prediction of Symptomatic Venous Thromboembolism in Critically Ill Patients: The ICU-Venous Thromboembolism Score.

OBJECTIVES: To identify risk factors and develop a prediction score for in-hospital symptomatic venous thromboembolism in critically ill patients. DESIGN: Retrospective cohort study. SETTING: Henry Ford Health System, a five-hospital system including 18 ICUs. PATIENTS: We obtained data from the electronic medical record of all adult patients admitted to any ICU (total 264 beds) between January 2015 and March 2018. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Symptomatic venous thromboembolism was defined as deep vein thrombosis, pulmonary embolism, or both, diagnosed greater than 24 hours after ICU admission and confirmed by ultrasound, CT, or nuclear medicine imaging. A prediction score (the ICU-Venous Thromboembolism score) was derived from independent risk factors identified using multivariable logistic regression. Of 37,050 patients who met the eligibility criteria, 529 patients (1.4%) developed symptomatic venous thromboembolism. The ICU-Venous Thromboembolism score consists of six independent predictors: central venous catheterization (5 points), immobilization greater than or equal to 4 days (4 points), prior history of venous thromboembolism (4 points), mechanical ventilation (2 points), lowest hemoglobin during hospitalization greater than or equal to 9 g/dL (2 points), and platelet count at admission greater than 250,000/µL (1 point). Patients with a score of 0-8 (76% of the sample) had a low (0.3%) risk of venous thromboembolism; those with a score of 9-14 (22%) had an intermediate (3.6%) risk of venous thromboembolism (hazard ratio, 6.7; 95% CI, 5.3-8.4); and those with a score of 15-18 (2%) had a high (17.7%) risk of venous thromboembolism (hazard ratio, 28.1; 95% CI, 21.7-36.5). The overall C-statistic of the model was 0.87 (95% CI, 0.85-0.88). CONCLUSIONS: Clinically diagnosed symptomatic venous thromboembolism occurred in 1.4% of this large population of ICU patients with high adherence to chemoprophylaxis. Central venous catheterization and immobilization are potentially modifiable risk factors for venous thromboembolism. The ICU-Venous Thromboembolism score can identify patients at increased risk for venous thromboembolism.

Venous Thromboembolism in Neurocritical Care Patients.

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: 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.

PADUA score as a predictor for pulmonary embolism: a potential strategy for reducing unnecessary imaging.

An objective tool that is easy to integrate with an electronic medical record may help reduce unnecessary imaging for diagnosing a pulmonary embolism (PE). In this study, we assess the PADUA score in stratifying patients based on their risk of a PE. We reviewed charts of patients that underwent a computed tomography pulmonary angiogram (CT-PA) between January 2014 and September 2015 at our institution. Patient demographics including gender, age, race, and variables of the PADUA score were collected. The primary outcome was a positive CT-PA for a PE. Univariate and multivariate analysis was performed to derive predictors for a positive CT-PA. A receiver operator curve was calculated for the PADUA score and an optimal cutoff was calculated. Diagnostic test statistics were performed. Our study included 1067 patients. Of these, 185 (17.3%) had a PE. These patients tended to be older (64.3 SD 15.9 vs. 59.7 years SD 17.4, p < 0.01), have a higher proportion of Black patients (38.9% vs. 31.9%, p = 0.03), have a higher median [IQR] PADUA score (4.0 [3-6] vs. 3.0 [1-4], p < 0.01), and a higher rate of a DVT/PE history (30.3% vs. 5.2%, p < 0.01). Independent predictors included a DVT/PE history (OR: 7.65, 95% CI 4.89-12.0, p < 0.01), limited mobility (OR: 1.47, 95% CI 1.01-2.14, p = 0.046), and age 70 or greater (OR: 1.47, 95% CI 1.03-2.11, p = 0.03). The PADUA score had an AUC of 0.64 (95% CI 0.60-0.69, p = 0.046). The optimal cutoff was 4 and the sensitivity and specificity were 57.3% and 66.8%, respectively. The positive predictive and negative predictive values were 22.6% and 88.2%, respectively. The PADUA is a possible tool to stratify patients prior to performing a CT-PA. By using the score to guide management, we may be able to reduce unnecessary imaging through the implementation of the score in an EMR system. Further prospective research is warranted.