A novel risk assessment model for venous thromboembolism after major thoracic surgery: a Chinese single-center study

Venous thromboembolism (VTE) is an insidious disease with significant morbidity and mortality. We conducted a retrospective single-center study on patients who underwent thoracic surgery and developed a novel VTE risk assessment model (RAM).

Patients who underwent thoracic surgery between July 2016 and December 2017 (n=533) at the Beijing Chao-Yang Hospital were enrolled in this study. None of the patients received any prophylaxis perioperatively. Lower limbs Doppler ultrasonography was performed before and after surgery for deep venous thrombosis (DVT) confirmation. Patients with new postoperative DVT, typical symptoms of pulmonary embolism (PE), or high Caprini score (≥9) underwent further computer tomography pulmonary angiography (CTPA) examination for PE. Caprini, Rogers, Padua, and Khorana RAM were used for all of the patients. A novel RAM of VTE, which we called Chao-Yang VTE RAM, was developed according to the logistic regression analysis.

The overall incidence of VTE after thoracic surgery was 8.4% (45 of 533). Among the 45 VTE patients, 86.7% have DVT and 13.3% have DVT + PE. Age ≥60 (OR 4.51, 95% CI: 2.09-9.71, P=0.000) has an independent risk factor for VTE. The areas under the receiver operating characteristic (ROC) curve of Caprini, Rogers, Padua, Khorana, and Chao-Yang models were 0.74 (P<0.0001), 0.52 (P=0.62), 0.69 (P<0.0001), 0.64 (P=0.0017), and 0.80 (P<0.0001), respectively. The VTE incidence in the low-, moderate-, and high-risk groups predicted with Chao-Yang scores was 1.3% (3 of 230), 8.4% (14 of 166), and 20.4% (28 of 137); these were 1.6% (3 of 192), 11.9% (38 of 318), and 17.4% (4 of 23), respectively, when using the Caprini criteria. The high-risk group had a significantly higher incidence than the low- and moderate-risk groups (P=0.000). Additionally, as the number of risk factors increased, the incidence of VTE increased from 1.2% to 50.0%.

The incidence of VTE in patients who underwent major thoracic surgery was high in our series. Based on a retrospective single-center population study, we developed a novel prediction model to identify patients receiving thoracic surgery with different risks for VTE events.