A Thoracic Surgery-Specific Risk Assessment Model to Prevent Perioperative Venous Thromboembolism

The risk of venous thromboembolism (VTE) in patients undergoing resection in the setting of lung cancer represents a major challenge to improving postoperative outcomes. The Caprini risk assessment model has been validated in general surgery to determine a role for extended chemoprophylaxis to reduce VTE events. Our goal was to simplify this burdensome model for the unique needs of this thoracic surgical population to better guide anticoagulation decision-making.

Patients who underwent a resection for lung malignant neoplasm at our institution between June 2005 and June 2013 with available 60-day postoperative follow-up data were evaluated. Exclusion criteria were long-term anticoagulation, inferior vena cava filter, missing data, and loss to follow-up. Twelve selected risk factors were analyzed for each patient by logistic regression with stepwise inclusion to model 60-day VTE incidence.

There were 225 patients eligible for inclusion, and a VTE incidence of 5.8% was observed. We generated a 5-variable model with predictive ability for VTE occurrence similar to that of the Caprini risk assessment model (P = .29). Weighting of sex, age, history of VTE, surgical approach, and duration of procedure provides a low-risk or high-risk composite score with 56% sensitivity and 77% specificity.

In this effort to model VTE incidence on the basis of a limited set of clinical risk factors, we demonstrated efficacy of retrospectively scoring patients with just 5 data points in anticipating risk of postoperative VTE. These high-risk surgical patients can be readily identified in the preoperative period to benefit from extended postoperative prophylaxis.