External validation of the modified Thoracoscore in a new thoracic surgery program: prediction of in-hospital mortality

Abstract
Informed consent prior to any surgical intervention should include in-hospital survival estimation after the procedure performed. The recently developed Thoracoscore predicts well the postoperative mortality possibility. The purpose of our study was to test the modified Thoracoscore performance in our new thoracic program. One hundred and fifty-five consecutive patients underwent thoracic surgery procedure within two years. The procedures performed were: 62 lung resections, 10 open tumor biopsies, 21 neck and mediastinal procedures, 33 chest wall and pleural procedures, 8 tracheal procedures, 3 esophageal procedures, 13 minor cardiac procedures, and 5 chest trauma cases. The modified Thoracoscore was calculated based on the following variables: age, gender, priority of the procedure, malignancy, type of procedure, Zubrod score, ASA class, and number of co-morbidities. The observed mortality was 5.2% (eight deaths) while the predicted one based on the modified Thoracoscore was 4.9%. The scoring system we used had excellent discriminatory ability with a C statistic (0.95, 95% CIs 0.91–0.99). The Hosmer–Lemeshow goodness-of-fit was not statistically significant (P=0.82), indicating acceptable calibration of the model for the present series. The modified Thoracoscore's ability to predict postoperative survival in the whole context of thoracic surgery performs well in our program. Application of any risk scoring system requires external validation and provides comparison of the actual outcomes with other programs.