Performance Comparison of Pulmonary Risk Scoring Systems in Lung Resection

Abstract

Objective: To validate and compare the performance of different pulmonary risk scoring systems to predict postoperative pulmonary complications (PPCs) in lung resection surgery.

Design: Retrospective cohort study SETTING: A historic single-center cohort of lung resection surgeries PARTICIPANTS: Adult patients undergoing lung resection surgery under 1-lung ventilation.

Interventions: None.

Measurements and main results: The accuracy of the following pulmonary risk scoring systems were used to predict pulmonary complications: the ARISCAT (Assess respiratory RIsk in Surgical patients in CATalonia), the LAS VEGAS (Local Assessment of VEntilatory management during General Anesthesia for Surgery), the SPORC (Score for Prediction of Postoperative Respiratory Complications), and a recent thoracic-specific risk score, named CARDOT. Discrimination and calibration were assessed using the concordance (c) index and the intercept of LOESS (locally estimated scatterplot)-smoothed curves, respectively. Additional models were constructed that incorporated predicted postoperative forced expiratory volume (ppoFEV1) into each scoring system. Of the 2,104 patients undergoing lung surgery, 123 developed postoperative pulmonary complications (PPCs; 5.9%). All scoring systems had poor discriminatory power to predict PPCs (ARISCAT c-index 0.60, 95% confidence interval [CI] 0.55-0.65; LAS VEGAS c-index 0.68, 95% CI 0.63-0.73; SPORC c-index 0.63, 95% CI 0.59-0.68; CARDOT c-index 0.64, 95% CI 0.58-0.70), but the inclusion of ppoFEV1 slightly improved the performance of LAS VEGAS (c-index 0.70, 95% CI 0.66-0.75) and CARDOT (c-index 0.68, 95% CI 0.62-0.73). Analysis of calibration showed a slight overestimation when using ARISCAT (intercept -0.28) and LAS VEGAS (intercept -0.27).

Conclusions: None of the scoring systems appeared to have adequate discriminatory power to predict PPCs among patients undergoing lung resection. An alternative risk score is necessary to better predict patients at risk of PPCs after thoracic surgery.

Keywords: hypoxemia; lung surgery; mechanical ventilation; postoperative pulmonary complications; surgery.