A Prospective Observational Study to Investigate the Predictive Value of Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) Risk Score for Predicting Postoperative Pulmonary Complications in Patients Undergoing Major Elective Open Abdominal Cancer Surgeries

Background and aims: Postoperative pulmonary complications (PPCs) are common after upper abdominal cancer surgery. Early identification of patients at high risk for PPCs allows implementation of targeted perioperative preventive strategies. The Assess Respiratory Risk in Surgical Patients in Catalonia (ARISCAT) score is a validated preoperative risk assessment tool for predicting PPCs. This study aimed to evaluate the performance of the ARISCAT score in this population and, following the primary analysis, to explore the possibility of developing and internally evaluating a modified ARISCAT (mARISCAT) score. Patients and methods: This prospective, two-center observational study included patients undergoing elective, open, upper abdominal cancer surgery. The primary analysis evaluated the incidence of PPCs and the predictive performance of the ARISCAT score. Following completion of the primary analyses, a distinct exploratory post hoc analysis was undertaken to evaluate the predictive ability of the mARISCAT score. Logistic regression identified predictors of PPCs, which were incorporated into the proposed mARISCAT score. Results: Postoperative pulmonary complications occurred in 113 of 494 patients (22.9%). In the primary analysis, the ARISCAT score showed limited discriminatory ability for predicting PPCs [area under the receiver operating characteristic curve (AUROC) = 0.55]. In exploratory derivation analysis, operative duration ≥355 minutes [odds ratio (OR) = 3.76, 95% confidence interval (CI) = 1.82–7.76], intraoperative transfusion ≥257 mL (OR = 3.24, 95% CI = 1.80–5.86), and positive intraoperative fluid balance ≥2,225 mL (OR = 1.88, 95% CI = 1.01–3.48) were independently associated with PPCs. The proposed mARISCAT score demonstrated improved discrimination, with an AUROC of 0.757 (95% CI = 0.700–0.815) in the derivation cohort and 0.701 (95% CI = 0.614–0.789) in the validation cohort during internal validation. Logistic calibration yielded a slope of 1.00 and an intercept of 0.00. The Hosmer–Lemeshow test was non-significant (χ² = 5.33, p = 0.620). Conclusion: The primary analysis demonstrated that the ARISCAT score has limited predictive accuracy for PPCs in patients undergoing major elective upper abdominal cancer surgery. The post hoc mARISCAT score requires intraoperative variables and is therefore not a preoperative score; it showed moderate discrimination during split-sample internal evaluation. However, as the model was developed through an exploratory post hoc analysis and has undergone internal validation only, prospective external multicenter validation is essential before clinical application.