A novel nomogram for predicting the decision to delayed extubation after thoracoscopic lung cancer surgery

OBJECTIVE: Delayed extubation was commonly associated with increased adverse outcomes. This study aimed to explore the incidence and predictors and to construct a nomogram for delayed extubation after thoracoscopic lung cancer surgery. METHODS: We reviewed medical records of 8716 consecutive patients undergoing this surgical treatment from January 2016 to December 2017. Using potential predictors to develop a nomogram and using a bootstrap-resampling approach to conduct internal validation. For external validation, we additionally pooled 3676 consecutive patients who underwent this procedure between January 2018 and June 2018. Extubation performed outside the operating room was defined as delayed extubation. RESULTS: The rate of delayed extubation was 1.60%. Multivariate analysis identified age, BMI, FEV(1)/FVC, lymph nodes calcification, thoracic paravertebral blockade (TPVB) usage, intraoperative transfusion, operative time and operation later than 6 p.m. as independent predictors for delayed extubation. Using these eight candidates to develop a nomogram, with a concordance statistic (C-statistic) value of 0.798 and good calibration. After internal validation, similarly good calibration and discrimination (C-statistic, 0.789; 95%CI, 0.748 to 0.830) were observed. The decision curve analysis (DCA) indicated the positive net benefit with the threshold risk range of 0 to 30%. Goodness-of-fit test and discrimination in the external validation were 0.113 and 0.785, respectively. CONCLUSION: The proposed nomogram can reliably identify patients at high risk for the decision to delayed extubation after thoracoscopic lung cancer surgery. Optimizing four modifiable factors including BMI, FEV(1)/FVC, TPVB usage, and operation later than 6 p.m. may reduce the risk of delayed extubation. KEY MESSAGES: This study identified eight independent predictors for delayed extubation, among which lymph node calcification and anaesthesia type were not commonly reported. Using these eight candidates to develop a nomogram, we could reliably identify high-risk patients for the decision to delayed extubation. Optimizing four modifiable factors, including BMI, FEV(1)/FVC, TPVB usage, and operation later than 6 p.m. may reduce the risk of delayed extubation.