Development and validation of a predictive scoring system for excessive intraoperative blood loss in orthognathic surgery.

Abstract

Risk stratification for excessive bleeding prior to orthognathic surgery is necessary for optimizing patient safety and enhancing postoperative recovery. The aim of this study was to develop and validate a simplified scoring system for predicting excessive intraoperative blood loss (IBL) during orthognathic surgery. This retrospective cohort study included 361 patients who underwent orthognathic surgery. Factors related to excessive IBL were analysed. The candidate predictors for excessive IBL were determined by logistic regression analysis. The performance of the model was assessed through its discrimination ability and a calibration plot. Internal validation was done by bootstrap resampling technique. The regression coefficients were transformed into a scoring system. Excessive IBL occurred in 32.7% of patients (118/361). The predictive scoring system included three predictors: body mass index (score 0, 1.5, 2: overweight, normal weight, underweight), systolic blood pressure (score 0, 1: <130, ≥130 mmHg), and operative time (score 0, 2.5: ≤4, >4 h). The area under the receiver operating characteristic curve (AUROC) for discrimination ability was 0.828 (internal validation: C-statistic 0.812). Risk was then classified as low (0-2.5 points) or high (3-5.5 points). The prognostic ability of this simplified scoring system was found to be clinically acceptable for predicting excessive IBL during orthognathic surgery.