Development of nomogram predicting postoperative blood loss among pediatric patients following corrective operation of tetralogy of Fallot / 中国胸心血管外科临床杂志

ABSTRACT

@#Objective    To identify the risk factors of postoperative blood loss among pediatric patients following corrective operation of tetralogy of Fallot (TOF) and to develop nomogram predicting the risk of postoperative blood loss. Methods    A retrospective case-control study was conducted in pediatric TOF patients who underwent corrective operation in our hospital from November 2018 to June 2019. And the clinical data from each enrolled patient were gathered and analyzed. Clinically significant postoperative blood loss was defined as drainage volume from chest tube ≥ 16 mL/kg during the first 24 h after surgery, which corresponded to the 75th percentile of the blood loss in our population. The primary outcome was to determine the independent predictors of postoperative blood loss by the least absolute shrinkage and selection operator (LASSO) regression, univariate and multivariate logistic regression analysis. On the basis of the independent predictors of postoperative bleeding, nomogram was developed and its discrimination and calibration were estimated. Results    A total of 105 children were selected (67 males and 38 females aged 3-72 months). The drainage volume from chest tube in the bleeding group was significantly higher than that in the non-bleeding group during the first 24 h (P<0.000 1). Multivariate logistic regression analysis showed that low body weight (OR=0.538, 95%CI 0.369-0.787, P=0.001), high preoperative hemoglobin concentration (OR=1.036, 95%CI 1.008-1.066, P=0.013) and prolonged intraoperative aortic cross clamp time (OR=1.022, 95%CI 1.000-1.044, P=0.048) were independent risk factors for postoperative blood loss. In the internal validation, the model displayed good discrimination with a C-index of 0.835 (95%CI 0.745-0.926) and high quality of calibration plots in nomogram models was noticed. Conclusion    The nomogram demonstrated good discrimination and calibration in estimating the risk of postoperative blood loss among pediatric patients following corrective operation of TOF.