Development of a nomogram to predict prolonged drainage time after cardiac surgery

作者：Li, Hongmu; Lin, Xifeng; Tao, Jun; Zou, Rongjun; Yang, Songran^*; Hua, Ping^*

来源：International Journal of Clinical and Experimental Pathology, 2017, 10(6): 6635-6644.

• Cardiac surgery
• postoperative drainage time
• nomogram

Background: Drainage tube indwelling after cardiac surgery is very important, and an accurate prediction of prolonged postoperative drainage risk can help surgeons choose a better treatment strategy. We aimed to develop a nomogram to predict the risk of prolonged drainage time after cardiac surgery. Materials and methods: We retrospectively collected data of 246 consecutive patients who underwent open cardiac surgery in Sun Yat-sen Memorial Hospital affiliated to Sun Yat-sen University between 1 January 2014 and 1 January 2016. Patients who underwent surgery at an earlier period comprised the training cohort (n=152) for nomogram development; those who underwent surgery thereafter comprised the validation cohort (n=94) to confirm the model's performance. Multivariate logistic regression was used to identify independent risk factors associated with postoperative drainage time, which were later incorporated into the nomogram. Results: Univariate analysis found that sex, cardiopulmonary bypass time (CPB time), history of smoking, white blood cell count (WBC), preoperative creatinine (Cr), left atrial diameter (LAD), ejection fraction (EF) and prothrombin time-international normalized ratio (PT-INR) were significant predictors of postoperative drainage time. The nomogram's C-index was 0.78 in the training cohort and 0.66 in the validation cohort. The sensitivity of the nomogram was 80.0% (95% CI, 69.2-95) and 80.65% (95% CI, 62.5-92.5) in the training and validation cohorts, respectively. The area under the ROC analysis was 0.78 (95% CI, 0.71-0.86) and 0.66 (95% CI, 0.54-0.77) in the training and validation cohorts, respectively. Positive odds ratios were 2.43 (95% CI, 1.7-3.4) and 0.52 (95% CI, 1.1-2.0), and negative odds ratio were 0.30 (95% CI, 0.2-0.5) and 0.41 (95% CI, 0.2-0.9) in the training and validation cohorts, respectively. Conclusion: The nomogram achieved an optimal prediction of the risk of prolonged drainage time after cardiac surgery, which may be useful to make appropriate therapeutic choices.

• 出版日期2017
• 单位中山大学