Construction and validation of a nomogram model for predicting delayed wound healing after abdominal surgery

ZHAO Qiang; CAO Songmei; BAI Suping

doi:10.3969/j.issn.1674-3806.2025.04.19

Abstract：Objective To construct and validate a nomogram model for predicting delayed wound healing after abdominal surgery.Methods The clinical data of 635 patients who underwent abdominal surgery in Affiliated Hospital of Jiangsu University from August 1,2023 to August 1,2024 were retrospectively analyzed.All the patients were divided into a training set(444 cases)and a validation set(191 cases)at a ratio of 7∶3.According to wound healing,the patients in the training set were divided into normal healing group(healing time ≤2 weeks,322 cases)and delayed healing group(healing time＞2 weeks,122 cases).The independent variables were screened by LASSO regression.The influencing factors of delayed wound healing after abdominal surgery were analyzed by multivariate logistic regression,and a nomogram prediction model was established.The differentiation,calibration,goodness of fit and clinical applicability of the model were evaluated by using receiver operating characteristic(ROC)curve,calibration curve,Hosmer-Lemeshow goodness-of-fit test and clinical decision curve analysis,respectively.Results Eight independent variables which were screened out by LASSO regression were hemoglobin,total protein,wound area,history of diabetes,presence or absence of infection within 2 weeks after surgery,presence or absence of chemotherapy within 3 months before surgery,history of smoking and type of surgery.The results of multivariate logistic regression analysis showed that larger wound area,history of diabetes,infection within 2 weeks after surgery,chemotherapy within 3 months before surgery,and history of smoking were independent risk factors for delayed wound healing after abdominal surgery(P＜0.05).Higher hemoglobin level and higher total protein were independent protective factors for delayed wound healing after abdominal surgery(P＜0.05).A nomogram model for predicting delayed wound healing after abdominal surgery was constructed based on 7 influencing factors.The results of ROC curve analysis showed that area under the curve(AUC)(95％CI)of the model in the training set was 0.950(0.926-0.975),with a sensitivity of 92.60％and a specificity of 87.90％.The results of ROC curve analysis showed that area under the curve(AUC)(95％CI)of the model in the validation set was 0.945(0.900-0.990),with a sensitivity of 96.00％and a specificity of 87.20％.The results of ROC curve analysis showed good differentiation.The calibration curve analysis showed that the probability of the model predicting the risk of delayed wound healing after abdominal surgery was basically consistent with the actual probability,which had a good calibration.The results of Hosmer-Lemeshow goodness-of-fit test(the training set:x2=4.805,P=0.778;the validation set:x2=0.402,P=0.818)proved that the model had satisfactory goodness of fit.The results of clinical decision curve analysis showed that the model had good applicability in clinic.Conclusion The nomogram model constructed based on 7 influencing factors including hemoglobin,total protein,wound area,history of diabetes,presence or absence of infection within 2 weeks after surgery,presence or absence of chemotherapy within 3 months before surgery and history of smoking has a relatively good value in predicting delayed wound healing after abdominal surgery.