Machine learning models for predicting acute kidney injury after pediatric living donor liver transplantation in biliary atresia

Figure 1 Correlation heatmap of variables. A: Correlation heatmap of different variables; B: Heatmap of significantly different variables. Cr: Creatinine; LAC: Lactate; FFP: Fresh frozen plasma; ICU: Intensive care unit; PRS: Postreperfusion syndrome; AST: Aspartate aminotransferase; TB: Total bilirubin; AKI: Acute kidney injury; Ca²⁺: Calcium ion; Na⁺: Sodium ion.

Figure 2 Least absolute shrinkage and selection operator regression–selected features and their absolute coefficients. FFP: Fresh frozen plasma; AST: Aspartate aminotransferase; Cr: Creatinine; Ca²⁺: Calcium ion; LAC: Lactate.

Figure 3 Receiver operating characteristic and precision-recall curves of different models. A: Receiver operating characteristic curve; B: Precision-recall curve. ROC: Receiver operating characteristic; KNN: K-nearest neighbors; MLP: Multilayer perceptron; SVM: Support vector machine; AUC: Area under the curve; AP: Average precision.

Figure 4  Confusion matrix of the best prediction model.

Figure 5 SHapley Additive exPlanations analysis explanation diagram of the best model. A: The ranking of the importance of different features for acute kidney injury prediction; B: The diagram of the influence direction and intensity of different features; C: The prediction analysis of a single sample. Mean SHapley Additive exPlanations (SHAP) value is the SHAP mean/feature importance, base value is the baseline value, higher indicates higher risk, Lower indicates lower risk. Cr: Creatinine; AST: Aspartate aminotransferase; LAC: Lactate; Ca²⁺: Calcium ion; FFP: Fresh frozen plasma; SHAP: SHapley Additive exPlanations.

Figure 6 The influence of each independent factor on the prediction of acute kidney injury after living donor liver transplantation. A: The influence of pre- creatinine on acute kidney injury (AKI) prediction; B: The influence of post-aspartate aminotransferase on AKI prediction; C: The influence of anhepatic phase lactate level on AKI prediction; D: The influence of anhepatic phase calcium ions on AKI prediction; E: The influence of fresh frozen plasma infusion situation on AKI prediction; F: The influence of gender on AKI prediction. SHAP: SHapley Additive exPlanations; Cr: Creatinine; AST: Aspartate aminotransferase; LAC: Lactate; Ca²⁺: Calcium ion; FFP: Fresh frozen plasma.