An explainable machine learning model to predict early and late acute kidney injury after major hepatectomy.

BACKGROUND: Risk assessment models for acute kidney injury (AKI) after major hepatectomy that differentiate between early and late AKI are lacking. This retrospective study aimed to create a model predicting AKI through machine learning and identify features that contribute to the development of early and late AKI. METHODS: Patients that underwent major hepatectomy were categorized into the No-AKI, Early-AKI (within 48 h) or Late-AKI group (between 48 h and 7 days). Modeling was done with 20 perioperative features and the performance of prediction models were measured by the area under the receiver operating characteristic curve (AUROCC). Shapley Additive Explanation (SHAP) values were utilized to explain the outcome of the prediction model. RESULTS: Of the 1383 patients included in this study, 1229, 110 and 44 patients were categorized into the No-AKI, Early-AKI and Late-AKI group, respectively. The CatBoost classifier exhibited the greatest AUROCC of 0.758 (95% CI: 0.671-0.847) and was found to differentiate well between Early and Late-AKI. We identified different perioperative features for predicting each outcome and found 1-year mortality to be greater for Early-AKI. CONCLUSIONS: Our results suggest that risk factors are different for Early and Late-AKI after major hepatectomy, and 1-year mortality is greater for Early-AKI.

Multiple Myelographic Defects at Lumbosacral Region and Appropriate Area of Operation / 대한정형외과학회잡지

When the multiple myelographic defects at lumbosacral region are noted, the prudential effort for decision of appropriate area of surgical decompression would be needed. Fifty four patients who had been treated surgically for the deseases, such as HNP and spinal stenosis, from March in 1982 to Feb. In 1987 at Department of Orthopecdic Surgery, Soonchunhyang University Hospital, were analyzed in order to define the etiology, the level of the defect, indication for the operation and to assess the results of each level which had been operated. The results of the study were as follows. 1. The number of patients, which the multiple indentations were noted in the myelogrsphy, was 54 cases, 29 spinal stenosis, 15 HNP and 10 mixed types. 2. The most common defect levels in myelography were L3-4 snd L4-5, which were 19 cases (35.2%), the next levels were L4-5 and L5S1, which were 16 cases(29.6%), then L3-4, L4-5 and L5S1 were 7 cases(13%) and the other levels were 12 cases(22.2%). 3. The decision for the sppropriste operation area had not be done following to the size of the myelographic defect, but the clinical symptoms and physicsl exsminations. 4. The results were classified ss excellent or good in 79.7%, which was 80% at two levels snd 79.5% at one level. 5. The operation levels could be decressed for the reducing the spinal instability, operation time and possibility of the dangerous conditions and promotion of early restoration and, ambulation, if the severe differences between the results of one and two operation levels were not seen.

Slipped Capital Femoral Epiphysis: Reports of Two Cases / 대한정형외과학회잡지

The slipped capital femoral epiphysis is characterized by a growth disturbance of the capital physi. resulting in weakening of this structure and a subsequent displacement of the femoral head on the fe moral neck. It is a rare entity in Korea and only six cases have been reported so far1-5). One of ou cases was a bilateral mild acute slips in 13 yearold boy which were treated by Hagie pinning. Th other case, a 17 year-old boy, who suffered from a moderate acute on chronic slip in his left hip an showed a typical Pistol grip deformity. He was treated by gentle closed rcduction and Knowles pi fixation with good result.