飯塚 悠祐

BACKGROUND: One-lung ventilation (OLV) is an essential technique in thoracic surgery, and double-lumen endobronchial tubes (DLTs) are commonly used. While right-sided DLTs are useful in specific situations, few studies have investigated the prevalence of their use. This study aimed to investigate the current practice of OLV and right-sided DLT usage among anesthesiologists in Japan. METHODS: A nationwide cross-sectional survey was conducted in September 2024, targeting 1444 hospitals certified by the Japanese Society of Anesthesiologists. Questionnaires were mailed to anesthesiology departments, inquiring about OLV practices, right-sided DLT usage, challenges, and desired improvements. Responses were collected via postal mail or web, and data were analyzed using descriptive statistics and Chi-square tests. RESULTS: A total of 768 institutions responded (response rate: 53.2%). Among 761 valid responses, 74.9% performed OLV, and DLTs were the most frequently used device (94.7%). Approximately half (45.8%) of the institutions performing OLV reported never using right-sided DLTs. Frequently recognized challenges included insertion difficulty, positioning difficulty, and unfamiliarity, and 42.1% of institutions expressed a willingness to increase the use of right-sided DLTs if these challenges were resolved. Institutions with a higher annual volume of OLV cases tended to use right-sided DLTs more frequently, but the proportion of institutions unfamiliar with right-sided DLTs was not associated with the number of OLV cases performed. CONCLUSION: OLV is widely practiced in Japan, primarily using DLTs, while the use of right-sided DLTs is limited. Concerns over technical difficulties and complications may hinder the use of right-sided DLTs.

BACKGROUND: Clinically important gastrointestinal bleeding (CIGIB) is a serious complication in critically ill patients, contributing to prolonged ICU stays and increased mortality. Despite efforts to identify high-risk patients, no previous studies have employed machine learning models to predict CIGIB during ICU stay or identify key predictors in this context. METHODS: This single-center retrospective study included ICU patients aged 18 years or older admitted between 2017 and 2024. Patients with ICU stays of less than 24 hours or GIB within 24 hours of admission were excluded. Machine learning models, including XGBoost, Random Forest, and L1-regularized logistic regression, were trained using patient data from the first 24 hours of ICU admission. Model performance was assessed using AUROC, precision, recall, and F1 scores. Shapley Additive Explanations (SHAP) were employed to evaluate key predictors. RESULTS: A total of 7,357 ICU patients were included, of whom 171 (2.3%) experienced CIGIB. The XGBoost model demonstrated the highest predictive performance with an AUROC of 0.84. Key predictors included APACHE III scores, hematocrit levels, APTT, creatinine and respiratory rate, while invasive mechanical ventilation and stress ulcer prophylaxis within the first 24 hours of ICU admission did not rank among the top 20 predictors based on SHAP values. CONCLUSIONS: This study represents the first application of machine learning for predicting CIGIB in ICU patients, providing valuable insights into risk stratification. The model demonstrated high predictive accuracy and interpretability, highlighting its potential to guide early intervention and prophylaxis. Further multi-center studies and interventional trials are needed to validate these findings and refine clinical risk prediction strategies.

An endotracheal tube (ETT) cuff leakage has serious consequences. Anatomical abnormalities are rare but are possible causes. We report the case of a patient having a robot-assisted laparoscopic prostatectomy. Endotracheal intubation was performed successfully. However, a cuff leak occurred, and persisted despite standard management efforts. The ETT was carefully advanced until one-lung ventilation was established and then gradually withdrawn until bilateral lung ventilation was restored. Chest computed tomography revealed a tracheal diverticulum immediately below the vocal cords as the underlying cause. If standard troubleshooting fails to resolve a cuff leak, unusual causes should be considered.

BACKGROUND: Patients with end-stage renal disease on hemodialysis (HD) undergoing cardiac surgery face increased risks. Mixed venous saturation (SvO2) is an important parameter representing the systemic oxygen supply-demand balance. However, interpreting SvO2 in HD patients may be challenging due to arteriovenous fistulas. The literature on these issues is lacking. This study aimed to investigate the change in SvO2 in HD patients by comparing those in non-HD patients perioperatively. METHODOLOGY: From April 1, 2019, to March 31, 2020, 39 patients undergoing cardiac surgery with pulmonary artery catheters, 18 with and 21 without HD, were identified. The cardiac index (CI) and SvO2 were extracted from patient records, and the oxygen delivery index (DO2I) was calculated before surgery (T0), on intensive care unit (ICU) admission (T1), 24 hours (T2), and 48 hours (T3) after ICU admission. A linear mixed effects model was applied for repeated measures analyses. RESULTS: T0 CI was significantly higher in the HD group (2.5 ± 0.5 vs. 2.0 ± 0.5 L/minute/m2, mean ± SD, P = 0.003) and increased significantly over time in both groups, without an interaction effect (P for interaction = 0.12). T0 SvO2 did not differ between groups (72 ± 10% vs. 72 ± 5%, P = 0.97) and decreased over time, more evidently in the non-HD group (P for interaction = 0.016). DO2I was similar in both groups perioperatively. CONCLUSIONS: SvO2 tended to be higher in the HD group perioperatively. If SvO2 in HD patients is similar to that in non-HD patients, this may mean that the oxygen supply-demand balance is disturbed.