Objective:To develop and validate a predictive model for massive hemorrhage during brain tumor resection in pediatric patients.Methods:A retrospective analysis was performed on the clinical data from pediatric patients who underwent elective brain tumor resection under general anesthesia at the Women and Children′s Medical Center Affiliated to Guangzhou Medical University from December 2016 to October 2023. The patients were randomly divided into model group and internal validation group in a ratio of 8∶2. Pediatric patients who underwent elective brain tumor resection under general anesthesia at Qilu Hospital of Shandong University from January 2021 to July 2024 were selected and served as external validation group. Relevant characteristic variables were screened through Lasso regression. A multivariate logistic regression was used to develop the model and plot the nomogram for intraoperative massive hemorrhage. The performance of the model was evaluated using the area under the receiver operating characteristic curve and calibration curve.Results:Through Lasso regression and multivariate logistic regression analyses, 11 independent influencing factors were identified: age ( OR=0.323, 95% confidence interval [ CI]: 0.280-0.374, P<0.001), weight ( OR=0.164, 95% CI: 0.135-0.199, P<0.001), activated partial thromboplastin time ( OR=1.133, 95% CI: 1.036-1.239, P=0.006), thrombin time ( OR=1.141, 95% CI: 1.048-1.243, P=0.002), red blood cell count ( OR=0.941, 95% CI: 0.888-0.996, P=0.035), hemoglobin concentration ( OR=0.873, 95% CI: 0.822-0.926, P<0.001), platelet count ( OR=1.062, 95% CI: 1.001-1.127, P=0.048), maximum tumor diameter ( OR=2.384, 95% CI: 2.241-2.536, P<0.001), tumor invasiveness ( OR=2.376, 95% CI: 2.071-2.726, P<0.001), hydrocephalus ( OR=2.409, 95% CI: 2.139-2.713, P<0.001), and centered midline structure ( OR=0.509, 95% CI: 0.465-0.557, P<0.001). Based on this, a nomogram prediction model was established. The receiver operating characteristic curve showed that the area under the curve of this model in predicting the risk of massive hemorrhage during brain tumor resection was 0.936 (95% CI: 0.90-0.959) in model group, 0.863 (95% CI: 0.744-0.948) in internal validation group, and 0.855 (95% CI: 0.726-0.955) in external validation group. The calibration curve indicated good model consistency, and the Hosmer-Lemeshow goodness-of-fit test result showed a P value of 0.979 ( P>0.05). Conclusions:Age, body weight, activated partial thromboplastin time, thrombin time, red blood cell count, hemoglobin concentration, platelet count, maximum tumor diameter, tumor invasiveness, hydrocephalus and midline structure are independent influencing factors for major bleeding during brain tumor resection in pediatric patients, and the prediction model established based on this histogram has high accuracy.

Objective:To develop and validate a predictive model for massive hemorrhage during brain tumor resection in pediatric patients.Methods:A retrospective analysis was performed on the clinical data from pediatric patients who underwent elective brain tumor resection under general anesthesia at the Women and Children′s Medical Center Affiliated to Guangzhou Medical University from December 2016 to October 2023. The patients were randomly divided into model group and internal validation group in a ratio of 8∶2. Pediatric patients who underwent elective brain tumor resection under general anesthesia at Qilu Hospital of Shandong University from January 2021 to July 2024 were selected and served as external validation group. Relevant characteristic variables were screened through Lasso regression. A multivariate logistic regression was used to develop the model and plot the nomogram for intraoperative massive hemorrhage. The performance of the model was evaluated using the area under the receiver operating characteristic curve and calibration curve.Results:Through Lasso regression and multivariate logistic regression analyses, 11 independent influencing factors were identified: age ( OR=0.323, 95% confidence interval [ CI]: 0.280-0.374, P<0.001), weight ( OR=0.164, 95% CI: 0.135-0.199, P<0.001), activated partial thromboplastin time ( OR=1.133, 95% CI: 1.036-1.239, P=0.006), thrombin time ( OR=1.141, 95% CI: 1.048-1.243, P=0.002), red blood cell count ( OR=0.941, 95% CI: 0.888-0.996, P=0.035), hemoglobin concentration ( OR=0.873, 95% CI: 0.822-0.926, P<0.001), platelet count ( OR=1.062, 95% CI: 1.001-1.127, P=0.048), maximum tumor diameter ( OR=2.384, 95% CI: 2.241-2.536, P<0.001), tumor invasiveness ( OR=2.376, 95% CI: 2.071-2.726, P<0.001), hydrocephalus ( OR=2.409, 95% CI: 2.139-2.713, P<0.001), and centered midline structure ( OR=0.509, 95% CI: 0.465-0.557, P<0.001). Based on this, a nomogram prediction model was established. The receiver operating characteristic curve showed that the area under the curve of this model in predicting the risk of massive hemorrhage during brain tumor resection was 0.936 (95% CI: 0.90-0.959) in model group, 0.863 (95% CI: 0.744-0.948) in internal validation group, and 0.855 (95% CI: 0.726-0.955) in external validation group. The calibration curve indicated good model consistency, and the Hosmer-Lemeshow goodness-of-fit test result showed a P value of 0.979 ( P>0.05). Conclusions:Age, body weight, activated partial thromboplastin time, thrombin time, red blood cell count, hemoglobin concentration, platelet count, maximum tumor diameter, tumor invasiveness, hydrocephalus and midline structure are independent influencing factors for major bleeding during brain tumor resection in pediatric patients, and the prediction model established based on this histogram has high accuracy.

Objective To evaluate the relationship between macrophage migration inhibitory factor ( MIF) expression and obese-induced abolition of sevoflurane preconditioning-induced cardioprotection in mice. Methods Forty-eight male C57BL∕6J mice, aged 4 weeks, were divided into 2 groups ( n=24 each) using a random number table method: normal diet group ( Lean group ) and high-fat diet group ( Obese group) . Lean group were fed a normal diet ( 10％ kcal) for 12 weeks, while Obese group were fed a high-fat diet ( 60％ kcal) for 12 weeks. The weight of mice was measured. Blood samples were collected from the tail vein for determination of blood glucose concentrations, and plasma concentrations of total cho-lesterol, triglyceride, insulin and leptin. After measurement of the parameters mentioned above, Lean group and Obese group were divided into 3 subgroups ( n=8 each) using a random number table method:sham operation groups (L-Sham group, O-Sham group), myocardial ischemia-reperfusion groups (L-IR group, O-IR group) and sevoflurane preconditioning groups (L-IR+Sev group, O-IR+Sev group). The mice were anesthetized and their hearts were immediately removed and retrogradely perfused in a Langendorff apparatus with an oxygenated K-H solution at 37 ℃. Hearts were continuously perfused with K-H solution for 115 min in L-Sham and O-Sham groups. Hearts were subjected to global ischemia for 25 min, followed by 60-min reperfusion after being retrogradely perfused with K-H solution in L-IR and O-IR groups. In L-IR+Sev and O-IR+Sev groups, hearts were subjected to 3 cycles of 5-min perfusion with sevoflurane-contai-ning K-H solution ( final concentration 0. 6 mmol∕L) and 5-min washout, and then hearts were subjected to global ischemia for 25 min, followed by 60-min reperfusion. Left ventricular developed pressure ( LVDP ) , left ventricular end-diastolic pressure ( LVEDP ) , and the maximum rate of increase or decrease in left ventricular pressure ( ±dp∕dtmax) were recorded at the end of reperfusion. Hearts were obtained at the end of reperfusion for determination of myocardial infarct size and expression of MIF ( by Western blot) . Results Compared with Lean group, the weight, blood glucose, levels of plasma total cholesterol, tri-glyceride, insulin and leptin were significantly increased in Obese group (P<0. 05). Compared with L-Sham group, the LVDP and +dp∕dtmax were significantly decreased, LVEDP and -dp∕dtmax were in-creased, myocardial infarct size was increased, and the expression of myocardial MIF was up-regulated in L-IR and L-IR+Sev groups, and the expression of myocardial MIF was up-regulated in O-Sham group ( P<0. 05) . Compared with L-IR group, LVDP and +dp∕dtmax were significantly increased, LVEDP and-dp∕dtmax were decreased, myocardial infarct size was decreased, and the expression of myocardial MIF was up-regulated in group L-IR+Sev, and the expression of myocardial MIF was significantly up-regulated in group O-IR (P<0. 05). Compared with O-Sham group, LVDP and +dp∕dtmax were significantly de-creased, LVEDP and-dp∕dtmax were increased, and myocardial infarct size was increased, and no signif-icant change was found in the expression of MIF in O-IR and O-IR+Sev groups ( P>0. 05) . Conclusion The mechanism by which obese abolishes sevoflurane preconditioning-induced cardioprotection may be relat-ed to inducing MIF over-expression in mice.