Neonatal effect of remifentanil in cesarean section with general anesthesia: A protocol of systematic review and meta-analysis.

BACKGROUND: Although several previous studies have reported the efficacy of remifentanil in cesarean section (CS) under general anesthesia, no study has specifically addressed its neonatal effect (NE) in CS under general anesthesia systematically. Thus, this study will systematically investigate the NE of remifentanil in CS under general anesthesia. METHODS: Electronic databases including MEDLINE, EMBASE, Cochrane Library, Web of Science, Chinese Biomedical Literature Database, and China National Knowledge Infrastructure will be systematically retrieved with the assistance of a specialist librarian to check randomized controlled trials reporting NE in CS under general anesthesia. We will retrieve all electronic databases from their initial time to March 20, 2020 without restrictions of language. All process of study selection, data extraction, and risk of bias evaluation will be carried out by 2 independent authors. We will invite another senior expert to solve the problems that arise between 2 authors. Data will be pooled and analyzed using RevMan V.5.3 software. RESULTS: Outcomes consist of assessment of neonatal adaptation, requirements for postoperative respiratory support of neonates, systolic and diastolic noninvasive blood pressure, mean blood pressure, heart rate, electrocardiography, umbilical cord blood gas analysis, and adverse events. CONCLUSION: This study will present evidence of the NE of remifentanil in CS under general anesthesia. This information may inform benefits of intervention to guide the usage of remifentanil in CS under general anesthesia. STUDY REGISTRATION: INPLASY202040028.

Magnetic resonance imaging-navigated argon-helium cryoablation therapy against a rabbit VX2 brain tumor.

The aim of the present study was to investigate the feasibility of interventional magnetic resonance imaging (MRI)-guided and monitored argon-helium cryoablation for the treatment of brain tumors in rabbits. In addition, the present study evaluated the associations between imaging and pathology, the therapeutic effects and the effects on the surrounding normal tissues. A total of 14 rabbits were equally divided into groups C and D. Under general anesthesia, the skull was drilled and tumor blocks were implanted. Subsequently, a New Zealand rabbit VX2 brain tumor model was successfully established. Rabbits in group C were treated with argon-helium cryoablation and those in group D did not undergo any treatment (control). Regular postoperative MRI scanning was performed to observe the changes in tumor size, and the survival times of the rabbits in groups C and D were recorded. The extent of necrosis in the brain tumor exhibited a significant correlation with the freezing time of cryoablation, and the necrotic region was shown to be the same size as the ice ball. The survival times of the rabbits in the treatment group (group C) were significantly prolonged. Therefore, the observations of the present study demonstrated that the VX2 brain tumor model, produced using an improved tumor block implantation method, was stable and suitable for MRI observation and interventional study. In addition, argon-helium cryoablation was shown to be a safe and feasible therapeutic method for the treatment of brain tumors, and was demonstrated to significantly increase the survival times of the brain tumor-bearing rabbits.