Use Of Propofol Anesthesia With Bispectral Index Monitor Prompt Early Extubation In Adult Liver Transplanted Patients

Part I The feasibility of early extubation in adult liver transplanted patients under propofol anesthesia with bispectral index monitoringObjective:To assess the feasibility of early extubation in the operating room after adult liver transplantation (LT) by using target controlled infusion (TCI) of propofol with bispectral index (BIS) monitoring.Methods:105LTs in103adult recipients were included in the study. BIS monitor was used to reflect the depth of anesthesia in all patients. Effect-site target controlled infusion of propofol was used for anesthesia induction. Propofol target concentration was adjusted by BIS readings to maintain BIS at the range of40-60during the dissection phase. Propofol infusion was suspended just before portal vein clamping, and was resumed at BIS>60during the anhepatic or neohepatic phases. Effect-site TCI of remifentanil3.2ng/ml was initiated and kept mainly at constant throughout the operation. A multivariate, logistic regression analysis was performed to identify predictors for prolonged postoperative ventilation, as well as amnesia for extubation procedure. Intraoperative propofol requirements among groups divided by Chlid classification of liver function were compared.Results:92cases (87.6%) were immediately extubated in the operating room with a mean time of24min postoperatively.5cases (5.4%) were re-intubated due to re-operation within24hr postoperatively. Logistic regression analysis did not identify risk factors for prolonged ventilation postoperatively. Propofol target concentrations during induction and intubation were significantly lower in patients with Child C than the others, and the number of patients that did not required propofol infusion during the anhepatic or/and neohepatic phases were different significantly among the three groups (P<0.05).21of92cases (22.8%)that were immediate extubated in the operating room had no recall for extubation experience and were related with the lower BIS values at extubation (P<0.0001; odds ratio=0.826)Conclusion:Early extubation in the operating room after adult liver transplantation during propofol total intravenious anesthesia with bispectral index monitoring was feasible. Part Ⅱ Intra-patient reproducibility of bispectral index in adult liver transplanted patients under propofol anesthesiaObjective:To assess the reproducibility of bispectral index (BIS) by analyzing the agreement between bilateral BIS values placed concurrently on the same patient that underwent liver transplantation (LT) during propofol anesthesia.Methods:34patients that were early extubated after LT with propofol total intravenous anesthesia had BIS sensors applied to either side of their forehead. Left lateral BIS values were used solely for adjustment of propofol target concentration. The paired BIS data were analyzed by using correlation analysis and Bland-Altman methods. If the95%limits of agreement of bias between bilateral BIS values ranged within±10BIS, it was defined as clinical interchangeable. In addition, how many and what percentage of the different depth of anesthesia reflected by bilateral BIS readings, as well as the BIS readings differed by10BIS unit were established. We repeated this analysis with the data that only included time periods of3min (three sequential paired data points) or longer.Results:A total of15089paired data were collected. The bias of BIS(left-right) was-1.5, and the95%limits of agreement between them were-11to8. Correlation (R) was0.9(P<0.0001). As for the individuals, the95%limits of agreement in7cases (20.6%) did not fall within the predetermined limits of agreement of±10BIS unit. The bias of BIS(ieft-right) was-1.4, and the95%limits of agreement between them were-10to7after precluding the data that collected from pre-incision and after the end of surgery. There were still3cases (8.8%) that its95%limits of agreement did not fall within the predetermined range. Overall,14.5%of concurrent BIS readings suggested conflicting depths of anesthesia.1.2%of the time, there were sustained periods of3min or greater where the simultaneous bilateral BIS values suggested conflicting depths of anesthesia.5.2%of the time, there were difference that the simultaneous BIS differed by10or greater, and0.4%of the time, there were sustained periods of3min or greater in those differences.Conclusion:In LT patients under propofol anesthesia, the BIS readings between the left and right sides were clinical interchangeable. BIS readings from each side of electrode can be used for assessing the depth of anesthesia PartⅢ Early extubation in adult liver transplanted patients with bispectral index monitoring:A comparison of propofol/remifentanil anesthesia and sevoflurane/remifentanil anesthesiaObjective:To evaluate the influence of propfol/remifentanil anesthesia and sevoflurane/remifentanil anesthesia, by using bispectral index(BIS) monitoring, on emergency and extubation time in liver transplanted patients and then the accessibility of these two anesthesia methods. Methods:52adult patients underwent liver transplantation were randomly, equally divided into2group:group propofol (Pro group) and group sevoflurane (Sev group). BIS monitor was used in all patients and the readings were maintained at no more than60during the operation. Propofol target concentration or sevoflurane concentration was adjusted according to the BIS values during the operation. The time of emergency and extubation, the frequency of anesthesia adjustment and the patient’s recall for operation intraoperatively were compared.Results:49patients were immediately extubated at the end of surgery. The time from discontinued propofol infusion to emergency was significantly longer than that in Sev group (P<0.05), although the time form the end of surgery to either emergency or extubation were similar (P>0.05). In order to maintain the similar depth of anesthesia indicated by BIS, propofol infusion was adjusted more frequently than sevoflurane administration (P<0.05).Conclusion:When BIS monitoring was used for early extubation in liver transplanted patients, either propofol/remifentanil anesthesia or sevoflurane/remifentanil anesthesia had no influence on the time of emergency and extubation. Application of pfopofol/remifentanil anesthesia in this population seems needs more expirence than sevoflurane/remifentanil anesthesia, while the latter is relatively easy to grasp by beginner.