The Effects Of Pneumoperitoneum And Head Down Position On Cerebral Oxygen Supply-consumption Balance And Energy Metabolism Anesthetized With Propofol Or Isoflurane

Objective The carbon dioxide which may expand the brain vessel could be absorbed from peritoneum when pneumoperitoneum was created. At the same time, the pneumoperitoneum would make abdomen pressure hoist, which would bring the center vessel pressure high. So the cerebral blood circumfluence resistance was enlarged. These above effects induced intracranial pressure high. The propofol and isoflurane have the protection effect of cerebral .How did cerebral oxygen delivery, oxygen consumption and energy metabolism change in gynecologic laparoscopic surgery anesthetized with propofol or isoflurane? This study observed it by jugular bulb blood gas, sugar and lactic.Methods 24 ASA grade I - II patients undergoing gynecologic laparoscopic surgery without known cerebral or cardiovascular system disease were selected. Anesthesia were induced and maintained with propofol (12 cases, group P) or isoflurane (12 cases, group I), fentanyl and vecuronium. Paired, repeated samples of the arterial and jugular bulb blood were analyzed for oxygen, glucose and lactic acid before anesthesiaf before pneumoperitoneum, 10, 20, and 60min after pneumoperitoneum, respectively.Results Jugular bulb oxygen saturation (SjO2) jugular bulb pressure (JBP) and plasma glucose level increased and cerebral ateriovenous oxygen content difference( D(a-jO2) decreased significantly after pneumoperitoneum, while the cerebral ateriovenous plasma glucose difference(D (a-j) glu) and plasma lactic acid level were constant. Between the two groups there were no significant differents of those above results except SjO2. The SjO2 of group I was higher than group P.Conclusions Increased SjO2 indicated that cerebral oxygen supply exceeded oxygen consumption. Increased JBP resulted in ICP hoist when pneumoperitoneum was set up. However, brain energy metabolism was not impacted during head-down pneumoperitoneum anesthetized with not only propofol but also isoflurane. Total intravenous anesthesia with propofol isprobably more suitable for this kind of operation because higher SjO2 in group I mean cerebral hyper-perfusion.