Objective To investigate the effects of sevoflurane postconditioning on lung function in patients undergo-ing heart valve prosthesis implantation with cardiopulmonary bypass (CPB). Methods Thirty patients, scheduled for heart valve prosthesis implantation, were randomly divided into control group (C, n=15) and sevoflurane postconditioning group (S, n=15). Anesthesia was maintained by intermittent intravenous injection of midazolam, fentanyl and pipecuronium. In group S, 2%sevoflurane was inhaled continuously for 15 min , 2 min before aortic unclamping. Blood samples were taken at 30 min before CPB (T2), 30 min after CPB (T3), 6 h (T4), 12 h (T5) and 24 h (T6) after operation. The values of p(O2), SaO2, airway peak pressure (Ppeak) and airway plateau (Pplat) pressure during the time of mechanical ventilation were recorded. Oxygen index (OI), alveolar arterial oxygen tension difference (AaDO2), dynamic pulmonary compliance (Cdyn) and static pulmonary compli-ance (Cstat) were calculated. Results Compared with group C, the values of SaO2 and Cdyn were significantly higher in group S after 30 min of CPB. The values of OI, p(O2), Cdyn and Cstat were significantly higher in group S than those of group C after 6 h of operation. The value of AaDO2 was significantly lower 12 h and 24 h after operation than that of group C (P＜0.05). Conclusion CPB led to the lung injury. The sevoflurane postconditioning has a protective effect on lung function in pa-tients undergoing cardiac valve replacement with CPB.

Objective To investigate the relationship between the changes in intracranial excitatory amino acid(EAA) levels and the incidence of postoperative cognitive dysfunction (POCD) in eldedy patients after general anesthesia. Methods Forty ASA Ⅰ-Ⅲ patients of both sexes aged 65-79 yr weighing 48-76 kg undergoing elective non-cardiac surgery under general anesthesia were studied.Anesthesia was induced with midazolam,fentanyl,etomidate and succinylcholine and maintained with continuous iv infusion of propofol,remifentanil,isoflurane inhalation and intermittent iv boluses of vecuronium.The right internal jugular vein was cannulated with a catheter which was advanced cephalad until jugular bulb.The jugular bulb venous blood samples were taken before (T0,baseline),at the end of (T1) and at 24,48 and 72h(T2-4) after operation for measurement of plasma concentrations of glutamate (Glu),aspartate (Asp) and glycine (Gly) by RP-HPLC.The cognitive function was evaluated by mini-mental state examination (MMSE) at T0 and T4.Results Eleven of the 40 patients developed POCD (28%).The plasma Gh,Asp and Gly concentrations were significantly increased after operation as compared with the baseline values in POCD patients and were significantly higher than in non-POCD patients.The plasma concentrations of Glu and Asp were negatively correlated with MMSE score(Glu:r=-0.86.P<0.01;Asp:r=-0.99,P<0.01).Conclusion Elderly patients may develop POCD after operation performed under general anesthesia through increase in intracranial EAA levels.