ABSTRACT
Objective To investigate the effects of ketamine combined with moderate hypothermia on brain ischemia-reperfusion (I/R) injury in a rat model of asphyxial cardiac arrest. Methods Fifty healthy Wistar rats of both sexes aged 4.0-4.5 months, weighing 410-510 g were randomly allocated into 5 groups (n = 10each): group Ⅰ sham operation (group S), group Ⅱ asphyxial cardiac arrest (group ACA), group Ⅲ ketamine (group K), group Ⅳ moderate hypothermia (group MH) and group Ⅴ K + MH. The animals were anesthetized with intraperitoneal (IP) phenobarbital 20 mg/100 g, tracheostomized and mechanically ventilated (RR 60 bpm,FiO2 50%), PaCO2 was maintained at 35-45 mm Hg. Cardiac arrest was induced by clamping tracheal tube until ECG activity disappeared and MAP ＜ 15 mm Hg. Resuscitated was started 5 min later. MAP ＞ 60 mm Hg and HR ＞ 250 bpm were considered to be signs of successful resuscitation. Dead animals and animals in which resuscitation time was longer than 5 min were excluded from the study. In group K ketamine 100 mg/kg was administered IP at 5 min before asphyxia. In group MH hypothermia was started as soon as asphyxia was started and body temperature was maintained at 30-35 ℃. After successful resuscitation, the animals were sacrificed. Their brains were removed for determination of brain water content and p-caspase-3 expression in hippocampus. Results Brain I/Rsignificantly increased brain water content and p-caspase-3 expression in group ACA. MH alone significantly attenuated 1/R-induced brain edema and decreased p-caspase-3 expression, while ketamine alone only significantly decreased p-caspase-3 expression but did not decrease I/R-induced brain edema. MH + K decreased p-caspase-3expression further but did not reduce brain edema further as compared with MH alone. Conclusion Ketamine combined with moderate hypothermia provides better protection against brain I/R injury.
ABSTRACT
Objective To assess the efficacy of laryngeal mask airway Proseal (LMA Proseal) and Supreme (LMA Supreme) used in patients undergoing laparoscopic surgery when the cuff-pressure was 35 cm H2O.Methods Sixty ASA Ⅰ or Ⅱ patients, aged 20-70 yr, weighing 50-80 kg, undergoing elective laparoscopic surgery, were randomized into2 groups (n = 30 each): LMA ProSeal group (group P) and LMA Supreme group (group S). After the LMA Proseal and LMA Supreme were inserted in group P and S respectively, the cuff pressure was monitored and maintained at 35 cm H2O by manipulate manometer. The airway sealing pressure, peak and mean airway pressure before and after pneumoperitoneum during mechanical ventilation and the complications were also recorded. Results The peak airway pressure was significantly higher after pneumoperitoneum than before pneumoperitoneum during mechanical ventilation (P ＜ 0.05), but there was no significant difference in the peak airway pressure before and after pneumoperitoneum between the two groups ( P ＞ 0.05). The air leakage had never happened before or after pneumoperitoneum during mechanical ventilation. There was no significant difference in the airway sealing pressure between the two groups ( P ＞ 0.05). There was no significant difference in the incidence of throat pain between the two groups(P＞0.05).Conclusion When the cuff pressure is 35 cm H2O, the LMA ProSeal and Supreme can provide adequate ventilation during operation with fewer complications and can be used safely for laparoscopic surgery.