RESUMEN
Objective To evaluate the effects of dexmedetomidine on the expression of tumor necrosis factor-α(TNF-α) and intercellular adhesion molecule-1 (ICAM-1 ) during cerebral ischemia-reperfusion (I/R ) in rats .Methods Thirty-six male Sprague-Dawley rats , aged 8-12 weeks ,weighing 280-320 g ,were randomly divided into 3 groups ( n= 12 each ):sham operation group (group S ) , cerebral I/R group (group I/R ) and dexmedetomidine group (group D ) .The animals were anesthetized with 10% chloral hydrate 3.5 ml/kg .The focal cerebral ischemia was induced by middle cerebral artery occlusion using a nylon thread with rounded tip inserted into internal carotid artery and advanced cranially until resistance was met .In group D ,dexmedetomidine 3μg/kg was injected intravenously immediately after beginning of ischemia ,followed by infusion at 3μg·kg-1 ·h-1 for 120 min ,while the equal volume of normal saline was given in group I/R .Four rats from each group were chosen at 24 ,48 and 72 h of reperfusion , and blood samples were taken from the left ventricle to determine the concentrations of serum S100B protein .The rats were then sacrificed and the brains were removed to determine the expression of TNF-αand ICAM-1 in brain tissues .Results Compared with group S ,the concentrations of serum S100B protein were significantly increased , and the expression of TNF-α and ICAM-1 in brain tissues was up-regulated in I/R and D groups ( P<0.05) .Compared with group I/R ,the concentrations of serum S100B protein were significantly decreased , and the expression of TNF-α and ICAM-1 in brain tissues was down-regulated in group D ( P<0.05 ) .Conclusion The mechanism by which dexmedetomidine reduces the cerebral I/R injury is related to down-regulation of TNF-αand ICAM-1 expression in rats .
RESUMEN
Objective To investigate the effect of parecoxib on intrapulmonary shunt during one-lung yentilation in patients undergoing esophageal cancer operation. Methods Forty-five ASA Ⅰ orⅡ patients of both sexes aged 47-57 yr weighing 42-59 kg undergoing esophageal cancer resection were randomly divided into 2 groups:control group (group C,n = 23) and parecoxib group (group P,n = 22). Left radial artery and right internal jugular vein were cannulated for MAP and CVP monitoring and blood sampling. Parecoxib 40 mg in 10 ml of normal saline was injected iv slowly before induction of anesthesia in group P while in group C normal saline 10 ml was injected instead of parecoxib. Anesthesia was induced with TCI of propofol (Ce 4 μg/ml) and sufentanil (Ce 0.3 ng/ml). Insertion of double lumen tube was facilitated with rocuronium 0.9 mg/kg. Correct position of the double lumen tube was verified by fiberoptic bronchoscopy. Anesthesia was maintained with TCI of propofol and sufentanil and intermittent iv boluses of cis-atracurium. BIS was maintained at 50-55 during operation. MAP, HR, CVP,mean airway pressure were monitored and recorded after induction of anesthesia (To), at 15, 30 min and 1 h of OLV (T1.2.3) and 30 min and 1 h after re-expansion of the collapsed lung (T4.5). Blood samples were taken simultaneously from jugular vein and radial artery for blood gas analysis. Intrapulmonary shunt (Qs/Qt) was calculated.Results There was no significant difference in MAP, HR, CVP, mean airway pressure and Qs/Qt during onelung ventilation between the two groups. Conclusion Parecoxib has no effect on hypoxic pulmonary vasoconstriction during one-lung ventilation in patients undergoing esophageal cancer resection.