Effect of sevoflurane on myocardial injury induced by hemorrhagic shock and resuscitation in pigs

Objective To evaluate the effect of sevoflurane on myocardial injury induced by hemorrhagic shock and resuscitation(HS/R)in pigs. Methods Twenty-four Bama miniature pigs(12 males, 12 females), weighing 20-25 kg, aged 3-5 months, were randomly divided into 3 groups(n=8 each)using a random number table: sham operation group(group S), HS/R group and sevoflurane group(group Sev). The left and right femoral arteries and right femoral vein were cannulated for blood pressure monitoring, blood-letting, blood sampling and fluid infusion.HS/R was induced by blood-letting maintaining for 1 h, followed by resuscitation with autologous blood reinfusion and infusion of lactated Ringer's solution 2 times the volume of the blood withdrawn.The pigs in group Sev were exposed to 2% sevoflurane for 30 min before resuscitation.After cannulation, at 30 min after hemorrhagic shock, before resuscitation, and at 30 min, and 1.5, 2.5 and 3.5 h after resuscitation, blood samples were collected from the femoral artery for determination of creatine kinase-MB(CK-MB)activity and cardiac troponin I(cTnI)concentration in serum using an automatic biochemical analyzer.Myocardial specimens were obtained at 3.5 h after resuscitation for detection of tumor necrosis factor-alpha(TNF-α)and interleukin-6(IL-6)contents(by ELISA), and phosphor-signal transducer and activator of transcription 1(p-STAT1)expression(by Western blot), and for examination of the pathological changes(with light microscope). Results Compared with S group, the CK-MB activity and cTnI concentration in serum and contents of TNF-α and IL-6 were significantly increased, and the expression of p-STAT1 was up-regulated in HS/R and Sev groups(P<0.05). Compared with HS/R group, the CK-MB activity and cTnI concentration in serum and contents of TNF-α and IL-6 were significantly decreased, and the expression of p-STAT1 was down-regulated(P<0.05), and the pathological changes of myocardia were alleviated in Sev group. Conclusion Sevoflurane can alleviate HS/R-induced damage to myocardia of pigs, and inhibited STAT1 activity and attenuated inflammatory responses in the myocardium are involved in the mechanism. Key words: Anesthetics, inhalation; Shock, hemorrhagic; Cardiopulmonary resuscitation; Myocardial reperfusion injury