The Effects Of Different Ways Of Conditioning With Sevoflurane Inhalation On Serum Concentration Of Troponin-t And IL-6, IL-8During And After Valve Replacement Surgery

Objective To investigate clinically the effects of sevoflurane preconditioning,sevoflurane postconditioning and combination of sevoflurane preconditioningand postconditioning on serum concentrations of troponin-T, IL-6, IL-8forexploring myocardial protection of these methods and the relationship withproinflammatory cytokines in adult patients during valve replacement surgeryunder cardiopulmonary bypass (CPB). Methods53patients scheduled for valvereplacement surgery under cardiopulmonary bypass (CPB) were enrolled anddivided randomly into4groups (n=13each): control group (group C)、sevoflurane preconditioning group (group S1)、sevoflurane postconditioninggroup (group S2) and combination of sevoflurane preconditioning/postconditioning group (group S3). Four groups was induced with intravenousinjection of midazolam, fentanyl, etomidate and rocuronium and ventilated afterendotracheal intubation. Midazolam, fentanyl and vecuronium were continuousinfused for maintenance of anesthesia. No sevoflurane was inhaled during theprocedure in group C.1%sevoflurane was inhaled after endotracheal intubationuntil aorta clamping in group S1.1%sevoflurane was inhaled after aortadeclamping and vena cava release in group S2.1%sevoflurane was inhaledafter endotracheal intubation until aorta clamping and after aorta declampingand vena cava release in group S3. ECG, HR, SBP, DBP, MAP, CVP, SpO2,PETCO2and PETsevo were monitored intraoperatively, and duration of CPB,aortic declamping time, automatic cardiac rebeating rate and arrhythmiarecorded. The artery blood samples were collected for the measurements of serum concentration of cTnT, IL-6and IL-8immediately after anesthesiainduction(T0), at2h after aorta declamping (T1), at6h after aorta declamping(T2), at12h after aorta declamping (T3), at24h after aorta declamping (T4)respectively. Results1.There were no remarkable difference in age, sex, weight,height, preoperative EF, ASA classification, NYHA classification, surgicalapproaches among four groups(p>0.05).2. There were no remarkabledifference in duration of CPB and aorta occlusion, type of CPB primingsolution, hours staying in ICU and being ventilated, endotracheal tube keepinghours, infusion hours of vasoactive drugs, hospital-stay days among fourgroups(p>0.05). Automatic cardiac re-beating rates in group S1、group S2andgroup S3was significantly higher than in group C (p<0.05).3. There was nodifference in the serum concentration of troponin-T among four groups at T0(p>0.05). Comparing with T0, the serum concentration of troponin-T increasedmarkedly in all groups at T1, T2, T3and T4(p<0.05). However, The serumconcentration of troponin-T was significantly lower in the group S1, S2and S3than in the group C at T1, T2and T3(p<0.05). At T4, the serum concentrationof troponin-T was significantly lower in the group S1and S3than in the groupC(p<0.05), but there was no difference in the serum concentration oftroponin-T between the group S2and group C (p>0.05). After aorta declampingno difference was found in the serum concentration of troponin-T among thegroup S1, S2and S3(p>0.05).4. There was no difference in the serumconcentration of interleukin-6among four groups at T0(p>0.05). Comparingwith T0, the serum concentration of interleukin-6increased markedly in allgroups at T1, T2, T3and T4(p<0.05). The serum concentration of interleukin-6was significantly lower in the group S1, S2and S3than in the group C at T1,T2, T3and T4(p<0.05). After aorta declamping there was no difference in theserum concentration of interleukin-6among the group S1, S2and S3(p>0.05).5. There was no difference in the serum concentration of interleukin-8among four groups at T0(p>0.05). Comparing with T0, the serum concentration ofinterleukin-8increased markedly in all groups at T1, T2, T3and T4(p<0.05),but at T4the serum concentration of interleukin-8decreased nearly to the basiclevel in the group S1, S2and S3(p>0.05). The serum concentration ofinterleukin-8was significantly lower in the group S1, S2and S3than in thegroup C at T1, T2, T3and T4(p<0.05). After aorta declamping there was nodifference in the serum concentration of interleukin-8among the group S1, S2and S3(p>0.05).6. Correlation analysis revealed a Linear positive correlationbetween the serum concentration of troponin-T and the serum concentration ofinterleukin-6in the group C(R=0.331, p<0.05) and a Linear positive correlationbetween the serum concentration of troponin-T and the serum concentration ofinterleukin-8in the group C(R=0.292, p<0.05). Conclusion1. The findings inthe study revealed that sevoflurane preconditioning, sevoflurane post-conditioning and combination of sevoflurane preconditioning/postconditioningcan all remarkably lessen the release of troponin-T, which implies thatmyocardial ischemia-reperfusion injury may be attenuated effectively by meansof sevoflurane conditioning described above.2. There is no difference inattenuating troponin-T expression among in three conditioning groups, whichsuggests that all the conditioning modes can protect myocardium from I/Rinjury to a similar extent.3. Linear positive correlations were found to existbetween expression of cTnT and IL-6or IL-8. All three methods cansimultaneously inhibit production and over expression of interleukin-6andinterleukin-8, which implies that the myocardial protection of them may berelated to attenuation of systemic inflammatory response syndrome.