The protective effects of N-acetylsysteine in ischemia and reperfusion injury within open heart surgery

THE PROTECT VE EFFECTS OF N-ACETYLSYSTE NE N SCHEM A ANDREPERFUS ON NJURY W TH N OPEN HEART SURGERYPınar Köksal, MDSUMMARYThis study was designed to evaluate the efficacy of pre-operatively used intravenous N-acetylcysteine (NAC) ( 2 x 300 mg ) against ischemia-reperfusion (IR) injury in patientsundergoing cardiac surgery.20 patients were enrolled in this study. 10 patients were recieving NAC due tobronchopulmonary disease or bronchial secrection disorder at least 3 days prior to surgery.Samples were taken from central venous catheter for Malondialdehyde ( MDA ), Glutathione,Nitric oxide ( NO ), pro-Brain natriuretic peptide ( pro-BNP ), Creatine kinase-MB (CK-MB)and cardiac troponin levels ( cTnI ) before operation ( basal level: T0 ), 20 minutes after aorticcross clamping ( ischemia : T1 ), just after aortic decrossclamping ( reperfusion : T2 ), 6 hourslater following release of crossclamp ( 6th hour of reperfusion : T3 ) and 24 hours aftercrossclamp ( 24th hour of reperfusion : T4 ). Samples were taken from right atrium in order tomeasure tissue NO.Significant difference was not observed except aort crossclamping time withinintergroup comparisons ( p ≥ 0.05 ). Although not statistically significant, plasma CK-MB,cTnI, pro-BNP levels with tissue NO were found lower in study group. Furthermore, plasmaglutathion levels were elevated.Finally, this study didn?t reveal the protective effects of intravenous NAC (2x300mg ) against myocardial IR injury. Nevertheless, we concluded that the dose of NAC mighthave been administered in higher doses to cardiopulmonary by-pass prime followed by infusionin order to achieve the protective role against myocardial IR injury.