POTENTIIAL PROTECTIIVE EFFECT OF N--ACETYL CYSTEIINE ON RENAL FUNCTIION DURIING CARDIIOPULMONARY BYPASS IIN COMPARIISON TO MANIITOL

Abstract

species(ROS)(Ulus etal., 2003) which have been shown to impair renal function(Tepel et al., 2000). Thus, ROS might be involved in the etiology of CPB-related renal function impairment. Because use of the antioxidant and ROS-scavenger N-acetylcysteine (NAC) reduces ROS-induced renal dysfunction in patients subjectedto radiographic contrast agents, the neutrophil oxidative burst response to CPB(Tossios et al., 2003)., and direct ROS mediated myocardial alterations (Tossios et al., 2003). We hypothesized that NAC may also protect renal function in patients subjected to cardiac surgery on CPB. Mannitol is a traditionally osmotic diuretic with several suggested benefits in the perioperative period. Theoretically, it increases intravascular volume, improving preload and cardiac output, increases blood to the kidneys through the release of atrial natriuretic peptide, and facilitates the flushing of debris from renal tubules by increasing urinary output.Mannitol is known to have additional properties as a free radical scavenger, which may help attenuate the effects of reperfusion injury (Gude & Jha, 2007). Substantial evidence supports the prophylactic use of the antioxidant N-Acetyl Cysteine (NAC), along with intravascular volume expansion, for the prevention of radio-contrast nephropathy. In experimental studies, NAC has attenuated renal dysfunction through different anti-inflammatory and antioxidant effects such as antagonism of tumor necrosis factor and inhibition of the vascular cell adhesion molecule expression.Furthermore; NAC has been shown to prevent cardio- pulmonary bypass pump–induced inflammatory response(Sucu et al., 2004). Our data suggest effective renal protection by the use of N-acetyl cysteine as it prevented rise is serum creatinine and cystatin c when compared to the mannitol andcontrol group. This is in agreement with Fischer et al.,who used double-blind, placebo-controlled clinical trial on patients undergoing on CPB cardiac surgery who had received either NAC (group; n = 20) or placebo (n = 20) with respect to serum creatinine change from pre-operatively to postop day 1 and day 2 as well as diuretic medication and diuresis during the first 24 h post surgery, that study showed effective protection by N-acetyl cysteine as non-significantchanges in serum creatininefrom pre to postoperative in comparison to placebo group which showed significant changes(Fischer et al., 2005). The study by sucu et al., to investigate the effect of N-acetylcysteine on preventing pump-induced oxidoinflammatory response during cardiopulmonary bypass, which was done on a Forty patientsundergoing(CABG) were randomly divided into a study group (n20), acetylcysteine and control group (n20)samples were collected for measurement of myeloperoxidase (MPO), malondialdehyde (MDA), interleukin-6, α1-acid glycoprotein (AAGP), and C-reactive protein (CRP) during surgery and postoperatively as oxidoinflamatory markers. the study showed that NAC pretreatment reduced the CBP-induced oxidoinflammatory response, possibly by preventing the oxidoinflammatory cascade activation, as indicated by the marked attenuation of the markers(Sucu et al., 2004). In the study of Ramesh to detect the reno-protective effect of N acetyl cysteine (n 27) in Patients undergoing coronary angiography and Interventions in comparison to a control group (n 24) the study concluded that prophylactic oral administration of the antioxidant acetyl cysteine reduced the incidence of an acute reduction in renal function by contrast agents in patients who underwent coronary angiography with or without intervention (Ramesh et al., 2006). In a rat cardiopulmonary bypass model study by zhu et al., the N-acetyl cysteine was able to ameliorate acute renal injury in the treated group of animal in comparison to untreated group, represented in serum creatinine and cystatin C measurement, pre and post CPB(zhu et al., 2007).