Effect of N-acetyl-cysteine (NAC) added to fenoldopam or dopamine on end-tidal carbon dioxide and mean arterial pressure at time of renal artery declamping during cadaveric kidney transplantation

N-acetyl-cysteine (NAC) is known to be a powerful antioxidant used to prevent renal damage. Our deceased-donor kidney transplantation protocol administered an NAC bolus at the time of declamping of the renal artery to reduce the potential oxidative damage with ischemia-reperfusion. The aim of injury this study was to compare the effects of NAC added to a continuous infusion of either fenoldopam or dopamine during kidney recipient anesthesia on mean arterial pressure (MAP) and end-tidal carbon dioxide (ECO(2)), which were assumed to be expressions of oxidative and acid-base status. One hundred forty patients undergoing deceased donor kidney transplantation were enrolled in the study. Using a standardized perioperative anesthesia protocol, the patients were divided into 4 groups: group N, receiving an NAC (50 mg/kg) bolus just before renal artery declamping (n = 40); group C, not receiving any NAC or other infusion (n = 20); group NF, same treatment as group N plus fenoldopam (0.1 microg/kg/min) continuous infusion (n = 40); and group ND, same treatment as group N plus dopamine (3 microg/kg/min) continuous infusion (n = 40). We recorded the duration of kidney cold and warm ischemia and EtCO(2) and MAP values before and after arterial declamping, as well as subjective evaluations of graft perfusion and the incidence of early or delayed graft function and adverse events. EtCO(2) was higher and MAP lower in group C compared with group N; comparing groups N, ND, and NF, the NF regimen resulted in lower EtCO(2) and higher MAP values and a greater incidence of early graft function. Subjective evaluation of graft perfusion was more favorable for groups N, ND, and NC, particularly for NF. No significant periprocedural adverse events were recorded in the groups. In our experience, the association of an NAC bolus at the time of renal artery declamping and continuous infusion of fenoldopam resulted in a minor, though non-significant, increase in EtCO(2) values, higher MAP, and greater incidence of early graft function during deceased-donor kidney transplantation compared with no NAC or NAC plus renal-dose dopamine. Further studies are necessary to better define the potential role of oxidative damage in renal ischemia- reperfusion injury, including implications for outcome, as well as the potential role of the combination of NAC plus fenoldopam as a nephroprotective and outcome-modulating regimen.