Changes in Renal Blood Flow and Real-time Renal Cortical Perfusion According to Low-dose Nitroglycerin and Dopamine Administration Following the Occlusion and Reperfusion of Liver Blood Flow in Experimental Dogs

Abstract

Background: Pringle maneuver and nitroglycerin (NTG) administration to educe hemorrhage during hepatectomy may affect renal blood flow (RBF) am renal cortical perfusion (RCP) by reducing blood pressure (BP), perload and others. However, so far there have been no studies on REF and RCP changes during and after hepatic vascular maneuver in hepatectomy. The purpose of this study was to evaluate the changes in RBF and RCP along with low dose (2/kg/min) NTG with or without low dose (3/kg/min) dopamine after the occlusion and reperfusion of hepatic blood flow. Methods: Eighteen mongrel dogs were divided into three groups according to drug administration after hepatic reperfusion; control group (group C, n = 6), NTG group (group N, n = 6), and NTG with dopamine group (group N-D, n = 6). After femoral arterial and central venous catheterization, a midline abdominal incision was made, and the hepatic artery (HA) and th portal vein (PV) were exposed for clamping and declamping. Thereafter, the right renal artery was exposed, and a doppler probe for measuring RBF was placed around the right renal artery, and a thermal diffusion microprobe was inserted in the renal outer cortex to measure RCP. Hemodynamics, RBF and RCP, were repeatedly measured before and after HA and PV reperfusion. Results: No significant change in heart rate was observed in any group. The BP decreased in all the groups after HA and PV occlusion. In group C, the BP recovered to the baseline level after hepatic reperfusion but not in groups N and N-D. The RBF and RCP decreased in all groups after HA and PV occlusion. The RBF increased compared to baseline in N-D after hepatic reperfusion, and the RCP increased versus baseline in N-D, 10 minutes after hepatic repefusion. Conclusions: In conclusion, it was observed that the RBF and RCP increased compared to baseline by administering dopamine during HA and PV reperfusion. Therefore, the prophylactic administration of low dose dopamine during hepatectomy offers an effective method of protecting renal function.