Changes in renal artery resistance after meal-induced splanchnic vasodilatation in cirrhotic patients

Purpose. A relationship between vasomotor tone changes in mesenteric and re nal vessels in cirrhotic patients has been suspected but remains controvers ial. The aim of this study was to assess by duplex Doppler sonography the c hanges in the circulatory resistance of the renal arteries and superior mes enteric artery (SMA) following meal-induced splanchnic vasodilatation. Methods. Twenty-seven cirrhotic patients and 15 healthy volunteers with no hepatic or renal dysfunction were prospectively included in the study. The resistance index (RI) of the SMA and of the right and left renal arteries w as measured by duplex Doppler sonography before and 30 minutes after ingest ion of a standard 400-kcal balanced liquid meal. Values in controls and pat ients and values before and after the meal were compared, and correlations between Rls, Child-Pugh class (liver function), and creatinine clearance we re assessed in cirrhotic patients. Results. The fasting renal artery RI was greater in cirrhotic patients than in controls (p < 0.0001), but there was no difference in fasting SMA Rls. After the meal, there was a significant decrease in the SMA RI in controls (0.85 +/- 0.04 before versus 0.74 +/- 0.03 after meal, p = 0.0001) and in c irrhotic patients (0.85 +/- 0.04 before versus 0.77 +/- 0.04 after, p = 0.0 001) and a significant increase in the renal artery RI (0.57 +/- 0.06 befor e versus 0.62 +/- 0.05 after in controls, p = 0.001; 0.68 +/- 0.07 before v ersus 0.70 +/- 0.07 after in cirrhotic patients, p = 0.001). No correlation was found in cirrhotic patients between the changes in renal artery RI and the postprandial SMA RI decrease, the Child-Pugh class, or the creatinine clearance. Conclusions. Meal-induced SMA vasodilatation (RI decrease) is associated wi th a marked increase in the renal artery RI, worsening the renal vasoconstr iction in cirrhotic patients. (C) 2001 John Wiley & Sons, Inc.