Hydroxyethyl starch (HES) does not directly affect renal function in patients with no prior renal impairment

Study Objective: To examine the effects of hydroxyethyl starch (HES) on ren al function. Design: Randomized, controlled trial. Setting: Operating theatre of a university hospital. Patients: 60 ASA physi cal status I and II male patients undergoing middle ear surgery. Interventions: Patients received either lactated Ringer's solution (LRS) or one of three HES solutions. Tile HES solutions were administered in a dose of 15 mL/kg bodyweight (bw), the Ringer's solution in a dose of 60 mL/kg b w, after induction of anesthesia oz,er a period of one hour. Measurements: Blood and urine samples for hormone and enzyme tests were obt ained at defined timer before, during and after surgery. Urine excretion, g lomerular filtration rate (GFR), renal plasma flow and routine hemodynamic parameters were measured simultaneously. Main Results: There were no significant Intergroup differences regarding GF R, renal plasma flow or tubular and glomerular integrity as measured by spe cific proteins and enzymes (alpha -1-microglobulin, Tamm-Horsfall-protein, immunoglobulin G, and N-acetyl-beta -D-glucosaminidase). Arginine vasopress in decreased in all groups during and following anesthesia, aldosterone and plasma renin activity decreased only in the HES groups, and angiotensin II decreased only In the HES 200/0.5 group. Central venous pressure increased during fluid administration in the LRS group and returned to baseline soon er in the HES groups. Conclusions: Hydroxyethyl starch administration appears to be risk-free wit h regard to renal function in patients without p preexisting renal dysfunct ion who undergo general anaesthesia. The relevance of the decrease in aldos terone, following HES therapy needs further investigation. (C) 2001 by Else vier Science Inc.