The effects of sevoflurane and isoflurane anesthesia on renal tubular function in patients with moderately impaired renal function

Increasing evidence indicates that sevoflurane anesthesia does not impair renal function in healthy patients despite higher concentrations of plasma inorganic fluoride. However, whether sevoflurane further affects renal tubular function in patients with impaired renal function is not known. We compared the effect of sevoflurane anesthesia with that of isoflurane anesthesia on renal tubular function in patients with moderately impaired renal function. Fourteen patients with creatinine clearance between 10 and 55 mL/min were anesthetized with either sevoflurane or isoflurane using a semiclosed circuit system. Plasma inorganic fluoride concentrations and urine N-acetyl-beta-D-glucosaminidase (NAG), gamma-glutamyltranspeptidase (gamma-GTP), and beta(2)-microglobulin (beta(2)MG) excretions were measured up to post-anesthetic day 14. Although both the peak plasma inorganic fluoride concentrations and the areas under the curve of plasma inorganic fluoride concentration versus time were significantly greater in the sevoflurane group than in the isoflurane group, urine NAG, gamma-GTP, and beta(2)MG excretions per day did not differ between the two groups. These results indicate that sevoflurane and isoflurane may have similar effects on the renal tubules in patients with moderately impaired renal function.