Study of the renal function during anesthesia with halothane and enflurane.

In this work, the renal function of ten patients has been studied during an anesthesia with halothane (5 patients) or enflurane (5 patients), a new volatile anesthetic agent. Before and during the anesthesia, the patients were perfused with Lactate Ringer solution. Blood and urine samples were regularly collected to allow the measures of the various parameters of the renal function. Halothane decreases the glomerular filtration rate, the renal plasmatic flow; the filtrated fraction remains stable. Enflurane decreases the glomerular filtration rate but increases the renal plasmatic flow; besides the filtrated fraction decreases. As far as water and electrolytes are concerned, halothane mainly decreases the urine output, the osmolar clearance and the fractional excretion of sodium. This suggests that it chiefly acts on the proximal tube of the nephron. Enflurane mainly decreases the urine output and the free water clearance. This suggests an effect on the distal tube of the nephron.