Anesthesia-induced modulation of in vivo antibody levels: a study of pentobarbital, chloral hydrate, methoxyflurane, halothane, and ketamine/xylazine.

The influence of anesthesia on long-term changes in in vivo antibody levels after antigen challenge was examined. Rats experienced a surgical plane of various anesthetics alone (anesthesia/intact) or in combination with laparatomy (anesthesia/laparatomy) and were given 1 or 3 wk to recover. Antigen, keyhole limpet hemocyanin, was then administered, and antibody levels specific to the antigen were measured during the next 14 days. Comparisons were made between anesthesia-treated animals and home cage controls. Pentobarbital and chloral hydrate produced decreases in in vivo antibody levels even 3 wk after exposure, whereas halothane, methoxyflurane, and ketamine/xylazine did not. Ketamine/xylazine produced moderate but not significant decreases in antibody levels when 1 wk intervened between exposure and antigen administration, but not when 3 wk intervened. Surgery did not produce larger changes in antibody levels than did anesthesia itself. These data suggest the possibility that some anesthetics, per se, may contribute to infection that may occur postoperatively.