Adrenal Function During Long-Term Anesthesia in Man 1

Summary

Plasma 11-OHCS were measured in 12 subjects during 7 hr of general anesthesia with endotracheal nitrous oxide (N₂O) and halothane, and halothane alone. The 5 subjects who received the N₂O-halothane anesthesia showed an early rise in plasma 11-OHCS, which corresponded to the duration of the excitation phase. After the short rise, the plasma 11-OHCS fell to hypoadrenal levels. The subjects who received halothane only (rapid induction of anesthesia) showed no rise in plasma 11-OHCS, but the 11-OHCS fell to hypoadrenal levels after induction. After 2 to 4.5 hr of general anesthesia, the plasma 11-OHCS rose spontaneously and remained elevated until the end of anesthesia. The sudden rise was not due to changes in feedback threshold and did not correlate with changes in concentration of the anesthetic. The urinary catecholamine secretion was not significantly altered during the anesthesia compared to a control period.