[Hormones of the pituitary-adrenal cortex system in patients under long-term sedation with etomidate and fentanyl].

The influence of a long-term sedation with etomidate and fentanyl on the hormones of the pituitary gland and the adrenal cortex now five mechanically ventilated patients were studied. There is evidence that etomidate might diminish the plasma cortisol level in a dose dependent relationship. The urinary excretion of 17-OH-corticosteroids was found to stay within the normal range, whereas the corresponding excretion of the unbound cortisol stayed subnormal. In general no cortisol response was seen in connection with raised ACTH-plasma-levels. Surgical trauma and changes of dressing induced stress reactions with an exceeding rise in plasma cortisol levels. The plasma levels of prolactin showed a marked increase after the administration of fentanyl even in the presence of a high etomidate plasma level. 17-alpha-OH-progesterone and progesterone were found diminished at etomidate plasma levels greater than 1.0 micrograms/ml. In the "therapeutic range" there is found no linear dependency on the plasma etomidate level. From our preliminary results we cannot draw any conclusions about the mechanism how etomidate might inhibit cortisol synthesis and its influence on the metabolic rate, the hormonal feedback mechanisms and the cardiovascular system.