Effect of neuroleptanaesthesia on adrenocortical function in man.

Many papers have been published concerning the effects of neuroleptanalgesia and anaesthesia on cardiovascular, respiratory and metabolic functions. However, no report has been published regarding its effect on adrenocortical function. Since neuroleptanaesthesia (NLA) diminishes cardiovascular sensitivity to adrenaline and noradrenaline (Janssen et al., 1963), it seems to be important from the homeostatic point of view, to know whether or not NLA blocks the normal adrenocortical response to surgical or anaesthetic stress. Previously, Oyama and his associates (1969) demonstrated that pethidine administered intramuscularly (2 mg/kg) 1 hour prior to induction of anaesthesia did not inhibit adrenocortical stimulation due to pre-operative emotional stress. Furthermore, pethidine-nitrous oxide anaesthesia alone for 30 minutes did not evoke adrenocortical activity, but could not block adrenocortical stimulation during surgical intervention and after operation. The present study was undertaken to investigate the effect of NLA on adrenocortical function, as judged by its influence on the free cortisol level in the plasma in twenty-two patients, and to compare the results with the effects of anaesthesia plus surgery.