Renin-aldosterone system alterations during abdominal gynaecological operations under general or combined general and...

Alterations of plasma renin-activity and aldosterone levels were comparatively studied in 41 premenopausal patients who were subjected to total abdominal hysterectomy. Twenty-one women received general anaesthesia (group A) and 20 received a combination of general and epidural anaesthesia (group B). Five blood specimens were drawn from each patient in order to determine plasma aldosterone levels (PA) and plasma renin activity (PRA) by radioimmunoassay (RIA). The rise of PA levels in group A occurred 30 min after the initiation of surgery and at that time there was a statistically significant difference as compared with the epidural anaesthesia (EA) group (p < 0.001). PRA levels in both groups showed a rise of limited statistical significance at 30 minutes after the initiation of surgery (p < 0.05). During the remaining time intervals, group A did not show any significant changes, whereas group B showed a reduction of limited statistical significance (p < 0.05). General anaesthesia for gynecological abdominal surgery without the use of volatile agents significantly increases plasma aldosterone levels. Combined anaesthesia does not totally inhibit intraoperative hyperaldosteroism but it is much slower and is of great advantage for the patient.