Total intravenous anesthesia: effects of opioid versus hypnotic supplementation on autonomic responses and recovery

Abstract

During radical prostatectomy procedures under total intravenous anesthesia, acute hemodynamic responses to retropubic dissection (30% +/- 8% to 36% +/- 12% [mean +/- SD] increases in mean arterial pressure) were treated with supplemental doses of either an opioid analgesic (alfentanil) or a sedative-hypnotic (propofol) to return the mean arterial pressure to within 10% of the preincision value. Although both drugs were effective, control with propofol required 10.1 +/- 2.5 min compared with 6.3 +/- 2.6 min in the alfentanil group (mean +/- SD; P < 0.01). Plasma stress hormone concentrations increased significantly in response to this surgical stimulus: epinephrine increased from 246% +/- 169% to 283% +/- 330%; norepinephrine increased from 44% +/- 33% to 83% +/- 104%; and antidiuretic hormone increased from 1300% +/- 1591% to 1700% +/- 1328%. Both alfentanil and propofol were equally effective in returning the catecholamine concentrations to their preincision levels. However, antidiuretic hormone levels remained above preincision values in both groups. Despite earlier awakening (3.4 +/- 2.9 vs 9.1 +/- 6.8 min; P < 0.05) in the alfentanil treatment group, there was no difference in time to spontaneous ventilation or tracheal extubation between the groups. In addition, 36% of the alfentanil-treated patients required antihypertensive therapy in the postanesthesia care unit compared with only 9% in the propofol group (P < 0.05). Postanesthesia care unit and hospital discharge times were similar in both treatment groups. We conclude that supplemental doses of alfentanil or propofol were equally effective in controlling acute hemodynamic and hormonal responses to surgical stimuli during total intravenous anesthesia.