Comparison of remifentanil versus fentanyl general anesthesia for short outpatient urologic procedures

Study objectives. To compare the effect of remifentanil versus fentanyl isoflurane general anesthesia on Aldrete score, emergence, extubation and discharge times from the operating room (OR) and postanesthesia care unit (PACU) following short outpatient urologic procedures (panendoscopy and cystoscopy, bladder hydrodilatation, stent placement). Patients and methods. 40 patients 18 years of age or older scheduled for short elective outpatient urological procedures with an expected duration of less than 30 minutes.

Following Institutional Review Board (IRB) approval and written informed consent, 40 American Society of Anesthesiologi-sts (ASA) physical class 1-3 adult outpatients were enrolled and equally (n=20) randomized into remifentanil and fentanyl groups. Preoperatively, all subjects received intravenous (IV) midazolam 1-2 mg and were induced with propofol 2 mg/kg IV. Muscle relaxation was achieved with succinylcholine or rocuronium, followed by intubation. The remifentanil group received remifentanil 1 g/kg IV at induction with a maintenance dose of remifentanil 0.1 to 2 g/kg/min IV in the presence 

of 60% nitrous oxide (N2O)/40% oxygen (O2) and end-tidal isoflurane of 0.3 to 0.4% (for amnesia). The fentanyl group received fentanyl 2 g/kg IV at induction, maintenance dose of fentanyl 2 to 3 g/kg IV intermittent bolus, and 60% N2O/40%O2 with 2% end-tidal isoflurane. Muscle relaxation was reversed at the end of anesthesia as needed. Times for OR entry, emergence, extubation, total OR time (entry to exit) and PACU discharge time, as well as Aldrete scores at time of OR exit and PACU discharge were determined. Data was evaluated by ANOVA, t-test and Mann-Whitney tests. A p<0.05 value was considered statistically significant.

Results. There was no significant difference between groups in age, gender, weight, ASA class, PACU analgesic or antie-metic use, or times of emergence, extubation, OR exit and PACU discharge. There was a significant difference (p<0.05) in OR exit Aldrete score but not PACU discharge Aldrete score. No adverse events were noted.

Conclusions. While there was no difference between the remifentanil and fentanyl groups regarding recovery time from OR and PACU, remifentanil patients had significantly better OR exit Aldrete scores with less sedation upon arrival at phase I PACU recovery than the fentanyl group. This anesthesia technique may prove helpful for fast-track eligibility of these patients.  

remifentanil, fentanyl, isoflurane, general anesthesia, uro-logic procedures, outpatient surgery, Aldrete score, recovery time, disc-harge time

1. Kaye KW. Changing trends in urology practice: increasing outpatient surgery. Austr New Zealand J Surg 1995;65(1):31-4.

2. Kahn RL. Outpatient endourlogic procedures. Urologic Clin North Amer 1987;14(1):77-89.

3. Westmoreland CL, Hoke JF, Sebel PS, Hug CC Jr, Muir KT. Pharmacokinetics of remifentanil (GI87084B) and its major metabolite (GI90291) in patients undergoing elective inpatient surgery. Anesthesiology 1993;79:893-903.

4. Glass PS, Hardman D, Kamiyama Y, Quill TJ, Marton G, Donn KH, et al. Preliminary pharmacokinetics and pharmacodynamics of an ultra-short-acting opioid: L remifentanil (GI87084B). Anesth Analg 1993;77(5):1031-40.

5. Burkle H, Dunbar S, Van Aken H. Remifentanil: a novel, short-acting, mu-opioid. Anesth Analg 1996;83(3):646-51.

6. Lange E, Kapila A, Shlugman D, Hoke JF, Sebel PS, Glass PSA. Reduction of isoflurane minimal alveolar concentration by remifentanil. Anesthesiology 1996;85(4):721-8.

7. Gupta A, Larsen LE, Sjoberg F, Lindh ML, Lennmarken C. Thiopentone or propofol for induction of isoflurane-based anesthesia for ambulatory surgery? Acta Anaesthesiol Scand 1992;36:670-4.

8. Thompson JP, Hall AP, Russell J, Cagney B, Rowbotham DJ. Effect of remifentanil on the hemodynamic response to orotracheal intuba-tion. Br J Anaesth 1998;80(4):467-9.

9. Hirsch J. Impact of postoperative nausea and vomiting in the surgical setting. Anesthesia 1994;49:30-3.

10. Carroll NV, Miederhoff PA, Cox FM, Hirsch JD. Costs incurred by outpatient surgical centers in managing nausea and vomiting. J Clin Anesth 1994;6(5):364-9.

11. Johnston R, Noseworthy T, Anderson B, Konopad E, Grace M. Propofol versus thiopental for outpatient anesthesia. Anesthesiology 1987;67(3):431-3.

12. Korttila K, Nuotto EJ, Lichtor JL, Ostman PL, Apfelbaum J, Rupani G. Clinical recovery and psychomotor function after brief anesthesia with propofol or thiopental. Anesthesiology 1992;76:676-81.

13. Sengupta P, Plantevin OM. Nitrous oxide and day-case laparoscopy: effects on nausea, vomiting and return to normal activity. Br J Anaesth 1988;60:570-3.

14. Sukhani R, Lurie J, Jabamoni R. Propofol for ambulatory gynecologic laparoscopy: does omission of nitrous oxide alter postoperative emetic sequel and recovery? Anesth Analg 1994;78(4):831-5.