efficacy and patient satisfaction of remifentanil as patient-maintained tci in comparison with morphin bolus pca after major abdominal surgery

U Mohl, M Zammert, C Zimmermann, J Flaschar, S Schraag

Department of Anaesthesiology, University of Ulm, D-89075 Ulm, Germany

Background and Goal of study: Remifentanil is increasingly used as the analgesic component during general anaesthesia (1). However, the appropriate transition to post-operative analgesia remains a challenge. We tested the efficacy and patient satisfaction of a patient-maintained Remifentanil (REMI) target-controlled infusion (TCI) (2) against standard Morphine PCA (MO) after major abdominal surgery.

Materials and Methods: After obtained institutional ethic`s committee approval and written informed consent, 62 male premedicated patients undergoing elective radical prostatectomy having Propofol-Remifentanil anaesthesia were studied. They were allocated randomly in three groups to receive postoperative REMI TCI-PCA (Group 1), MO PCA, with additional priming of either a low-dose bolus (0.1 mg kg^-1, Group 2), or a high-dose bolus (0.25 mg kg^-1, Group 3) 15min prior to end of surgery. Study design was double-blind and double-dummy, so every patient demand of a single button push simultaneously operated two pumps, one with study drug, the other with saline. The level of analgesia was documented on a 11-point visual analogue scale (VAS), whereas patient satisfaction was assessed by means of a 5-point linear score (1=excellent, 4= poor) and the Zerssen self-rating mood inventory. Observations were carried out until 24 hours after end of surgery. Statistical analysis was provided by the nonparametric Kruskal-Wallis test with a significance level of a=0.05.

Results and Discussion: Recovery milestones and patient ratings are listed in the table below (Mean values with 95% CI):

GROUP	REMI PCA-TCI	MO PCA low	MO PCA high	p-value
Dt RR >10 (min)	12.5 (7.1-17.9)	8.3 (5.2-11.4)	16.1 (7.4-24.7)	0.21
Dt VAS <3 (min)	18.2 (7.0-29.3)	29.7 (8.9-50.6)	20.6 (15.1-26.1)	0.98
Mean VAS score (24 h)	1.0 (0.1-2.1)	1.4 (0.2-2.6)	1.5 (0.3-2.8)	0.47
Satisfaction score (range)	2 (1-3)	1.75 (1-3)	2 (1-3)	n.s.
Zerssen mood inventory (0-56)	17.1 (12.6-21.5)	9.3 * (5.3-13.2)	20.6 (15.1-26.1)	0.004

The MO low group had the largest variation in onset of adequate analgesia and the lowest self-rating score for postoperative mood

Conclusion: Our preliminary data suggest that patient-maintained REMI TCI is equally effective to provide satisfactory analgesia and thus may be an attractive alternative to standard Morphine bolus PCA after REMI based anaesthesia.

References:

[1] Suttner S et al. Anesthe Analg 1999; 88:77-82.

[2] Schraag S, et al: Br J Anaesth 1999; 76:795-801.