Epidural Clonidine or Sufentanil for Intraoperative and Postoperative Analgesia

Abstract

This study contrasts the efficacy and side effects of epidural clonidine and sufentanil in the perioperative period.Using a randomized, prospective, double-blind study design, 40 patients undergoing abdominal surgery under propofol/nitrous oxide anesthesia were enrolled. Before anesthesia, an epidural catheter was inserted at the L1-L2 interspace. At induction of anesthesia, the patients received epidurally either clonidine (4 micro gram/kg in 10 mL) infused in 20 min followed by a 2-micro gram centered dot kg-1 centered dot h-1 infusion (5 mL/h) during 12 h (Group 1) or sufentanil (0.5 micro gram/kg in 10 mL) in 20 min followed by a 0.25-micro gram centered dot kg-1 centered dot h-1 infusion (5 mL/h) during 12 h (Group 2). Intraoperatively, increases in arterial blood pressure and heart rate not responding to propofol bolus (0.5 mg/kg) were treated with a bolus of intravenous (IV) sufentanil 0.035 micro gram/kg. Postoperatively, IV sufentanil boluses (5 micro gram) were given through a patient-controlled analgesia (PCA) device. Postoperative analgesia was assessed by recording the IV PCA sufentanil requirements and the patients' visual analog scale (VAS) at 3, 6, 12, 18, 24, 36, and 48 h. Sedation analog scales and side effects were also recorded. Plasma clonidine and sufentanil concentrations were measured after 20 min and 6, 12, and 24 h. The number of reinjections of propofol (n = 1.6 +/- 1.6 in Group 1 vs 6.5 +/- 4.0 in Group 2) and of IV sufentanil (n = 0.6 +/- 0.8 in Group 1 vs 3.8 +/- 3.7 in Group 2) was significantly reduced (P < 0.001) in the epidural clonidine group. In the early post-operative period, pain scores and rescue analgesic requirements were very low in both groups. After discontinuation of the epidural infusions, reduced PCA requirements and the better VAS scores were still noted in Group 1 (80.5 +/- 55.7 micro gram IV sufentanil in Group 1 vs 142 +/- 87 micro gram in Group 2; P < 0.05). There was no difference in sedation scores. Epidural clonidine and sufentanil only moderately affected heart rate and blood pressure. Two instances of awareness in Group 1 and one episode of respiratory depression in Group 2 were reported. Epidural clonidine improved intraoperative hemodynamic stability when compared with epidural sufentanil. Both substances provided reliable postoperative analgesia. A longer lasting residual analgesic effect was demonstrated after the use of epidural clonidine. Both substances showed different but potentially worrying side effects. (Anesth Analg 1995;81:1154-62)