Patients with hypertension exhibit reduced heart rate control during the recovery period after elective surgery. Clonidine prevents this reduction in heart rate control. This may represent a basis for the improved circulatory stability seen with perioperative administration of clonidine.

Background. Sufentanil and remifentanil are characterized by two different pharmacokinetic pro®les. The aim of this study was to compare the effects of sufentanil and remifentanil administered using target-controlled infusion (TCI) on recovery and postoperative analgesia after major abdominal surgery.Methods. Thirty adult patients scheduled for open colorectal surgery were included in a prospective, randomized study. Sufentanil TCI (sufentanil group) or remifentanil TCI (remifentanil group) was administered during surgery. In the remifentanil group, 30 min before the anticipated end of surgery, morphine 0.15 mg kg ±1 was administered i.v. In the sufentanil group, an effect-site concentration of 0.25 ng ml ±1 was targeted at extubation. In both groups, postoperative pain was controlled by titration of i.v. morphine and then patient-controlled analgesia with morphine.Results. The extubation time was similar in the two groups (mean (SD) 13 ( 6) and 14 (6) min in the sufentanil and remifentanil groups respectively). Visual analogue scale scores were signi®cantly greater during the ®rst 2 h after tracheal extubation in the remifentanil group than in the sufentanil group. The time to ®rst analgesic request in the postanaesthesia care unit was signi®cantly longer in the sufentanil group than in the remifentanil group (55 (64) (range 2±240) vs 11 (7) (1±29) min; P<0.001). The cumulative morphine dose for titration was signi®cantly greater in the remifentanil group (P<0.01). The cumulative morphine dose used during titration and patient-controlled analgesia was signi®cantly greater in the remifentanil group 4, 12 and 24 h after extubation (P<0.05). Conclusion.TCI sufentanil (0.25 ng ml ±1 effect-site concentration at extubation) is more effective than the intraoperative combination of remifentanil TCI infusion with morphine bolus (0.15 mg kg ±1 ) for postoperative pain relief after major abdominal surgery and does not compromise extubation and recovery.

At a given dose, sufentanil inhibited shivering 2,800 times better than meperidine. However, the equianalgesic ratio of these drugs is approximately 4,900. That is, meperidine inhibited shivering better than would be expected based on the equianalgesic potency ratio. These data are thus consistent with clinical observations suggesting that meperidine indeed possesses special antishivering activity.

No abstract

No pharmacokinetic data are available with respect to the plasma concentrations and fentanyl or sufentanil during epidural administration in children. This double-blind randomized study included 12 children (5-12 yr). Patients in group F were given an epidural loading dose of fentanyl 1.5 micrograms kg-1 and in group S sufentanil 0.6 microgram kg-1. Both groups then received a continuous epidural infusion of bupivacaine 5 mg kg-1 day-1 with either fentanyl 5 micrograms kg-1 day-1 or sufentanil 2 micrograms kg-1 day-1. An epidural PCA system was also given to the children (bolus: bupivacaine 0.2 mg kg-1 and fentanyl 0.2 microgram kg-1 or sufentanil 0.08 microgram kg-1). Maximal median concentrations of plasma (0.117-0.247 ng ml-1 for fentanyl and 0.027-0.074 ng ml-1 for sufentanil) were reached approximately 30 and 20 min respectively after the loading doses. These values were similar to those measured after 48 h.