[Perioperative analgesia with continuous epidural infusion of morphine combined with clonidine in children undergoing abdominal surgeries.].

BACKGROUND AND OBJECTIVES The present study was developed to evaluate the analgesic effects of the epidural administration of a combination of morphine and clonidine, whose efficacy has been demonstrated in adults, on the consumption of isoflurane and postoperative consumption of analgesics in children. METHODS Twenty-six children scheduled for intra-abdominal surgeries were randomly divided in two groups. Both groups received an epidural bolus of morphine (8 microg.kg-1) and clonidine (0.8 microg.kg-1) before the surgery, followed by the continuous infusion of clonidine (0.12 microg.kg-1.h-1) plus morphine (1.2 microg.kg-1.h-1) in Group I, and twice those dosages in Group II, during 24 hours. Inspiratory concentrations of isoflurane were measured during the surgery, as well as the number of doses (1 mg.kg-1) of tramadol during 24 hours in the postoperative period. RESULTS The concentrations of isoflurane were significantly smaller after 60 and 90 minutes than the concentrations before the incision in Groups II and I, respectively, but those differences were not statistically significant. The consumption of tramadol was significantly lower in Group II, and 7 (53.8%) patients in this group did not need rescue analgesia, but we observed an increase in the incidence of sedation and hypotension. Respiratory depression was not observed in either group. CONCLUSIONS Epidural infusion of low doses of clonidine combined with morphine reduced the intraoperative need of isoflurane and postoperative analgesia.