[Influence of a child's age on anesthetic technique based on analgesia with remifentanil].

AIMS: To study the possible pharmacodynamic differences in children under anesthesia based on remifentanil.

METHODS: This multicenter observational study enrolled 275 patients scheduled for minor pediatric surgery (herniorrhaphy, prepuceplasty, and plastic surgery). The children were grouped by age: 1-3 years, 4-7 years, 8-12 years. Premedication was with midazolam, induction with sevoflurane or propofol, and maintenance with sevoflurane 0.5%-0.8%, N2O/O2 30%/70%, and remifentanil 0.25 microg/kg/min. Postoperative analgesia (metamizol, morphine or regional block) was administered at least 30 minutes before the end of surgery.

RESULTS: No differences were found between age groups with regard to remifentanil requirements, end tidal concentrations of sevoflurane, or mean times until spontaneous ventilation or extubation. Nor were there differences in the percentages of complications (5.4%), of which 4 were cases of intense postoperative muscular rigidity, or in the incidence of nausea-vomiting (3.4%). The quality of recovery from anesthesia (Aldrete test) was better in the 8-12-year-old group (P < 0.05), however, while agitation (Postoperative Agitation Score) and pain (visual analog scale or observational scales) were greater in the group of 1-3-year-olds (P < 0.05). The evaluation of the technique by participating caregivers was excellent for 20%, very good for 41%, good for 29%, adequate for 8% and poor for 2% of the cases.