title: Caudal clonidine prolongs analgesia from caudal S(+)-ketamine in children.
abstract: We performed a prospective randomized double-blinded study to test preservative-free S(+)-ketamine alone or in combination with clonidine for intra- and postoperative caudal blockade in pediatric surgery over a 24-h period. Fifty-three children (1-72 mo) scheduled for inguinal hernia repair were caudally injected with either S(+)-ketamine 1 mg/kg alone (Group K) or with additional clonidine (Group C1 = 1 microg/kg; Group C2 = 2 microg/kg) during sevoflurane anesthesia via a laryngeal mask. Intraoperative monitoring included heart rate, blood pressure, and pulse oximetry; postoperative monitoring included a pain discomfort scale and a sedation score. No additional analgesic drugs were required during surgery. The mean duration of postoperative analgesia was 13.3 +/- 9.2 h in Group K, 22.7 +/- 3.5 h in Group C1, and 21.8 +/- 5.2 h in Group C2 (P < 0.0001, Group K versus other groups). Groups C1 and C2 received significantly fewer analgesics in the postoperative period than Group K (15% and 18% vs 63%; P < 0.01). The three groups had similar postoperative sedation scores. We conclude that the combination of S(+)-ketamine 1 mg/kg with clonidine 1 or 2 microg/kg for caudal blockade in children provides excellent analgesia without side effects over a 24-h period.
  
  
  CONCLUSIONS
  Caudally administered preservative-free S(+)-ketamine combined with 1 or 2 microg/kg clonidine provides excellent perioperative analgesia in children and has minimal side effects.
authors.affiliation: Department of Anesthesia and Intensive Care Medicine, University of Vienna, Austria.
authors.forename: Helmut
authors.initials: H
authors.lastname: Hager
authors.forename: Peter
authors.initials: P
authors.lastname: Marhofer
authors.forename: Christian
authors.initials: C
authors.lastname: Sitzwohl
authors.forename: Leo
authors.initials: L
authors.lastname: Adler
authors.forename: Stephan
authors.initials: S
authors.lastname: Kettner
authors.forename: Margot
authors.initials: M
authors.lastname: Semsroth
mesh_terms: D000698:Analgesia; D000763:Anesthesia, Caudal; D002648:Child; D002675:Child, Preschool; D003000:Clonidine / Q000008:administration & dosage*; D004311:Double-Blind Method; D006801:Humans; D007223:Infant; D007649:Ketamine / Q000008:administration & dosage*; D011446:Prospective Studies
chemical_list: D007649:Ketamine; D003000:Clonidine