The efficacy of caudal ropivacaine 1, 2 and 3 mg x l(-1) for postoperative analgesia in children.
BACKGROUND
The aim of this double blind, randomized, comparative study was to assess the analgesic efficacy and incidence of motor block after caudal block using three different concentrations of ropivacaine, 1, 2 and 3 mg x l(-1), in children 4-12-year-old.


METHODS
One hundred and ten children ASA I-II, scheduled for inguinal surgery, were included in the study. After induction of a standardized general anaesthetic technique, all patients received 1 ml x kg(-1) of the ropivacaine solution for a caudal block and were assessed for 8 h after the injection.


RESULTS
The ropivacaine was well tolerated in all patients. Median time to treatment with analgesics was 3.3, 4.5 and 4.2 h in the 1, 2 and 3 mg x ml(-1) groups, respectively. During the first 4 h, the pain scores for both a 6-graded faces scale and a 4-graded observer scale were higher in the 1 mg x ml(-1) group than the 3 mg x ml(-1) group. The median sensory block reached T12 in all groups 1 h after the caudal block. Thereafter, the speed of regression was correlated with the ropivacaine concentration. In the patients with a sensory block from T12 and above, the median time to treatment with analgesics was longer than in the children with a sensory block below T12. The incidence of motor block was 28% in the 3 mg x ml(-1) group in comparison with 0 and 13% in the 1 and 2 mg x ml(-1) groups.


CONCLUSIONS
It was concluded that 1 ml x kg(-1) of ropivacaine 2 mg x ml(-1) for caudal block provided satisfactory postoperative pain relief after inguinal surgery in 4-12-year-old children. Ropivacaine 1 mg x ml(-1) showed less efficacy while the use of ropivacaine 3 mg x ml(-1) was associated with a higher incidence of motor block with minimal improvement in postoperative pain relief.
Bosenberg
A
A
Department of Anaesthesia, University of Natal, Durban, South Africa. bosie@nu.ac.za
Thomas
J
J
Lopez
T
T
Lybeck
A
A
Huizar
Karin
K
Larsson
L E
LE
D000577:Amides / Q000008:administration & dosage; D000763:Anesthesia, Caudal; D000768:Anesthesia, General; D002648:Child; D002675:Child, Preschool; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D009407:Nerve Block; D010147:Pain Measurement; D010149:Postoperative Pain / Q000628:therapy*; D000077212:Ropivacaine
D000577:Amides; D000077212:Ropivacaine