Abstract
Caudal analgesia for surgical procedures was performed on 65 children, newborn to 8 years of age. A 0.25 per cent solution of bupivacaine was used for infants less than 5kg in body weight, 0.5 per cent solution of bupivacaine for larger children.
The segmental dose requirements for caudal analgesia increased with increases in body weight (r=0.97, p<0.001). The resultant regression equation stated that the dose requirements (ml/spinal segment) of bupivacaine were equal to [0.050 x body weight (kg)-0.025]. The mean maximum concentration of bupivacaine were 0.62±0.24 (mean ±S.D.)μg/ml and occurred at 30 and 45 minutes after injection of bupivacaine 3.7mg/kg with epinephrine 1:200, 000. These blood concentrations were measured by venous and whole blood samples. The patients had adequate analgesia for 2.5 hours through the surgical procedures and managed whth incremental intravenous administration of thiamylal 3mg/kg.
The dose requirements of bupivacaine for caudal analgesia in children are less than those of lidocaine calculated previously. I recommend the caudal extradural administration of bupivacaine for long-lasting operation and postoperative pain relief.
