[Postoperative analgesia using caudal morphine in pediatric surgery: randomized double-blind study compared with bupivacaine]. / Analgesia postoperatoria con morfina por vía caudal en cirugía pediátrica: estudio aleatorio y a doble ciego comparado con bupivacaína.

Morphine and bupivacaine have been administered caudal via to 28 children between 2 and 12 years old for the postoperative pain treatment. All of them were submitted to general anesthesia and randomly divided into 3 groups depending on the drug administered caudal via. a) Morphine group (n = 10): morphine chlorhydrate 50 micrograms/kg (0.5 ml/kg of morphine solution 100 micrograms/ml). b) Bupivacaine group (n = 10): bupivacaine 0.5%, 2.5 mg/kg. c) Control group (n = 8): no drug administered. Pain evaluation was made on the basis of physiological and clinical data. In the morphine group, the postoperative time until analgesia was required 20 +/- 5 hours and analgesia has been significantly better (p less than 0.001) than bupivacaine and control group. The number of analgesic drug needed during the postoperative 24 first hours was also less in morphine group. No differences on postoperative complications were seen among the 3 groups and no case of respiratory depression was observed. It is concluded that epiduro-caudal morphine provides effective and prolonged analgesia and can be safely used for postoperative pain treatment in pediatric urologic surgery. However, we believe, that larger series of patients will provide better information of its efficacy and other side effects.