To find alternatives to caudal analgesia that could be more safe and effective and to demonstrate the analgesic efficacy of topical ketamine.

The most commonly performed inguinal surgeries in children include inguinal hernia repair with or without orchidopexy (orchiopexy). Eighty children aged 6 months to 6 yr of ASA physical status I or II, undergoing elective unilateral inguinal herniotomy will be included. In caudal group, patients will receive a mixture of 0.5 mg/ kg ketamine in 1 ml/kg bupivacaine 0.25% (maximum volume = 20 ml) by caudal route after anesthesia and before start of surgery. In topical group, at the end of the procedure, after identification and ligation of the hernial sac, a mixture of 0.5 mg/ kg ketamine in 0.3 ml/kg bupivacaine 0.25% will be sprayed around the spermatic cord and upon the ilioinguinal nerve in a fan shaped manner by the surgeon. The primary outcome measure will be the time to first request for analgesia. Secondary outcome measures will include the number of analgesic doses required in the first 24 h postoperative, pain scores, sensory and motor block, agitation scores, parent satisfaction and adverse effects in the first 48h postoperative.

Inclusion Criteria:

1. age (6 months to 6 years)
2. ASA physical status I or II.
3. Operation: elective unilateral inguinal herniotomy.

Exclusion Criteria:

1. A history of developmental delay or mental retardation,
2. Known or suspected coagulopathy,
3. Known allergy to any local anaesthetic,
4. Known congenital anomaly of the spine or signs of spinal anomaly,
5. Infection at the sacral region.