To establish whether caudal with ketamine or penile block provide superior postoperative analgesia for paediatric circumcision.

This was a single centre, prospective, randomized, controlled, double-blind trial. Forty males (aged between 18 months and 16 yr) were randomized to receive either a penile block using 0.25 mL kg−1 0.5% bupivacaine (Group P), or a caudal block using 0.5 mL kg−1 0.25% bupivacaine with 0.5 mg kg−1 ketamine (Group C). All of them were given a standard anaesthetic and rectal paracetamol 40 mg kg−1 and diclofenac 1–1.5 mg kg−1. Postoperative pain scores were assessed in recovery and the time to first analgesia, micturition and walking were recorded.

There were no failures in either group. The time to first analgesia was longer in Group C (C median = 459 min, interquartile range 374–553 min; P median = 374 min, interquartile range 224–507 min; P < 0.05). There was a delay in time to walking in Group C (C median = 162 min, interquartile range 119–208 min; P median = 120 min, interquartile range 92–132 min; P < 0.05). There was no difference between the groups in time to waking or micturition, or the incidence of vomiting, abnormal behaviour or bleeding.

Caudal bupivacaine with ketamine and penile block both provide effective postoperative analgesia for circumcision when given with non-steroidal anti-inflammatory drugs. This study shows that caudal bupivacaine with ketamine provides a longer duration of analgesia than penile block, but also causes delay in walking.

Although the association of tissue coring and development of epidermoid tumour has been proposed, the extent and frequency of such coring is still controversial and the viability of carried cells has not been substantiated. In the present study, we used an experimental model without needle removal to investigate the incidence of tissue coring using two different needle types.

We inserted 22-G caudal (n = 34) or 22-G hollow (n = 25) needles to the tumour-free areas of fresh modified mastectomy specimens. The specimen was stretched and needles were inserted perpendicular to the skin and forced to penetrate the full thickness of the specimen. Without removing the needle, the needle cavity was then washed with 2 mL of RPMI 1640 with l-Glutamine and the washings were collected in a 15-mL falcon tube. The tubes were sealed and labelled and processed to obtain cytologic preparations. The slides were evaluated under a light microscope.

A high rate of epithelial cell transportation was noted. All the carried cells were stratum corneum cells with no nucleus. No nucleated cells were seen. The incidence of carried cells was 64.7% and 72.0% in the caudal and hollow needle groups, respectively (P > 0.05).

Only cells from the outermost layer, stratum corneum, which is made of dead flat skin cells, were transported with needle puncture. The risk of epidermoid tumour development after regional anaesthesia must therefore be low. The incidence of transporting non-nucleated stratum corneum cells was similar between hollow and caudal needles.

Several studies showed that single analgesic modality management can attenuate perioperative stress, but little is known about the effect of multimodal analgesia on catecholamine responses to surgical trauma in children.

Fifty children (American Society of Anesthesiologists Grade I or II) were randomly allocated to one of two groups: one received general anaesthesia and a caudal block (control group), and one group was given general anaesthesia, caudal block and intravenous (i.v.) fentanyl 2 μg kg−1 (fentanyl group). Plasma epinephrine and norepinephrine concentrations were measured three times during the perioperative period: at induction time (T0), at the end of surgery (T1) and when the children were fully awake in the postanaesthesia care unit (T2).

There was a significant reduction in the catecholamine levels in the two groups when (T1) and (T2) were compared with T0. When plasma epinephrine levels (at T0, T1 and T2) between the two groups were compared, a statistically significant reduction at T2 was obtained in the fentanyl group, when compared with the control group. However, plasma norepinephrine levels showed no statistically significant difference between the two groups (at T0, T1 and T2).

These findings suggest that the multimodal analgesic approach of adding i.v. low-dose fentanyl to a caudal block may decrease the plasma epinephrine release in children undergoing inguinal herniotomy.