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Midazolam for caudal analgesia in children: comparison with caudal bupivacaine


In a randomized, double-blind study we have examined the analgesic efficacy of caudal administration of midazolam, bupivacaine, or a mixture of both drugs in 45 children, undergoing inguinal herniotomy. They were allocated randomly into three groups (n = 15 in each) to receive a caudal injection of either 0.25% bupivacaine 1 ml · kg−1 with or without midazolam 50 μg · kg−1 or midazolam 50 μg · kg−1 with normal saline 1 ml · kg−1. There were no differences in quality of pain relief, postoperative behaviour or analgesic requirements between the midazolam group and the other two groups. Times to first analgesic administration (paracetamol suppositories) were longer (P < 0.001) in the bupivacaine-midazolam group than in the other two groups. Further, the bupivacaine-midazolam group received fewer (P < 0.05) doses of paracetamol than the bupivacaine group. Side effects such as motor weakness, respiratory depression or prolonged sedation were not observed in patients who received caudal epidural midazolam only. We conclude that caudal midazolam in a dose of 50 μg · kg−1 provides equivalent analgesia to bupivacaine 0.25%, when administered postoperatively in a volume of 1 ml · kg−1 for children following unilateral inguinal hemiotomy.


Cette étude randomisée et à double aveugle évalue l’efficacité analgésique du midazolam, de la bupivacaïne ou du mélange de ces deux produits administrés par la voie caudale chez 45 enfants soumis à une herniotomie inguinale. Ils sont répartis en trois groupes (n = 15) pour recevoir une injection caudale contenant soit de bupivacaïne 0,25% 1 ml · kg−1 avec ou sans midazolam 50 μg · kg−1, soit de midazolam 50 μg · kg avec du soluté physiologique 1 ml · kg−1. Nous ne notons pas de différence pour ce qui est de la qualité de l’analgésie, du comportement postopératoire et des besoins en analgésiques entre le groupe midazolam et les deux autres groupes. L’intervalle précédant la première administration d’un analgésique (du paracétamol en suppositoire) est plus long (P < 0,001) pour le groupe bupivacaïne-midazolam que pour les deux autres groupes. De plus, nous administrons moins souvent (P < 0,05) de paracétamol au groupe bupivacaïne-midazolam qu’an groupe bupivacaïne. Nous concluons que le midazolam caudal à la dose de 50 μg · kg−1 produit une analgésie équivalente à la bupivacaïne 0,25% lorsqu’il est administré à des enfants à la période postopératoire dans un volume de 1 ml · kg−1 après une herniotomie inguinale.


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Correspondence to Mohamed Naguib.

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Naguib, M., El Gammal, M., Elhattab, Y.S. et al. Midazolam for caudal analgesia in children: comparison with caudal bupivacaine. Can J Anaesth 42, 758–764 (1995).

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Key words

  • analgesia: paediatric, postoperative
  • anaesthetic techniques: caudal
  • anaesthetic, local: bupivacaine
  • hypnotics: benzodiazepines, midazolam