Ansermino Mark, Basu Rahul, Vandebeek Christine, Montgomery Carolyne
Department of Anesthesia, British Columbia's Children's Hospital, Vancouver, Canada.
Paediatr Anaesth. 2003 Sep;13(7):561-73. doi: 10.1046/j.1460-9592.2003.01048.x.
Caudal epidural injection with local anaesthetics is a popular regional technique used in infants and children. A disadvantage of caudal blockade is the relatively short duration of postoperative analgesia. Opioids have traditionally been added to increase the duration of analgesia but have been associated with unacceptable side-effects. A number of nonopioid additives have been suggested to increase the duration of analgesia.
A systematic review was conducted to identify randomized control trials comparing the use of local anaesthetic to local anaesthetic with nonopioid additives for caudal blockade in children. The increase in duration of analgesia and side-effects were compared.
The addition of clonidine to the local anaesthetic solution produces an increase in the duration of analgesia following caudal blockade in children (pooled weighted mean difference of 145 min with 95% confidence interval of 132-157 min). Side-effects include sedation and the potential for neonatal respiratory depression. Ketamine and midazolam further increase the duration of analgesia, however, the potential for neurotoxicity remains a concern.
The evidence examined shows an increased duration of analgesia with clonidine, ketamine and midazolam. However, we are not convinced that the routine use of these adjuvants in the setting of elective outpatient surgery shows improved patient outcome. It is unclear if the potential for neurotoxicity is outweighed by clinical benefits. Further testing, including large clinical trials, is required before recommending routine use of nonopioid additives for caudal blockade in children.
在婴幼儿中，骶管硬膜外注射局部麻醉剂是一种常用的区域麻醉技术。骶管阻滞的一个缺点是术后镇痛时间相对较短。传统上会添加阿片类药物以延长镇痛时间，但会产生难以接受的副作用。有人提出使用多种非阿片类添加剂来延长镇痛时间。
进行了一项系统评价，以确定比较局部麻醉剂与添加非阿片类添加剂的局部麻醉剂用于儿童骶管阻滞的随机对照试验。比较了镇痛时间的延长和副作用情况。
在局部麻醉剂溶液中添加可乐定可延长儿童骶管阻滞后的镇痛时间（合并加权平均差为145分钟，95%置信区间为132 - 157分钟）。副作用包括镇静以及新生儿呼吸抑制的可能性。氯胺酮和咪达唑仑可进一步延长镇痛时间，然而，神经毒性的可能性仍然令人担忧。
所审查的证据表明，可乐定、氯胺酮和咪达唑仑可延长镇痛时间。然而，我们不相信在择期门诊手术中常规使用这些佐剂能改善患者预后。目前尚不清楚神经毒性的可能性是否被临床益处所抵消。在推荐常规使用非阿片类添加剂用于儿童骶管阻滞之前，需要进行进一步测试，包括大型临床试验。
