Anesthesiology and Pain Medicine, University of Toronto, Toronto, Ontario, Canada.
Anesthesiology and Pain Medicine and the Ottawa Hospital Research Institute, University of Ottawa, Ottawa, Ontario, Canada.
Reg Anesth Pain Med. 2020 Sep;45(9):733-739. doi: 10.1136/rapm-2020-101603. Epub 2020 Jul 22.
Ambulatory anorectal surgery requires an anesthetic of short duration but profound depth. Saddle block anesthesia (SBA) can provide dense sacral anesthesia with minimal motor blockade, but the ideal local anesthetic agent remains undefined. This systematic review aims to identify the optimal SBA regimen for ambulatory anorectal surgery.
We sought randomized trials examining SBA for ambulatory anorectal surgery and stratified patients into four subgroups according to local anesthetic type and dose: (1) longer acting, higher dose; (2) longer acting, lower dose; (3) shorter acting, higher dose; and (4) shorter acting, lower dose. Longer acting agents included bupivacaine and levobupivacaine; shorter acting agents included chloroprocaine, mepivacaine, and prilocaine. Lower dose was defined as ≤5 mg and ≤20 mg for longer and shorter acting local anesthetics, respectively. The primary outcome was time to discharge; secondary outcomes included times to sensory and motor block regression, urine voiding, and ambulation, as well as block success.
A total of 11 trials (1063 patients) were included. Overall study quality and reporting consistency was poor. Doses ranged from 1.5-7.5 mg to 3-30 mg of longer and shorter acting local anesthetics, respectively. Hyperbaric local anesthetics were used in eight trials (953 patients, 86%). The median time to discharge appeared similar across all subgroups with an overall time of 182 (IQR 102) min. The use of long-acting, lower dose regimens was associated with a faster median time to motor block regression. Block success approached 99% among all trials.
There is presently insufficient qualitative and quantitative evidence to identify an optimal SBA regimen for ambulatory anorectal surgery. Nonetheless, we found that doses as low as 1.5 and 3 mg of longer and shorter acting hyperbaric local anesthetics, respectively, can achieve effective and reliable SBA with timely hospital discharge. Despite similar discharge times, longer acting, lower dose local anesthetics may produce faster motor block regression following SBA for ambulatory anorectal surgery.
门诊肛门直肠手术需要持续时间短但深度深的麻醉。鞍区阻滞麻醉（SBA）可以提供密集的骶骨麻醉，运动阻滞最小，但理想的局部麻醉剂仍未定义。本系统评价旨在确定用于门诊肛门直肠手术的最佳 SBA 方案。
我们寻找了检查鞍区阻滞麻醉用于门诊肛门直肠手术的随机试验，并根据局部麻醉剂的类型和剂量将患者分为四组：（1）作用时间长，剂量高；（2）作用时间长，剂量低；（3）作用时间短，剂量高；和（4）作用时间短，剂量低。长效麻醉剂包括布比卡因和左旋布比卡因；短效麻醉剂包括氯普鲁卡因、甲哌卡因和丙胺卡因。较低剂量定义为较长和较短作用时间的局部麻醉剂分别为≤5mg 和≤20mg。主要结局是出院时间；次要结局包括感觉和运动阻滞消退、排尿和行走时间，以及阻滞成功率。
共纳入 11 项试验（1063 例患者）。整体研究质量和报告一致性较差。剂量范围从 1.5-7.5mg 到 3-30mg 的较长和较短作用时间的局部麻醉剂。在八项试验（953 例患者，86%）中使用了超高压局部麻醉剂。所有亚组的中位出院时间似乎相似，总体时间为 182（IQR 102）分钟。使用长效、低剂量方案与中位运动阻滞消退时间较快相关。所有试验的阻滞成功率均接近 99%。
目前缺乏定性和定量证据来确定门诊肛门直肠手术的最佳 SBA 方案。尽管如此，我们发现，分别使用低至 1.5mg 和 3mg 的长效和短效超高压局部麻醉剂，即可实现有效的 SBA 和及时出院。尽管出院时间相似，但长效、低剂量局部麻醉剂在门诊肛门直肠手术后进行 SBA 时可能会更快地产生运动阻滞消退。
