Department of Small Animal Clinical Science, University of Liverpool, Liverpool, UK.
Department of Small Animal Clinical Science, University of Liverpool, Liverpool, UK.
Vet Anaesth Analg. 2021 Jul;48(4):577-584. doi: 10.1016/j.vaa.2020.11.009. Epub 2021 Mar 19.
To describe dye distribution and spinal nerve involvement after a simulated erector spinae plane (ESP) block performed on fresh equine cadavers.
Experimental cadaver study.
A group of 11 adult equine cadavers.
The spinal region surrounding the sixteenth thoracic vertebra (Th16) of one cadaver was removed and underwent magnetic resonance imaging. In 10 adult equine cadavers [body weight, 549 ± 58 kg (mean ± standard deviation)], 0.2 mL kg of a 50:1 2% lidocaine/dye solution was injected bilaterally (n = 20 injections) into the fascial plane between the transverse process of Th16 and the erector spinae muscles. An in-plane ultrasound-guided technique with a convex transducer was used to guide injection. Dissection was performed immediately following injection. The craniocaudal and lateral extent of dye distribution was measured (cm) and the number of vertebral bodies involved were counted (n = 20). Abdominal and thoracic cavities as well as the epidural space were also examined for presence of dye (yes/no) (n = 20). Further dissection was performed to evaluate if staining of the dorsal and ventral rami of the spinal nerves and sympathetic chain occurred (n = 14).
The thoracolumbar fascia was stained in 17/20 (85%) injections and three injections terminated intramuscularly. Multisegmental staining of the dorsal rami was observed in the 14 injections in which staining was evaluated. Ventral rami staining was observed in 3/14 injections where staining was evaluated. Epidural migration was observed in 4/20 (20%) injections. No evidence of dye was found in the thoracic and abdominal cavities or on the sympathetic chain.
The ESP block may prove beneficial to desensitize structures innervated by the dorsal rami of the thoracic spinal nerves. Further investigation is necessary to evaluate complications caused by epidural contamination.
描述在新鲜马尸体上模拟竖脊肌平面（ESP）阻滞后的染料分布和脊神经受累情况。
实验性尸体研究。
一组 11 头成年马尸体。
从一具尸体的第十六胸椎（Th16）周围的脊柱区域进行磁共振成像。在 10 头成年马尸体[体重，549 ± 58 kg（平均值 ± 标准差）]中，双侧（n = 20 次注射）在 Th16 横突和竖脊肌之间的筋膜平面注射 0.2 mL kg 的 50:1 2%利多卡因/染料溶液。使用平面内超声引导技术和凸阵换能器引导注射。注射后立即进行解剖。测量染料分布的头尾侧和外侧范围（cm）并计数受累的椎体数（n = 20）。还检查了腹部和胸部腔以及硬膜外腔是否存在染料（是/否）（n = 20）。进一步解剖以评估是否发生脊神经背侧和腹侧支以及交感链的染色（n = 14）。
在 20 次注射中的 17 次（85%）中染色了胸腰筋膜，3 次注射终止于肌肉内。在进行评估的 14 次注射中观察到背侧支的多节段染色。在进行评估的 3 次注射中观察到腹侧支染色。在 4 次注射（20%）中观察到硬膜外迁移。在胸腔和腹腔或交感链上未发现染料。
ESP 阻滞可能有益于使胸脊神经背侧支支配的结构脱敏。需要进一步研究来评估硬膜外污染引起的并发症。
