Víctor López-Ramis , Michela Re , Susana Canfrán , Mario Arenillas , Ignacio De Gaspar , Ignacio A. Gómez de Segura , Javier Blanco Murcia
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引用次数: 0
Abstract
Objective
To describe an ultrasound-guided technique for anaesthesia of the pudendal nerve with evaluation of the anatomical spread of a bupivacaine-methylene blue solution in sheep.
Study design
Prospective, experimental study.
Animals
A total of seven adult experimental sheep and one sheep cadaver.
Methods
The study had two phases. First, the anatomy and ultrasound imaging of the gluteal region, caudal to the region of tuber coxae was reviewed in one sheep cadaver. Second, in seven healthy sedated sheep, a linear transducer (8–13 MHz) was positioned on the lateral area of the hip to identify pudendal vessels at the level of the ischial spine ventral to the sacrotuberous ligament. The right and left pudendal nerves area were injected with 0.1 mL kg-1 of a 1:1 solution of bupivacaine-methylene blue. The ultrasound image quality was considered as excellent, good, or poor. Following euthanasia, both pudendal areas were dissected and the staining of the nerves assessed, expressed as the percentage of success (%) and compared with the chi-square test.
Results
The relevant ultrasound landmarks were visualized in both areas of all sheep, with an excellent visualization of the landmarks before and during injection in most cases (13/14). On dissection, methylene blue dispersion was observed surrounding the pudendal nerve, with at least 1 cm length in 13/14 cases (93%; the remainder partially stained). No evidence of dye was found around the sciatic nerve in any case nor was there any evidence of haematoma or faecal contamination within the punctured area.
Conclusions and clinical relevance
Ultrasound-guided injection with 0.1 mL kg-1 in close proximity to the pudendal nerve at the ischial spine level resulted in a high success rate of nerve staining. This procedure may be a suitable technique for pudendal nerve blockade providing analgesia for common reproductive or perineal surgical procedures in sheep.
目的:介绍一种超声引导下的阴部神经麻醉技术,并评价布比卡因-亚甲蓝溶液在绵羊体内的解剖分布。研究设计:前瞻性实验研究。实验动物:7只成年实验羊和1只羊尸体。方法:研究分为两个阶段。首先,回顾了一具羊尸体的臀区、尾侧至髋部的解剖和超声成像。其次,在7只健康的镇静绵羊中,在髋关节外侧区域放置一个线性传感器(8-13 MHz),以识别骶结节韧带腹侧坐骨棘水平处的阴部血管。在左右阴部神经区注射0.1 mL kg-1的1:1的布比卡因-亚甲基蓝溶液。超声图像质量分为优、良、差三个等级。安乐死后,解剖两个阴部区域并评估神经染色,以成功率(%)表示,并与卡方检验进行比较。结果:所有羊的两个区域均可见相关超声标志,大多数病例在注射前和注射过程中具有良好的标志显示(13/14)。解剖时,阴部神经周围可见亚甲基蓝弥散,13/14例(93%;其余部分染色)。在任何情况下,坐骨神经周围都没有发现染料的证据,也没有在穿刺区域发现血肿或粪便污染的证据。结论及临床意义:超声引导下在坐骨棘水平近阴部神经处注射0.1 mL kg-1,神经染色成功率高。这种方法可能是一种适用于阴部神经阻滞的技术,为绵羊常见的生殖或会阴外科手术提供镇痛。
期刊介绍:
Veterinary Anaesthesia and Analgesia is the official journal of the Association of Veterinary Anaesthetists, the American College of Veterinary Anesthesia and Analgesia and the European College of Veterinary Anaesthesia and Analgesia. Its purpose is the publication of original, peer reviewed articles covering all branches of anaesthesia and the relief of pain in animals. Articles concerned with the following subjects related to anaesthesia and analgesia are also welcome:
the basic sciences;
pathophysiology of disease as it relates to anaesthetic management
equipment
intensive care
chemical restraint of animals including laboratory animals, wildlife and exotic animals
welfare issues associated with pain and distress
education in veterinary anaesthesia and analgesia.
Review articles, special articles, and historical notes will also be published, along with editorials, case reports in the form of letters to the editor, and book reviews. There is also an active correspondence section.