Ultrasound-guided ischiorectal fossa block targeting the pudendal nerve in dogs: a cadaveric study

IF 1.9 2区农林科学 Q2 VETERINARY SCIENCES

Veterinary anaesthesia and analgesia Pub Date : 2025-03-24 DOI:10.1016/j.vaa.2025.03.012

Jalise N. Zumstein, Erin K. Keenihan, Jessica D. Briley

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引用次数: 0

Abstract

Objective

To describe an ultrasound-guided (USG) regional anesthesia technique for perineural injection of the pudendal nerve (PdN) in dogs.

Study design

Prospective, randomized, anatomic study.

Animals

A total of seven thawed and 15 fresh canine cadavers.

Methods

Anatomical dissection, sonography and computed tomography (CT) techniques were used. In this study, 17 cadavers (11 males and six females), with body mass of 25.2 ± 6.3 kg (mean ± standard deviation) were used: four for anatomical study and approach development and 13 administered bilateral USG transgluteal injections. Using a dorsomedial-to-ventrolateral needle trajectory, the ischiorectal fossa was targeted medial to the ischiatic spine. Each hemipelvis was randomized to be administered high (HV, 0.2 mL kg^–1) or low (LV, 0.1 mL kg^–1) volume injections of ropivacaine–dye solution. Following injection, cadavers were dissected. Successful PdN staining (>1 cm nerve length stained) and inadvertent staining of the sciatic nerve, or rectal, urethral or intravascular puncture was recorded. Volumes were compared using a mixed effects ordinal logistic regression model (p < 0.05 considered significant).

Results

We excluded five cadavers owing to poor tissue preservation. The neurovascular bundle containing PdN and landmarks for ischiorectal fossa were defined using CT. Sonographically, landmarks were identified and dye solution injected into the fossa. Complete staining of the PdN was achieved in 69.2% (HV) and 58.3% (LV) of injections. There was no significant difference in nerve staining between groups (p = 0.864). There was no significant difference in sciatic nerve staining between HV (7.7%) and LV (8.3%) (p = 0.71). Rectal, urethral or intravascular puncture was not observed.

Conclusions and clinical relevance

This is the first description of an USG ischiorectal fossa block using a transgluteal approach targeting the PdN in dogs. The described USG technique could provide anesthesia of the urethra and perineal region. Further studies are necessary to investigate this approach in live animals.

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超声引导坐骨直肠窝阻滞瞄准犬阴部神经：一项尸体研究。

目的：介绍超声引导（USG）区域麻醉在犬阴部神经周围注射（PdN）中的应用。研究设计：前瞻性、随机、解剖研究。动物：总共有7具解冻的狗尸体和15具新鲜的狗尸体。方法：采用解剖解剖、超声和计算机断层扫描（CT）技术。在这项研究中，17具尸体（男性11具，女性6具），体重25.2±6.3 kg（平均±标准差），其中4具用于解剖研究和入路开发，13具用于双侧臀肌注射USG。使用背内侧到腹外侧的针刺轨迹，坐骨直肠窝被定位在坐骨脊柱内侧。每个半骨盆随机分为高剂量（HV, 0.2 mL kg-1）或低剂量（LV, 0.1 mL kg-1）注射罗哌卡因染料溶液。注射后，解剖尸体。记录成功的PdN染色（bbb101cm神经长度染色）和坐骨神经、直肠、尿道或血管内穿刺的意外染色。体积比较采用混合效应有序逻辑回归模型（p < 0.05认为显著）。结果：由于组织保存不良，我们排除了5具尸体。CT明确坐骨直肠窝神经血管束PdN及标志。超声检查，识别标志，并将染料溶液注入窝。在69.2% （HV）和58.3% （LV）的注射中，PdN完全染色。两组间神经染色差异无统计学意义（p = 0.864）。HV组（7.7%）与LV组（8.3%）坐骨神经染色差异无统计学意义（p = 0.71）。直肠、尿道或血管内穿刺未见。结论和临床意义：这是首次报道犬经臀肌入路靶向PdN的USG坐骨直肠窝阻滞。所描述的USG技术可以提供尿道和会阴区的麻醉。在活体动物中进一步研究这种方法是必要的。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Veterinary anaesthesia and analgesia 农林科学-兽医学

CiteScore

3.10

自引率

17.60%

发文量

审稿时长

97 days

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.