Objective

To evaluate staining of nerve branches after the injection of different volumes during ultrasound-guided transversus abdominis plane (TAP) block in dog cadavers.

Study design

Prospective randomized study.

Animals

A total of 15 frozen/thawed adult dog cadavers.

Methods

Hemiabdomens were randomly allocated to one of four groups. In groups G0.3, G0.6 and G1.0, ropivacaine–methylene blue solution (0.3, 0.6 and 1.0 mL kg^–1 in seven, eight and eight hemiabdomens, respectively) was injected at the midpoint between the iliac crest and the last rib at the height of the shoulder. In group G0.3×2 (seven hemiabdomens), two injections (0.3 mL kg^–1) were performed, caudal to the last rib and cranial to the iliac crest at the same height. Total time for injection was recorded; after 30 minutes, cadavers were dissected and spread of dye was evaluated.

Results

Accuracy of injection site was 80% and injection time was 71 (48–120) seconds for all groups together. Craniocaudal spread was 6.4 ± 1.6, 9.1 ± 2.6, 11.4 ± 2.3 and 11.2 ± 3.8 cm for G0.3, G0.6, G1.0 and G0.3×2, respectively [G0.3 to G0.3×2 (p = 0.044) and G1.0 (p = 0.034)]. There was no difference in dorsoventral spread among groups. Number of ventral nerve branches stained was 3 (2–4), 3 (2–4), 3 (3–4) and 3 (2–4) for G0.3, G0.6, G1.0 and G0.3×2, respectively, including nerve branches from twelfth thoracic to third lumbar (L3) in different proportions among groups.

Conclusions and clinical relevance

Results suggest that a single-injection TAP block, using 0.3 mL kg^–1, stains comparable number of nerve branches as higher volumes or two-point injection. Despite the volume or technique, consistent staining of the innervation of the caudal abdomen (L1–L3) was observed. Additional cadaveric studies are necessary to identify the optimal technique for complete abdominal wall staining.

中文翻译：

---

犬尸体腹横肌平面阻滞注射量的评估：初步试验

客观的

评估在超声引导下腹横肌平面 (TAP) 阻滞狗尸体期间注射不同体积后神经分支的染色。

学习规划

前瞻性随机研究。

动物

总共 15 具冷冻/解冻的成年犬尸体。

方法

偏腹被随机分配到四组之一。在 G0.3、G0.6 和 G1.0 组中，罗哌卡因-亚甲蓝溶液（分别为 0.3、0.6和 1.0 mL kg ^-1，分别在 7、8 和 8 个半腹中）注射在髂嵴和腹股沟之间的中点。肩部高度的最后一根肋骨。在 G0.3×2 组（7 个半腹）中，进行了 2 次注射（0.3 mL kg ^–1），在相同高度的最后一根肋骨的尾部和髂嵴的颅骨。记录注射的总时间；30 分钟后，解剖尸体并评估染料的扩散。

结果

所有组的注射部位准确度为 80%，注射时间为 71 (48-120) 秒。G0.3、G0.6、G1.0和G0.3×2的颅尾扩散分别为6.4±1.6、9.1±2.6、11.4±2.3和11.2±3.8厘米[G0.3至G0.3×2（p  = 0.044) 和 G1.0 ( p  = 0.034)]。各组之间的背腹扩散没有差异。对于 G0.3、G0.6、G1.0 和 G0.3，染色的腹神经分支数为 3 (2-4)、3 (2-4)、3 (3-4) 和 3 (2-4) 个×2，分别包括各组不同比例的第十二胸椎至第三腰椎（L3）神经分支。

结论和临床相关性

结果表明，使用 0.3 mL kg ^–1的单次注射 TAP 阻滞剂染色的神经分支数量与较大体积或两点注射相当。尽管体积或技术，尾腹部（L1-L3）的神经支配的一致染色被观察到。需要额外的尸体研究来确定完整腹壁染色的最佳技术。