Avaliação anatômica do bloqueio do plano transverso do abdômen guiado por ultrassom, em caprinos.

Abstract

The aim of this study was to anatomically evaluate the technique of transverse abdominal plane anesthesia blockade guided by ultrasound in goats, as well as the extent reached by the infused solution. Three healthy goats of the Moxotó breed, weighing 21.0 ± 4.58 kg and aged between 1 and 4 years, were used. The animals were sedated with acepromazine 1% (0.1 mg/kg, IV) and then euthanized with xylazine 2% (1 mg/kg, IV) and anesthetic induction with propofol 1% (IV) in a dose-effect system until the second plane of the third anesthetic stage, as described by Guedel, was reached. After the disappearance of the palpebral reflex, a 10% potassium chloride solution (1 mL/kg, IV) was administered. Immediately after confirmation of death, bilateral blockade was performed at the paracostal and umbilical puncture points with a 1:1 solution containing 0.25% bupivacaine and 1% methylene blue, at a dose of 0.2 mL/kg/point. Between 15 and 45 minutes after the blockade, abdominal wall dissection was performed to observe the nerve branches and the transverse abdominal muscle. A total of six hemi-abdominal walls were visualized. The average volume injected was 4.33 ± 1.14 per point. The nerves that showed the highest frequency of staining were T12 and L1 (66.7%), T11, T13, and L2 (50.0%), and L3 (33.3%). The T10 nerve was not stained at any of the points. Animal 2 showed the best results, followed by animals 1 and 3. It is concluded that the transverse abdominal plane blockade in goats proved to be difficult to perform, especially when using two puncture points, as it resulted in inefficient dispersion of the injected dye solution, which was inadequate for ensuring good anesthesia for abdominal surgeries.