Avaliação da técnica de bloqueio intraconal em cães guiada por ultrassonografia: abordagem “em plano” – estudo cadavérico

Resumo (EN)

Anesthetic blocks concomitant with inhalational anesthesia are currently safe protocols for pain control in veterinary medicine. The use of ultrasonography to guide the needle into retrobulbar blocks is necessary to achieve the correct site to deposition of local anesthetic and to avoid possible trauma to the ocular bulb. In this study, the needle approach was performed within the plane of the ultrasonographic plane with deposition of two volumes of dye solution. Initially an anatomical study of canine corpses was performed to understand the anatomical structures involved. Subsequently, the dye was applied with two distinct volumes (0.1 and 0.05 mL / cm of distance between the occipital bone and the frontomaxillary fissure) in the intraconal space. The results observed after resection of the ocular structures with the dye were similar in both volumes, with difference only in the way of the dispersion inside the optical cone. We concluded that, as the dye dispersion in the intraconal space was similar in both volumes, akinesia and analgesia of the optic bulb could be expected in clinical situations with lower volumes. However, reduction of volumes used in anesthetic blocks is only possible when the needle is correctly positioned and, in this case, the ultrasound allows real-time visualization of the dispersion of the anesthetic in the optical cone.