Najman Ilana E, Ferreira Joana Z, Abimussi Caio J X, Floriano Beatriz P, Meneghetti Thais M, Oliva Valéria N L S, do Nascimento Paulo
Department of Anesthesiology, Botucatu School of Medicine, UNESP - Universidade Estadual Paulista, Botucatu, SP, Brazil.
Department of Animal Science, Araçatuba Veterinary School, UNESP - Universidade Estadual Paulista, Araçatuba, SP, Brazil.
Vet Anaesth Analg. 2015 Jul;42(4):433-41. doi: 10.1111/vaa.12237. Epub 2014 Dec 1.
This study aimed to evaluate the benefit and specifically the feasibility of using ultrasound in ophthalmologic periconal block, and the occurrence of complications.
Prospective experimental study.
Ten healthy New Zealand White rabbits (6-8 months of age), weighing 2.0-3.5 kg.
Rabbits were anesthetized by intramuscular injection of acepromazine (1 mg kg(-1)), ketamine (30 mg kg(-1)) and xylazine (3 mg kg(-1)). Ultrasound-assisted periconal block with lidocaine was performed on 18 eyes. Intraocular pressure was measured by applanation tonometry whereas corneal sensitivity was assessed using an esthesiometer, before and after each periconal anesthesia.
In all 18 eyes, it was possible to adequately visualize the needle shaft within the periconal space, as well as muscular cone, optic nerve and local anesthetic solution spread. Lidocaine 2% without epinephrine (0.79 ± 0.19 mL) was injected into the periconal space. There was no statistical difference between the intraocular pressure (mean ± SD) measured before (10.9 ± 2.9 mmHg) and after (11.9 ± 3.8 mmHg) the periconal anesthesia (p = 0.38). The effectiveness of the ultrasound-assisted technique was shown according to the values for corneal sensitivity, assessed before and after periconal anesthesia (p < 0.0001). Complications were not observed in this study.
Eye ultrasonography allowed visualization of all anatomic structures necessary to perform a periconal block, as well as the needle insertion and anesthetic spread in real time. Further studies are required to prove the real potential of ultrasound for reducing the incidence of complications associated with ophthalmic blocks, especially when anatomic disorders of the eye could potentially increase the risk.
Ultrasonography is a painless, noninvasive tool that may improve safety of ophthalmic regional blocks, potentially by reducing the prevalence of globe perforation or penetration of the optic nerve associated with the needle-based techniques.
本研究旨在评估超声在眼科眶周阻滞中的益处，特别是其可行性以及并发症的发生情况。
前瞻性实验研究。
10只健康的新西兰白兔（6 - 8月龄），体重2.0 - 3.5千克。
通过肌肉注射乙酰丙嗪（1毫克/千克）、氯胺酮（30毫克/千克）和赛拉嗪（3毫克/千克）对兔子进行麻醉。对18只眼睛进行超声引导下的眶周利多卡因阻滞。在每次眶周麻醉前后，使用压平眼压计测量眼压，并用感觉计评估角膜敏感性。
在所有18只眼睛中，均能清晰观察到眶周间隙内的针杆以及肌锥、视神经和局部麻醉药的扩散情况。将不含肾上腺素的2%利多卡因（0.79±0.19毫升）注入眶周间隙。眶周麻醉前后测量的眼压（平均值±标准差）之间无统计学差异（麻醉前为10.9±2.9毫米汞柱，麻醉后为11.9±3.8毫米汞柱，p = 0.38）。根据眶周麻醉前后评估的角膜敏感性值显示了超声辅助技术的有效性（p < 0.0001）。本研究未观察到并发症。
眼部超声检查能够实时显示进行眶周阻滞所需的所有解剖结构，以及针的插入和麻醉药的扩散情况。需要进一步研究以证明超声在降低与眼科阻滞相关并发症发生率方面的实际潜力，特别是当眼部解剖结构紊乱可能增加风险时。
超声检查是一种无痛、非侵入性工具，可能通过降低与基于针的技术相关的眼球穿孔或视神经穿透的发生率来提高眼科区域阻滞的安全性。
