Horses underwent either cervical epidural space (CES) catheterization or subarachnoid space (SAS) catheterization while restrained in stocks, under deep sedation (detomidine and morphine) and local anesthesia (mepivacaine 2%) block. Catheters were placed under ultrasound guidance with visualization of the dura, SAS, and spinal cord between the first (C1) and second (C2) cervical vertebrae. Following sedation and sterile skin preparation, operator 1 placed under ultrasound guidance, a 6- or 8-inch Tuohy needle with the bevel oriented caudally. For CES, a 6-inch Touhy needle was used with the hanging drop technique to detect negative pressure, and operator 2 then passed the epidural catheter into the CES. For SAS, following puncture of the dura, cerebrospinal fluid (CSF) was aspirated prior to placement of the epidural catheter. Placement into either CES or SAS was confirmed with plain and contrast radiography. Catheters were wrapped for the duration of the study. CSF cytology was assessed up to every 24 h for the study period. Horses were assessed daily for signs of discomfort, neck pain, catheter insertion site swelling, or changes in behavior. A complete postmortem assessment of the spinal tissues was performed at the end of the study period (72 h). Two horses had CES catheters and five horses had SAS catheters placed successfully. All horses tolerated the catheter well for the duration of the study with no signs of discomfort. Ultrasound was essential to assist placement, and radiography confirmed the anatomical location of the catheters. CSF parameters did not change over the study period (P > 0.9). There was evidence of mild meningeal acute inflammation in one horse and hemorrhage in another consistent with mechanical trauma. Placement of an indwelling CES or SAS catheter appears to be safe, technically simple, and well tolerated in standing sedated normal horses.

中文翻译：

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站立成年马的颈硬膜外和蛛网膜下腔导管放置。

对马进行颈部硬膜外腔（CES）导管插入术或蛛网膜下腔（SAS）导管插入术，同时在深度镇静（去毒定和吗啡）和局部麻醉（甲哌卡因2％）阻滞下对马进行约束。将导管置于超声引导下，可视化第一颈椎（C1）和第二颈椎（C2）之间的硬脑膜，SAS和脊髓。在进行镇静和无菌皮肤准备后，操作员1置于超声引导下，将6英寸或8英寸的Tuohy针头朝尾倾斜。对于CES，使用6英寸的Touhy针和悬挂滴技术检测负压，然后操作员2将硬膜外导管送入CES。对于SAS，在穿刺硬脑膜后，在放置硬膜外导管之前先抽吸脑脊液（CSF）。通过普通X射线和对比X射线照相术可以确定是否将其放置在CES或SAS中。在研究期间将导管包裹起来。在研究期间，每24小时评估CSF细胞学检查一次。每天评估马的不适，颈部疼痛，导管插入部位肿胀或行为改变的迹象。在研究期（72小时）结束时，对脊髓组织进行了完整的验尸评估。成功安装了两匹马的CES导管和五匹马的SAS导管。在研究期间，所有马匹都很好地耐受了导管，没有不适的迹象。超声对于辅助放置至关重要，并且放射线照相术可以确认导管的解剖位置。在研究期间，脑脊液参数没有变化（P> 0.9）。有证据表明，一匹马患有轻度脑膜急性炎症，另一匹马出血与机械性创伤一致。在站立的镇静正常马匹中，放置CES或SAS导尿管似乎是安全，技术简单且耐受性良好的。