Bell Marshall T, Reece T Brett, Smith Phillip D, Mares Joshua, Weyant Michael J, Cleveland Joseph C, Freeman Kirsten A, Fullerton David A, Puskas Ferenc
Department of Surgery, Division of Cardiothoracic Surgery, University of Colorado;
Department of Surgery, Division of Cardiothoracic Surgery, University of Colorado.
J Vis Exp. 2014 Mar 3(85):50910. doi: 10.3791/50910.
Lower extremity paralysis continues to complicate aortic interventions. The lack of understanding of the underlying pathology has hindered advancements to decrease the occurrence this injury. The current model demonstrates reproducible lower extremity paralysis following thoracic aortic occlusion.
Adult male C57BL6 mice were anesthetized with isoflurane. Through a cervicosternal incision the aorta was exposed. The descending thoracic aorta and left subclavian arteries were identified without entrance into pleural space. Skeletonization of these arteries was followed by immediate closure (Sham) or occlusion for 4 min (moderate ischemia) or 8 min (prolonged ischemia). The sternotomy and skin were closed and the mouse was transferred to warming bed for recovery. Following recovery, functional analysis was obtained at 12 hr intervals until 48 hr.
Mice that underwent sham surgery showed no observable hind limb deficit. Mice subjected to moderate ischemia for 4 min had minimal functional deficit at 12 hr followed by progression to complete paralysis at 48 hr. Mice subjected to prolonged ischemia had an immediate paralysis with no observable hind-limb movement at any point in the postoperative period. There was no observed intraoperative or post operative mortality.
Reproducible lower extremity paralysis whether immediate or delayed can be achieved in a murine model. Additionally, by using a median sternotomy and careful dissection, high survival rates, and reproducibility can be achieved.
下肢麻痹仍是主动脉介入治疗的并发症。对潜在病理机制的认识不足阻碍了降低这种损伤发生率的进展。当前模型显示在胸主动脉闭塞后可重现下肢麻痹。
成年雄性C57BL6小鼠用异氟醚麻醉。通过颈胸切口暴露主动脉。识别胸降主动脉和左锁骨下动脉，不进入胸膜腔。这些动脉骨骼化后立即缝合（假手术）或闭塞4分钟（中度缺血）或8分钟（长时间缺血）。关闭胸骨切开术和皮肤，将小鼠转移到保温床上恢复。恢复后，每隔12小时进行功能分析，直至48小时。
接受假手术的小鼠未出现明显的后肢缺陷。经历4分钟中度缺血的小鼠在12小时时功能缺陷最小，随后在48小时时进展为完全麻痹。经历长时间缺血的小鼠术后立即出现麻痹，术后任何时间均未观察到后肢运动。未观察到术中或术后死亡。
在小鼠模型中可重现即时或延迟的下肢麻痹。此外，通过使用正中胸骨切开术和仔细解剖，可实现高生存率和可重复性。
