Miller Anna N, Deal Dwight, Green James, Houle Timothy, Brown William, Thore Clara, Stump David, Webb Lawrence X
Departments of Orthopaedic Surgery (A.N.M.), Cardiothoracic Surgery (D.D., T.H., and D.S.), Anesthesiology (D.S.), and Radiology (W.B. and C.T.), Wake Forest School of Medicine, Winston-Salem, North Carolina
Departments of Orthopaedic Surgery (A.N.M.), Cardiothoracic Surgery (D.D., T.H., and D.S.), Anesthesiology (D.S.), and Radiology (W.B. and C.T.), Wake Forest School of Medicine, Winston-Salem, North Carolina.
J Bone Joint Surg Am. 2016 Apr 20;98(8):658-64. doi: 10.2106/JBJS.14.01176.
Approximately 2 million patients in the United States annually undergo total joint arthroplasty with reaming and placement of intramedullary nails, resulting in extravasation of bone marrow and fat into the circulatory system and potentially causing fat embolism syndrome. Acute and chronic changes in mental status documented after these procedures may be related to embolic events. The Reamer/Irrigator/Aspirator (RIA) device has been shown to decrease intramedullary pressure during reaming. We hypothesized that the use of the RIA in a canine model would reduce the number of microemboli detected in the carotid artery and brain compared with nailing either with or without reaming.
Twenty-four large canines underwent unreamed nailing (UR), sequentially reamed nailing (SR), or RIA-reamed nailing (RIA) of bilateral femora (eight dogs per group). During reaming and nailing, the number and size of microemboli transiting the carotid artery were recorded. After euthanasia, the brain was harvested for immunostaining and measurement of microinfarction volumes.
Total embolic load passing through the carotid artery was 0.049 cc (UR), 0.045 cc (SR), and 0.013 cc (RIA). The number and size of microemboli in the UR and SR groups were similar; however, the RIA group had significantly fewer larger-sized (>200-μm) emboli (p = 0.03). Pathologic examination of the brain confirmed particulate emboli, and histologic analyses demonstrated upregulation of stress-related proteins in all groups, with fewer emboli and less evidence of stress for RIA reaming.
RIA reaming decreased microemboli compared with traditional reaming and unreamed nailing, suggesting that intramedullary pressure and heat are important variables. The documented embolic events and brain stress may help to explain subtle neurobehavioral symptoms commonly seen in patients after undergoing long-bone reaming procedures.
RIA reaming decreased cranial embolic events and may have an ameliorating effect on postoperative neurologic sequelae.
在美国，每年约有200万患者接受全关节置换术，术中需扩髓并置入髓内钉，这会导致骨髓和脂肪外渗至循环系统，进而可能引发脂肪栓塞综合征。这些手术后记录的急性和慢性精神状态变化可能与栓塞事件有关。扩髓冲洗吸引器（RIA）已被证明可在扩髓过程中降低髓内压力。我们推测，与单纯钉入或扩髓后钉入相比，在犬类模型中使用RIA会减少在颈动脉和大脑中检测到的微栓子数量。
24只大型犬双侧股骨分别接受非扩髓钉入（UR）、顺序扩髓钉入（SR）或RIA扩髓钉入（RIA）（每组8只犬）。在扩髓和钉入过程中，记录通过颈动脉的微栓子数量和大小。安乐死后，取出大脑进行免疫染色并测量微梗死体积。
通过颈动脉的总栓塞负荷在UR组为0.049立方厘米，SR组为0.045立方厘米，RIA组为0.013立方厘米。UR组和SR组的微栓子数量和大小相似；然而，RIA组较大尺寸（>200μm）的栓子明显更少（p = 0.03）。大脑的病理检查证实存在颗粒性栓子，组织学分析表明所有组中应激相关蛋白均上调，RIA扩髓组的栓子更少且应激证据更少。
与传统扩髓和非扩髓钉入相比，RIA扩髓减少了微栓子，表明髓内压力和热量是重要变量。记录的栓塞事件和脑应激可能有助于解释长骨扩髓手术后患者常见的细微神经行为症状。
RIA扩髓减少了颅内栓塞事件，可能对术后神经后遗症有改善作用。
