Shaughness Gabrielle, Blackburn Collin, Ballestín Alberto, Akelina Yelena, Ascherman Jeffrey A
New York, N.Y.; and Cáceres, Spain.
From Columbia University Medical Center; and the Department of Microsurgery, Jesús Usón Minimally Invasive Surgery Center.
Plast Reconstr Surg. 2017 Jun;139(6):1400-1405. doi: 10.1097/PRS.0000000000003350.
Thrombosis is a common source of failure in anastomoses, flaps, and vascular grafts. Ensuring vessel patency is critical to the success of microvascular procedures. Any tool that can accurately predict the patency of an anastomosis intraoperatively would enable the surgeon to detect and correct flow restrictions while the patient is still in the operating room.
The authors used transit-time ultrasound technology in this pilot study to investigate whether a minimal cutoff value for quantitative postoperative blood flow (in milliliters per minute) could be established that would reliably predict sustained vessel patency at 24 hours postoperatively. Surgical end-to-end anastomoses were performed on 56 Sprague-Dawley rat femoral arteries with diameters ranging from 0.6 to 1.2 mm. Postoperative blood volume flow measurements were taken at 20-minute intervals up to 1 hour, and then again at 24 hours, to assess patency.
Forty-seven anastomoses (83.9 percent ) were patent 24 hours after surgery. Nine anastomoses (16.1 percent ) thrombosed within 24 hours. Based on a receiver operating characteristic curve analysis, the optimal cutoff value for immediate postoperative flow for predicting thrombosis within 24 hours of microvascular anastomosis is 0.21 ml/minute.
At 20 minutes postoperatively, blood flows greater than 0.30 ml/minute are highly suggestive of patency, and flows less than 0.21 ml/minute are highly suggestive of failure. The authors therefore recommend a minimal cutoff flow value of 0.30 ml/minute for vessels ranging from 0.6 to 1.2 mm in diameter to predict long-term postoperative vascular patency.
血栓形成是吻合口、皮瓣和血管移植物失败的常见原因。确保血管通畅对微血管手术的成功至关重要。任何能够在术中准确预测吻合口通畅性的工具，都能使外科医生在患者仍在手术室时检测并纠正血流受限情况。
在这项初步研究中，作者使用渡越时间超声技术来研究是否可以确定一个术后定量血流（每分钟毫升数）的最小临界值，该临界值能够可靠地预测术后24小时血管的持续通畅情况。对56只直径在0.6至1.2毫米之间的斯普拉格-道利大鼠股动脉进行了手术端端吻合。术后每隔20分钟测量一次血容量流量，直至1小时，然后在24小时时再次测量，以评估通畅情况。
47个吻合口（83.9%）在术后24小时通畅。9个吻合口（16.1%）在24小时内发生血栓形成。基于受试者工作特征曲线分析，微血管吻合术后24小时内预测血栓形成的术后即时血流最佳临界值为0.21毫升/分钟。
术后20分钟时，血流大于0.30毫升/分钟高度提示通畅，而血流小于0.21毫升/分钟高度提示失败。因此，作者建议对于直径在0.6至1.2毫米之间的血管，采用0.30毫升/分钟的最小临界血流值来预测术后长期血管通畅情况。
