Microvascular coaptation methods: device manufacture and computational simulation

The practice of joining blood vessels has been ongoing since the late nineteenth century, although it was initially restricted to animal studies and experimental techniques. At this time, fine silk thread and curved needles had been introduced (1), which was a significant advancement on previous suture materials such as leather, tendon and catgut (2) – although these were used for wound closure rather than vascular repair. It was not until the mid twentieth century, circa World War II, that vascular anastomoses were performed whilst repairing or reconstructing traumatic injuries (3). The natural progression from repairing vascular injuries was to perform these procedures in smaller and smaller vessels. Of course, this necessitated use of an operating microscope and development and manufacture of finer suture materials, needles, and more delicate instruments. This chapter aims to provide details of the common microvascular anastomotic devices and their manufacture

Microvascular Anastomotic Coupler Assessment in Head and Neck Reconstruction

OBJECTIVE. To assess the advantages of using mechanical anastomotic systems in head and neck free tissue transfer. STUDY DESIGN. Case series with chart review. SETTING. A university-based tertiary care center. SUBJECTS AND METHODS. A retrospective review of mechanical venous coupler devices in head and neck reconstruction performed between October 2004 and December 2006. A total of 261 venous anastomoses were performed in 234 consecutive patients. Five types of flaps were performed: radial forearm (66%), anterior lateral thigh (12%), fibula (9%), rectus abdominis (8%), and latissimus dorsi (2%). Demographic data were collected, and the outcomes measured were flap survival and microvascular complications. RESULTS. The size of the venous anastomosis ranged from 1.5 to 4.0 mm, with most being 3.0 mm (56%) followed by 3.5 mm (23%). The most common recipient vein used was an unidentified venous branch off the internal jugular vein (76%) followed by the external jugular vein (17%). Microvascular complications occurred in <5% (n = 11) of patients, with >50% of those being arterial insufficiency (n = 7). Total failures occurred in 3% (n = 7) of patients: 1.5% (n = 4) acute failures (<5 days) and 1.5% (n = 3) late failures. Of the acute failures, causes included venous congestion (n = 1) and arterial insufficiencies (n = 3). The venous coupler used in the failures was 3.0 mm in diameter. Free flap failures resulting from arterial insufficiency involved coupling to the external jugular vein, while the remaining free flap failures (n = 4) used the internal jugular vein. CONCLUSION. With an early venous failure rate of 0.38%, mechanical anastomosis is an adequate alternative to hand-sewn techniques