26 Principles and techniques of microvascular surgery
Various techniques have been developed for the handling of small vessels. There are several ways in which the anastomosis can be performed after careful vessel preparation. The most commonly used techniques are the end-to-end, end-to-side and the use of the anastomotic coupling devices.
Difficult situations such as vessel diameter discrepancy and poor vessel quality with atherosclerotic plaques and loose intima can usually be overcome with special techniques. Inadequate vessel length can be managed with microvascular grafts.
While previously considered only when simpler methods of reconstruction were unfeasible, free tissue transfers have become commonplace and are now first-line options for single-stage reconstruction, with superior functional and aesthetic outcomes.
Microsurgery has indeed revolutionized our approach to reconstructive challenges. With further refinements, we will see an even wider application, particularly in the fields of supramicrosurgery, freestyle free flaps, composite tissue allotransplantation, and tissue engineering.
Microsurgery refers to surgery that takes place under microscope magnification. Within the field of plastic surgery, it encompasses microvascular, microneural, microlymphatic, and microtubular surgery. Specifically, microvascular surgery refers to the surgical coaptation of small vessels performed under magnification and illumination. In a clinical setting, it is often used synonymously with the term “reconstructive microsurgery,” and is implied in replantations and free tissue transplantations.
The introduction of the operating microscope in 1960 heralded the beginnings of the era of microsurgical reconstruction and it is generally used with vessels which are 3 mm or less in diameter in conjunction with specially designed fine instrumentation and microsutures. As an alternative, surgical loupes with magnifications of 2.5×–8× can be used.
Over the last four decades, microvascular surgery has become an indispensable tool for the reconstruction of complex defects. While previously considered only when simpler methods of reconstruction were unfeasible, free tissue transfers have become commonplace and are now being considered as a first-line option to provide superior outcomes, both functionally and aesthetically. Other benefits include time effectiveness and better economy in breast, head and neck, and extremities reconstruction, with even psychological advantages.
There are, of course, also disadvantages of microsurgery, including the steep learning curve, lengthy operative times, need for special resources, technical expertise, and considerable investment in instruments and specially trained personnel. Despite improvements in techniques and postoperative care, there is a small but not insignificant risk of flap failures of 2–3% even in the best surgical units.
This chapter details the tools and techniques used to maximize microvascular surgical outcome. Also discussed are the principles of microvascular surgery particularly with respect to free-flap surgery, options available when failure occurs, and the future of microvascular surgery. Replantations are highlighted in a separate chapter.