Microvascular surgery refers to the surgical coaptation of small vessels usually less than 3 mm in diameter.
This technique has evolved significantly over the last four decades, starting from replantations and revascularizations to free-flap surgery.
The operating microscope and the development of loupes, microinstruments, and microsutures have greatly aided its widespread use.
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.
The disadvantages of microsurgery include the steep learning curve, lengthy operative times, and the need for technical expertise and specially trained personnel.
In free-flap surgery, indications, contraindications, and timing are critical. Good preoperative planning is required, including the selection of the appropriate flap and recipient vessels.
Experience is vital in postoperative monitoring of free flaps; early detection of a failing free flap with prompt intervention greatly improves the salvage rates.
The majority of complications are related to vascular compromise and many relate to pedicle thrombosis due to kinking, compression, or technical error.
Early detection and prompt surgical exploration are mandatory if vascular compromise is suspected. Pharmacological agents such as aspirin, heparin, and dextran are also useful adjuncts.
Despite the improvements in techniques and postoperative care, flap failure rates remain around 3%. Managing these cases can be one of the most challenging aspects of reconstructive microsurgery.
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.
