Anaesthetic implications of free-flap microvascular surgery for head and neck malignancies - A relook.

Head and neck free-flap microvascular surgery is a type of surgery where multiple anaesthetic factors play a very important role in the outcome of the surgery while the conduct of anaesthesia itself may be quite challenging for the anaesthesiologist. In microvascular reconstruction of head and neck malignancies, flaps are used to reconstruct a primary defect formed by wide local excision. A free flap is raised after removing the neurovascular pedicle from the donor site and transplanting it by microvascular anastomosis to the new location. This gives rise to a secondary defect which is then repaired by direct suture or skin graft. The anaesthesiologist's role includes optimizing the physiological conditions for the survival of the flap while decreasing morbidity at the same time. Failure of the free flap is attributed to numerous causes. This is an attempt to highlight them along with discussion of the anaesthesia-related issues that are faced during this type of surgery. The various pre-, intra- and postoperative factors affecting flap survival and overall postoperative outcome in the patient are discussed here.