Experimental study on the closure of large defects of the oral cavity using a free island flap with microvascular anastomosis.

The present study demonstrates that a free island flap with microvascular anastomosis may be used for the closure of a large defect in the oral cavity of the pig. In control cases, when a similar flap was transferred without microvascular anastomosis, a total and rapid slough occurred. Technical details are important in this kind of surgery. The island flap should be sized appropriately, cautiously defatted, and sutured into the defect before doing the microvascular anastomosis. Tension, torsion, or kinking of the vessels to be anastomosed must be meticulously avoided. In suturing these small vessels, microvascular techniques must be strictly adhered to. No anticoagulation is needed. The free island flap does not need to be perfused. Close observation of the flap's capillary refill, tissue turgor, and color is essential in the early postoperative period. More recently, Doppler technique has enabled us to monitor blood flow in the flap more accurately. If initial signs of venous congestion or arterial insufficiency are noted, examination of the anastomotic site can and should be done. Revision, if indicated, may result in rescue of the flap (as it was described in pig No. 8). The results of this experimental study allowed us recently to use this method successfully in two patients. Both had oral cavity carcinomas. In the first, the flap measured 5x7x2 cm and in the second 9x10x1.5 cm. They are now nine weeks and five weeks respectively, without any signs of failure. The details will be given when we have a series of patients adequate for a definitive report.