These occur when the blood supply is inadequate for the volume of tissue transferred. In most cases only limited surgery is required for correction of these complications. In this outpatient operation the tissue to be transferred is incised along the boundary of the proposed transfer but is not elevated. This results in a change in the blood supply which renders the flap more robust and less susceptible to ischemic complications. Delay procedures are performed 7 to 14 days in advance of the reconstructive surgery.
Free flaps tend to be more robust than their pedicled counterparts.
The number of complications is lower than with pedicled transfers but the complications that occur can be more severe. When the blood vessels are cut and reattached using microsurgical technique there is the possibility of blood flow problems at the sites of vessel anastamoses, either arterial or venous. These problems can result in death of the entire flap if not noted and repaired in timely fashion. For this reason patients who undergo free tissue transfer are required to stay in the hospital a bit longer than those who have a pedicle tissue transfer. Free flaps are monitored closely by nursing, typically in an Intensive Care Unit, for 3 to 5 days to make sure that everything progresses as intended.