Rare cases requiring emergency procedures while harvesting a free forearm flap: report of two cases.

The free forearm flap is considered safe to harvest and is still extremely useful for reconstruction after head and neck tumor resection. We experienced two uncommon cases, in which an emergency procedure was required during reconstructive surgery after resection of head and neck cancer. Case 1 suffered persistent hand blood flow insufficiency long after the flap was placed in the oral cavity. Case 2 had an anomalous cutaneous vein of the forearm that was a drainage vein of the flap. For risk management during free flap surgery, preparing multiple venous transplant options in advance is fundamental.