The goal of this clinical trial is to evaluate whether goal-directed fluid therapy (GDFT) can improve the postoperative recovery in patients undergoing head and neck cancer surgery. It aims to answer is: • Whether GDFT can reduce the occurrence of serious postoperative complications? Researchers will compare GDFT protocol to a standard conventional fluid therapy in head and neck cancer surgery to see if GDFT strategy works to improve the postoperative recovery. Participants will - Receive GDFT protocol or a conventional fluid therapy during the surgery. - Be continuously follow-up during hospitalization and after discharge to record the occurrence of postoperative complications.