Patients, diagnosed as oromaxillofacial tumor and undergoing elective free fibular or anterolateral thigh flap reconstruction, were divided into two groups in a randomized, double-blind fashion. In Group Ropivacaine (Group R), nerve blocks were administered with 0.3% ropivacaine. In Group Ropivacaine + Dexmedetomidine (Group RD), nerve blocks were administered with 0.3% ropivacaine and 50 μg dexmedetomidine.The primary endpoints were the onset time and duration of sensory blocks. The secondary endpoints were heart rate, blood pressure, SpO2, sedation level, the duration of motor blocks.