Autonomic dysreflexia (AD) is a matter of concern in anesthetic management for patients with chronic spinal cord injury. The patient was a 56-year-old man with complete paralysis from the 11th thoracic vertebra and below. He was scheduled for an orchiectomy to treat a left scrotal abscess. He reported no history of AD in activities of daily living. Since intravesical operation was not planned for this procedure, the possibility of intraoperative AD was considered to be low. The procedure could have been performed without anesthesia, but it was performed with monitored anesthesia care (MAC) to respond rapidly in case of AD onset. The surgery proceeded with continuous administration of dexmedetomidine (DEX) and intermittent administration of fentanyl. The bispectral index value was 35-78 and Richmond Agitation-Sedation Scale score was-1 to-2. AD did not occur during the surgery, and the anesthesia was managed safely. DEX has been reported to exert an inhibitory effect on AD. Therefore, this drug may be useful as a sedative during MAC for patients with spinal cord injury.