悪性褐色細胞腫をもつ患者に対する口腔外科手術の全身管理経験

Pheochromocytoma is a tumor originating in the adrenal medulla that is known to cause unpredictable severe hypertension. In patients with malignant pheochromocytoma, the removal of the tumor is not indicated and only pharmacologic therapy is conducted, since the effective control of hypertension is unlikely. Here, we report the management of a patient with a malignant pheochromocytoma who underwent oral surgery. The patient was 44 years old and had an apical periodontal cyst. The removal of the cyst was scheduled, and the patient was treated with a high dose of doxazosin for 1 week prior to the operation to promote the adequate control of the patient’s blood pressure during surgery. We planned to monitor the blood pressure and pulse during the operation and to administer as small a dose of adrenaline-containing local anesthetic products as possible. For the initial local anesthesia, 3% mepivacaine solution without adrenaline was submucosally injected at a dose of 5.1 ml. After the injection, no marked change in the blood pressure was noted. During the operation, a total of 5.7 ml of mepivacaine solution was administered for pain control. However, because of insufficient pain control, we added 2.2 ml of 2% lidocaine solution containing 1/160,000 adrenaline. The operation was completed without any adverse events, and no complications occurred after the operation. The administration of adrenaline should be avoided as much as possible because its addition along with endogenous catecholamine from the pheochromocytoma could cause severe hypertension. Therefore, when a local anesthetic containing adrenaline is administered for dental treatments or oral surgeries in patients with pheochromocytoma, it should be carefully injected while monitoring the patient’s blood pressure and pulse.