Case Report A Rare Complication of Trigeminal Nerve Stimulation During Radiofrequency Thermocoagulation Sudden ST Segment Elevation *Hu ˆlya Bi . lgi . n, *Nermin Kelebek, *Gulsen Korfali, †Ahmet Bekar, and *Beklen Kerimog ¯lu Departments of *Anesthesiology and †Neurosurgery, Uludag ˘ University Medical School, Bursa, Turkey Summary: Coronary vasospasm resulting from a sudden autonomic response associated with an intracranial procedure was encountered during percutaneous radiofrequency trigeminal rhizotomy. Although it is very rare, careful monitoring and readiness for the occurrence of such a potentially lethal situation with necessary medications may prevent a fatal outcome. Key Words: Trigeminal rhizotomy—Coronary vasospasm— Nitroglycerin Percutaneous radiofrequency (RF) trigeminal rhizoto- my is a commonly used, effective treatment for refractory trigeminal neuralgia. The procedure is usually performed on an outpatient basis, with few complications. Mortality from this procedure is rare. The most common complica- tions are facial numbness or dysesthesia, corneal anesthe- sia, and masseter muscle weakness (1–3). However, there have been a few reports of ventricular fibrillation and coronary vasospasm after the development of ST segment elevation in electrocardiogram (ECG)(4,5). We report a case of transient ST segment elevation that occurred dur- ing percutaneous RF trigeminal rhizotomy. CASE REPORT A 79-year-old woman presented with a 20-year history of trigeminal neuralgia of the right trigeminal nerve. Ra- diofrequency trigeminal rhizotomy was performed twice under local anesthesia, supplemented with sedation, with- out any complications. Twelve months before presenta- tion, when her systems reappeared, she was subjected to carbamazepine treatment. Because the treatment was ineffective, the patient was scheduled for RF trigeminal rhizotomy. The patient had no history of angina pectoris, dyspnea on exercise, hypertension, smoking, or hypercholesterol- emia, nor was there a family history of heart disease. She was on oral carbamazepine therapy only, 600 mg daily. Her electrocardiogram (ECG) revealed normal sinus rhythm without any sign of coronary artery disease, and her chest radiographs were normal. Monitoring in the operating room during the procedure included an ECG lead II, noninvasive blood pressure, end- tidal CO 2 , and respiratory rate. Oxygen saturation was measured by pulse oximetry. Oxygen was administered via a nasal catheter, 3 L/min. The patient’s mean blood pressure and heart rate were 125 mm Hg and 88 beats/min respectively. Intravenous midazolam, 0.03 mg/kg, and 7.5 g/kg intravenous alfentanil were administered for sedation to the unpremedicated patient, followed by 15 Address correspondence and reprint requests to Hu ¨lya Bi . lgi . n, M.D., Uludag ˘ University Medical School, Department of Anesthesiology, 16059 Göru ¨kle, Bursa. Accepted for publication August 22, 2001. Journal of Neurosurgical Anesthesiology Vol. 14, No. 1, pp. 47–49 © 2002 Lippincott Williams & Wilkins, Inc., Philadelphia 47