Prevention of Complications during Endovascular Surgery on the External Carotid Arteries, with Special Reference to Use of Nitropaste and the Lidocaine Test

Purpose To examine all complications of endovascular procedures on the external carotid arteries and to ascertain how to reduce their number. Methods In 93 consecutive patients, 137 endovascular procedures on the external carotid arteries were performed during the last 6 years. Results We encountered no neurologic complications in these patients. In eight (9%) of the 93 patients who underwent lidocaine tests of the external carotid branches, nine transient cranial nerve palsies occured, seven of 67 vessels (10%) involving the middle meningeal artery and two of 18 vessels (11%) the ascending pharyngeal artery. However, they soon disappeared and successful embolisations were achieved. Vasospasm that prevented endovascular procedures occurred in only two cases of this series as a result of the application of isosorbide dinitrate. Conclusions The lidocaine test effectively provoked cranial nerve palsies without false negatives. The complication rate of endovascular surgery will decrease as long as awareness of complications such as cranial nerve palsy is maintained.