Critical Care and Neuroanesthetic Considerations for Arteriovenous Malformation and Arteriovenous Fistula Surgery

Critical care and anesthetic management are essential components of a multidisciplinary approach to the treatment of arteriovenous malformations (AVMs). Presenting symptoms of AVMs include hemorrhage, seizure, headache, and focal neurological deficits and will predict the most important first steps. Hemorrhage is the most common presenting event and requires cautious and rapid blood pressure control. Timing of surgical correction is debatable, with risk and benefits to both ultra-early resection and delayed treatment after rupture. Seizures are the most common presenting symptoms in unruptured AVMs and are treated with standard antiepileptic medications. While AVMs are a rare cause of headaches, most patients with AVMs have headaches. The least common presenting symptom is focal neurologic deficit. During open or endovascular repair, optimal control of blood pressure, intracranial pressure, ventilation, and oxygenation and monitoring are critical for the prevention of secondary brain injury, and assist the surgeon to optimize outcomes for these patients. Because of abnormal vasculature, cerebral tissues around the AVM are often under-perfused and are at risk of further ischemia in the setting of hypotension. Many anesthetics including inhaled medications can increase intracranial pressure and should be avoided. Additional brain relaxation can be accomplished with hyperosmotic therapy. Intraoperative monitoring with neurophysiologists can be complementary to anesthetic and surgical planning; short-acting paralytic agents are preferred if neuromonitoring will be utilized. Occasionally, awake craniotomies can be performed to preserve eloquent areas in appropriately selected patients. With careful alignment of the management of medical and surgical care, superior patient care can be achieved.