Normal perfusion pressure breakthrough is a potentially catastrophic event after arteriovenous malformation (AVM) surgery. Anesthesia providers should strive for tight perioperative blood pressure control and should be vigilant for signs of postoperative neurologic deterioration. This chapter presents a case study of a 37-year-old female with a 2-month history of generalized tonic-clonic seizures. The patient underwent a successful left craniotomy for clipping and resection of an AVM located in the left parietooccipital lobe. Emergent computed tomography (CT) scan of the brain showed massive cerebral edema, as well as enlarged vascular enhancement suggesting hyperperfusion and a small intracerebral hemorrhage. One month after surgery, examination demonstrated no neurologic deficit and a cerebral angiography showed normalization of flows and diameter of the left posterior cerebral artery. Neuroimaging evidence of normal pattern of cerebral vasoreactivity along with neurologic status improvement may warrant barbiturate withdrawal and careful liberalization of the blood pressure control.