During a dental appointment, a patient suddenly develops slurred speech, unilateral visual disturbance, and facial droop with a blood pressure of 200/90 mmHg. What is the most likely emergency?

A cerebrovascular accident (CVA/stroke) presents with sudden onset neurological deficits including slurred speech (dysarthria or aphasia), visual disturbances, facial asymmetry, arm weakness, and altered consciousness. The FAST acronym is used for recognition: Face drooping, Arm weakness, Speech difficulty, Time to call 911. Severely elevated blood pressure (200/90 in this case) is both a risk factor and a consequence of acute stroke. Management in the dental office: immediately stop treatment, call EMS, position the patient comfortably, monitor vital signs, and provide supplemental oxygen. Do not administer aspirin if hemorrhagic stroke is possible.