Whats considered a severe stroke?

Disabling: If one has a stroke, and was a lawyer, loss of speech is a "severe stroke". If a patient has an intracerebral bleed, there is a 60% chance of death in one year, and this would be "severe". A complete paralysis on one side, "hemiplegia" is considered severe. Complete obstruction of a major blood vessel, or impact on the brainstem area can have devastating consequences.

When function is out: To my knowledge there's no formal definition on the descriptors "mild, moderate, severe" as applied to stroke. I'd define a SEVERE stroke as being one which significantly or permanently affects function of a body part(s) or ability (such as speech or vision) & how that person ultimately recovers and manages their lives afterward. Others may choose to define it other ways.

Several levels: Death, unable to speak- aphasia. Paralyzed- hemiplegic, Disabled Decreases in mental functioning.

Stroke: A stroke means that the blood supply to a part of the brain is suddenly cut off. The brain cells need a constant supply of oxygen from the blood. Soon after the blood supply is cut off, the cells in the affected area of brain become damaged or die. A stroke is sometimes called a brain attack. http://patient.info/health/stroke-leaflet