The hallmark of a stroke is the sudden onset of one or more of several symptoms. An individual experiences loss of balance and coordination, possibly including the ability to walk. He has difficulty speaking or comprehending speech, and experiences visual disturbances, such as blurred vision or loss of vision. Confusion is another possible symptom because of the disruption in one or more aspects of cognitive functioning. Finally, a person who has suffered from a stroke experiences weakness, typically on one side of the body.
Spectrum of Stroke Severity
The National Institute of Health Stroke Scale (NIHSS) is used by physicians and medical professionals worldwide to assess the severity of a stroke. Familiarity with the scale offers a physician's perspective in terms of stroke symptom range and severity. For each of the tests, ratings are given based on the level of impairment presented.
First, the level of consciousness is assessed. The individual is scored for overall responsiveness, ranging from completely responsive to completely unresponsive or flaccid. Two questions are posed to the patient: what is the month and his age. In addition, the patient is given two commands to follow: open and shut the eyes and grip and release the unaffected side's hand.
Visual processing is scored in terms of gaze (normal, partial paresis, or complete paresis) and perceptual function (normal, partial loss in one eye, or partial to complete loss in both eyes). Facial symmetry is then evaluated for the appearance of droop (scored as normal, or with minor, partial or complete paralysis).
Motor function is examined in both arms and legs. The patients holds each arm and leg out and each case is scored as having no drift, partial drift, or no hold against gravity. Limb ataxia (lack of coordination) is then evaluated by asking the patient to complete multi-action sequences. They are scored as normal or with ataxia present in one or both limbs. Sensation is established by examining reaction to a pinprick as normal, partial, or not present.
Language skills are established throughout the interview as well as by asking the patient to explain what is happening in a picture presented, to read sentences aloud, and to name items. Evaluation ranges from normal comprehension to complete aphasia (no usable speech or auditory comprehension). Additionally, speech production is assessed for the presence of slurs.
Lastly, the patient is examined for extinction and inattention, formerly referred to as "neglect": the patient is scored as normal or as having moderate to severe inattention to one or more sensory modalities either on one or both sides of the body.
Letting the Physicians Do Their Work
Recognizing sudden behavioral changes exhibited within yourself or in someone you know, and acting fast, can result in a significant increase in the chance of recovery following stroke. If you suspect that a stroke has occurred, seek a formal medical evaluation and treatment as soon as possible. Knowledge about the NIHSS can be useful as a means for understanding the range and severity of deficits that may be experienced due to a stroke. But a formal medical evaluation must occur before the appropriate treatments can be administered.
Learning to Adminster the NIHSS
If you suspect that someone has had a stroke, the administration of the NIHSS may help you to identify the severity of the stroke. If you are a healthcare professional and are interested in learning or reviewing how to administer the NIH Stroke Scale for acute stroke assessment in order to benefit a home or work environment, consult the American Stroke Association website (see Resources).
