Strokes are like Rodney Dangerfield--they just don't get any respect. Odd, considering that for the usual stroke victim, it's the most serious illness of their life.
Although stroke is the third-leading cause of death in the U.S. and the number one cause of disability, this condition doesn't get the respect and attention it deserves. When people have sudden chest pain, they know they might have a heart attack. They call 9-1-1 and seek help immediately. But people who suddenly become weak or numb on one side of their body, or experience sudden problems with speech or vision, often act unhurried in seeking help.
Why is this? One possibility is that heart attacks are usually painful. Strokes are not necessarily painful, and even when pain is present, it can be mild. Pain is a powerful motivator, and some people have the mistaken belief that all serious medical conditions hurt, and the seriousness of the problem is proportionate to the intensity of pain. Also, because the brain is a more complicated organ than the heart, symptoms of strokes can also be more complex, making them harder to identify.
In both strokes and heart attacks a portion of a body-organ has experienced a sudden disruption of its circulation. Increasingly, strokes are called "brain attacks" to emphasize the parallel with heart attacks. As a neurologist, I sometimes describe a stroke as "a heart attack of the brain." Reflecting my bias as a brain specialist, I also describe a heart attack as "a stroke of the heart," but--what can I say?--this terminology hasn't caught on.
If you suspect stroke in another person, the American Stroke Association recommends a quick, 3-step, screening test to identify cases :
- Ask the person to raise their arms and keep them up. In many stroke victims one arm doesn't go up or, once up, sags.
- Ask the person to smile. A lopsided or one-sided smile can indicate trouble.
- Ask the person to repeat a simple sentence. If it comes out garbled or unclear-or not at all-a stroke is likely.
While it's better to have some system of detection than no system, this screen misses strokes affecting the parts of the brain involved in sensation or vision which are just as serious as strokes causing paralysis or loss of speech.
So now that emergency help has been summoned, what happens next?
The emergency squad, upon arrival, sizes up the situation and measures vital signs, including rate and adequacy of breathing, pulse rate and blood pressure. They insert an IV line, check the blood-sugar level via a finger-stick method, apply pads to the chest to monitor heartbeats, and often administer oxygen as well. Then they transport the patient to the nearest emergency department.
Upon the patient's arrival, the medical team obtains more history and examines the patient more thoroughly. They draw blood to measure blood-sugar, blood-counts and blood-clotting function, as well as other blood-chemicals, including those showing the presence or absence of a concurrent heart attack. They perform an electrocardiogram (EKG) and continue the process of monitoring vital signs and heart-rhythms initiated by the squad.
A computed tomographic (CT) scan of the head is usually done soon after the patient's arrival. CT scans can detect the 1-in-6 kind of stroke involving bleeding within the brain, but often fail to detect the more usual kind of stroke, called an infarction, caused by a blocked blood-vessel. This is because, in the first 24 hours, damaged brain-tissue can look just like healthy tissue to the scanner's x-ray beam. The CT scan also screens for other brain diseases, like brain tumors or infections, that might mimic a stroke, but call for completely different treatments.
So far, the discussion has been all about testing. What about treatment? What can be done to improve outcome, reduce the severity of the impairment and prevent death?
A useful way to think of a brain infarction is as a central core of forever-lost brain cells that no treatment can revive, surrounded by a larger zone of sick brain-tissue that may or may not recover. Early treatments focus on this surrounding tissue that is "on the bubble," trying to influence it to survive rather than die.
One dramatic but controversial treatment is to use an intravenous clot-busting drug called t-PA (tissue plasminogen activator). The potential benefit of using this drug is to reduce the eventual impairment of the patient caused by the stroke. However, the drug also increases the likelihood of brain-hemorrhage, and physicians are not unanimous in believing that the benefits of this treatment outweigh its risks. However, one point of agreement is that if t-PA is going to be used, it has to be administered within 3 hours of the stroke's onset. Arriving at the emergency room after 2 hours and 59 minutes isn't good enough because a clinical evaluation, CT scan and blood tests all need to be completed before the drug is infused.
Less dramatic treatments are every bit as important--and quite possibly more important--than use of a clot-busting drug. It's the simple things that often matter most, but because they're so simple, sometimes they are unappreciated or even forgotten.
One such treatment is to manage the body-temperature. Fever increases the size of the stroke, so when an elevated temperature is present, it needs to be decreased right away. Another little detail is to manage the blood-sugar. Oddly, an elevated blood-sugar is toxic to the oxygen-deprived but still-surviving brain cells. So the emergency team should aggressively treat elevated blood-sugars by administering insulin.
Yet another issue of crucial importance is to urgently treat severe anemia (decreased red blood cells) by transfusing blood. Oxygen molecules are transported to the brain attached to molecules of hemoglobin within red blood cells. So if there are fewer red blood-cells, less oxygen is delivered to the sick brain-tissue. Providing more red blood-cells increases oxygen-delivery.
Of course, if the patient's blood-pressure is severely elevated, it needs to be decreased, but mildly-to-moderately elevated blood-pressures might actually improve blood-flow to the damaged tissue. If the patient's blood-pressure is excessively low, this is bad, too, and is treated by infusing salt-water or administering medication. Dangerous heart-rhythms also need to be treated, as does a concurrent heart attack, when present.
The principal value of being in a hospital with a fresh stroke is to achieve clinical stability in a monitored environment where rapid interventions can be made when called for. The hospital also provides a setting in which more extensive tests can also be performed, though not necessarily in the first 24 hours, that seek to understand why the stroke occurred and what can be done to prevent another brain attack.
By : Gary Cordingley, MD, PhD
