Concern seen on recovery, survival

Israeli Prime Minister Ariel Sharon faces tough odds of surviving the massive stroke he suffered on Wednesday, according to American stroke specialists who are not involved in his care.

If he does survive, the specialists said, he may retain his ability to communicate, because the stroke was on the right side of his brain.

However, the apparent extent of the bleeding suggests that there may be extensive damage to his brain as a result of the stroke, caused by a burst blood vessel, doctors said.

Damage on the right side of the brain may result in paralysis of the left side of the body; speech is controlled by the left side of the brain. The full extent of his injuries will not be known for days.

Dr. Shlomo Mor-Yosef, director of the Hadassah Ein Kerem Hospital, in Jerusalem, said yesterday that doctors plan to keep Sharon, 77, in a coma for at least two days to reduce pressure on his brain.

After that, they will gradually wake him and begin mental tests to determine damage. Already, the hospital chief said, Sharon's eyes are responding to light, indicating that his brain is functioning.

Last night, Sharon remained in the Hadassah Ein Kerem Hospital's intensive care unit, after two sessions of surgery on Wednesday night and into yesterday morning.

Strokes that involve bleeding into the main part of the brain, as Sharon's did, can be deadly.

Only about 25 percent of patients survive a month after large bleeds, those involving about a quarter of a cup or more of blood, according to medical reference books.

Doctors have not said how much blood was found in Sharon's brain. The risk of death comes not only from the blood in the brain, but also from the possibility of brain swelling, pneumonia, heart attack, and blood clots in other parts of the body.

''The fact that he had a second operation to control more bleeding suggests a very severe brain injury," said Dr. Lee H. Schwamm, director of acute stroke services at Massachusetts General Hospital. ''Most stroke patients over 75 who require surgery end up being fairly disabled."

Many, he said, are so disabled that doctors recommend merely keeping them comfortable.

The type of event that Sharon suffered, called a hemorrhagic stroke, accounts for only about 15 percent of all strokes. Patients who survive these strokes often recover more function than those who suffer the more common and less deadly type caused by a blood clot in the brain, according to Dr. Judith Hinchey, director of the stroke service at Caritas St. Elizabeth's Medical Center.

Sharon suffered one of these ischemic strokes in the middle of December. At that time, doctors treated him with clot-busting drugs, and put him on an injected blood-thinning drug to prevent additional clots, a typical treatment.

They also scheduled surgery to close a hole in Sharon's heart.

That surgery had been scheduled for yesterday, but was preempted by his second stroke.

Neurologists said the blood-thinning drug likely worsened the second stroke, but probably did not cause it. Blood thinners can cause bleeding if a patient takes too much, but Sharon was under close supervision.

More typical causes of strokes involve burst blood vessels resulting from chronic high blood pressure, that leads to bulges in the blood vessels, malformed connections between arteries and veins, and a weakening of blood vessels.

Israeli doctors said Sharon does not suffer from high blood pressure, although he is overweight; the doctors have not talked about other possible causes.

Some patients who suffer clot-related strokes have hemorrhages in the same area of the brain, when normal blood flow is restored.

When Sharon arrived at the hospital Wednesday, doctors rushed him into surgery after discovering the brain bleeding on a magnetic resonance imaging scan. Surgery is not standard treatment in such cases, unless the bleeding is so severe that the patient's life is in jeopardy, according to Hinchey.

''There's very little evidence that surgery helps with the outcome," she said. ''It will certainly help you survive, but the deficits won't change."