Sen. Edward M. Kennedy is not expected back at work in the Senate this week, Democratic officials said Monday as doctors searched for the cause of the weekend seizure that sent the 76-year-old lawmaker to the hospital.
There was no word on how long Kennedy would remain hospitalized. Physicians not involved in his care debated whether the length of his stay was an indication of something more serious or simply an outgrowth of caution in dealing with a prominent patient.
President Bush telephoned Kennedy at Massachusetts General Hospital with get-well wishes Monday. "Take care of my friend," he told Kennedy's wife, Vicki, according to a family spokesman. The senator was unavailable to take the call.
"The senator and Mrs. Kennedy were very appreciative of the call," spokeswoman Stephanie Cutter said. Over the weekend, Kennedy fielded similar calls from Sen. Barack Obama of Illinois and others, while receiving visits from Sen. John Kerry of Massachusetts, other dignitaries and a stream of family members.
The Senate is scheduled to begin a Memorial Day vacation at the end of the week, and several officials said they did not expect Kennedy back at his desk until after the break. They also said the expected absence did not indicate a more serious illness than Kennedy's office has disclosed.
The liberal icon was admitted to Massachusetts General on Saturday after becoming ill following a walk with his dogs at his oceanfront home on Cape Cod.
While Kennedy suffered what first appeared to be stroke-like symptoms, the senator's primary care physician, Dr. Larry Ronan, later said preliminary tests had ruled out a stroke and Kennedy appeared to have been the victim of a seizure, an electrical disturbance in the brain. Ronan and other physicians were conducting a battery of tests, the results of which may not be available until Tuesday.
Kennedy underwent surgery last October on the left carotid artery in his neck after doctors discovered a near-complete blockage that left him with an elevated risk of a stroke. The senator has since resumed a hectic schedule, including campaigning for Obama and bouncing between appointments on Capitol Hill and in Massachusetts.
Dr. Mark Schlosberg, a neurologist affiliated with the Washington Hospital Center, said if Kennedy were his patient he would investigate whether he suffered an undetected stroke during his surgery, since seizures can often come months after a stroke.
"Perhaps he didn't have any symptoms of a stroke at that time, but maybe it put him on the path to a seizure down the road," Schlosberg said. CAT scans, MRIs, blood tests and an EEG brain-wave test would also be used to search for evidence of a stroke, brain tumor or abnormal brain activity such as a seizure.
Schlosberg said seizures can also be caused by medication, undiagnosed diabetes or sudden alcohol withdrawal. The duration of Kennedy's hospitalization raised questions for him.
"From my experience in the hospital where I work, when someone comes in with a seizure and is admitted, this can all happen within a day. There can sometimes be logistical issues — the attendant comes for the MRI and the patient is in the EEG — but this can all usually be done within a day," Schlosberg said.
Doctors may be taking more time, he said, because they know there will be a public scrutiny of Kennedy's treatment.
But Dr. Steven Schachter, a neurology professor at Harvard Medical School, said diagnosis "is not always a linear process." Physicians sometimes have to circle back to earlier test results as they glean new clues from subsequent tests or fresh elements of a patient's medical history.
He said one major focus would be determining whether Kennedy actually had a seizure, and if so, whether it's the type of seizure likely to recur.
"One of the problems is that there are so many different causes of a seizure, so there isn't any single evaluation or work-up or predictable time course or series of events that we can look for from the outside. We really have to wait to see what was found and what the implications of that are," Schachter said.