Dan Nowicki and Ken Alltucker

The Arizona Republic

PHOENIX — Arizona Sen. John McCain's sudden Friday cranial surgery to remove a blood clot has already roiled the Capitol Hill health-care debate and prompted questions about the gravity of his condition.

Medical reports about the nature of that clot could help answer another key question: Was the senator's confused questioning of former FBI director James Comey in a memorable Capitol Hill hearing last month an early warning?

The answer could come soon. Tissue pathology reports, standard after such a procedure, usually take 24 to 48 hours, and McCain's camp has indicated it will provide an update when it knows more.

Those results could either tamp down or further fuel speculation about McCain's condition. The New York Times on Sunday broached a possible connection to McCain's sluggish and distracted participation in the much-watched Senate Intelligence Committee's interrogation of Comey, whom President Trump fired May 9. NPR raised the question again Monday.

More:Sen. John McCain undergoes surgery for blood clot above eye

One neurosurgeon not involved in treating McCain sees the senator's prompt release from the hospital as a sign that things are less dire.

"People have tried to say, ‘Is this why he was acting strange a month ago during the hearings?' " said Dr. Joseph Zabramski, a neurosurgeon at Barrow Neurological Institute in Phoenix. "It wouldn’t make any sense because he was normal (after the hearing). I don’t think there was a connection between that episode and the present procedures."

McCain, 80, laughed off the June 8 episode, saying he'd stayed up too late the night before watching the Arizona Diamondbacks. But many were left wondering about the Arizona Republican's health.

McCain's team and the Mayo Clinic in Phoenix said the clot was “above his eye” and its removal required a craniotomy, meaning it was inside his skull.

Doctors not involved in McCain’s care said it’s difficult to say whether McCain faces further complications without the pathology findings. It could shed light on the cause of McCain's blood clot and whether follow-up treatment or additional recovery time is needed.

"The pathology report remains an important piece of information to complete the picture of how and why this happened," said Dr. Martin H. Weiss, a professor of neurosurgery at the University of Southern California’s Keck School of Medicine and an expert in brain surgery.

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Without the still-pending results, doctors said it’s hard to speculate on McCain’s medical condition because of the vague description of the procedure in the Mayo Clinic's original statement.

But given McCain’s past bouts with melanoma, doctors will need the tests to ensure that cancer has not resurfaced and spread. The pathology tests could provide critical information on that front.

Unknown is the size of the blood clot. While the Mayo Clinic described it as a 5-centimeter (nearly 2-inch) clot, the most important measurement for doctors is the volume, Zabramski said.

Weiss, who said he assumes and hopes that McCain’s recovery will be uncomplicated, called it a positive sign that McCain returned home one day after the procedure. However, he cautioned that drawing any conclusions about this health status based on the publicly released information is speculation at this point.

The forthcoming pathology results may reveal any lingering health concerns, he said.

Others suggested that the Mayo Clinic’s description of the procedure could suggest the possibility of a subdural hematoma. That happens when blood pools between the brain and the dura mater, a thick membrane that surrounds the brain.

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Treating a subdural hematoma is among the most common procedures in neurosurgery.

Zabramski said even a minor trauma such as bumping your head while getting in a car can cause a subdural hematoma. The risk is higher in older adults.

Such an “acute” case could cause immediate symptoms such as headaches.

A longer-term blood clot that liquefies can stay and grow in the space between the dura and the brain, and place pressure on the brain, which could trigger problems such as weakness on one side of the body and seizures.

A larger blood clot could cause a person to have cognitive trouble, but Zabramski doubts that’s what afflicted McCain. Zabramski said patients with larger clots are typically monitored for days in the hospital after surgery, not released home the day following surgery as McCain was.

“McCain was operated on Friday and released Saturday,” Zabramski said. “This implies a relatively minor operation."

McCain has signaled he plans to take off only one week from his Senate work to recuperate.

Initially, it looked like his presence was pivotal to action on Republican-backed Senate health-care legislation, which Senate Majority Leader Mitch McConnell, R-Ky., decided to postpone until his return to Capitol Hill. However, support for the GOP bill fell apart Monday even without McCain, potentially easing pressure on McCain to rush back to Washington, D.C., although McConnell now is pursuing a vote to repeal the Affordable Care Act outright without an immediate replacement.

More:John McCain: GOP health care bill likely 'dead'

McCain traditionally has been forthcoming about his medical history, particularly during his 2000 and 2008 runs for president.

In May 2008, McCain's presidential campaign invited select national media to review 1,173 pages of documents dating from late 1999 to earlier that year in what it called an unprecedented disclosure of medical records in a political campaign.

He also allowed three of his doctors from the Mayo Clinic in Arizona to field questions from the media about his physical and mental fitness.

At the time, most of the attention was on his four separate bouts with melanoma, a sometimes deadly form of skin cancer. In August 2000, he had a dangerous, 2.2-millimeter-thick melanoma cut from his left temple, leaving a noticeable scar.

The 2008 document inspection also revealed that McCain took aspirin to stave off blood clots.

McCain will turn 81 on Aug. 29. His father, the late Navy Adm. John S. "Jack" McCain Jr., died in 1981 at age 70. His mother, Roberta McCain, is still living at age 105.

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