CHICAGO (Reuters) - Senator Mark Kirk of Illinois underwent surgery on Monday after suffering a stroke and is under sedation in a neurological intensive care unit, a physician for the Republican lawmaker said.
Surgeons at Chicago's Northwestern Memorial Hospital removed a portion of the 52-year-old Kirk's skull to relieve pressure from post-stroke brain swelling, and said he had "tolerated that surgery very well."
Kirk, formerly a five-term member of the House of Representatives, won election in 2010 to President Barack Obama's old Senate seat, which was vacant.
The ischemic stroke, which is when blood flow is impeded by a blockage, in this case through the carotid artery, impacted the right side of Kirk's brain.
"It will affect his ability to move his left arm, possibly his left leg, and possibly will involve some facial paralysis," said Northwestern Memorial Hospital neurosurgeon Dr. Richard Fessler, who performed the surgery.
Had it happened on the left side of his brain, Fessler said "it would have affected his ability to speak, understand, and think. So we're very hopeful that when we get through his recovery, all of those functions will be intact."
"We're happy with his current status," Fessler told reporters, adding that Kirk can recognize people when he is not sedated.
Kirk checked into a hospital in the northern Chicago suburb of Lake Forest, Illinois, on Saturday, suffering from headache and dizziness, and was transferred to Northwestern Memorial Hospital.
Kirk aide Richard Goldberg delivered to reporters a statement from Kirk's family thanking doctors at both hospitals for the "excellent treatment and care" they provided and thanking family and friends for their support.
"We are confident that the fighter in him will prevail," Goldberg said.
Kirk's office, in a statement on Monday, expressed optimism about the Senator's recovery.
"Due to his young age, good health and the nature of the stroke, doctors are very confident in the Senator's recovery over the weeks ahead," Kirk's office said in a statement.
Kirk, a U.S. Naval Reserve pilot who has flown missions over Iraq, is viewed a moderate Republican. He has pressed the administration on enforcing strict sanctions on Iran aimed at thwarting the country's nuclear ambitions.
Kirk, a native of Champaign, Illinois, was first elected to the House of Representatives in 2000 and narrowly beat Illinois Treasurer Alexi Giannoulias for the Senate seat.
Kirk recently endorsed former Massachusetts governor Mitt Romney in the nominating process to select a Republican to challenge Obama for the White House in 2012.
"I am extremely distressed by the news that my friend Mark Kirk is hospitalized for emergency medical treatment. I wish him a speedy recovery and a swift return to the U.S. Senate chamber," Romney said in a statement.
Additional reporting by Andrew Stern in Chicago; editing by Paul Thomasch