Sen. Tim Johnson continues to recuperate from brain surgery without complications, the Senate's physician said Thursday, a day after he was admitted to a Washington, D.C., hospital suffering from stroke-like symptoms.
"Senator Tim Johnson has continued to have an uncomplicated post-operative course. Specifically, he has been appropriately responsive to both word and touch. No further surgical intervention has been required," U.S. Capitol attending physician Adm. John Eisold.
Earlier in the day, incoming Senate Majority Leader Harry Reid, D-Nev., would not say whether Johnson was conscious or any other aspects of his medical condition, but told reporters that Johnson "looked great" after undergoing successful surgery for the congenital condition that causes tangled blood vessels.
Outgoing Senate Majority Leader Bill Frist, who is a surgeon, visited Johnson on Thursday afternoon and said he's "very pleased with the progress" the patient was making.
Reid said based on what he saw, Johnson will not be waylaid from serving in the Democratic-controlled Senate next year.
"I saw him, he looked great. To me, he looked very good," Reid said in a press conference on Capitol Hill after returning from visiting Johnson.
Johnson was admitted Wednesday afternoon after a condition from birth, called arteriovenous malformation, caused bleeding in his brain, Eisold said.
"He (Johnson) underwent successful surgery to evacuate the blood and stabilize the malformation," Eisold, who is consulting with surgical doctors at the hospital, said Thursday morning. "The senator is recovering without complication in the critical care unit at George Washington University Hospital. It is premature to determine whether further surgery will be required or to assess any long term prognosis."
Johnson's condition, also known as AVM, causes arteries and veins to grow abnormally large and become tangled. The congenital condition causes tangled blood vessels.
"An arteriovenous malformation is an abnormal connection between an artery and a vein that you're born with,” said Dr. Thomas Lansen, a New York neurosurgeon, who was not part of the surgical team. The amount of blood and pressure in the brain and the location of the blood clot will determine how much damage was caused, Lansen said.
Details of the surgery were not disclosed by the hospital, except that it began Wednesday night and lasted past midnight. Sen. Dick Durbin, D-Ill., the No. 2 Democrat in the Senate, said Reid called him around 3:00 a.m. CST to say Johnson had come through eight hours of surgery.
"The Johnson family is encouraged and optimistic. They are grateful for the prayers and good wishes of friends, supporters and South Dakotans," said Barbara Johnson, Johnson's wife, in a statement. "They are especially grateful for the work of the doctors and all medical personnel and GWU hospital."
Johnson was admitted on Wednesday around noon EST after wrapping up a conference call with reporters, in which he became disoriented and stuttered a response to a question. He appeared to recover, asking for any additional questions and then signed off.
According to a spokeswoman for the senator, Johnson did not suffer a stroke or heart attack. His office had said earlier it was a possible stroke.
But several hours after she spoke, John Eisold, the Capitol physician, called that into question with a statement of his own.
"Senator Tim Johnson was admitted to the George Washington University Hospital today with the symptoms of a stroke. He is currently under the care of physicians at the George Washington University Hospital," Eisold said.
Johnson spokeswoman Julianne Fisher said the senator was taken to the hospital after walking to his Capitol Hill office following the conference call. The Capitol physician came to his office and examined him, and it was decided he needed to go to the hospital.
"It was caught very early," she said.
Johnson, who turns 60 on Dec. 28, is a cancer survivor, having had his prostate gland removed in March 2004. According to news reports, he is also deaf in his left ear as a result of surgery to remove a benign tumor from his eardrum after returning from the Vietnam War.
While the extent of his illness isn't known yet, Washington political watchers are already noting that a Johnson replacement in the Senate would be made by Republican Gov. Michael Rounds. Sources in South Dakota told FOX News contributor Mort Kondracke that Rounds is inclined to name a Republican replacement should the need arise.
South Dakota Secretary of State Chris Nelson said no special restrictions are put on such an appointment and a replacement does not have to be in the same political party. But Nelson added that the law applies differently for a senator than a representative.
"If there is a vacancy, the governor appoints a replacement and that person serves until the next general election," Nelson said. The next general election would be 2008. The governor would only call for a special election in the event that a congressman died, Nelson said.
With the 110th Congress split 49 Democrats, 49 Republicans and two independents that align themselves with the Democrats, majority control of the Senate could shift in the event Johnson is incapacitated. One former lawmaker chastised the political playmakers in town for discussing such options so quickly after Johnson was hospitalized.
"This is a pretty mean town and let's just keep him in our prayers," said former House Majority Leader Tom DeLay, R-Texas. "This town is so eat up with power that everybody, you know, that's all they think about. You go to ask somebody for a cup of coffee, they question why you asked, there must be an ulterior motive to you asking.
"Senator Johnson is a really nice man from strong South Dakota stock so I am sure he'll be all right," DeLay added.
The White House also issued a statement wishing the senator a speedy recovery.
"The president and first lady have Senator Johnson and his family in their thoughts and prayers and they wish him a full and speedy recovery," said spokeswoman Dana Perino.
Reid, D-Nev., the incoming majority leader, visited Johnson at the hospital after learning about the senator's condition around 1 p.m. EST Wednesday. Reid suffered a mild stroke-like event in August 2005. He was not hospitalized and was diagnosed with having had a transient ischemic attack —- a brief interruption in the blood supply to a part of the brain. It can be a sign that someone's at risk later in life for a stroke.
Reid went back to the hospital Wednesday night to visit Johnson with Sen. Byron Dorgan, D-N.D. Fellow South Dakotan and former Sen. Tom Daschle also visited Johnson at his bedside.
"This is a very serious situation," a Reid spokesman said. On Thursday, Reid returned as did Dorgan, Daschle and Johnson's son.
Numerous Senate Republican sources told FOX News on Thursday that no huddling, planning or other calculations are being made about a possible change in the power structure as a result of Johnson's hospitalization. They said the reasons for that are to avoid any appearance of capitalizing from a tragedy for Johnson and his family and because unless Johnson dies or sends a letter to the secretary of the Senate declaring his incapacitation, the balance of power remains as it is.
Republicans say they will make no effort to challenge Johnson's role in the Senate during his illness.
"There isn't a thing that's changed. The Republicans selected their committees yesterday. We've completed ours. I have a very busy schedule today, going ahead and getting ready for the next year," Reid said of the machinations on the Hill.
"We have a majority of one so every person in the Senate is an important part of that calculation," Durbin conceded.
According to CQ Today, a Capitol Hill magazine, several lawmakers have been derailed by illness and unable to vote, but have not given up their posts and eventually returned to office. Sen. Joe Biden, D-Del., suffered an aneurysm and had brain surgery in February 1988. He returned to office seven months later and is still serving.
Former Sen. David Pryor, D-Ark., suffered a heart attack in April 1191 and returned to the Senate in September of that year.
The late Sen. Karl E. Mundt, R-S.D., refused to resign after suffering a stroke in November 1969. He stayed in office until the expiration of his term in January 1973, though he was unable to serve and fellow lawmakers stripped him of his committee assignments and seniority in February 1972.
Johnson was first elected to the Senate in 1996, and defeated John Thune in his 2002 re-election by 524 votes. Thune then joined him in the Senate after defeating former Sen. Tom Daschle in 2004.
Johnson served in the House for 10 years prior to that, focusing his attention toward the committees on Indian affairs and energy and natural resources as well as appropriations. The latter allows him to direct funds to South Dakota.
Johnson has worked as a lawyer and county prosecutor and served several years in the 1970s and 1980s in the South Dakota state Legislature.
FOX News' Major Garrett, Trish Turner, Molly Hooper and Israel Balderas and The Associated Press contributed to this report.