Kelly Martin of the University of Cincinnati Medical Center says Warmbier remains in a coma after arriving at the hospital two days ago.
Doctors plan to provide an update on his condition Thursday afternoon.
In Cincinnati, Warmbier criticized the world's approach to North Korea.
Fred Warmbier told Fox News' Tucker Carlson on Wednesday that his son, Otto, was "terrorized and brutalized" during his 17-month detention and has been in a coma for more than a year. According to reports in the Washington Post and other USA media, Yun went to see Warmbier immediately after arriving in Pyongyang on the morning of June 12, accompanied by two doctors.
After restating the question for other reporters who could not hear it, Warmbier gave a quick answer.
Warmbier was detained while on a tour of North Korea with a company called Young Pioneer Tours, which openly advertises on its website that "North Korea is probably one of the safest places on Earth to visit".More news: Shivraj observes fast to restore 'peace', Congress slams him
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That was used as evidence in his hourlong trial. It was the last time he was seen publicly before this week.
(AP Photo/John Minchillo). Alison Lebrun helps tie blue-and-white awareness ribbons along Springfield Pike near the family home of Otto Warmbier, a 22-year-old University of Virginia undergraduate student who was imprisoned in North Korea in March 2016.
"They have our thanks for bringing Otto home", he said.
When asked whether then-President Barack Obama could have done more, Fred Warmbier replied, "I think the results speak for themselves".
The 56-year-old Rodman, who won five National Basketball Association championships as a player with the Detroit Pistons and Chicago Bulls, previously traveled to North Korea in January 2014.
Fred Warmbier said he does not know exactly what happened to his son during his detention. The US and North Korea have been taking part in intense deliberations in Oslo, Norway, and in NY since last month for the release of Warmbier and other Americans detained in the North. "That's not my goal right now", he said. "But for you guys to come back here in your country, with a medal, that says a lot about North Korea, because people don't really take North Korea so seriously about sports or anything like that".
Three other Americans remain incarcerated in North Korea, and there are huge efforts by the administration to have them released.