MIDDLEBURG HEIGHTS, Ohio -- A man found dead on a couch in a hospital lounge may have been there more than 23 hours, and a nurse told police no one checked on him because they thought he was sleeping.

Police said Robert F. Johnson, 55, of nearby Berea, died at Southwest General Health Center in this southwest Cleveland suburb in a room near the second-floor intensive care unit.

"Nobody checked, nobody bothered to say excuse me? are you here for somebody," his wife, Robin Johnson said.

A hospital spokeswoman, Kelly Stanford, declined to comment on the death.

"It's an unfortunate situation," Stanford said, "but we're cooperating fully with all levels of investigation."

A nurse discovered at 10:30 a.m. Thursday that Johnson had died. The nurse told police that Johnson, who was fully dressed and curled with his face buried in a cushion, appeared discolored and was cold to the touch.

The same nurse also had seen Johnson on the same couch 17 hours earlier and had assumed he was sleeping, police said.

Another nurse told police she saw a man reclining on the couch at 11 a.m. on Wednesday.

Police Chief John Maddox said Johnson probably had been dead for several hours and most likely died of natural causes. The Cuyahoga County coroner's office planned to do an autopsy Saturday.

Johnson, whose only known medical problem was emphysema, had left his Berea condo on Monday morning after an argument, Robin Johnson said. She said that was the last time she saw him alive.

Maddox said he suspects that Johnson may have camped out at the hospital rather than return home. Johnson had placed his cell phone, an inhaler and eyeglasses on a coffee table near the couch where he died.

Robin Johnson said her husband had spent a night at the hospital in February, when she underwent open-heart surgery.

"It's logical to deduce that he could sleep there without being disturbed, as he had done in the past," Maddox said.

Middleburg Heights authorities are investigating.