Former Mayor Edward I. Koch, who has been hospitalized since Monday with lung problems, was placed in the intensive care unit on Thursday afternoon, his spokesman said.
Mr. Koch’s lead doctor “said he wanted to monitor the former mayor more closely,” said the spokesman, George Arzt, who declined to elaborate.
Mr. Koch, 88, is at NewYork-Presbyterian/Columbia hospital, where he has been a frequent visitor lately for a series of health problems.
He was treated for anemia in September, for a lung infection in December, and earlier this month for a buildup of fluid in his lungs. He was released last Saturday after being treated for the lung ailment, only to return on Monday because fluid in his lungs had built up again.