Former prime minister Thaksin Shinawatra's condition has not improved since he was transferred to the Police General Hospital for treatment.
Pol Lt Gen Dr Sophonrat Singhajaru, the hospital's chief physician, said on Friday an echocardiogram and lung tests showed Thaksin's heart and lung conditions were still a concern, while his blood pressure remains stable.
Thaksin, 74, was sent to prison on Tuesday after returning home from self-exile the same day, following a court appearance. He was transferred from Bangkok Remand Prison to the Police General Hospital at 12.20am on Wednesday after suffering from chest pain, hypertension and low blood oxygen, according to the Department of Corrections (DoC).
He is currently in an intermediate care unit (IMCU) room on the 14th floor of the Maha Bhumibol Rachanusorn 88 Phansa Building. He is able to communicate, Pol Lt Gen Dr Sophonrat said, adding that all medical reports have been sent to Ayuth Sintoppant, the DoC director-general, but he could not confirm how long he will remain in the hospital.
Regarding rumours Thaksin would be transferred to a privately run hospital, the doctor said he would not be transferred as the Police General Hospital has the capacity and equipment to treat him unless it is requested by the DoC.
Details of Thaksin's treatment cannot be disclosed due to patient privacy laws, said Pol Lt Gen Dr Sophonrat.
"The hospital only has a duty to treat patients and has nothing to do with security or politics," he said.
Requests to visit Thaksin must also comply with DoC regulations, he added. Pol Lt Gen Achayon Kraithong, Royal Thai Police spokesperson, told the media that security arrangements for visits have not yet been discussed.
Meanwhile, outgoing deputy prime minister and acting justice minister Wissanu Krea-ngam responded to a question about a royal pardon for Thaksin, saying he can submit a request while in hospital.
Asked if Thaksin might be sent to a private hospital, Mr Wissanu said there was no reason to do so.