Bhattacharjee was admitted to the Intensive Care Unit of the privately-run Woodlands Hospital here on Friday night with severe shortness of breath, low oxygen saturation and high carbon dioxide levels in the blood.
The doctors diagnosed his condition as acute exacerbation of chronic obstructive pulmonary disease (COPD) with pneumonitis in both lungs and anaemia. He is on non-invasive ventilation (bipap), intravenous antibiotics and nebulisation and is undergoing chest physiotherapy to clear the congestion. He was also given a blood transfusion.
An eight-member medical board reviewed Bhattacharjeee's condition at 9 a.m. on Sunday. The patient's family members were also present during the review.
"Budddhadeb Bhattacharjee is now conscious, alert and talking. His vital parameters are stable. He is tolerating oral food and had ice cream, tea and papaya this morning.
"He is tolerating non-invasive ventilation (bipap) so far. He took bipap for nearly six hours last (Saturday) night," a doctor told the media.
Bhattacharjee's chest x-ray showed signs of resolution and improvement of pneumonitis.
His haemoglobin level has risen to ten gram per decilitre. Carbon dioxide level has come down, though he will continue to need oxygen, they said.
To a question as to whether the doctors were planning a CT scan, one of the attending doctors said: "We are considering that, but no final decision has been taken."
Bhattacharjee has been suffering from progressive lung problem COPD for years. He also has diabetes.
Governor Jagdeep Dhankar and Chief Minister Mamata Banerjee visited the 75-year-old Bhattacharjee at the hospital on Friday night.
Bhattacharjee, who was the Bengal Chief Minister during 2000-2011, undertook an all-out industrialisation drive for reducing unemployment in the state but the measures proved counter-productive.
As his government tried to acquire large tracts of land for setting up industries, the farmers revolted, and the Trinamool Congress fanned the discontent to gain popularity and finally came to power in 2011 ending 34 years of Left Front rule.
Bhattacharjee was last seen in public on February 3, when he went to the Brigade Parade ground to attend a rally called by the Left Front.
( With inputs from IANS )