The health condition of former West Bengal chief minister Buddhadeb Bhattacharya improved slightly though he remained critical on Sunday morning, doctors treating him at a city-based hospital, said.

The oxygen saturation of the 79-year-old Bhattacharya, who was rushed to the private hospital from his Palm Avenue residence via a green corridor on Saturday afternoon, improved slightly, but he continued to be on invasive ventilation, a senior doctor said.

"His health condition remained critical but stable as oxygen saturation in his blood improved. His blood pressure has also improved. He is responding to the treatment but still is not out of danger. Our doctors closely monitored him the entire night and there was no major deterioration," the doctor told PTI.

On Sunday at around 10 AM doctors are likely to re-examine Bhattacharya to decide their next course of treatment, he added.

"Blood pressure has improved and he is responding to treatment. We are hopeful that he will come out of this crisis," Bhattacharya's cousin Malavika Chatterjee said.

Bhattacharya was diagnosed with lower respiratory tract infection and Type 2 respiratory failure.

Besides, being on invasive ventilation doctors have given him antibiotics, and other supportive management.

Bhattacharya, who was the chief minister from 2000 to 2011, has been suffering from COPD (chronic obstructive pulmonary disease) and other old age-related ailments for quite some time.

Bhattacharya has been away from public life for the past few years due to his health.

He had stepped down from the CPI(M)'s politburo and the central committee in 2015 and gave up membership in the state secretariat in 2018. PTI SCH RG

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