Sen was put on non-invasive ventilator support after her condition deteriorated two days back at the critical care unit of a city nursing home.
Though her oxygen saturation has improved since Friday, it still needs "continuous monitoring", said the latest medical bulletin.
"Because her health condition is fluctuating...we can't say that she is out of danger yet," said Subrata Maitra, member of the team of seven experts monitoring Sen at the Belle Vue Clinic here.
Sen's breathing problem worsened Friday, with her oxygen saturation dipping, thereby necessitating the ventilator support. Though her condition stabilised Saturday, owing to the continuously fluctuating oxygen saturation she was put on intermittent non-invasive ventilation.
"She remains conscious but little weak," said the release.
"Her other vital parameters like heart rate and blood pressure are stable," said the release.
"We are thinking of ending the course of antibiotics. Our aim is to clear the fluids and secretions that have accumulated in the respiratory tract," said Maitra.
The 82-year-old has been on nasal oxygen (through a flexible plastic tube) at her residence for the last few years.
She is receiving chest physiotherapy and her health condition has been reviewed by two chest specialists.
The veteran actress was undergoing treatment for a chest infection at the nursing home since Dec 23 and was taken to the CCU after her condition worsened Dec 28 night.
She is known for her performances in films like "Deep Jwele Jaai" and "Uttar Falguni" in Bengali as well as Hindi movies such as "Devdas", "Bombai Ka Babu" and "Mamta". She won the best actress award for "Saat Paake Bandha" at the Moscow Film Festival in 1963.
The mother of actress Moon Moon Sen quit acting in 1978. Since her retirement, she meets only a few people, including her daughter as well as granddaughters Raima and Riya Sen.
--IANS (Posted on 05-01-2014)