The health department has told hospitals and the authorities managing “safe homes” to ensure adequate supply of oxygen, officials said.

At the state-run MR Bangur Hospital in Tollygunge, for instance, the daily oxygen requirement was around 50,000 litres in the pre-Covid times.

Now, the demand varies between 1.5 lakh and 2 lakh litres. MR Bangur is a dedicated Covid hospital.

At safe homes stay Covid patients with mild to moderate symptoms, who may suddenly need oxygen support.

“When the coronavirus infects the lungs, it usually results in shortage of oxygen,” said pulmonologist Sumit Sengupta. “In order to make up for the shortage created by the viral infection, oxygen needs to be supplied from outside. It is not a treatment but support.”

Health department officials said uninterrupted supply of oxygen was emerging as the most important “life-saving support” for many Covid-19 patients with lung infection.

“We have asked hospitals and authorities of safe homes to make arrangements for uninterrupted flow of oxygen,” said Gopal Krishna Dhali, the head of the department of gastroenterology at SSKM Hospital, who is leading the team of doctors for Covid-19 management.