Condemning the death of three patients in Government Rajaji Hospital in Madurai on May 7 night allegedly due to disruption in the supply of oxygen owing to a power cut, an association of doctors has demanded an investigation into the incident.

In a statement issued, the Doctors' Association for Social Equality (DASE) demanded an honest probe into the incident saying that unscheduled power cuts across the state are affecting government hospitals and hence uninterrupted power supply connections should be provided there.

DASE said operation theatres should be connected to separate generators and uninterrupted power supply systems. "The three patients who were in the ICU died of natural causes on Tuesday night. They had developed cardiac problems - common in the case of severe head injuries," the hospital's dean K. Vanitha told IANS over phone on May 8.

"It is true that there was a power cut in Madurai yesterday (Tuesday) evening and the hospital's diesel power generator failed to kick in immediately. But all the three patients were on ventilators which were connected to batteries having power back-up of two hours," she said.

Vanitha said that the ventilators and the battery power back-up were working well and hence the deaths were not due to disruption in the supply of oxygen or lack of power. "The battery connected to the ventilators was serviced and about eight to nine patients were connected to the ventilators at that point of time... the remaining patients are fine," she said.

Relatives of the three patients had alleged that they died due to breathlessness owing to lack of oxygen supply. Asked about the three patients dying within a span of 10-15 minutes, Vanitha said that such things happen in the hospital as there are over 2,000 in-patients and over 10,000 people coming as out-patients daily.

People suffering from serious head injuries from nearby districts are also brought in for treatment, she added. Vanitha also said that only three deaths occurred when the power supply was cut and news reports saying five patients lost their lives were wrong.