A 32-year-old homemaker who had undergone a kidney transplant at SSKM Hospital on Tuesday died on Friday afternoon, less than 36 hours after she fell off the bed in the cabin where she was recovering.

Even though the death certificate cited renal failure as the cause of Barnali Patra's death, family members alleged negligence by the nurses.

The family members said Patra's fall could have been prevented had the nurses taken the mandatory precaution of putting up the safety rails around her bed.

"She was alone in her cabin ' Recovery Room 1 ' while the nurses on duty were sleeping in another room," said Anadi Patra, the patient's husband.

"The patient's relatives came to my office on Thursday and complained that she had fallen off the bed because of the nurses' negligence. I asked them to give me a written complaint, which they did. On the basis of the complaint, we have set up a three-member inquiry committee," said Tamal Kanti Ghosh, the medical superintendent and vice-principal at SSKM Hospital.

After her death on Friday, the relatives went back to Ghosh with another written complaint and were promised that the authorities would find out the cause of death and take action against anyone found guilty.

Barnali, a homemaker and the mother of a 10-year-old boy, had been admitted to the "nephrology female ward" of the state's biggest referral hospital on January 28. She underwent an eight-hour kidney transplant operation on Tuesday, after which she was shifted to the "recovery cabin" in the nephrology ward. Family members said she was showing signs of recovery.

"Other patients in the ward heard her fall off the bed at 4am on Thursday. We were then sitting on the stairs outside the ward," said a relative.

"We were alerted by the screams of the other patients. Through the collapsible gate we could see the recovery cabin but the patient was not on the bed. The safety rails were not in place. We could also see the nurses jolt out of their sleep in their room and rush to the cabin to lift the patient back on the bed," the relative added.

"My wife had responded well to the operation and even spoken to us on Wednesday... but her condition deteriorated fast after the fall," added Anadi.

Doctors wanted to shift Barnali to the intensive care unit immediately as she was bleeding but could not do so because of unavailability of beds. Barnali was moved to the dialysis wing on the fourth floor at 9am on Thursday.

Around 6pm on Thursday, she was transferred to the critical care unit in the main block. She was declared dead around 3pm on Friday.

Medical superintendent Ghosh said he had advised Barnali's relatives to get an autopsy done as that would ascertain the cause of death. "But they did not opt for it."

The autopsy could have established whether the patient died because of injuries suffered in the fall less than 48 hours after the transplant or rejection of the transplanted kidney by her body or some other reason.

Experts, however, said rejection now happened only in 10 per cent of transplant cases.

"Most rejections are now reversible. In case a rejection is permanent, we put the patient back on dialysis and wait for another transplant. Only one per cent of transplant patients die because of the procedure," said a city-based nephrologist not associated with Barnali's treatment.