Two new born babies at a Sydney hospital were incorrectly administered nitrous oxide instead of oxygen.
This resulted into death of one newborn and another baby has suspected brain-damage.
Baby John Ghanem died shortly after being born on July 13 but his parents learnt the reason for his death only on Saturday.
The parents were told that their baby was mistakenly given nitrous oxide instead of oxygen.
Sonya Ghanem, the mother, was told that she needed a caesarean section and when she woke up from the sedatives, she was told by the hospital staff that her baby was dead.
"'Wake up', I would tell him, `wake up, wake up. What did they do to you'."
Mrs Ghanem says she left the hospital holding an empty baby capsule instead of her son.
"I came empty handed thinking I would hold my newborn, but no," she said.
Another baby born at the hospital in June was also mistakenly given nitrous oxide and remains in a critical condition.
Health experts fear that baby is likely to suffer long-term effects.
NSW Health Minister Jillian Skinner has apologised for the "devastating error" and announced a sweeping review of hospital theatres to ensure the fatal mix-up is not repeated.
Ms Skinner said she was "profoundly sorry" and the operating theatre in question had been corrected but remained closed.
"I deeply regret these families have suffered through such a devastating error," she said.
"NSW Health will do all it can to support them."
According to the Minister, the error was discovered last week when a paediatrician raised concerns following the death of one of the babies.
Hospital management is certain no other babies received gas from the affected outlet, she added.
Ms Skinner said the oxygen outlet was incorrectly installed by BOC Limited in July 2015 and the Government had contacted the company "demanding urgent advice" on how it occurred.
Initially it was thought that an oxygen machine was incorrectly installed and certified by gas supplier BOC Limited in July 2015.
An independent investigation chaired by an obstetrician will be conducted into Southwest Sydney Local Health District while BOC Limited will conduct its own inquiry.
