The NSW opposition has pointed the finger at the government following reports children are being put at risk because of a lack of pediatric heart transplants at The Children's Hospital at Westmead.

The hospital completed five of the transplants in 2021 when COVID-19 travel restrictions were enforced, but has reverted to transferring patients to Melbourne's Royal Children's Hospital, Nine reported on Sunday.

The Melbourne hospital is home to Australia's National Paediatric Heart Transplant Centre.

Between one and three children have died each year over the past five years in NSW because they were either too sick to be transferred to Melbourne or it was impractical for their families to go interstate, Nine reported.

NSW opposition health spokesman Ryan Park blamed the absence of the transplants in Sydney on a lack of funding by the Liberal National government, along with a staffing crisis and a "long overdue review" that began in 2021.

"These reports are obviously very concerning. Children's lives are being placed at risk and this is not acceptable," Mr Park said.

"At the end of 2021, a review into the Nationally Funded Centre was started and to date it still isn't finished. The government has failed to ensure that this review was completed and recommendations implemented. Meanwhile lives are being lost.

"The NSW health system cannot cope with another four years of Band-Aid solutions."

The Royal Children's Hospital's pediatric heart transplantation service is part of the Nationally Funded Centres program, which is funded by a pool with contributions from all states and territories.

Two weeks out from the NSW election, Mr Park reiterated Labor's plan for a "fresh start" for the state's health system and hospitals.

The plan included "safe staffing levels" in hospitals, returning 600 beds to Western Sydney, and upgrades to hospitals at Canterbury, Fairfield, Mount Druitt and Blacktown.

The Sydney Children's Hospitals Network referred questions to NSW Health, which has been contacted for comment.

Access to highly specialised clinical services such as pediatrics heart transplants was determined at a national level and was a matter for the commonwealth, a Royal Children's Hospital spokeswoman said.