Around 20,000 Australians have bypass-assisted surgery each year
Australian researchers have identified a likely reason many patients develop kidney problems during heart-lung bypass surgery, with pre-existing heart failure cutting kidney blood flow by 55% in a large animal study.
Professor Yugeesh Lankadeva and his team at the University of Melbourne’s Florey Institute of Neuroscience and Mental Health led the work, which was published in the week of 28 September 2026 in the journal Anaesthesia.
More than 40% of patients who undergo surgery with a heart-lung machine develop sudden kidney failure. That complication increases the risk of dying in hospital and of chronic kidney disease, including end stage renal disease.
About 20,000 people in Australia undergo operations using a heart-lung bypass machine each year, including open heart surgery. Globally, the number is as high as 2 million.
The researchers found oxygen levels deep within the kidneys stayed almost two-thirds lower in the heart failure group than in the healthy comparison group 48 hours after surgery.
Lankadeva said even mild kidney injury after heart surgery can increase the risk of chronic kidney disease or lead to death. He said the findings could play a significant role in preventing this type of injury in the future.
Clinical trials of sodium ascorbate planned
The team will next move to clinical trials of a new formulation of sodium ascorbate. Doctors would give it directly into the bloodstream from the onset of surgery to prevent sudden kidney failure.
Lankadeva hopes the drug will improve health outcomes for patients who currently have no effective interventions.
Heart Foundation chief scientific and medical officer Professor Derek Chew said the findings would help address a significant challenge in cardiopulmonary bypass. He said the discovery could pave the way to a new therapy that helps millions of people worldwide.
The initial study into the cause of kidney failure was backed by a Heart Foundation Vanguard Grant and a Future Leader Fellowship. In 2025, the wider five-year research program received a $4.9 million Cardiovascular Health Mission Medical Research Future Fund grant.
The research was highlighted on World Heart Day 2026 as the team prepared for the next stage of testing. A start date for the clinical trials was not given.
