Ultrasound 'may stop kidney injury' from surgery

Blood flow problems in surgery can cause kidney injury

Ultrasound treatments could be used to prevent a common kidney complication than can arise after major surgery, researchers suggest.

The work, published in the Journal of the American Society of Nephrology, was carried out on mice.

But the researchers said there could be a "rapid translation" to human studies because the treatment for acute kidney injury (AKI) was simple and routine.

Experts said the study suggested potential for new therapies.

AKI is the sudden loss of kidney function, which can easily develop in any sick person through infection such as pneumonia, diarrhoea or a heart attack.

AKI can develop after major surgery, such as some kinds of heart surgery, because the kidneys can be deprived of normal blood flow during the procedure.

Once it has developed, there are few treatment options.

'Protection'

The University of Virginia team exposed anesthetised mice to ultrasound using a routine clinical imaging system 24 hours before disrupting the blood supply to the kidneys.

They then found the mice still had healthy kidneys after blood flow was restored.

But in other mice, who were given a "sham" ultrasound, the same disruption led to significant kidney injury.

The researchers suggest the ultrasound treatment stimulated an anti-inflammatory response from the spleen that then protected the kidneys.

Dr Mark Okusa, who led the study, said: "Our studies using non-invasive ultrasound now provide us with an active treatment that appears to be simple, effective, and nontoxic for the prevention of acute kidney injury.

"To our knowledge this has never been described for the prevention of tissue or organ injury.

"Interestingly, we suspect that similar mechanisms that lead to kidney injury may also lead to lung, heart, and liver damage and that this form of therapy might be effective for prevention of injury in other organs as well."

Prof Donal O'Donoghue, the former national clinical director for kidney care, who has called for action over the level of AKI, said the paper was interesting.

He added: "It suggests that there are protective strategies over and above good basic fluid and medicines management care that are the cornerstones of prevention.

"Studying the animal model further is the next step . But we also need to invest in AKI research in the UK."