The jacket that gives kidney failure patients dialysis on the go

The jacket that gives kidney failure patients dialysis on the go

By Pat Hagan
Last updated at 12:34 AM on 02nd September 2008

A jacket that carries out 'dialysis on the go' could be a major advance for those with kidney failure.

The jacket contains a miniature version of the bulky hospital equipment normally needed to do the job of diseased kidneys.

It means patients who would spend hours hooked up to dialysis machines can instead carry on with normal daily life or even go on an aeroplane.

The scientists developing the dialysis jacket hope to have it commercially available within the next three years.

Researchers have been trying since the mid-Eighties to find a way of compressing dialysis equipment into a portable or wearable form.

But they have been hampered by the need for it to process large amounts of fluid needed to flush out toxins from the blood.

Now experts think they have found a way round this problem, using much smaller amounts of fluid that can be recycled within the device.

The kidneys play a vital role in filtering waste products from the blood and regulating blood flow.

They contain millions of filters called nephrons, which remove excess fluid and waste from the blood. This gets expelled from the body when we urinate.

But when nephrons are damaged, the filtering system malfunctions and dangerous levels of fluid and waste products can accumulate.

Around four in every 1,000 people in Britain will develop kidney disease and the number of cases of chronic kidney failure is on the increase in the UK.

Some will respond to drugs, but a small minority end up with end-stage renal failure. These patients must attend hospital two to three times a week to be hooked up to a dialysis machine to remove toxins from the body.

There are two main dialysis techniques deployed by doctors. Around 25 per cent of kidney failure patients in Britain undergo peritoneal dialysis.

This involves a sterile mixture of sugar and minerals being pumped through a tube in the abdomen into an area called the peritoneal cavity - the membrane that lines the abdominal cavity.

As the liquid circulates, it sucks out waste products and chemicals from the blood vessels. These are then pumped out and disposed of.

However, existing equipment needs around eight litres of this solution to perform one dialysis session, which can last up to five hours.

Haemodialysis involves removing blood from the body, filtering it and pumping it back in.

The new jacket, called the Automated Wearable Artificial Kidney, uses peritoneal dialysis, but needs just one litre of liquid.

The patient has a catheter fitted in their stomach. When they put on the AWAK jacket, they attach this catheter to a tube through which the fluid is pumped.

Once the fluid returns to the jacket, the waste products are filtered out. The fluid is then resupplied with minerals needed to filter the blood and pumped back into the body.

Each litre of fluid could be recycled for up to six months before it needs changing.

Dr Kevin Harris, consultant nephrologist at Leicester General Hospital, says that if the jacket works it could significantly improve quality of life for patients.

'The Holy Grail of dialysis is to reduce the size and complexity of the kit involved. That would make it far more convenient for patients.

'With peritoneal dialysis, you need at least eight litres of fluid and sometimes more. If this device reduces that to just one litre that can be recycled, it would be an advantage.'

http://www.dailymail.co.uk/health/article-1051549/The-jacket-gives-kidney-failure-patients-dialysis-go.html