By Paul Mayne
A simple step developed by a Western researcher may alleviate the potential damage to multiple organs often associated with dialysis, an important treatment for countless patients with kidney disease.
Schulich School of Medicine & Dentistry Professor Chris McIntyre, who arrived from the University of Nottingham last month, said kidney disease patients are caught between a rock and a hard place – they cannot live with or without dialysis.
“Patients die a lot. Your chances of dying on dialysis are about the same as with every single kind of cancer,” said McIntyre, the Robert Lindsay Chair of Dialysis Research and Innovation. “Those who do survive suffer substantial injury that appears to be related to the treatment. It can damage their hearts and other organs, but we’re now starting to appreciate they’re damaging their brain as well.”
Prior to coming to Western, McIntyre and his colleagues studied 73 patients on hemodialysis (where blood is filtered through a machine) where the dialysate was cooled and followed up with them for a year. The findings, published in the Journal of the American Society of Nephrology, showed patients exhibited complete protection against white matter changes in the brain.
“We’ve done a lot of work relating to how the blood pressure, being unstable when you take the fluid off on dialysis, drives that injury,” McIntyre said of patients who normally face a severe drop in blood pressure due to the sudden removal of bodily fluids. “We looked around for techniques that were already established in dialysis to improve the blood pressure and stop these drops, and cooling has been used since the late 1980s.
“So, we applied a technique already available and wanted to see whether or not we’re not just making people feel better, but we can actually get organ protection.”
The technique involves cooling the dialysate temperature to either 37 degrees C, or .5 degrees C below the core body temperature. By doing so, patients were completely protected against blood pressure changes.
While an established technique, it was how McIntyre applied the method that made the difference.
“Before it was being used reactively for those who were having trouble with blood pressure, not from the get go,” said McIntyre, director of London Kidney Clinical Research Unit at London Health Sciences Centre. “And the big problem about cooling the dialysate is people feel cold. What we did, which hasn’t been done before, was we individualized the temperature to each patient’s temperature, that way we got the benefits, but they didn’t feel cold.”
While he had conducted other studies that had showed they could reduce the short-term injury, what he didn’t know is whether or not, by reducing all those cumulative short-term injuries, you really could protect other organs.
“What was surprising, I think, was the scale of the response, that we actually managed to entirely remove this very sophisticated and sensitive measure of brain injury; we had complete resolution,” said McIntrye, who will also work withmedical imaging at the Robarts Research Institute.
Even better than the findings itself, McIntyre added, is the fact this cooling intervention is simple to perform and can be delivered without any additional cost.
“It’s universally applicable,” he said. “Dialysis is an industrialized process. If we’re going to make it better, any intervention we develop that’s not in the same keeping is probably not going to be transformational.”