For patients with kidney failure who need dialysis, removing fluid at the correct rate and stopping at the right time is critical. This typically requires guessing how much water to remove and carefully monitoring the patient for sudden drops in blood pressure.
Currently there is no reliable, easy way to measure hydration levels in these patients, who number around half a million in the United States. However, researchers from MIT and Massachusetts General Hospital have now developed a portable sensor that can accurately measure patients’ hydration levels using a technique known as nuclear magnetic resonance (NMR) relaxometry.
“There’s a tremendous need across many different patient populations to know whether they have too much water or too little water,” says Cima, who is the senior author of the study and a member of MIT’s Koch Institute for Integrative Cancer Research. “This is a way we could measure directly, in every patient, how close they are to a normal hydration state.”
The MIT team decided to try a different approach, based on NMR. Cima had previously launched a company called T2 Biosystems that uses small NMR devices to diagnose bacterial infections by analyzing patient blood samples. One day, he had the idea to use the devices to try to measure water content in tissue, and a few years ago, the researchers got a grant from the MIT-MGH Strategic Partnership to do a small clinical trial for monitoring hydration. They studied both healthy controls and patients with end-stage renal disease who regularly underwent dialysis.
“The water retention issues of congestive heart failure patients are very significant,” Cima says. “Our sensor may offer the possibility of a direct measure of how close they are to a normal fluid state. This is important because identifying fluid accumulation early has been shown to reduce hospitalization, but right now there are no ways to quantify low-level fluid accumulation in the body. Our technology could potentially be used at home as a way for the care team to get that early warning.”
This is a great example of the dangers of OVER hydration, something that is not as commonly talked about. It is common to be slightly dehydrated due to forgetfulness or busyness. This article outlines the danger of overhydration not only for patients of kidney disease (where it is deadly) but of all people as well. MIT developed a portable sensor to monitor hydration levels to ensure safety for dialysis patients. There’s no discussion of it being wearable or the size of the device as it is mostly used during dialysis and therefore can stay in a home or at a hospital. But there is plenty of important information regarding the necessity for devices such as these to be accurate as the stakes are much higher than standard underhydration.