June 7 (UPI) -- Removal of fluids from the body too quickly during kidney surgery can lead to early death, new findings show.
Kidney patients have up to a 66 percent higher risk of death three months after surgery when excess fluid is removed from the body at a rate higher than 1.75 milliliters, according to a study published Friday in JAMA Network Open.
"We want to get this excess fluid out of our patients before it causes damage but, in removing it, we're actually causing a controlled loss of fluid that can sometimes cause stress on the heart and lead to dangerously low blood pressure," Raghavan Murugan, associate professor in Pitt's Department of Critical Care Medicine and study lead author, said in a news release. "So the question -- how rapidly to remove fluid? -- has been asked in the critical care community for many years, but there's been no good answer."Acute kidney injuries cause excess fluid build-up in almost two-thirds of patients, according to the study. The fluid accumulation pushes against the lungs and causes damage to other organs. To relieve the problem, clinicians use dialysis to drain fluids from the blood stream, but oftentimes remove it too quickly. The study included more than 1,400 patients from a previous randomized trial evaluating renal replacement therapy between 2005 and 2008. The study showed the death risk rises for every 0.5 milliliter removed per kilogram of a person's body weight each hour.
The researchers caution that this analysis only shows a link between fluid removal and death risk, not a cause. Rapid removal is necessary in some cases, such as with life-threatening heart failure.
"You have to balance the pros and the cons, and decide how fast to remove fluid based on your patient's clinical condition," Murugan said. "But in a patient where I can't find an immediate need to get fluid out quickly, I'll be removing fluid at a slower rate until we get definitive results and guidance from a clinical trial."