Kidney Failure; The faster fluid is removed using continuous dialysis from patients with failing kidneys, the higher the likelihood they will die in the next several months, according to a study publish today in JAMA Network Open by University of Pittsburgh School of Medicine researchers. Nearly two-thirds of critically ill patients with acute kidney injury have extra fluid accumulating in their bodies, which can put pressure on their lungs and cause injury to other organs.
Risk of kidney failure
They want to get this excess fluid out of our patients before it causes damage but; so in removing it, we’re actually causing a control loss of fluid that can sometimes cause stress on the heart and lead to dangerously low blood pressure,” said lead author Raghavan Murugan, M.D., M.S., associate professor in Pitt’s Department of Critical Care Medicine and UPMC physician.
So the question how rapidly to remove fluid? has ask in the critical care community for many years, but there’s been no good answer. Previous studies in outpatients who are not critically ill find that routine dialysis a procedure to remove waste, toxins, salt and extra water from the blood of people whose kidneys have fail when perform too quickly, is associate with increase risk of death.
Murugan partner with senior author Rinaldo Bellomo, M.D., Ph.D., a professor of intensive care medicine at the University of Melbourne in Australia to find out if that finding extends to critically ill patients. Their team examine data from 1,434 patients that Bellomo had previously collect for the Randomize Evaluation of Normal vs. Augment Level of Renal Replacement Therapy trial; which was conduct between December 30, 2005 and November 28, 2008 in 35 intensive care units in Australia and New Zealand.
Removing fluid slowly
The research team find that for every 0.5 milliliter increase in fluid; so remove per kilogram of the patient’s weight per hour (0.5 mL/kg/hr), their risk of death increases. That translates to a 51% to 66% higher risk of death in the next three months for critically ill patients; so for whom excess fluid is remove at a rate greater than 1.75 mL/kg/hr, compare to patients for whom excess fluid is remove at a rate less than 1.01 mL/kg/hr.
Murugan is quick to point out that his analysis shows association, not causation; until a clinical trial is perform to specifically test the effects of removing fluid faster versus slower; they cannot say for sure that removing fluid slowly is better for the patient. And, in some cases, such as imminent heart failure; hence Murugan says a more rapid removal of fluid might be warrant to prevent sudden death.
You have to balance the pros and the cons, and decide how fast to remove fluid base; so on your patient’s clinical condition, said Murugan; hence who also is a member of Pitt’s Clinical Research, Investigation, and Systems Modeling of Acute Illness Center and the Center for Critical Care Nephrology. But in a patient where I can’t find an immediate need to get fluid out quickly; they’ll be removing fluid at a slower rate until we get definitive results and guidance from a clinical trial.