ROCHESTER, Minn., June 16 (UPI) -- U.S. scientists at the Mayo and Cleveland clinics say they've found blood flow interruption during kidney cancer surgery can lead to chronic kidney disease.
The researchers said their retrospective study found interrupting the blood flow for more than 20- to 25 minutes during kidney cancer surgery involving warm ischemia leads to a greater risk for patients developing chronic kidney disease.
The scientists analyzed outcomes of 362 patients with only one kidney who underwent renal cortical tumor surgery at either the Cleveland or Mayo clinics from 1990 to 2008. Using a technique called warm ischemia, surgeons kept the patient's kidneys at body temperature during the partial nephrectomy. Ischemia involves cutting off the blood supply to the kidney to control bleeding and keep blood from obscuring the surgeon's view.
Researchers said they found each additional minute of warm ischemia is associated with a 5 percent to 6 percent increase in the odds of developing acute renal failure and a 6 percent increased risk of new onset Stage IV chronic kidney disease during long-term follow-up.
"This is the largest evaluation of warm ischemia time in patients with a single kidney who are undergoing a partial nephrectomy," said Mayo Clinic urologist Dr. R. Houston Thompson, who led the study. "These results suggest every minute counts when the renal arteries and veins are clamped. When planning for the surgery, surgeons should make efforts to minimize ischemia time, especially in situations where a person only has one kidney."
The researchers stressed their results do not have implications for patients treated with cold ischemia.
The study appears in the journal European Urology.