Standard Blood-Pressure Cuff May Help Prevent Contrast Nephropathy

July 24, 2012

By Gabriel Miller

NEW YORK (Reuters Health) Jul 23 - A cheap and readily available technique may help prevent contrast -induced acute kidney injury in high-risk patients, a pilot study suggests.

Ischemic preconditioning -- restricting and restoring blood flow to induce a protective effect against a subsequent insult -- is experimental at this point, but a German report online June 26 in Circulation shows that "remote" preconditioning may help protect high-risk kidneys during coronary angiography.

The intervention consisted of inflating a standard upper-arm blood-pressure cuff to 50mmHg above a patient's systolic blood pressure for five minutes and then deflating it for five minutes.

In the randomized study, 100 patients with impaired renal function received either the pretreatment (four cycles of alternating five-minute inflations and deflations) or a sham intervention that only inflated to 10mmHg above systolic blood pressure.

With kidney injury defined as an increase in serum creatinine of at least 25% or 0.5 mg/dL above baseline within 48 hours after angiography, 40% in the sham arm developed contrast nephropathy, vs 12% in the active arm.

No patient in the study had a major adverse event, the researchers say.

"The technique is safe, easy-to-perform and economic," lead author Dr. Fikret Er from the University of Cologne told Reuters Health by email. He said the surrogate endpoint used in the study "clearly suggests renal protection by ischemic preconditioning," but added that studies documenting morbidity and mortality are necessary, even though the procedure appears safe.

Dr. Derek Yellon, who directs the Hatter Cardiovascular Institute at University College London Hospital & Medical School and was not involved in the study, commented to Reuters Health that based on these results and earlier data, "there does not seem to be any drawbacks to this technique."

"There is no reason to see why such a technique cannot be used in higher risk patients," Dr. Yellon said in an email.

Still, he cautions, all of the research to date has been proof-of-concept and "this technique is not ready for widespread adoption yet."


Circulation 2012.