Preventing Kidney Damage After Imaging Procedures: Contrast Dye

[okarol]

Preventing Kidney Damage After Imaging Procedures: How To Minimize Dangers Of Contrast Dye

Date:     December 11, 2006
www.sciencedaily.com

The Society for Cardiovascular Angiography and Interventions (SCAI) has released recommendations for the prevention of contrast induced nephropathy (CIN) -- potentially fatal kidney damage that can occur when a special dye is injected during certain cardiovascular procedures. The consensus document, the first to be written on this topic, appears in the January 2007 issue of Catheterization and Cardiovascular Interventions: Journal of the Society for Cardiovascular Angiography and Interventions.

Contrast dye is essential for many diagnostic and interventional cardiovascular procedures because it enables doctors to visualize blocked blood vessels, said Dr. Marc J. Schweiger, lead author of the SCAI consensus document. "As interventionalists, we work with contrast media every day, so it is crucial that we know how to avoid CIN, with its associated morbidity and mortality."

Dr. Schweiger stressed that CIN is relatively rare; the condition is estimated to occur in 1--3 percent of individuals who undergo interventional cardiovascular procedures in which contrast dyes are used. Patients at greatest risk are the elderly, and those with diabetes, chronic kidney disease, or advanced heart failure. "Nevertheless, we feel that 3 percent is too high a rate, and a lot can be done to lower the risk," Dr. Schweiger said.

In developing the consensus statement, members of SCAI's Catheterization Laboratory Performance Standards Committee (chaired by Dr. Charles E. Chambers) reviewed all of the published literature addressing ways to minimize the risk of CIN. Among the Society's key recommendations are the following:

   1. Do the right tests to properly assess a patient's kidney function. -- In most cases, physicians can get an accurate measure of how well a patient's kidneys are working by estimating the glomerular filtration rate, or eGFR. This test is superior to the often-used serum creatinine test.
   2. Make sure patients are adequately hydrated before, during, and after the procedure. -- "Hydration is very important in preventing CIN," Dr. Schweiger said. "High-risk patients should come for their procedure in plenty of time to be properly hydrated using intravenous hydration."
   3. Address with patients whether to discontinue the use of non-steroidal anti-inflammatory (NSAID) agents 24--48 hours before a procedure. -- Medications such as ibuprofen and Naprosyn are known as NSAIDs and are usually taken for aches and pains associated with arthritis, headache, back injury, and other ailments. These medications can potentially cause a kidney problem by decreasing blood flow to the kidneys. Because contrast dyes can also decrease kidney blood flow, the two agents should not be given concurrently.
   4. In patients at increased risk for CIN, use contrast agents with lower osmolarity, and in the smallest possible quantities. -- Contrast agents with lower osmolarity are less dense and, therefore, less likely to interfere with blood flow to the kidneys.
   5. Monitor patients at increased risk for CIN very closely for up to 48 hours after a procedure that involved the use of contrast dye. -- Physicians and nurses should be on the lookout for any signs of kidney failure. During this period, the serum creatinine test is useful for monitoring kidney function. In addition, patients should not resume taking NSAIDs until their kidney function has returned to normal.

CIN is a rare complication and, in most cases, is preventable, Dr. Schweiger stressed. "We certainly do not want to discourage people from having a procedure they really need because of fears of a complication that is unlikely to occur. The benefits of undergoing most diagnostic and interventional procedures far outweigh any risks associated with the use of contrast dye in such procedures," he said. "In fact, contrast dyes have helped us make enormous progress in the treatment of patients with blocked arteries."

About SCAI

Headquartered in Washington, DC, the Society for Cardiovascular Angiography and Interventions is a 3,700-member professional organization representing invasive and interventional cardiologists. SCAI's mission is to promote excellence in invasive and interventional cardiovascular medicine through physician education and representation, and advancement of quality standards to enhance patient care. SCAI was organized in 1976 under the guidance of Drs. F. Mason Sones and Melvin P. Judkins. The first SCAI Annual Scientific Sessions were held in Chicago in 1978.

original: http://www.sciencedaily.com/releases/2006/12/061211124125.htm

[nextnoel]

Very interesting post, okarol.  In July I had a stress test because of some mild cardiac symptoms, which turned up some slightly odd results.  The cardiologist wanted to pursue with a "calcium channel test" instead of the more frequently used test that involved contrast dye injection.  My nephrologist agreed strongly that I should definitely not have contrast dye.  My insurance company (MAMSI) denied permission for the test, saying it was still "experimental".  My cardiologist and nephrologist submitted to the review committee very precise letters explaining the risk of losing my remaining kidney function if a contrast dye were used.  MAMSI still refused to OK the calcium channel test.  They did, however, assure me that if I lost my remaining kidney function due to the contrast dye, they would happily pay for dialysis or a transplant, if necessary, so not to worry!  (Can you spell "STOOPID"? )

In October, I had the opportunity to switch to Kaiser Permanente, and my first appointment will be after Christmas.  Needless to say, I'm hoping for a more positive approach from them!

[Whamo]

I had this test, and shortly afterwards, my kidney failed.  It's a horrible test.  It makes you shake for a few minutes as it speeds up the heart.  An elderly woman on deck for the same procedure refused to take the test after watching me go through it.  When I was up for a transplant they wanted to repeat the test, as a treadmill test couldn't get my heart rate up enough.  I dropped out of the transplant program at that point.  I have conjestive heart failure and chronic Hep C, so I wouldn't be a good candidate for a transplant anyway at age 61.