12 May Dexamethasone May Limit Kidney Failure After Heart Surgery
MedicalResearch.com Interview with:
Kirolos A. Jacob, MD, MSc PhD Candidate
Division Vital Functions, Cardiothoracic Surgery and Intensive Care Medicine
University Medical Center Utrecht
Medical Research: What is the background for this study? What are the main findings?
Dr. Jacob: Heart surgery carries many risks for a patient undergoing such a procedure. One of the most devastating complications following open heart surgery is kidney failure requiring dialysis. Most of these patients who develop kidney failure requiring dialysis after surgery have some form of chronic kidney disease before the operation, which placed them at especially high risk. Approximately one out of every 100 patients undergoing open heart surgery develops severe kidney failure. When such kidney failure occurs, the patient has more than 40% chance of dying. 1% sounds like a small percentage, however given the fact that each year, over half a million people undergo heart surgery in the USA alone, this means that an estimated 5,000 patients develop renal failure and of those about 2,500 die as a result of this complication. This figure is rising yearly as more and more patients are being operated due to the aging population. Also, this elderly population has often significant pre-existing kidney disease, further increasing the incidence of kidney failure after a heart operation.
Thus, treatment strategies are needed for this relatively small yet very important and expanding group of patients. Heart surgery initiates an inflammatory reaction across the human body due to the surgical trauma and the heart-lung machine. This systemic immune system reaction is thought to play a vital role in the development of kidney injury after heart surgery.
Our study investigated the effects of dexamethasone, a strong anti-inflammatory drug, on severe kidney injury after heart surgery. Severe kidney injury was defined as the use of dialysis during the hospital stay after surgery. We discovered that patients who receive the drug used 56% less frequently kidney dialysis, when compared to those receiving a placebo. Thus patients who did not receive the drug had about 2.5x higher risk for developing kidney failure when compared to those receiving dexamethasone. The beneficial effects of dexamethasone were particularly present in those who already had pre-existing kidney disease before heart surgery. This reinforces the fact that this drug could be of major importance for the increasing elderly population with pre-existing kidney disease undergoing a heart operation.
Medical Research: What should clinicians and patients take away from your report?
Dr. Jacob: Patients undergoing heart surgery are of high risk of developing severe kidney failure, especially if they have underlying chronic kidney disease. Dexamethasone is an anti-inflammatory drug that may prevent against severe kidney failure after heart surgery. It is shown by our trial that especially those patients with previous chronic kidney disease benefit from dexamethasone.
Our study is the largest randomized, placebo-controlled trial showing a potential benefit of any therapeutic drug for the prevention of severe kidney injury following heart surgery. Dexamethasone is long-existing and very affordable drug. Such a single dose of the drug during a heart operation is also straightforward and painless for patients. Furthermore a single dose of the drug does not carry many important side-effects. All in all, these advantages make the intervention very accessible and cost-effective, especially since the costs for dialysis are very high.
Medical Research: What recommendations do you have for future research as a result of this study?
Dr. Jacob: The total number of dialysis events was relatively low despite the large sample size of our study. Furthermore, this was a post-hoc analysis of a trial, which means that the study did not originally set out to test the effect of dexamethasone on kidney failure requiring dialysis. Because of that, these very promising results need to be confirmed by other large trials.
Citation:
Intraoperative High-Dose Dexamethasone and Severe AKI after Cardiac Surgery
JASN ASN.2014080840; published ahead of print May 7, 2015, doi:10.1681/ASN.2014080840
MedicalResearch.com Interview with: Kirolos A. Jacob, MD, MSc PhD Candidate (2015). Dexamethasone May Prevent Kidney Failure After Heart Surgery
Last Updated on May 12, 2015 by Marie Benz MD FAAD