Effectiveness of Remote Ischemic Preconditioning for Prevention of Contrast Induced Acute Kidney Injury in Patients Undergoing Coronary Angiograms.

The use of imaging is increasing in clinical practice, either for diagnosis or intervention. In these imaging processes, contrast medium (CM) is widely used. However, CM administration can induce contrast-induced nephropathy (CI-AKI). CI-AKI is the third most common cause of renal insufficiency, and its incidence varies from 2% to 50% depending on patient risk factors; in addition, studies have shown that CI-AKI occurs in 2% to 25% of patients undergoing coronary intervention. CI-AKI is associated with significant mortality and morbidity in patients undergoing coronary angiography or other diagnostic contrast studies. We assessed the latest promising evidence on the ability of remote ischemic preconditioning (RIPC) to reduce the incidence of CI-AKI in patients undergoing Coronary Angiogram (CA) or diagnostic contrast studies such as CT angiogram, while at the same time being a non-invasive, low cost, easy, and safe method with absence of adverse effects. However, more randomized controlled trials are needed to confirm these preliminary results. The aim of this study is to minimize the incidence of CI-AKI at the University of Texas Medical Branch (UTMB). If found to be an effective method, RIPC would help minimize the incidence of CI-AKI in all institutions across the globe, who would adopt this intervention. The primary objective: i) reduce the rise in creatinine to \< 0.5 mg/dL post-CA in moderate to high risk patients and ii) reduce the incidence of renal replacement therapy post-CA in moderate to high risk patients; iii) we also aim to establish that RIPC is safe and effective. We hypothesize that the use of RIPC, when added to standard medical therapy (pre-and post-CA hydration), will mitigate the effects of contrast on the renal vasculature and lessen the incidence of CI-AKI in moderate to high risk patients at the University of Texas Medical Branch. The use of iodinated contrast to visually enhance target vasculature is a widely used diagnostic technique that is performed daily at UTMB, and around the world, for the diagnosis and management of a variety of conditions. A common complication of this procedure is acute kidney injury (AKI), generally referred to as contrast-induced nephropathy (CI-AKI). This complication can range from an isolated rise in serum creatinine to severe renal dysfunction necessitating renal replacement therapy. The incidence of CI-AKI has been reported as approximately 2-50%, depending upon the definition and sensitivity of assay employed to assess GFR in the hospital setting. In addition, CI-AKI is associated with significant mortality and morbidity. If proven to be beneficial, RIPC will bring about a reduction in incidence of CI-AKI, and thus help to reduce hospitalization and mortality from renal etiology following a given contrast procedure.