Renal Protection for Coronary Angiography in Advanced Renal Failure Patients by Prophylactic Hemodialysis Presented by Mike Touchy, HO-I

Contrast and renal dysfunction Contrast nephropathy is 3 rd leading cause of hospital acquired AKI Pathogenesis not clear – toxic and ischemic injury to renal tubular cells (intrarenal vasoconstriction, medullary hypoxia, direct tubular cell death); length of exposure (lower the GFR = longer time period of excretion) serum Cr levels > 4.5 mg/dl - CN approaches 100% for diabetic patients and 60% for non-diabetic patients serum Cr levels > 4.5 mg/dl - CN approaches 100% for diabetic patients and 60% for non-diabetic patients

Prophylaxis to CIN and study hypothesis fluid supplements, low-osmolality contrast, a double dose of N-acetylcysteine – general population and mild CKD fluid supplements, low-osmolality contrast, a double dose of N-acetylcysteine – general population and mild CKD contrast media can be effectively removed from the blood of patients with chronic renal failure by hemodialysis Hypothesis – prophylactic hemodialysis would prevent CN in pts with advanced renal failure undergoing coronary procedures Hypothesis – prophylactic hemodialysis would prevent CN in pts with advanced renal failure undergoing coronary procedures

Study design and methods Prospective, RCT Participants – 8/2003 – 6/2006 Veterans General hospital in Taiwan inclusion criteria- older than 20 yo, referred for coronary angiography, and “stable” Cr >3.5 mg/dL (change of Cr 3.5 mg/dL (change of Cr <0.5mg/dL in past month) exclusion - contrast medium within the previous 7 days, treatment with metformin or NSAIDs drugs within the previous 48 h, newly diagnosed unstable diabetes, renal transplantation, and ESRD necessitating chronic dialysis.

Methods cont. Procedures – all participants given 1mL/kg/hr x 6 hrs before and 12 hrs after exposure to contrast (non-ionic iohexol)– then randomized to receive HD (experimental gr) or no dialysis (control gr) Procedures – all participants given 1mL/kg/hr x 6 hrs before and 12 hrs after exposure to contrast (non-ionic iohexol)– then randomized to receive HD (experimental gr) or no dialysis (control gr) Follow up – CrCl measured before and on 4 th day after angiography; additional Cr drawn if pt had incr in Cr > 25% from BL (AKI) every other day until dialysis started or renal function recovered and at discharge in all patients who did not need dialysis. Follow up – CrCl measured before and on 4 th day after angiography; additional Cr drawn if pt had incr in Cr > 25% from BL (AKI) every other day until dialysis started or renal function recovered and at discharge in all patients who did not need dialysis. Primary endpoint: change in CrCl between baseline and the fourth day; Secondary end points were the differences in Cr levels on the fourth day from baseline, peak Cr level during hospitalization, and Cr level at discharge between groups Primary endpoint: change in CrCl between baseline and the fourth day; Secondary end points were the differences in Cr levels on the fourth day from baseline, peak Cr level during hospitalization, and Cr level at discharge between groups

RESULTS 3,724 patients screened – 318 with CKD - Eighty-eight patients had ESRD patients had Cr 3.5mg/dl – 18 patients refused to enter the study - and 90 were enrolled and of these 42 were assigned to experimental gr and 40 to control group 3,724 patients screened – 318 with CKD - Eighty-eight patients had ESRD patients had Cr 3.5mg/dl – 18 patients refused to enter the study - and 90 were enrolled and of these 42 were assigned to experimental gr and 40 to control group 2 groups were similar with respect to demographic and baseline clinical characteristics. Among the patients in the dialysis group, dialysis was initiated at an interval of 81+/-32 min, ranging from 45 to 180 min, after exposure to the contrast medium 2 groups were similar with respect to demographic and baseline clinical characteristics. Among the patients in the dialysis group, dialysis was initiated at an interval of 81+/-32 min, ranging from 45 to 180 min, after exposure to the contrast medium

Discussion Patients with chronic renal failure are prone to atherosclerotic cardiovascular diseases, and renal dysfunction accounts for the greatest risk factor in developing CN after CAG. Patients with chronic renal failure are prone to atherosclerotic cardiovascular diseases, and renal dysfunction accounts for the greatest risk factor in developing CN after CAG. Once CN occurred, 36% to 60% of these high-risk patients required emergent dialysis, and the hospital stay was prolonged to an average of 17 days

Discussion Primary endpoint - change in CrCl between baseline and the fourth day: The baseline CrCl was similar in the dialysis (13.2 ml/min/1.73 m 2 ) and control (12.6 ml/min/1.73 m 2 ) groups; however, the CrCl on the fourth day after coronary angiography in the dialysis group was significantly higher than that in the control group Secondary end points - differences in Cr levels on the fourth day from baseline, peak Cr level during hospitalization, and Cr level at discharge between groups Significant differences between 2 groups in Cr levels on day 4 and peak; no significant difference in Cr levels at discharge between 2 groups

Discussion Length of hospital stay in dialysis vs control was 6 +/- 3 VS 13 +/- 18 (p = 0.017) Patients with kidney disease make up just 1% of the Medicare population, but account for nearly 10% of all Medicare costs. They average 1.8 hospitalizations per year, totaling 12 days. On average, renal patients stay 0.7 days longer and cost $7,975 more per hospital admission when compared to all Medicare patients The renal function of patients in the dialysis group was better preserved over the whole course after CAG compared with the control group. The renal function of patients in the dialysis group was better preserved over the whole course after CAG compared with the control group. Findings suggest that prophylactic hemodialysis in patients with advanced chronic renal failure undergoing coronary angiography reduces the intensity of acute renal deterioration due to contrast medium exposure, shortens hospital stay, and improves renal outcome. Findings suggest that prophylactic hemodialysis in patients with advanced chronic renal failure undergoing coronary angiography reduces the intensity of acute renal deterioration due to contrast medium exposure, shortens hospital stay, and improves renal outcome.