Prophylactic Dialysis Renoprotective
In patients with advanced renal failure, it preserves kidney function following coronary angiography.
Prophylactic hemodialysis following coronary angiography improves renal outcomes in patients with advanced renal failure, researchers conclude.
Based on their findings, they strongly suggest this approach in patients with a creatinine clearance below 25 mL/min per 1.73 m2, according to a report in the Journal of the American College of Cardiology (2007;50:1015-1020).
Contrast media, excreted mainly by glomerular filtration, are eliminated slowly in patients with chronic renal failure, thus exposing these patients to contrast media longer. They cited previous research showing that when serum creatinine levels are above 4.5 mg/dL, the likelihood of contrast nephropathy approaches 100% for diabetics and 60% for non-diabetics.
The study included 82 patients with chronic renal failure (creatinine levels above 3.5 mg/dL) who were referred for coronary angiography. The study excluded patients with end-stage renal disease necessitating chronic dialysis.
Researchers randomly assigned 42 patients to receive either IV normal saline intravenously and prophylactic hemodialysis and 40 patients to receive IV normal saline only (controls). The two groups had similar clinical characteristics. Fifty-five percent of the hemodialysis group and 62% of the control group had diabetes.
Hemodialysis was started as soon as technically possible following angiography. Investigators recorded the time from contrast exposure to the initiation of hemodialysis. The hemodialysis group had a significantly smaller decrease in mean creatinine clearance within 72 hours than controls (0.4 vs. 2.2 mL/min per 1.73 m2).
In addition, at day 4 after the procedure, mean serum creatinine concentrations were significantly higher in controls than in the hemodialysis-treated patients (6.3 vs. 51 mg/dL). Thirty-five percent of control patients required temporary renal replacement therapy compared with 2% of the hemodialysis group. After hospital discharge, none of the patients in the hemodialysis group required long-term dialysis compared with 13 control patients.
The mean volume of contrast medium administered was 106.8 mL and 109.1 mL in the hemodialysis and control groups, respectively.
The researchers pointed out that the “overwhelming positive effect of our study may be due to the high-risk population we chose.” All patients had a residual creatinine clearance less than 25 mL/min per 1.73 m2, making their kidneys vulnerable to further injury. “Thus, the rapid removal of nephrotoxic contrast agents by hemodialysis was dramatically shown to be of great benefit,” the investigators reported.