Lack of renoprotective effect of i.v. N-acetylcysteine in patients with chronic renal failure undergoing cardiac surgery.
BACKGROUND
Pre-existing chronic renal failure is a significant risk factor for acute renal failure (ARF) after cardiac surgery. N-acetylcysteine (NAC) has been shown to prevent contrast media-induced ARF. Our objective was to evaluate whether i.v. NAC has renoprotective effects in patients with mild renal failure undergoing cardiac surgery.


METHODS
In this prospective, randomized, double-blind study, 80 patients with mild to moderate renal failure undergoing elective heart surgery with cardiopulmonary bypass were recruited. All received either i.v. NAC (n=38) or placebo (n=39) at induction of anaesthesia and then up to 20 h. Urine N-acetyl-beta-D-glucosaminidase (NAG) and urine creatinine ratio, plasma creatinine, and serum cystatin C levels indicated renal function.


RESULTS
Levels of urinary NAG/creatinine ratio, plasma creatinine and serum cystatin C did not significantly differ between NAC and placebo groups during five postoperative days. Urine NAG/creatinine ratio increased over 30% in 100% of patients in the NAC group vs 92.3% in the placebo group (P=0.081). Plasma creatinine increased by 25% from baseline or over 44 mumol litre(-1) in 42.1% in NAC group vs 48.7% in placebo group (P=0.560). Serum cystatin C exceeded 1.4 mg litre(-1) in 78.9% in NAC group vs 61.5% in placebo group (P=0.096).


CONCLUSIONS
Prophylactic treatment with i.v. N-acetylcysteine had no renoprotective effect in patients with pre-existing renal failure undergoing cardiac surgery.
Ristikankare
A
A
Department of Anaesthesiology and Intensive Care Medicine, Helsinki University Central Hospital Helsinki, Finland. anne.ristikankare@hus.fi
Kuitunen
T
T
Kuitunen
A
A
Uotila
L
L
Vento
A
A
Suojaranta-Ylinen
R
R
Salmenperä
M
M
Pöyhiä
R
R
D000111:Acetylcysteine / Q000627:therapeutic use*; D000118:Acetylglucosaminidase / Q000652:urine; D058186:Acute Kidney Injury / Q000517:prevention & control*; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood / Q000652:urine; D006348:Cardiac Surgical Procedures; D002315:Cardiopulmonary Bypass; D003404:Creatinine / Q000097:blood / Q000652:urine; D055316:Cystatin C; D015891:Cystatins / Q000097:blood; D004311:Double-Blind Method; D005260:Female; D016166:Free Radical Scavengers / Q000627:therapeutic use; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications*; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000517:prevention & control*; D011229:Preanesthetic Medication; D011446:Prospective Studies; D017211:Treatment Failure; D014882:Water-Electrolyte Balance
D015415:Biomarkers; C525030:CST3 protein, human; D055316:Cystatin C; D015891:Cystatins; D016166:Free Radical Scavengers; D003404:Creatinine; D000118:Acetylglucosaminidase; D000111:Acetylcysteine