Influence of volume therapy with a modern hydroxyethylstarch preparation on kidney function in cardiac surgery patients with compromised renal function: a comparison with human albumin.

Objective: There is continuing concern about the influence of hydroxyethylstarch on renal function in patients with compromised kidney function. Design: Prospective, randomized, single-center study. Setting: University-affiliated hospital. Patients: Fifty patients undergoing elective, first-time coronary artery bypass grafting using cardiopulmonary bypass with a preoperative serum creatinine between 1.5 and 2.5 mg/dL. Interventions: According to a prospective, randomized sequence, the patients received either hydroxyethylstarch with a low molecular weight (mean molecular weight 130 kD) and a low molar substitution (0.4) (6% hydroxyethylstarch 130/0.4) (n = 25) or 5% human albumin (n = 25). Volume was added to the priming (500 mL) and given perioperatively until the second postoperative day to keep pulmonary artery occlusion pressure or central venous pressure between 12 and 14 mm Hg. Measurements and Main Results: Serum creatinine and cystatin plasma levels were measured from arterial blood samples. From urine specimens, N-acetyl-β-D -glucosaminidase, glutathione transferase-a, and neutrophil gelatinase-associated lipocalin were measured. Measurements were performed after induction of anesthesia, at the end of surgery, 5 hrs after surgery, and on the first and second postoperative days. A follow-up after discharge from the hospital (60 days) was also done. Similar amounts of hydroxyethylstarch and albumin were infused. Serum creatinine, glomerular filtration rate, and cystatin C plasma levels were without significant differences between the groups. Concentrations of kidney-specific proteins were elevated at baseline and increased significantly after surgery without showing group differences. Urinary levels of neutrophil gelatinase-associated lipocalin increased more in the albumin- than in the hydroxyethylstarch-treated patients. None of the patients developed acute renal failure requiring renal replacement therapy during the hospital stay and thereafter. Conclusions: A hydroxyethylstarch preparation with a low molecular weight and a low molar substitution given in cardiac surgery patients with preoperative compromised kidney function did not negatively influence kidney integrity compared with a human albumin-based volume replacement strategy.