Anest. intenziv. Med. 2008;19(6):297-303

Assessment of the reliability of the urinary neutrophil gelatinase-associated lipocalin (NGAL) as an early marker of renal dysfunction after cardiac surgery: A prospective observational studyAnaesthesiology - Original Paper

Gerlichová Monika^1,*, Černý Vladimír¹, Dostál Pavel¹, Živný Pavel²

¹ Klinika anesteziologie, resuscitace a intenzivní medicíny, Univerzita Karlova v Praze, LF v Hradci Králové a Fakultní nemocnice Hradec Králové

² Ústav klinické biochemie a diagnostiky, Univerzita Karlova v Praze, LF v Hradci Králové a Fakultní nemocnice Hradec Králové

Objective:
To assess the reliability of the urinary neutrophil gelatinase-associated lipocalin (NGAL) as an early marker of renal dysfunction after cardiac surgery.

Design:
A prospective observational study.
Setting:
Cardiac surgery ICU, University Hospital.

Materials and Methods:
We evaluated 65 patients who had had cardiac surgery with cardiopulmonary bypass. The exclusion criteria for enrolment in the study were pre-existing renal failure (serum creatinine above 350 μmol/l) requiring haemodialysis, and previous renal transplantation. Urine samples for NGAL analysis by ELISA were collected before incision and for 24 hours post-operatively. Postoperative acute kidney injury (AKI) was defined as 50% or greater increase in serum creatinine from the baseline or 25% or greater decrease in the glomerular filtration rate from the baseline. The statistical analysis was performed using Sigma Stat 3.1. software. The tests used to compare the variables included: The two-sample t-test, the Mann-Whitney rank sum test, the chi-square test and Fisher's exact test. A conventional ROC curve was generated to calculate the sensitivity and specificity for the urine NGAL measurement.

Results:
21 of 65 patients (32%) developed postoperative AKI. The urinary NGAL levels and kinetics were equivalent in patients with and without ARF.

Conclusion:
Urinary NGAL is not a reliable marker of renal dysfunction after adult cardiac surgery.

Keywords: acute kidney injury; cardiopulmonary bypass; markers of renal injury; neutrophil gelatinase-associated lipocalin; glomerular filtration; RIFLE criteria

Received: July 9, 2008; Accepted: September 21, 2008; Published: December 1, 2008  Show citation