Plasma neutrophil gelatinase-associated lipocalin and adverse outcome in critically ill patients with ventilatory support

Abstract

Objective: Plasma neutrophil gelatinase-associated lipocalin (pNGAL) has been introduced as an early and sensitive biomarker of acute kidney injury (AKI), with an increased risk for renal replacement therapy (RRT) and adverse outcome in selected critically ill patient groups. Acute respiratory failure is the most common organ dysfunction in critically ill patients with an increased risk for AKI. Accordingly, we hypothesized that pNGAL would independently predict adverse outcome in a heterogeneous group of critically ill adult patients with acute respiratory failure.

Design and setting: Prospective, multi-centre study in 25 Finnish intensive care units.

Patients and methods: pNGAL was measured from critically ill patients with acute respiratory failure. We evaluated the predictive value of pNGAL for RRT, and hospital and 90-day mortality first separately, second in addition to the Simplified Acute Physiology Score (SAPS II), and third to RIFLE (Risk, Injury, Failure, Loss, End-Stage Renal Disease) AKI classification. Additionally, we assessed the factors associated with pNGAL by linear regression analysis.

Interventions: None.

Measurements and main results: We included 369 patients. Median (interquartile range) baseline pNGAL was 169 (92-370) ng/ml. The areas under receiver operating characteristic curves of baseline pNGAL were as follows: 0.733 [95% confidence interval (CI) 0.656-0.810] for RRT, 0.627 (95% CI 0.561-0.693) for hospital, and 0.582 (95% CI 0.520-0.645) for 90-day mortality. Present infection, baseline creatinine, operative status, and pancreatitis were independently associated with baseline pNGAL.

Conclusions: Baseline pNGAL gives no additional value into prediction of hospital and 90-day mortality compared with RIFLE or SAPS II, and has only moderate predictive power regarding RRT in critically ill adult patients with acute respiratory failure.