Plasma neutrophil gelatinase-associated lipocalin and adverse outcome in critically ill patients with ventilatory support R. Linko 1 , V. Pettilä 1,2 , A. Kuitunen 1,3 , A. -M. Korhonen 1 , S. Nisula 1 , S. Alila 4 , O. Kiviniemi 5 , R. Laru-Sompa 6 , T. Varpula 1 , S. Karlsson 3 and the FINNALI Study Investigators* 1 Department of Anaesthesia and Intensive Care Medicine, Helsinki University Hospital, Helsinki, Finland, 2 Institute of Clinical Medicine, University of Helsinki, Helsinki, Finland, 3 Department of Intensive Care Medicine, Tampere University Hospital, Tampere, Finland, 4 Department of Anaesthesia and Intensive Care Medicine, Kymenlaakso Central Hospital, Kotka, Finland, 5 Department of Anaesthesia and Intensive Care Medicine, Lapland Central Hospital, Rovaniemi, Finland and 6 Department of Anaesthesia and Intensive Care Medicine, Central Hospital of Central Finland, Jyväskylä, Finland Objective: Plasma neutrophil gelatinase-associated lipocalin (pNGAL) has been introduced as an early and sensitive biomar- ker 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 het- erogeneous group of critically ill adult patients with acute respi- ratory 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 pre- dictive value of pNGAL for RRT, and hospital and 90-day mor- tality first separately, second in addition to the SimplifiedAcute Physiology Score (SAPS II), and third to RIFLE (Risk, Injury, Failure, Loss, End-Stage Renal Disease) AKI classification. Addi- tionally, 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% confi- dence 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 respira- tory failure. Accepted for publication 25 February 2013 © 2013 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd N eutrophil gelatinase-associated lipocalin (NGAL) is a sensitive biomarker for acute kidney injury (AKI) 1 in various clinical situations. 2–10 Elevated plasma NGAL (pNGAL) and urine NGAL (uNGAL) even without increase in serum creatinine have been suggested to detect patients with subclini- cal AKI and patients with an increased risk for renal replacement therapy (RRT), prolonged stay in the intensive care unit (ICU), and adverse outcome. 11 However, the independent predictive outcome findings are predominantly limited to studies in paediatric and adult patients with cardiac surgery and cardiorenal syndrome. 11 Few studies have focused on critically ill patients outside cardiac surgery. 7–10,12,13 So far, no NGAL study has evaluated a more representative group of critically ill adult patients with acute respiratory failure, 14 the most common organ dysfunction. Acute respiratory failure affects 39–63% of criti- cally ill patients. 15–17 Various clinical disorders and risk factors can predispose and lead to acute respi- ratory failure, and concomitant organ failures, including AKI, are frequent. 15,18 Furthermore, acute respiratory failure is an individual risk factor for the evolution of AKI. 19 Coexisting non-pulmonary organ dysfunction increases the mortality of Acta Anaesthesiol Scand 2013; 57: 855–862 Printed in Singapore. All rights reserved © 2013 The Acta Anaesthesiologica Scandinavica Foundation. Published by John Wiley & Sons Ltd ACTA ANAESTHESIOLOGICA SCANDINAVICA doi: 10.1111/aas.12112 855