title: AKI in low-risk versus high-risk patients in intensive care.
abstract: OBJECTIVE
  AKI in critically ill patients is usually part of multiorgan failure. However, nonrenal organ failure may not always precede AKI and patients without evidence of these organ failures may not be at low risk for AKI. This study examined the risk and outcomes associated with AKI in critically ill patients with and without cardiovascular or respiratory organ failures at presentation to the intensive care unit (ICU).
  
  
  METHODS
  A large, academic medical center database, with records from July 2000 through October 2008, was used and the authors identified a low-risk cohort as patients without cardiovascular and respiratory organ failures defined as not receiving vasopressor support or mechanical ventilation within the first 24 hours of ICU admission. AKI was defined using Kidney Disease Improving Global Outcomes criteria. The primary end points were moderate to severe AKI (stages 2-3) and risk-adjusted hospital mortality.
  
  
  RESULTS
  Of 40,152 critically ill patients, 44.9% received neither vasopressors nor mechanical ventilation on ICU day 1. Stages 2-3 AKI occurred less frequently in the low-risk patients versus high-risk patients within 24 hours (14.3% versus 29.1%) and within 1 week (25.7% versus 51.7%) of ICU admission. Patients developing AKI in both risk groups had higher risk of death before hospital discharge. However, the adjusted odds of hospital mortality were greater (odds ratio, 2.99; 95% confidence interval, 2.62 to 3.41) when AKI occurred in low-risk patients compared with those with respiratory or cardiovascular failures (odds ratio, 1.19; 95% confidence interval, 1.09 to 1.3); interaction P<0.001.
  
  
  CONCLUSIONS
  Patients admitted to ICU without respiratory or cardiovascular failure have a substantial likelihood of developing AKI. Although survival for low-risk patients is better than for high-risk patients, the relative increase in mortality associated with AKI is actually greater for low-risk patients. Strategies aimed at preventing AKI should not exclude ICU patients without cardiovascular or respiratory organ failures.
authors.affiliation: Center for Critical Care Nephrology and Clinical Research, Investigation, and Systems Modeling of Acute Illness Center, Departments of Critical Care Medicine and Department of Biostatistics, University of Pittsburgh Graduate School of Public Health, Pittsburgh, Pennsylvania; and.
authors.forename: Florentina E
authors.initials: FE
authors.lastname: Sileanu
authors.affiliation: Center for Critical Care Nephrology and Clinical Research, Investigation, and Systems Modeling of Acute Illness Center, Departments of Critical Care Medicine and.
authors.forename: Raghavan
authors.initials: R
authors.lastname: Murugan
authors.affiliation: Center for Critical Care Nephrology and Clinical Research, Investigation, and Systems Modeling of Acute Illness Center, Departments of Critical Care Medicine and.
authors.forename: Nicole
authors.initials: N
authors.lastname: Lucko
authors.affiliation: Clinical Research, Investigation, and Systems Modeling of Acute Illness Center, Departments of Critical Care Medicine and.
authors.forename: Gilles
authors.initials: G
authors.lastname: Clermont
authors.affiliation: Center for Critical Care Nephrology and Department of Pharmacy and Therapeutics, University of Pittsburgh School of Pharmacy, Pittsburgh, Pennsylvania.
authors.forename: Sandra L
authors.initials: SL
authors.lastname: Kane-Gill
authors.affiliation: Center for Critical Care Nephrology and Biomedical Informatics, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania;
authors.forename: Steven M
authors.initials: SM
authors.lastname: Handler
authors.affiliation: Center for Critical Care Nephrology and Clinical Research, Investigation, and Systems Modeling of Acute Illness Center, Departments of Critical Care Medicine and kellumja@upmc.edu.
authors.forename: John A
authors.initials: JA
authors.lastname: Kellum
mesh_terms: D000046:Academic Medical Centers; D058186:Acute Kidney Injury / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000628:therapy; D000293:Adolescent; D000328:Adult; D000368:Aged; D016638:Critical Illness; D016208:Databases, Factual; D005260:Female; D017052:Hospital Mortality; D006801:Humans; D007362:Intensive Care Units; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009102:Multiple Organ Failure / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000628:therapy; D015999:Multivariate Analysis; D016017:Odds Ratio; D011379:Prognosis; D016016:Proportional Hazards Models; D018570:Risk Assessment; D012307:Risk Factors; D013997:Time Factors; D055815:Young Adult
keywords: kidney disease; mortality; outcomes