title: Early blood biomarkers predict organ injury and resource utilization following complex cardiac surgery.
abstract: BACKGROUND
  Patients undergoing complex cardiac surgery (thoracic aorta and valve) are at risk for organ failure and increased resource utilization. Neutrophil gelatinase-associated lipocalin (NGAL) has been found to be an early biomarker for renal injury. Multiplex cytokine immunoassays allow the evaluation of the early inflammatory response. We examined the relationship between early biomarker appearance (NGAL and multiplex cytokines) and organ injury and resource utilization.
  
  
  METHODS
  NGAL and multiplex cytokine immunoassays were performed at baseline, 1, 6, and 24 h following surgery on 38 patients undergoing thoracic aorta and valve operations. The mean age was 65 y with 26 males and 12 females. Acute kidney injury (AKIN definition), pulmonary failure (>24 h ventilation), and intensive care unit and hospital stays were examined.
  
  
  RESULTS
  One hour following complex cardiac surgery, the quartile of patients with the greatest IL-6 response had higher serum NGAL levels compared with the lowest quartile (347 versus 145 ng/mL, P=0.002), and 70% of these patients progressed to clinical kidney injury. Six hours following surgery, the quartile of patients with the greatest IL-10 response had higher serum NGAL compared with the lowest quartile (271 versus 160, P =0.04), more pulmonary failure (60% versus 10%, P =0.01), and longer ICU and hospital stays (P =0.001).
  
  
  CONCLUSIONS
  Patients with early elevated biomarkers of inflammation exhibited higher NGAL, more pulmonary failure, and greater resource utilization. Earlier identification of patients at risk for organ injury may allow for earlier intervention and reduce resource utilization.
authors.affiliation: Department of Surgery, Division of Thoracic and Cardiovascular Surgery, University of Florida College of Medicine, Gainesville, Florida 32610-0286, USA.
authors.forename: Tad
authors.initials: T
authors.lastname: Kim
authors.forename: George J
authors.initials: GJ
authors.lastname: Arnaoutakis
authors.forename: Azra
authors.initials: A
authors.lastname: Bihorac
authors.forename: Tomas D
authors.initials: TD
authors.lastname: Martin
authors.forename: Philip J
authors.initials: PJ
authors.lastname: Hess
authors.forename: Charles T
authors.initials: CT
authors.lastname: Klodell
authors.forename: Curtis G
authors.initials: CG
authors.lastname: Tribble
authors.forename: A Ahsan
authors.initials: AA
authors.lastname: Ejaz
authors.forename: Lyle L
authors.initials: LL
authors.lastname: Moldawer
authors.forename: Thomas Mark
authors.initials: TM
authors.lastname: Beaver
mesh_terms: D000209:Acute-Phase Proteins; D000368:Aged; D015415:Biomarkers / Q000097:blood; D006348:Cardiac Surgical Procedures; D016207:Cytokines / Q000097:blood*; D005260:Female; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D000071068:Lipocalin-2; D054834:Lipocalins / Q000097:blood*; D008297:Male; D011183:Postoperative Complications / Q000097:blood*; D011518:Proto-Oncogene Proteins / Q000097:blood*
chemical_list: D000209:Acute-Phase Proteins; D015415:Biomarkers; D016207:Cytokines; C489506:LCN2 protein, human; D000071068:Lipocalin-2; D054834:Lipocalins; D011518:Proto-Oncogene Proteins