title: A randomized controlled trial on the effects of goal-directed therapy on the inflammatory response open abdominal aortic aneurysm repair.
abstract: BACKGROUND
  Goal-directed therapy (GDT) has been shown in numerous studies to decrease perioperative morbidity and mortality. The mechanism of benefit of GDT, however, has not been clearly elucidated. Targeted resuscitation of the vascular endothelium with GDT might alter the postoperative inflammatory response and be responsible for the decreased complications with this therapy.
  
  
  METHODS
  This trial was registered at ClinicalTrials.gov as NCT01681251. Forty patients undergoing elective open repair of their abdominal aortic aneurysm, 18 years of age and older, were randomized to an interventional arm with GDT targeting stroke volume variation with an arterial pulse contour cardiac output monitor, or control, where fluid therapy was administered at the discretion of the attending anesthesiologist. We measured levels of several inflammatory cytokines (C-reactive protein, Pentraxin 3, suppressor of tumorgenicity--2, interleukin-1 receptor antagonist, and tumor necrosis factor receptor-III) preoperatively and at several postoperative time points to determine if there was a difference in inflammatory response. We also assessed each group for a composite of postoperative complications.
  
  
  RESULTS
  Twenty patients were randomized to GDT and twenty were randomized to control. Length of stay was not different between groups. Intervention patients received less crystalloid and more colloid. At the end of the study, intervention patients had a higher cardiac index (3.4 ± 0.5 vs. 2.5 ± 0.7 l/minute per m(2), p < 0.01) and stroke volume index (50.1 ± 7.4 vs. 38.1 ± 9.8 ml/m(2), p < 0.01) than controls. There were significantly fewer complications in the intervention than control group (28 vs. 12, p = 0.02). The length of hospital and ICU stay did not differ between groups. There was no difference in the levels of inflammatory cytokines between groups.
  
  
  CONCLUSIONS
  Despite being associated with fewer complications and improved hemodynamics, there was no difference in the inflammatory response of patients treated with GDT. This suggests that the clinical benefit of GDT occurs in spite of a similar inflammatory burden. Further work needs to be performed to delineate the mechanism of benefit of GDT.
  
  
  BACKGROUND
  ClinicalTrials.gov Identifier: NCT01681251 . Registered 18 May 2011.
authors.affiliation: Department of Anesthesia, University of Manitoba, 2nd Floor Harry Medovy House, 671 William Avenue, R3E 0Z2, Winnipeg, MB, Canada. funk@cc.umanitoba.ca.
authors.forename: Duane J
authors.initials: DJ
authors.lastname: Funk
authors.affiliation: Department of Anesthesia, University of Manitoba, 2nd Floor Harry Medovy House, 671 William Avenue, R3E 0Z2, Winnipeg, MB, Canada. Kent.HayGlass@med.umanitoba.ca.
authors.forename: Kent T
authors.initials: KT
authors.lastname: HayGlass
authors.affiliation: Department of Anesthesia, University of Manitoba, 2nd Floor Harry Medovy House, 671 William Avenue, R3E 0Z2, Winnipeg, MB, Canada. jkoulack@hsc.mb.ca.
authors.forename: Joshua
authors.initials: J
authors.lastname: Koulack
authors.affiliation: Department of Anesthesia, University of Manitoba, 2nd Floor Harry Medovy House, 671 William Avenue, R3E 0Z2, Winnipeg, MB, Canada. gharding2@hsc.mb.ca.
authors.forename: Greg
authors.initials: G
authors.lastname: Harding
authors.affiliation: Department of Anesthesia, University of Manitoba, 2nd Floor Harry Medovy House, 671 William Avenue, R3E 0Z2, Winnipeg, MB, Canada. aboyd2@hsc.mb.ca.
authors.forename: April
authors.initials: A
authors.lastname: Boyd
authors.affiliation: Department of Anesthesia, University of Manitoba, 2nd Floor Harry Medovy House, 671 William Avenue, R3E 0Z2, Winnipeg, MB, Canada. elbrinky@gmail.com.
authors.forename: Ryan
authors.initials: R
authors.lastname: Brinkman
mesh_terms: D000368:Aged; D017544:Aortic Aneurysm, Abdominal / Q000601:surgery*; D015415:Biomarkers / Q000097:blood; D001794:Blood Pressure; D002097:C-Reactive Protein / Q000032:analysis; D002302:Cardiac Output; D002630:Chemotactic Factors / Q000097:blood; D000077324:Crystalloid Solutions; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006801:Humans; D053590:Interleukin 1 Receptor Antagonist Protein / Q000097:blood; D016753:Interleukin-10 / Q000097:blood; D015850:Interleukin-6 / Q000097:blood; D007552:Isotonic Solutions; D008297:Male; D016343:Monitoring, Intraoperative; D047889:Receptors, Tumor Necrosis Factor, Type II / Q000097:blood; D000683:Serum Amyloid P-Component / Q000032:analysis; D000099153:Pentraxins
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein; D002630:Chemotactic Factors; D000077324:Crystalloid Solutions; D053590:Interleukin 1 Receptor Antagonist Protein; D016753:Interleukin-10; D015850:Interleukin-6; D007552:Isotonic Solutions; D047889:Receptors, Tumor Necrosis Factor, Type II; D000683:Serum Amyloid P-Component; D000099153:Pentraxins