title: Response to fluid boluses in the fluid and catheter treatment trial.
abstract: BACKGROUND
  Recent emphasis has been placed on methods to predict fluid responsiveness, but the usefulness of using fluid boluses to increase cardiac index in critically ill patients with ineffective circulation or oliguria remains unclear.
  
  
  METHODS
  This retrospective analysis investigated hemodynamic responses of critically ill patients in the ARDS Network Fluid and Catheter Treatment Trial (FACTT) who were given protocol-based fluid boluses. Fluid responsiveness was defined as ≥ 15% increase in cardiac index after a 15 mL/kg fluid bolus.
  
  
  RESULTS
  A convenience sample of 127 critically ill patients enrolled in FACTT was analyzed for physiologic responses to 569 protocolized crystalloid or albumin boluses given for shock, low urine output (UOP), or low pulmonary artery occlusion pressure (PAOP). There were significant increases in mean central venous pressure (9.9 ± 4.5 to 11.1 ± 4.8 mm Hg, P < .0001) and mean PAOP (11.6 ± 3.6 to 13.3 ± 4.3 mm Hg, P < .0001) following fluid boluses. However, there were no significant changes in UOP, and there were clinically small changes in heart rate, mean arterial pressure, and cardiac index. Only 23% of fluid boluses led to a ≥ 15% change in cardiac index. There was no significant difference in the frequency of fluid responsiveness between boluses given for shock or oliguria vs boluses given only for low PAOP (24.0% vs 21.8%, P = .59). There were no significant differences in 90-day survival, need for hemodialysis, or return to unassisted breathing between patients defined as fluid responders and fluid nonresponders.
  
  
  CONCLUSIONS
  In this cohort of critically ill patients with ARDS who were previously resuscitated, the rate of fluid responsiveness was low, and fluid boluses only led to small hemodynamic changes.
authors.affiliation: Louisiana State University Health Sciences Center, New Orleans, LA. Electronic address: mlammi@lsuhsc.edu.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Lammi
authors.affiliation: Louisiana State University Health Sciences Center, New Orleans, LA.
authors.forename: Brianne
authors.initials: B
authors.lastname: Aiello
authors.affiliation: Louisiana State University Health Sciences Center, New Orleans, LA.
authors.forename: Gregory T
authors.initials: GT
authors.lastname: Burg
authors.affiliation: Louisiana State University Health Sciences Center, New Orleans, LA.
authors.forename: Tayyab
authors.initials: T
authors.lastname: Rehman
authors.affiliation: University of Colorado, Denver, CO.
authors.forename: Ivor S
authors.initials: IS
authors.lastname: Douglas
authors.affiliation: Vanderbilt University Medical Center, Nashville, TN.
authors.forename: Arthur P
authors.initials: AP
authors.lastname: Wheeler
authors.affiliation: Louisiana State University Health Sciences Center, New Orleans, LA.
authors.forename: Bennett P
authors.initials: BP
authors.lastname: deBoisblanc
mesh_terms: D002405:Catheterization, Central Venous / Q000379:methods*; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D005500:Follow-Up Studies; D006439:Hemodynamics / Q000502:physiology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D016896:Treatment Outcome