title: The effects of saline or albumin resuscitation on acid-base status and serum electrolytes.
abstract: OBJECTIVE
  To test whether fluid resuscitation with normal saline or 4% albumin is associated with differential changes in acid-base status and serum electrolytes.
  
  
  METHODS
  Nested cohort study.
  
  
  METHODS
  Three general intensive care units.
  
  
  METHODS
  Six hundred and ninety-one critically ill patients.
  
  
  METHODS
  Randomization of patients to receive blinded solutions of either 4% human albumin or normal saline for fluid resuscitation.
  
  
  RESULTS
  Albumin was given to 339 patients and saline to 352. At baseline, both groups had a similar serum bicarbonate, albumin, and base excess levels. After randomization, bicarbonate and base excess increased significantly and similarly over time (p < .0001). On multivariate analysis, fluid resuscitation with albumin predicted a smaller increase in pH (p = .0051), bicarbonate (p = .034), and base excess (p = .015). The amount of fluid was an independent predictor of pH (p < .0001), serum chloride (p < .0001), calcium (p = .0001), bicarbonate (p = .0002), and base excess (p < .0001) on the first day of treatment. In patients who received >3 L of fluids in the first 24 hrs, albumin administration was associated with a significantly greater increase in serum chloride (p = .0026). Acute Physiology and Chronic Health Evaluation II score and the presence of sepsis also independently predicted changes in several electrolytes and acid-base variables.
  
  
  CONCLUSIONS
  When comparing albumin and saline, the choice and amount of resuscitation fluid are independent predictors of acid-base status and serum electrolytes. When large volumes are given, albumin administration leads to a higher chloride concentration. However, overall differences between the types of fluid are minor, whereas the volume of fluid administered is a much stronger predictor of such changes, which are also influenced by illness severity and the passage of time.
authors.affiliation: Department of Intensive Care, Austin Hospital, Melbourne, Australia.
authors.forename: Rinaldo
authors.initials: R
authors.lastname: Bellomo
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Morimatsu
authors.forename: Craig
authors.initials: C
authors.lastname: French
authors.forename: Louise
authors.initials: L
authors.lastname: Cole
authors.forename: David
authors.initials: D
authors.lastname: Story
authors.forename: Shigehiko
authors.initials: S
authors.lastname: Uchino
authors.forename: Toshio
authors.initials: T
authors.lastname: Naka
mesh_terms: D000136:Acid-Base Equilibrium / Q000187:drug effects*; D000418:Albumins / Q000008:administration & dosage / Q000627:therapeutic use*; D001774:Blood Chemical Analysis; D016638:Critical Illness; D004311:Double-Blind Method; D004573:Electrolytes / Q000097:blood*; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012965:Sodium Chloride / Q000008:administration & dosage / Q000627:therapeutic use*
chemical_list: D000418:Albumins; D004573:Electrolytes; D012965:Sodium Chloride