title: Different effects of fluid loading with saline, gelatine, hydroxyethyl starch or albumin solutions on acid-base status in the critically ill.
abstract: BACKGROUND
  Fluid administration in critically ill patients may affect acid-base balance. However, the effect of the fluid type used for resuscitation on acid-base balance remains controversial.
  
  
  METHODS
  We studied the effect of fluid resuscitation of normal saline and the colloids gelatine 4%, hydroxyethyl starch (HES) 6%, and albumin 5% on acid-base balance in 115 clinically hypovolemic critically ill patients during a 90 minute filling pressure-guided fluid challenge by a post-hoc analysis of a prospective randomized clinical trial.
  
  
  RESULTS
  About 1700 mL was infused per patient in the saline and 1500 mL in each of the colloid groups (P<0.001). Overall, fluid loading slightly decreased pH (P<0.001) and there was no intergroup difference. This mildly metabolic acidifying effect was caused by a small increase in chloride concentration and decrease in strong ion difference in the saline- and HES-, and an increase in (uncorrected) anion gap in gelatine- and albumin-loaded patients, independent of lactate concentrations.
  
  
  CONCLUSIONS
  In clinically hypovolemic, critically ill patients, fluid resuscitation by only 1500-1700 mL of normal saline, gelatine, HES or albumin, resulted in a small decrease in pH, irrespective of the type of fluid used. Therefore, a progressive metabolic acidosis, even with increased anion gap, should not be erroneously attributed to insufficient fluid resuscitation.
  
  
  BACKGROUND
  ISRCTN Registry ISRCTN19023197.
authors.affiliation: Department of Intensive Care, Vrije Universiteit Medical Center, Amsterdam, The Netherlands.
authors.forename: Angélique M E
authors.initials: AM
authors.lastname: Spoelstra-de Man
authors.affiliation: Department of Internal Medicine, Ziekenhuis Amstelland, Amstelveen, The Netherlands.
authors.forename: Annemieke
authors.initials: A
authors.lastname: Smorenberg
authors.affiliation: Department of Intensive Care, Erasmus Medical Center, Rotterdam, The Netherlands.
authors.forename: A B Johan
authors.initials: AB
authors.lastname: Groeneveld
mesh_terms: D000418:Albumins / Q000627:therapeutic use*; D016638:Critical Illness / Q000628:therapy*; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D005780:Gelatin / Q000627:therapeutic use*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D006895:Hydroxyethyl Starch Derivatives / Q000627:therapeutic use*; D008297:Male; D008875:Middle Aged; D012965:Sodium Chloride / Q000627:therapeutic use*
chemical_list: D000418:Albumins; D006895:Hydroxyethyl Starch Derivatives; D012965:Sodium Chloride; D005780:Gelatin