title: Evaluation of the effect of hetastarch and lactated Ringer's solution on plasma colloid osmotic pressure in healthy llamas.
abstract: OBJECTIVE
  To compare the effects of hetastarch and lactated Ringer's solution (LRS) on plasma colloid osmotic pressure (pCOP) and other hematologic variables in healthy llamas.
  
  
  METHODS
  Prospective crossover study.
  
  
  METHODS
  6 healthy female llamas. Procedures-Llamas were administered LRS (45 mL/kg [20.5 mL/lb]) and, after a 3-day washout period, hetastarch (15 mL/kg [6.8 mL/lb]) during 60-minute IV infusions. Serum total protein, serum albumin, and hemoglobin concentrations and Hct were measured before each infusion (baseline), immediately after each infusion was completed (0 hours), and at 2, 4, 8, and 12 hours. The pCOP was measured at baseline and at 0, 2, 4, 8, 12, 24, 36, and 48 hours after each infusion was completed; additional measurements of pCOP were obtained 72 and 96 hours after hetastarch infusion.
  
  
  RESULTS
  Hetastarch administration significantly increased mean ± SEM pCOP from 23.5 ± 0.3 mm Hg (baseline) to a peak of 28.4 ± 0.6 mm Hg (12 hours); significant increases in pCOP persisted at 96 hours after hetastarch administration. Administration of LRS significantly decreased albumin and total protein concentrations; in addition, mean ± SEM pCOP decreased from 24.1 ± 0.4 mm Hg (baseline) to 18.0 ± 0.3 mm Hg (0 hours). Hetastarch administration caused more pronounced decreases in Hct (0 hours) and concentrations of hemoglobin (0 hours), albumin (all time points), and total protein (all time points) than did LRS administration.
  
  
  CONCLUSIONS
  Hetastarch administration increased pCOP in healthy llamas for 96 hours with no clinically important complications.
authors.affiliation: Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, Corvallis, OR 97331, USA.
authors.forename: Katelyn R
authors.initials: KR
authors.lastname: Carney
authors.forename: Erica C
authors.initials: EC
authors.lastname: McKenzie
authors.forename: Craig A
authors.initials: CA
authors.lastname: Mosley
authors.forename: Mark E
authors.initials: ME
authors.lastname: Payton
mesh_terms: D000818:Animals; D002161:Camelids, New World / Q000502:physiology*; D003102:Colloids; D018592:Cross-Over Studies; D005260:Female; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage* / Q000494:pharmacology*; D007552:Isotonic Solutions / Q000008:administration & dosage* / Q000494:pharmacology*; D009997:Osmotic Pressure / Q000502:physiology*; D000077325:Ringer's Lactate
chemical_list: D003102:Colloids; D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; D000077325:Ringer's Lactate