title: Fluid replacement and respiratory function: comparison of whole blood with colloid and crystalloid: A randomised animal study.
abstract: BACKGROUND
  Fluid replacement with blood products, colloids and crystalloids is associated with morbidity and mortality. Despite this, the consequences of fluid administration on airway and respiratory tissue properties are not fully understood.
  
  
  OBJECTIVE
  Comparison of respiratory effects of fluid replacement with autologous blood (Group B), colloid (HES 6% 130/0.4, Group CO) or crystalloid solution (NaCl 0.9%, Group CR) after haemorrhage with separate assessments of airway resistance and respiratory tissue mechanics.
  
  
  METHODS
  A randomised study.
  
  
  METHODS
  An experimental model of surgical haemorrhage and fluid replacement in rats.
  
  
  METHODS
  Anaesthetised, ventilated rats randomly allocated into three groups (Group B: n = 8, Group CO: n = 8, Group CR: n = 9).
  
  
  METHODS
  Animals were bled in six sequential steps, each manoeuvre targeting a loss of 5% of total blood volume. The blood loss was then replaced stepwise in a 1 : 1 ratio with one of the three fluids.
  
  
  METHODS
  After each step, airway resistance (Raw), tissue damping and elastance (H) were determined by forced oscillations. Oedema indices from lung weights and histology were also measured.
  
  
  RESULTS
  Raw (mean ± SD) decreased in all groups following blood loss (-20.3 ± 9.5% vs. baseline, P < 0.05), and remained low following blood replacement (-21.7 ± 14.5% vs. baseline, P < 0.05), but was normalised by colloid (5.5 ± 10.7%, NS). Crystalloid administration exhibited an intermediate reversal effect (-8.4 ± 14.7%, NS). Tissue viscoelasticity increased following both blood loss and replacement, with no evidence of a significant difference in H between Groups CO and CR. More severe oedema was observed in Groups CR and CO than in Group B (P < 0.05), with no difference between the colloid and crystalloid solutions.
  
  
  CONCLUSIONS
  This model, which mimics surgical haemorrhage, yields no evidence of a difference between colloids and crystalloids with regard to the pulmonary consequences of blood volume restoration. Functional changes in the lung should not be a key concern when choosing fluid replacement therapy with these solutions.
authors.affiliation: From the Department of Medical Physics and Informatics (GHF, DC, FP), Department of Anaesthesiology and Intensive Therapy, University of Szeged, Szeged, Hungary (BB, ÁLB), Pathophysiological Experimental Platform, Department of Anaesthesiology, Pharmacology and Intensive Care, University of Geneva (CD), Paediatric Anaesthesia Unit, Geneva Children's Hospital, University Hospitals of Geneva, Geneva, Switzerland (WH), and Université de Picardie Jules Verne, Inserm U1105 and Paediatric Lung Function Laboratory, CHU Amiens, Amiens, France (SB).
authors.forename: Gergely H
authors.initials: GH
authors.lastname: Fodor
authors.forename: Barna
authors.initials: B
authors.lastname: Babik
authors.forename: Dorottya
authors.initials: D
authors.lastname: Czövek
authors.forename: Camille
authors.initials: C
authors.lastname: Doras
authors.forename: Ádám L
authors.initials: ÁL
authors.lastname: Balogh
authors.forename: Sam
authors.initials: S
authors.lastname: Bayat
authors.forename: Walid
authors.initials: W
authors.lastname: Habre
authors.forename: Ferenc
authors.initials: F
authors.lastname: Peták
mesh_terms: D000818:Animals; D016063:Blood Loss, Surgical; D003102:Colloids / Q000008:administration & dosage; D000077324:Crystalloid Solutions; D004195:Disease Models, Animal; D005440:Fluid Therapy / Q000379:methods*; D006895:Hydroxyethyl Starch Derivatives / Q000008:administration & dosage*; D007552:Isotonic Solutions / Q000008:administration & dosage*; D008297:Male; D010952:Plasma Substitutes / Q000008:administration & dosage; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012119:Respiration; D012129:Respiratory Function Tests
chemical_list: D003102:Colloids; D000077324:Crystalloid Solutions; C485123:HES 130-0.4; D006895:Hydroxyethyl Starch Derivatives; D007552:Isotonic Solutions; D010952:Plasma Substitutes