title: Balanced vs unbalanced crystalloid resuscitation in a near-fatal model of hemorrhagic shock and the effects on renal oxygenation, oxidative stress, and inflammation.
abstract: BACKGROUND
  The aim of the present study was to test the hypothesis that balanced crystalloid resuscitation would be better for the kidney than unbalanced crystalloid resuscitation in a rat hemorrhagic shock model.
  
  
  METHODS
  Male Wistar rats were randomly assigned to four groups (n=6/group): (1) time control; (2) hemorrhagic shock control; (3) hemorrhagic shock followed by unbalanced crystalloid resuscitation (0.9% NaCl); and (4) hemorrhagic shock followed by acetate and gluconate-balanced crystalloid resuscitation (Plasma Lyte). We tested the solutions for their effects on renal hemodynamics and microvascular oxygenation, strong-ion difference, systemic and renal markers of inflammation and oxidative stress including glycocalyx degradation as well as their effects on renal function.
  
  
  RESULTS
  The main findings of our study were that: (1) both the balanced and unbalanced crystalloid solutions successfully restored the blood pressure, but renal blood flow was only recovered by the balanced solution although this did not lead to improved renal microvascular oxygenation; (2) while unbalanced crystalloid resuscitation induced hyperchloremia and worsened metabolic acidosis in hemorrhaged rats, balanced crystalloid resuscitation prevented hyperchloremia, restored the acid-base balance, and preserved the anion gap and strong ion difference in these animals; (3) in addition balanced crystalloid resuscitation significantly improved renal oxygen consumption (increased VO(2), decreased  [Formula: see text] ); and (4) however neither balanced nor unbalanced crystalloid resuscitation could normalize systemic inflammation or oxidative stress. Functional immunohistochemistry biomarkers showed improvement in L-FABP in favor of balanced solutions in comparison to the hemorrhagic group although no such benefit was seen for renal tubular injury (measured by NGAL) by giving either unbalanced or balanced solutions.
  
  
  CONCLUSIONS
  Although balanced crystalloid resuscitation seems superior to balanced crystalloid resuscitation in protecting the kidney after hemorrhagic shock and is certainly better than not applying fluid resuscitation, these solutions were not able to correct systemic inflammation or oxidative stress associated with hemorrhagic shock.
authors.affiliation: Department of Translational Physiology, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands. uguraksu@istanbul.edu.tr
authors.forename: Ugur
authors.initials: U
authors.lastname: Aksu
authors.forename: Rick
authors.initials: R
authors.lastname: Bezemer
authors.forename: Berna
authors.initials: B
authors.lastname: Yavuz
authors.forename: Asli
authors.initials: A
authors.lastname: Kandil
authors.forename: Cihan
authors.initials: C
authors.lastname: Demirci
authors.forename: Can
authors.initials: C
authors.lastname: Ince
mesh_terms: D000818:Animals; D000077324:Crystalloid Solutions; D004573:Electrolytes / Q000008:administration & dosage; D005440:Fluid Therapy; D006439:Hemodynamics; D006820:Hyaluronic Acid / Q000097:blood; D007249:Inflammation; D007552:Isotonic Solutions / Q000008:administration & dosage*; D007668:Kidney / Q000378:metabolism* / Q000473:pathology; D008297:Male; D008315:Malondialdehyde / Q000097:blood; D018384:Oxidative Stress; D010101:Oxygen Consumption; D010952:Plasma Substitutes / Q000008:administration & dosage*; D051381:Rats; D017208:Rats, Wistar; D012079:Renal Circulation; D012151:Resuscitation; D012771:Shock, Hemorrhagic / Q000503:physiopathology / Q000628:therapy*
chemical_list: D000077324:Crystalloid Solutions; D004573:Electrolytes; D007552:Isotonic Solutions; D010952:Plasma Substitutes; D008315:Malondialdehyde; D006820:Hyaluronic Acid; C048013:Plasmalyte A