title: Hepatic and pulmonary apoptosis after hemorrhagic shock in swine can be reduced through modifications of conventional Ringer's solution.
abstract: BACKGROUND
  Cytotoxic properties of racemic (D-,L-isomers) lactated Ringer's solution detected in vitro and in small animal experiments, have not been confirmed in large animal models. Our hypothesis was that in a clinically relevant large animal model of hemorrhage, resuscitation with racemic lactated Ringer's solution would induce cellular apoptosis, which can be attenuated by elimination of d-lactate.
  
  
  METHODS
  Yorkshire swine (n = 49, weight 40-58 kg) were subjected to uncontrolled (iliac arterial and venous injuries) and controlled hemorrhage, totaling 40% of estimated blood volume. They were randomized (n = 7/group) to control groups, which consisted of (1) no hemorrhage (NH), (2) no resuscitation (NR), or resuscitation groups, which consisted of (3) 0.9% saline (NS), (4) racemic lactated Ringer's (DL-LR), (5) L-isomer lactated Ringer's (L-LR), (6) Ketone Ringer's (KR), (7) 6% hetastarch in 0.9% saline (Hespan). KR was identical to LR except for equimolar substitution of lactate with beta-hydroxybutyrate. Resuscitation was performed in three phases, simulating (1) prehospital, (2) operative, (3) postoperative/recovery periods. Arterial blood gasses, circulating cytokines (TNF-alpha, IL-1, -6, -10), and markers of organ injury were serially measured. Metabolic activity of brain, and liver, was measured with microdialysis. Four hours postinjury, organs were harvested for Western blotting, ELISA, TUNEL assay, and immunohistochemistry.
  
  
  RESULTS
  All resuscitation strategies restored blood pressure, but clearance of lactic acidosis was impeded following DL-LR resuscitation. Metabolic activity decreased during shock and improved with resuscitation, without any significant inter-group differences. Levels of cytokines in circulation were similar, but tissue levels of TNF in liver and lung increased six- and threefolds (p < 0.05) in NR group. In liver, all resuscitation strategies significantly decreased TNF levels compared with the NR group, but in the lung resuscitation with lactated Ringer (DL and L isomers) failed to decrease tissue TNF levels. DL-LR resuscitation also increased apoptosis (p < 0.05) in liver and lung, which was not seen after resuscitation with other solutions.
  
  
  CONCLUSIONS
  In this large animal model of hemorrhagic shock, resuscitation with conventional (racemic) LR solution increased apoptotic cell death in liver and lung. This effect can be prevented by simple elimination of D-lactate from the Ringer's solution.
authors.affiliation: Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA.
authors.forename: Eduardo C
authors.initials: EC
authors.lastname: Ayuste
authors.forename: Huazhen
authors.initials: H
authors.lastname: Chen
authors.forename: Elena
authors.initials: E
authors.lastname: Koustova
authors.forename: Peter
authors.initials: P
authors.lastname: Rhee
authors.forename: Naresh
authors.initials: N
authors.lastname: Ahuja
authors.forename: Zhang
authors.initials: Z
authors.lastname: Chen
authors.forename: C Robert
authors.initials: CR
authors.lastname: Valeri
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Spaniolas
authors.forename: Tina
authors.initials: T
authors.lastname: Mehrani
authors.forename: Hasan B
authors.initials: HB
authors.lastname: Alam
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D004195:Disease Models, Animal; D006801:Humans; D007375:Interleukin-1 / Q000097:blood; D016753:Interleukin-10 / Q000097:blood; D007536:Isomerism; D007552:Isotonic Solutions / Q000737:chemistry* / Q000494:pharmacology* / Q000627:therapeutic use; D008099:Liver / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D008168:Lung / Q000187:drug effects* / Q000378:metabolism / Q000473:pathology; D012151:Resuscitation; D000077325:Ringer's Lactate; D012771:Shock, Hemorrhagic / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D013552:Swine; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism
chemical_list: D007375:Interleukin-1; D007552:Isotonic Solutions; D000077325:Ringer's Lactate; D014409:Tumor Necrosis Factor-alpha; D016753:Interleukin-10