title: Hematology patterns after hemoglobin-based oxygen carrier resuscitation from severe controlled hemorrhage with prolonged delayed definitive care.
abstract: BACKGROUND
  The hemoglobin-based oxygen carrier (HBOC-201) resuscitation fluid improves outcome in hemorrhagic shock swine models with minimal coagulopathy. Herein, coagulation parameters were evaluated after resuscitation with HBOC-201 after severe bleeding and prolonged delay to definitive care.
  
  
  METHODS
  After 55 percent estimated blood volume-controlled hemorrhage by catheter withdrawal, swine (n=48) were resuscitated with HBOC-201 or Hextend (HEX) infused in four doses over 4 hours or not resuscitated (NON). Animals were randomly assigned in two cohorts of 4- or 24-hour simulated delay to hospital arrival (access to blood and saline infusions up to 72 hr). In vitro hematologic monitoring was assessed with complete blood count, hemostasis (thromboelastography [TEG], in vitro bleeding time [PFA]), and coagulation (prothrombin time [PT], thrombin-antithrombin, fibrinogen) indices.
  
  
  RESULTS
  Within groups, survival was unaffected by extending delay from 4 to 24 hours. Combined survival was similar for HBOC-201 and HEX but lower for NON animals (93.5, 81.5, and 25 percent, respectively; p<0.01). Blood transfusion requirements were lower with HBOC-201 than HEX. Elevated TEG and PFA parameters in resuscitated animals reflected fluid and blood transfusion regimens. TEG reaction time and PFA were transiently higher with HBOC-201 than with HEX during the early hospital phase. PT was increased in HEX animals.
  
  
  CONCLUSIONS
  In this severe model, survival was equivalent with HBOC-201 and HEX resuscitation. HBOC-201 or HEX allowed delayed hospital arrival to 24 hours without worsening coagulation parameters, but dilutional mild coagulopathy in the hospital phase persisted with HBOC-201 due to blood transfusion avoidance. Low hematocrit suggests that blood administration after HBOC-201 resuscitation could be beneficial to replete blood cellular mass.
authors.affiliation: Trauma and Resuscitative Medicine Department, Naval Medical Research Center, Silver Spring, Maryland 20910-7500, USA. arnaudf@nmrc.navy.mil
authors.forename: Francoise
authors.initials: F
authors.lastname: Arnaud
authors.forename: Daniel
authors.initials: D
authors.lastname: Fasipe
authors.forename: Nora
authors.initials: N
authors.lastname: Philbin
authors.forename: Jennifer
authors.initials: J
authors.lastname: Rice
authors.forename: W Shannon
authors.initials: WS
authors.lastname: Flournoy
authors.forename: Stephen
authors.initials: S
authors.lastname: Ahlers
authors.forename: Richard
authors.initials: R
authors.lastname: McCarron
authors.forename: Daniel
authors.initials: D
authors.lastname: Freilich
mesh_terms: D000818:Animals; D001777:Blood Coagulation; D001780:Blood Coagulation Tests; D001802:Blood Substitutes / Q000627:therapeutic use*; D001803:Blood Transfusion; D006403:Hematologic Tests; D006454:Hemoglobins / Q000627:therapeutic use*; D006470:Hemorrhage / Q000628:therapy*; D012151:Resuscitation / Q000379:methods*; D013552:Swine; D013997:Time Factors
chemical_list: D001802:Blood Substitutes; D006454:Hemoglobins; C096798:HBOC 201