title: Oxygen debt and metabolic acidemia as quantitative predictors of mortality and the severity of the ischemic insult in hemorrhagic shock.
abstract: METHODS
  An experimental canine model of hemorrhagic, hypovolemic shock is described that uses oxygen debt and its metabolic consequences of lactic acidemia and metabolic base deficit as independent variables for the prediction of probability of death.
  
  
  RESULTS
  Lactic acidemia and metabolic base deficit are compared with the conventional hemodynamic variables of BP and cardiac output (Qt) as predictors of outcome and are shown to be superior using a modified Kaplan-Meier probability statistic. The LD50 for oxygen debt is shown to be 113.5 mL/kg, 12.9 mmol/L for lactate, and -18.8 mmol/L for base excess (BE). Comparison is made between the ability of Qt, BP, shed blood, BE, and lactate to predict oxygen debt.
  
  
  CONCLUSIONS
  Of the single-variable predictors, BE shows the highest explained variability. However, a combined prediction from both lactate and BE appears superior to the use of either alone. Using this regression to compute the oxygen debt, it is possible to estimate accurately the actual level of oxygen debt from the BE and lactate values obtained during hemorrhagic hypovolemia. From serial determinations over time of the increase in these biochemical variables above the oxygen debt baseline, it is possible to estimate the rate of oxygen debt accumulation and the time remaining until the LD50 will be reached as indicators of the severity of the total body ischemia resulting from hemorrhagic shock.
authors.affiliation: Department of Surgery, University of Maryland.
authors.forename: C M
authors.initials: CM
authors.lastname: Dunham
authors.forename: J H
authors.initials: JH
authors.lastname: Siegel
authors.forename: L
authors.initials: L
authors.lastname: Weireter
authors.forename: M
authors.initials: M
authors.lastname: Fabian
authors.forename: S
authors.initials: S
authors.lastname: Goodarzi
authors.forename: P
authors.initials: P
authors.lastname: Guadalupi
authors.forename: L
authors.initials: L
authors.lastname: Gettings
authors.forename: S E
authors.initials: SE
authors.lastname: Linberg
authors.forename: T C
authors.initials: TC
authors.lastname: Vary
mesh_terms: D000136:Acid-Base Equilibrium; D000244:Adenosine Diphosphate / Q000378:metabolism; D000249:Adenosine Monophosphate / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D001794:Blood Pressure; D001810:Blood Volume; D002302:Cardiac Output; D004285:Dogs; D007773:Lactates / Q000097:blood; D008099:Liver / Q000378:metabolism; D008297:Male; D008954:Models, Biological; D010100:Oxygen / Q000378:metabolism*; D011336:Probability; D012771:Shock, Hemorrhagic / Q000097:blood / Q000378:metabolism* / Q000401:mortality / Q000503:physiopathology
chemical_list: D007773:Lactates; D000249:Adenosine Monophosphate; D000244:Adenosine Diphosphate; D000255:Adenosine Triphosphate; D010100:Oxygen