ALKALINIZING AGENTS AND FLUID PRIMING IN HEMORRHAGIC SHOCK

Abstract

With the revival of interest in the contribution of acidosis as a primary factor in the development of hemorrhagic shock, it was decided to test the value of correcting the acidosis developed after 90 mins. of hypotension by means of NaHCO3 and Na lactate. It was observed that neither of these agents, when introduced intraven. as supplements to the reinfusion of all previously withdrawn blood at the end of the 90 min. hypotension period (40-45 mm. Hg) had any effect whatsoever on the mortality rate established in a control series. These results support the authors'' contention that, despite the apparently favorable behaviour of an animal, no known remedial measure can exert other than temporarily beneficial effects when administered after an irreversible state, as recognized by definite criteria, has developed. Evidence of a circumstantial nature was cited to demonstrate that the admn. of alkalinizing agents during the impending shock state may prevent or delay the transition to the irreversible state. The failure of many animals to show continuous hemodilution for at least the major portion of the 90 min. hemorrhagic-hypotension period shows that this process may have been restricted by an inadequate initial state of hydration. This compensatory mechanism was improved in many animals which had received (before hemorrhage) an intravenous injn. of saline equivalent to 5% of their body wt. The striking reduction in the mortality rate when compared with control animals (55 vs. 75% mortality respectively) in addition to the elimination of "precipitant deaths" and the general prolongation of the post-reinfusion survival times offer strong testimony for the vital role which this compensatory mechanism plays in combatting the stress of severe hemorrhages. It also re-emphasized the importance of maintaining an adequate state of hydration whenever the loss of blood is significant.