Elkinton: The treatment of shock due to salt depletion, comparison of the hemodynamic effects of isotonic saline, of hypertonic saline, and of isotonic glucose solutions

In the preceding paper, the peripheral vascular collapse induced in untraumatized dogs by the removal of sodium chloride has been described (1). In its effects on plasma volume, plasma protein, blood pressure, cardiac output, and circu-lation rate this type of peripheral vascular collapse is indistinguishable from that observed in trau-matic shock. Depletion of water without salt, on the other hand, depresses the circulation much less severely. The reasons for this are not clear. Comparable contractions of extracellular volumes can be obtained in both, but their effects on the tonicity and distribution of body fluids are dia-metrically opposed. Salt depletion causes intra-cellular overhydration and generalized hypotoni-city, while water depletion causes intracellular dehydration and generalized hypertonicity. Salt deprivation is associated with a considerable loss of protein from the circulating plasma while water depletion is not. Whether this is a cause or an effect of the severe vascular collapse could not be determined. The present experiments seek further to char-acterize these differences in the effects of the two procedures by studying the response of salt de-pletion shock to therapy. Isotonic glucose infu-sions will reexpand the extracellular volume, in-crease the intracellular overhydration, and make both compartments still more hypotonic. Isotonic and hypertonic saline infusions, on the other hand, while reexpanding the extracellular volume also will relieve intracellular overhydration and correct the generalized hypotonicity. By a com-parison of the effect of these two procedures o