Further aspects of fluid substitution

Abstract

Other things being equal the ideal therapy would appear to be to restore the volume that has been lost. But, as we know, other things are not the same after a period of stagnant anoxia. The purpose must then be to increase capillary blood flow adequately to reverse the metabolic acidosis and to meet the functional demands of the tissues. In this symposium “irreversible shock” has repeatedly been defined as the state in which volume replacement fails to achieve survival and recovery. It has also been stated or implied that the defect lies in the microcirculation. Dr Gelin’s investigations with high and low molecular dextran provide rather good evidence that this is indeed the crux of “irreversibility”, at least in hypovolemic stagnant anoxia. Further, Dr. Gelin’s correlations of changes in fluidity of the plasma and whole blood at low sheer rates with changes in capillary flow, directly observed, and with the reversal of the metabolic acidosis, show that the influence of plasma substitutes on the physical properties of the perfusing blood can be of critical importance. This appears to me to be a valuable contribution, and it serves to remind us that when we use the term “irreversible shock” we only mean that we have not yet found the cure. Here, then, the studies on LMD may very well be what is popularly referred to as a “break-through”. This work may also have useful applications in some forms of peripheral vascular occlusive disease.