Abnormal heme-protein patterns in hemorrhagic shock.

Allegedly toxic heme pigments have been described in the serum of animals bled to hemorrhagic shock (5,7). In addition, Sears et al. (9), and Braun et al. (1) have shown that the products derived from the degradation of hemoglobin following intravascular hemolysis were toxic (heme carried by hemopexin and albumin). The accumulation of metabolites, caused by the impeded circulation, degrades free hemoglobin into heme pigments and their concentration then reaches a level which exceeds the normal heme-carrying capacity of serum proteins. We have already demonstrated the presence of abnormal heme pigments in clinical cases of shock using scanning spectrophotometry (3). We have endeavored to identify these pigments by serum electrophoresis, and to relate the appearance of some of these compounds to mortality rates. There were no deaths associated with the presence of haptoglobin-hemoglobin alone in serum. As shock deepened and mortality rose, hemopexin-heme and methemalbumin appeared. The highest mortality rate (4 out of 5 cases) was found when both hemopexin-heme and methemalbumin were present. It appears, therefore, that the administration of serum proteins in shock may reduce the toxicity of the products of degradation formed in low-flow states.