Blood volume, hemodynamic, and metabolic changes in hemorrhagic shock in normal and splenectomized dogs.

CHIEN, SHU, ROBERT J. DELLENBACK, SHUNICHI USAMI, DAVID A. BURTON, PAUL F. GUSTAVSON, AND VOJISLAV MAGAZINOVIC. Blood volume, hemodynamic, and metabolic changes in hemorrhagic shock in normal and splenectomized dogs. Am. J. Physiol. 225(4): 866-879. 1973.-Normal and splenectomized beagles were subjected to 3 hr of oligemic hypotension. Presence of the spleen was associated with larger bleeding volume, lesser transcapillary fluid influx, and higher values for hematocrit, viscosity, and total peripheral resistance (TPR). In late oligemia and following retransfusion, the nonsurviving normal dogs showed a loss of blood volume and elevations of viscosity and TPR. These changes were not found in the splenectomized dogs, which instead showed signs of cardiac insufficiency. Therefore, peripheral and cardiac failure may assume differential importance depending on the presence of the spleen. In early oligemia the nonsurvivals showed higher values of excess lactate, base deficit, and uric acid than the survivals; but the differences in base deficit and excess lactate diminished or reversed in late oligemia and after retransfusion. Several approaches in analyzing circulatory and metabolic changes in low flow states have been introduced, including the calculations of ultrafiltrate gain, vascular hindrance, and alactacid base deficit.