Effects of Primary Shock on Cardiac Output and Blood Pressure.

Abstract

In a previous study,1 the effects of uncomplicated hemorrhage on cardiac output and blood pressure were determined. Repeated removal of blood was usually associated with a decline in the cardiac output from 30 to 50% below the normal level before a marked diminution in the blood pressure occurs. Johnson and Blalock2 found that secondary shock as a result of trauma to muscles, trauma to the intestines or burns is associated with a definite decrease in the output of the heart before the blood pressure is altered appreciably. On the contrary, the introduction of histamine2 causes an initial decline in the blood pressure followed by a decrease in the cardiac output. Following the removal of the adrenal glands,3 the blood pressure usually declines before the cardiac output is altered. Trauma to the central nervous system4 is usually associated with a simultaneous decline in both the cardiac output and blood pressure.The alterations in the cardiac output and blood pressure in primary shock were determined in th...