Cardiogenic shock: A review

Abstract

A great expansion of interest has occurred in the syndrome of circulatory shock. The measurement of hemodynamic and metabolic variables in human beings and experimental animals now allows an orderly and integrated approach to the ill patient. In cardiogenic shock the minute output of the acutely iniured heart abruptly decreases with attendant fall in arterial blood pressure, tissue perfusion, and pH. Effective venous return to the right and left heart may be monitored by central venous pressure and pulmonary artery diastolic pressure. If low, infusion of volume expanders alone may be sufficient to reverse the shock syndrome. If drugs are required, a variety of catecholamines with alpha and beta stimulating properties are available, as well as inotropic agents such as digitalis and glucagon. Principles for their selection are discussed. The potential roles and hazards of alpha-and beta-adrenergic blocking agents and steroids are also considered. When limits of pharmacologic resuscitation have been reached, mechanical aid and surgical assistance to the cardiovascular system are available. The latter promises to pe of greater importance in the future.

Myocardial and haemodynamic effects of phentolamine

“…The present pharmacological basis for the therapeutic use of a-adrenoceptor blocking drugs in this situation is that, by antagonizing sympathetic vasoconstrictor tone (particularly at the venous end of the capillary bed), they increase peripheral tissue perfusion. Perlroth & Harrison (1969) have, however, questioned the value of a-adrenoceptor blocking drugs in cardiogenic shock on the grounds that, by lowering diastolic pressure, they may reduce coronary perfusion in patients with an exaggerated left ventricular enddiastolic pressure or with a ' fixed' coronary vascular resistance, a situation where perhaps autoregulation is absent.…”

Cortisol and epinephrine relationships associated with stress adaptation in swine

“…These symptoms have persisted to the present time with the recent addition of intravascular coagulation as a component of hemodynamic change (Wilson e^ al.., 1967;Hirshfeld and Fell, 1969). Blood pooling and perfusion also accompanies shock in a majority of cases (Perlroth and Harrison, 1969;Armstrong, 1970). Once the shock syndrome develops, phys iologic compensatory mechanisms are activated.…”

“…The primary beneficial effects of glucocorti-colds in shock may rest as much on their ability to maintain the integrity of cell membranes and subcellular particles, mitochondria, and lysosomes as upon their ability to influence the dynamics of the circulation (Lillehei et al, 1964). Perlroth and Harrison (1969) reported that corticosteroids are specific for the treatment of shock when it is due to adrenal insufficiency. Topel (1968b) reported that adrenal cortical steroids are associated with stress .…”

“…Administration of steroids (corticosteroid) shows a dose response and has an effect on regional blood flow in the shocked dog resembling the pattern seen with adrenergic blockade . According to Perlroth and Harrison (1969), there is a decrease in blood flow during shock conditions, therefore, agents which lower peripheral resistance and increase flew are desirable. o( adrenergic blocking agents such as phenoxybenzamine and phentolamine have been used for treatment of septic and other forms of shock (Wilson ejt ajL., 1964;Nickerson, 1965;Anderson £t al., 1967 ;Hardaway et^ al., 1967).…”

“…Prolonged reduction or blood to vital areas leads to leLlial cuau&cs Including mCta boiic acidosis as well as stagnation and pooling of blood (Block et al. 1966;Perlroth and Harrison, 1969;Armstrong, 1970).…”