Sympathomimetic Agents in the Treatment of Shock

Sympathomimetic drugs can be very useful in the treatment of shock but only when used as part of an overall therapeutic plan to improve tissue perfusion and deal with the pathophysiological abnormalities in each situation. They can be classified according to [1] the target organ, [2] the type of action (direct or indirect), and [3] the specific adrenergic receptor stimulated. In addition, secondary effects, such as the influence of increased arterial pressure on cardiac function, must be taken into account. Vasodilatation or vasoconstriction might not be equal in all vascular beds, and the effect of either can be markedly influenced by local vascular lesions. The choice of the most effective agent, therefore, entails careful balance between its effects and the hemodynamic disorder—hence, the need for careful, continuous monitoring for diagnosis, follow-up, and readjustment of treatment. Occasionally, a combination of drugs can help achieve a proper balance between cardiac and peripheral effects.