Inhalation Anesthetics in Patients With Cardiac Disease

Abstract

Before we can discuss the effects of anesthetics on the coronary circulation, it seems pertinent to discuss the basic control mechanisms involved in the coronary circulation. It is fair to say that the coronary circulation is one of if not the most “responsive” circulations in the body. Obviously, the final determinant of flow to any given region of myocardium is the metabolic demand of that region. Unfortunately, although the metabolic demand of a given region might be posing a certain requirement, at any given time, numerous factors may stand in the way of that metabolic demand being totally satisfied. These factors include coronary artery disease, excessive heart rate, rapidly changing afterload, dysrhythmias, as well as various external “tonal” influences such as from sympathetic nerve endings “playing upon” various regions of the heart, plus hormonal influences from the adrenal glands and elsewhere.