Hemodynamlc Effects of Hyperbaric Oxygenation in Experimental Acute Myocardial Infarction

• Hyperbaric oxygenation has been reported to be beneficial in a variety of conditions characterized by ischemia. The rationale for its use in acute myocardial infarction, as in other ischemic conditions, depends on the fact that the amount of physically dissolved oxygen in the capillaries, and hence potentially available for the tissues, is directly related to its partial pressure in the capillaries. With the inhalation of 100$ oxygen at three atmospheres (absolute) pressure, the arterial p(\» rises, theoretically, to about 2200 mm Hg as compared to a level of about 100 mm Hg when room air is breathed. The amount of oxygen physically dissolved in the blood plasma rises from 0.3 vol % when breathing room air to about 6 vol % when breathing 10035 oxygen at three atmospheres pressure. Previous studies of the use of hyperbaric oxygenation in experimental myocardial infarction have shown: protection against ventricular fibrillation in dogs breathing oxygen at two atmospheres following coronary artery ligation; diminution in the size of the myocardial infarction produced by coronary artery ligation in dogs breathing oxygen at three atmospheres compared to those breathing room air; and less rise in serum glutamic oxalacetic transaminase and serum glutamic pyruvic transaminase levels following coronary artery ligation in dogs breathing oxygen