The effects of hyperoxic ventilation in the treatment of myocardial infarction

Abstract

SUMMARY Everyone supports the use of oxygen therapy to treat hypoxia secondary to acute myocardial infarction. However, the literature is confusing on the subject of supplemental oxygenation of patients with normal oxygen saturation and uncomplicated acute myocardial infarction, despite the fact that controlled randomized human studies have failed to support the need for supplemental oxygen in the uncomplicated patient. Both normobaric and hyperbaric oxygen must be recognized as a vasoactive substance and thus be considered a drug to which the patient may have an adverse response, particularly in patients whose oxygen saturation is 95% or greater, for example, coronary vasoconstriction. The level of evidence for the use of normobaric oxygenation in uncomplicated acute myocardial infarction patients who were not hypoxemic is based on expert opinion, case studies and ‘standard of care’. Hyperbaric oxygen therapy has not been shown to be beneficial in human studies. Most studies of the use of supplemental oxygen in humans with acute myocardial infarction were performed prior to modern aggressive medical therapy and current thrombolytic or percutaneous coronary intervention therapy. Perhaps a randomized clinical trial in patients with normal oxygen saturations and modern therapy will shed some light on the subject.