The equilibrium of oxygen and hemoglobin is under multifactorial control. Shifts of oxyhemoglobin dissociation curves have been observed in patients with heart disease. Whether such changes, measurable in vitro, merely represent compensatory mechanisms or play a contributory role in the pathogenesis of ischemia is still uncertain. With the development of newer techniques, the actual rate of oxygen release from hemoglobin can be measured, and this may prove to be a more valid measurement of physiologic oxygen release.
Pharmacologic manipulation of oxyhemoglobin equilibrium can be accomplished with various agents, notably propranolol hydrochloride, acetazolamide, and infusion of inosine, phosphorus, and pyruvate. The clinical significance of these effects has not been established, but ultimately they may prove to be useful in improving tissue oxygenation in ischemic conditions.
(JAMA 229:804-808, 1974)