The total carbonate content of the arterial and venous plasma in patients with chronic heart disease

Abstract

Twenty-eight determinations of the total carbon dioxide content of the arterial and venous plasma have been made on ten individuals with chronic heart disease. All patients in this group have been carefully selected because they were suffering primarily from a failure of the heart to maintain an adequate circulation. They have been free as far as could be determined from any vascular or renal disease. For the most part they were young patients with chronic rheumatic myocarditis and valvulitis.

In some a normal cardiac mechanism was present, as determined by the electrocardiograph. In others auricular fibrillation usually associated with mitral stenosis was found. Moribund patients and patients with a marked degree of venous stasis and edema have not been included.

Samples of the arterial and venous blood were obtained at the same operation; immediately centrifuged, and the total CO₂ content of the separated plasma determined directly. In all cases the blood was obtained while the patient was at rest in bed. The results are presented in the accompanying table.

It is seen that both the arterial and venous plasma have a total CO₂ lower than that found in normal individuals. The arterial values for C0₂ show wider variation and the discrepancy between the CO₂ of the arterial and venous plasma is more marked in heart cases than in normal individuals. These differences are attributed to the varying degrees of cardiac efficiency in the heart patients.

In the type of cases studied there has been a certain relation between the integrity of the circulation and the level of CO₂ in the plasma. The more dyspneic the patient the lower has been the C0₂ in the arterial plasma. The following case will serve as an example: A patient walked into the hospital complaining of shortness of breath.