Effect of Reserpine on the Lesser Circulation in Chronic Pulmonary Diseases

Investigations of the effect of pharmacological preparations on pulmonary hypertension in man are important for several reasons: from the potential therapeutic aspect; because these data may help to elucidate the regulation of pressure in the pulmonary artery; and finally because they may show whether pulmonary hypertension is reversible or irreversible.While the effect of reserpine on hypertension in the greater circulation is well known, there are only general papers on the effect of reserpine on hypertension in the lesser circulation.Angelino andLevi (1956) andHalmagyi et al. (1957) demonstrated that pulmonary hypertension can be influenced by reserpine in patients with mitral stenosis.Halmagyi (1959) suggested later that reserpine could be used therapeutically in patients with pulmonary hypertension in chronic pulmonary disease.This possibility was, how- ever, not tested clinically.We decided therefore to investigate the influence of reserpine on pul- monary hypertension in a group of patients with chronic pulmonary disease.METHOD Cardiac catheterization was performed on a group of 17 patients with pulmonary disease.There were 10 suffering with pulmonary tuberculosis at different stages, mostly fibro-caseous with cavities, 6 with silicosis (all stage 3), and one with successive embolization of the pulmonary artery (Table I).The catheterization was done in the morning without pre-medication.After insertion of the catheter into the pulmonary trunk, a Cournand needle was introduced into the femoral artery under local anwsthesia.The zero level was adjusted to 10 cm.above the table on which the patient was lying.Subsequently a reading of the pressure in the pulmonary artery was taken (using an Elema electromanometer): the pulse rate and brachial artery pressure (by auscultation) were recorded at 5-minute intervals for 30-40 minutes.The mean brachial pressure was determined by adding one-third of the pressure amplitude to the diastolic pressure.At the end of the rest period the oxygen consumption was estimated.The expired air was collected in a Douglas bag for 5 minutes and analysed by a Zeiss interferometer.Blood specimens from the pulmonary artery and the femoral artery were withdrawn 10 and 30 and, in some instances, 40 minutes after the rest period.The oxygen saturation of the blood was determined by a Brinkman hmmoreflectometer.*The hemoglobin content was determined photometrically.The cardiac output was calculated according to Fick's principle.The pulmonary capillary venous pressure was determined at the onset and at the end of the period.Subsequently 1-2 mg.serpasil (Ciba) diluted in 10 ml.saline were injected into the trunk of the pulmonary artery or the right ventricle during two minutes.