[Influence of acute respiratory failure on plasma renin activity and plasma angiotensin II level in advanced chronic obstructive pulmonary disease and chronic cor pulmonale].

Plasma renin activity (PRA) and plasma angiotensin II (PAT II) level were determined with the method of radioimmunoassay in 55 patients with advanced chronic obstructive pulmonary disease (COPD) and chronic cor pulmonale (41 of them had respiratory failure) and 12 healthy aged persons. The results showed that PRA and PAT II levels were significantly elevated in the presence of such factors as severe hypoxia and hypercapnia (PaO2 less than or equal to 45 mmHg, mean 40 mmHg, PaCO2 greater than or equal to 65 mmHg), right heart failure, acidosis, hyponatremia and hypochloremia. It is shown that the prognosis would be poor when the patient's PRA level is significantly elevated.