[Long-term (6 months) treatment of chronic bronchitis with respiratory insufficiency using almitrine dimesylate. Double-blind study versus placebo].

The purpose of this controlled, double-blind therapeutic trial in chronic bronchitis patients with hypoxia and normocapnia was to evaluate the beneficial effects of a 6-month treatment with almitrine bismesylate on dyspnoea and blood gases, as well as the clinical, spirometric and pulmonary haemodynamic acceptability of the drug. Patients were allotted at random to either almitrine bismesylate 100 mg/day in two divided doses (n = 10) or a placebo similarly administered (n = 9). On entering the trial, both groups had comparable clinical symptoms, lung function, blood gas values and pulmonary haemodynamic values. A significant (p = 0.014) reduction of dyspnoea was observed in the treatment group but not in the placebo group. A significant (p less than 0.05) improvement in PaO2 was noted after 3 and 6 months of treatment while PaCO2, initially normal, was not significantly modified. There were no significant changes in respiratory rate and external ventilation in either group, and the mean pulmonary arterial pressure remained unchanged in all patients. No significant variations were observed in the patients' weight, systemic arterial pressure, heart rate or signs of right ventricular failure. In conclusion, this trial in chronic bronchitis patients with hypoxia and normocapnia demonstrated sustained improvement in hypoxaemia and clinical symptoms during a 6-month treatment with almitrine bismesylate, without changes in pulmonary haemodynamic values.