Does aminophylline improve nocturnal hypoxia in patients with chronic airflow obstruction?

The progression of pulmonary hypertension secondary to chronic airflow obstruction is thought to be related to the degree of nocturnal oxygen desaturation. We have studied 11 patients with severe smoking-related hypoxic chronic airflow obstruction (mean FEV1 0.67 L, mean arterial PO2 6.83 kPa) who showed less than 15% reversibility to 200 micrograms inhaled salbutamol delivered by a pressurised aerosol. There was no difference in nocturnal oxygen saturation when a control normal saline was compared to intravenous aminophylline given according to the BNF recommended dosages, despite theophylline levels of 9.20 and 9.03 micrograms ml-1 at the beginning and end of the infusion. There was no improvement overall in FEV1 and FVC by aminophylline, but in individual patients an improvement of FEV1 could be associated with an improvement in mean oxygen saturation. We conclude 1) that there is no benefit in the short-term administration of theophylline in chronic airflow obstruction, 2) that indiscriminate use of theophylline preparation in irreversible airways disease is not justified, but 3) that theophyllines may benefit individual patients.