[Lung functions and blood levels after parenteral administration of theophylline-ethylenediamine (author's transl)].

Theophylline-ethylenediamine (Euphyllin) was given to 45 patients with various degrees of obstructive airway disease, eight receiving 0.24 g i.v., 22 an infusion of 0.72 g over four hours, and 15 an i.m. injection of 0.36 g. Lung-functions, pulmonary artery pressures and - in several cases - theophylline blood levels were measured. The specific bronchial flow resistance was reduced in all patients, by 30% on average, without any significant correlation to the blood level. Ventilation rose by about 15%, while arterial pCO2 and mean pulmonary arterial pressure fell significantly. No effect on respiratory failure to the existing pulmonary hypertension was demonstrated in three patients with decompensated chronic cor pulmonale with 0.72 g by a four-hour infusion. After i.v. or i.m. injection of the same dose theophylline blood levels were at the lower range of effective concentration, which is thought to lie around 5-15 microgram/ml plasma. The results indicate that a specially effective and lasting therapy can be achieved with an initial dose of 0.24 g Euphyllin followed by continuous infusion of 0.72 g over 6-8 hours.