An evaluation of theophylline for idiopathic apnea of infancy.

19 infants admitted with a diagnosis of infantile apnea who were found to have periodic breathing were given oral theophylline to determine its effect. They were studied at a mean age of 7.1 weeks (1-16.4 week). Each infant was studied during two naps, immediately before and 7 days following the institution of theophylline therapy, which averaged 2.8 h in duration during which electro-oculograms, end-tidal CO2, heart rate, impedance respirations, and transcutaneous pO2 (tcpO2) were continuously monitored. Theophylline therapy (mean dose 2.3 mg/kg q. 6 h) was associated with a significant reduction of apnea attack rates in both REM and non-REM sleep. Periodic breathing and the number of minutes per hour of sleep during which the TC pO2 was between 40-50 mm Hg in non-REM sleep also decreased. There was no significant reduction in the number of obstructive apneas, the number of bradycardias with apnea, nor the largest single fall in tcpO2. Theophylline can significantly reduce central apnea and periodicity in the age group studied, but the long-term effects of such therapy require further assessment.