sir.—Intermittent bradycardia, a common problem in preterm infants, develops in approximately 25% of infants of less than 32 weeks' gestation.1 The causes vary from life-threatening conditions, such as septicemia, intracranial injuries, and metabolic disturbances, to relatively benign ones, such as idiopathic apnea and bradycardia of prematurity.2
Recently, we treated an infant who was born in an uncomplicated delivery after 30 weeks' gestation, weighing 1200 g. Apgar scores at one and five minutes were 8 and 9, respectively. At the age of 96 hours, the infant began having attacks of bradycardia. Prior to this incident, he had been receiving phototherapy for indirect hyperbilirubinemia.
The evaluation included a determination of serum levels of glucose, calcium, and electrolytes; a determination of arterial blood gases; a sepsis work-up; and an imaging of the brain cavities to rule out ventricular hemorrhage. All test results were negative or normal, and theophylline therapy was