Apnea monitor failure in infants with upper airway obstruction.

Obstruction of the upper airway in infants may be associated with continued respiratory efforts without air entering the lungs.1-4 Our clinical experience has led us to suspect that some apnea monitors in current use are unable to differentiate between these ineffective respiratory efforts and true breathing. To document this deficiency of apnea monitors, we examined the response of two types of apnea monitors to respiratory movements during upper airway obstruction. SUBJECTS AND METHODS Five healthy full-term infants were studied during the first three days of life, and two premature infants in stable condition (birth weight, 1.32 kg and 1.30 kg; gestational age, 32 weeks) were studied at 25 days of age when they no longer had apnea associated with bradycardia in the nursery.