Respiratory patterns and risk of sudden unexpected death in infancy.

The overnight respiratory patterns of 25 infants at high risk and 42 infants at low risk of sudden unexpected death were studied during the first 6 months of life. 'Risk' was determined using the birth scoring criteria of Carpenter and Emery. Recordings were made at home using a twin-channel radar chest movement detector which was designed to avoid the need for contact with the infant. The recordings were analysed for respiratory frequency, total duration of apnoea, periodic breathing, duration of regular breathing, and amount of body movement. The high risk group of infants showed respiratory frequencies that were significantly higher than those of the low risk group. None of the other parameters showed significant differences between the groups. These findings do not support the widespread use of home apnoea monitors for infants.