CARDIORESPIRATORY ASSOCIATIONS OF ACUTE BRONCHIDLITIS IN INFANCY

The occurrence of apnoea during acute viral bronchiolitis in infancy has not been documented in relation to age and maturity of the infant and stage of the illness. We have recorded respiratory movements (chest and abdomen) and heart rate over 24 hours in 27 infants with acute viral bronchiolitis. There were 20 full-term and 7 pre-term infants studied at a mean age of 10.5 weeks (range 2-20) and 10.3 weeks (range 6-17) respectively. Sequential studies of 10 infants during the coryzal, bronchiolitic and recovery stages of illness showed the changing pattern of events. Of 9 infants (2 pre-term) studied in the coryzal stage both the pre-term infants showed abnormalities - 1 prolonged central apnoea >20 seconds without bradycardia and the other apparent obstructive apnoea with bradycardia (80 bpm for 10 seconds). During the acute bronchiolitic stage, 5 of 18 infants (2 term, 3 pre-term) had central apnoea > 20 seconds associated with bradycardia in one pre-term infant. Apparent obstructive apnoea with bradycardia in 7 (4 term, 3 preterm). Of 14 infants in recovery, 1 term infant had prolonged central apnoea and 1 other ‘obstructive’ apnoea with bradycardia. Apnoea was most severe during the acute stage for both the group and individual infants studied sequentially. All those with significant central apnoea were aged less than 10 weeks, ‘obstructive’ apnoea was seen up to 13 weeks.