Sequential 22-Hour Profiles of Breathing Patterns and Heart Rate in 110 Full-Term Infants During Their First 6 Months of Life

Abstract

Sequential recordings (total number 365, mean duration 22 h) of ECG and abdominal wall movement were obtained from 110 full-term infants up to 6 mo. of age. The longest pause in breathing movement per recording (maximum 21.6 s) decreased in duration over the first 2 wk of life (P < 0.005). Pauses > 18.0 s were not detected after 7 days. The spread of values for pauses .gtoreq. 3.6 s duration was widest during the first 2 wk, and their number decreased with age (P < 0.001). Periodic breathing, detected in 69 to 80% to infants in all age groups, showed decreasing trends with age in total duration and maximum length of episode (P < 0.005 for both). The spread of values was widest during the first 2 wk (range for total duration 0 to 4.7 h) and decreased with age. The mean respiratory rate during regular breathing decreased after 4 wk (P < 0.001). The spread of spread of values was widest during the first 2 wk and decreased with age. Birth weight was positively correlated with mean respiratory rate during the first 3 days of life (r = +0.64, P < 0.001). The mean heart rate during regular breathing increased during the first 15 days (P < 0.001) and then decreased after 4 wk (P < 0.001). Higher mean heart rates were found in male infants (P < 0.01).