Forty-one preterm and fullterm infants (26.5-40.5 weeks gestational age and 31.5-50 weeks postconceptional age) free from neurologic and cardiopulmonary disease at the time of testing underwent a standardized esophageal dilatation test (EDT) during polygraphically controlled REM sleep. RR interval and total duration of the respiratory cycle (TTOT) were measured (1) during the 60 s preceding the EDT, i.e. mean control RR and mean control TTOT; (2) during EDT. Percent RR (%RR) was defined as the longest RR interval in milliseconds during EDT divided by mean control RR in milliseconds multiplied by 100, and percent TTOT (%TTOT) as the longest TTOT in seconds during EDT divided by mean control TTOT in seconds multiplied by 100. EDT provoked prolongation of both RR interval and TTOT. %RR decreased significantly with advancing gestational age (p less than 0.003), and %TTOT with advancing postconceptional age (p less than 0.003), indicating that both cardiac and respiratory responses to an EDT challenge are blunted with maturation.
View details for Web of Science ID A1990EE37100001
View details for PubMedID 2271714