Related Experiment Video
Updated: Sep 30, 2026
Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
Duration of ductal shunting in healthy preterm infants: an echocardiographic color flow Doppler study
M D Reller1, M L Ziegler, M J Rice
1Department of Pediatrics, Oregon Health Sciences University, Portland 97201.
Insights
Healthy preterm infants without respiratory distress show normal closure of the ductus arteriosus. Prematurity does not prolong physiologic ductal shunting in this population.
Area of Science:
- Neonatology
- Pediatric Cardiology
- Physiology
Background:
- The ductus arteriosus is a fetal blood vessel that normally closes shortly after birth.
- Premature infants may experience delayed closure of the ductus arteriosus, potentially leading to complications.
- Understanding the timing of ductal closure in healthy preterm infants is crucial for clinical management.
Purpose of the Study:
- To assess the duration of ductal shunting in healthy preterm infants (30-37 weeks gestational age) without respiratory distress.
- To compare ductal closure rates between different gestational age groups of preterm infants and full-term controls.
Main Methods:
- Two-dimensional echocardiography and color flow Doppler were used to evaluate ductal flow in 36 preterm and 16 full-term infants.
- Infants were studied within 12 hours of birth and daily thereafter until functional closure of the ductus arteriosus was confirmed.
- Preterm infants were categorized into two groups based on gestational age: 30-33 weeks and 34-37 weeks.
Main Results:
- All infants, except one, demonstrated closure of the ductus arteriosus by day 4.
- Ductal closure rates were high by day 3 (81.3% to 87.5%) across all studied groups.
- No significant prolongation of physiologic ductal shunting was observed in preterm infants compared to full-term controls when respiratory distress was absent.
Conclusions:
- Prematurity, in the absence of respiratory distress syndrome, does not appear to prolong the initial duration of physiologic ductal shunting.
- Healthy preterm infants exhibit timely closure of the ductus arteriosus, similar to full-term infants.
- These findings suggest that routine monitoring for prolonged ductal shunting may not be necessary in healthy preterm infants without respiratory compromise.
Abstract:
The purpose of this investigation was to assess the duration of ductal shunting after birth in healthy preterm infants (30 to 37 weeks gestational age) without evidence of respiratory distress. Thirty-six infants were evaluated in the first 12 hours of life by means of two-dimensional echocardiography and color flow Doppler techniques, and then once daily until no ductal flow was detected (defined as functional closure). Preterm infants were subdivided into two groups by gestational age: group 1 = 30 to 33 weeks (n = 12); group 2 = 34 to 37 weeks (n = 24). Sixteen full-term infants (38 to 41 weeks) were similarly evaluated as control subjects (Group 3). One infant from each group had a closed ductus at the time of the first study (performed at a mean of 7.7 +/- 3.2 hours). Subsequent studies for the entire group were performed at a mean of 31.3 +/- 5.4 hours (day 2), 55.0 +/- 4.5 hours (day 3), and 80.3 +/- 6.1 hours (day 4). For the three groups, the rates of ductal closure ranged from 50.0% to 58.3% on day 2 and 81.3% to 87.5% on day 3. For the entire group, all but one infant had demonstrated closure of the ductus arteriosus by day 4. Within the range of gestational ages studied, we conclude that prematurity, in the absence of respiratory distress syndrome, does not prolong the initial duration of physiologic ductal shunting.
