Related Experiment Video
Updated: Jul 7, 2026
Modeling Encephalopathy of Prematurity Using Prenatal Hypoxia-ischemia with Intra-amniotic Lipopolysaccharide in Rats
Published on: November 20, 2015
Cardiorespiratory development in extremely preterm infants: vulnerability to infection and persistence of events
A O Hofstetter1, L Legnevall, E Herlenius
1Department of Woman and Child Health, Karolinska Institutet, Stockholm, Sweden.
Insights
Extremely preterm infants often experience cardiorespiratory events, which persist beyond term-equivalent age. Infection significantly worsens these events, highlighting the need for continued infant monitoring post-hospitalization.
Area of Science:
- Neonatal physiology
- Cardiorespiratory development
- Preterm infant care
Background:
- Extremely preterm infants frequently experience cardiorespiratory issues like apnoea, bradycardia, and hypoxemia.
- Limited longitudinal data exists on cardiorespiratory development in this vulnerable population.
Purpose of the Study:
- To characterize early, age-dependent changes in cardiorespiratory function in extremely preterm infants.
- To investigate the influence of disease, postnatal insults, and interventions on cardiorespiratory activity.
Main Methods:
- Prospective study of 33 infants (23-28 weeks gestational age).
- Weekly cardiorespiratory monitoring from birth to >45 weeks postconceptional age (PCA).
- Utilized impedance pneumography, ECG, and pulse oximetry to assess cardiorespiratory activity and events.
Main Results:
- Analyzed 338 recordings (3236 hours).
- Heart rate decreased, and O2 saturation improved with age; respiratory rate remained stable.
- 5973 cardiorespiratory events occurred, decreasing with age but remaining frequent at discharge (mean PCA 38.3 weeks).
- Infection significantly increased apnoea/hypopnoea and hypoxemia.
Conclusions:
- Cardiorespiratory events persist beyond term-equivalent age in extremely preterm infants.
- Infection substantially impacts cardiorespiratory function.
- Close post-hospitalization surveillance is critical for these infants.
Objective:
Apnoea, bradycardia and hypoxemia occur frequently in extremely preterm infants, yet there is little longitudinal data describing cardiorespiratory development in these infants. This prospective study characterized early age-dependent changes in cardiorespiratory function and determined how activity is affected by factors such as underlying disease, postnatal insults and therapeutic interventions.
Patients And Methods:
Thirty-three infants born between 23 and 28 weeks gestational age (GA) were monitored weekly from birth to beyond term-equivalent age (i.e. 25-45 weeks postconceptional age, PCA). Baseline cardiorespiratory activity as well as apnoea/hypopnoea, bradycardia and hypoxemia events were examined using impedance pneumography, electrocardiography (ECG) and pulse oximetry, respectively.
Results:
Three hundred thirty-eight cardiorespiratory recordings lasting 3236 h were analysed. While the respiratory rate (RR) did not change during the early postnatal period, heart rate (HR) decreased and O2 saturation improved. There were 5973 total cardiorespiratory events, and their incidence decreased with advancing age. However, they still occurred frequently at term-equivalent age and after hospital discharge (mean PCA at discharge=38.3+/-0.5 weeks). Moreover, infection significantly increased apnoea/hypopnoea and hypoxemia incidence.
Conclusion:
The persistence of cardiorespiratory events beyond term-equivalent age as well as the marked impact of infection on cardiorespiratory function indicate that close surveillance after hospitalization is of crucial importance in extremely preterm infants.
Related Concept Videos
01:29Respiratory Syncytial Virus Disease
01:17Pulmonary Cycle: Exhalation
01:10Atelectasis II: Pathophysiology
01:21Acute Respiratory Failure-II
The underlying physiological abnormalities that contribute to hypoxemic respiratory failure include:
01:29Pneumonia II: Pathophysiology
01:30Pneumonia III: Complications and Assessment