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Updated: Apr 17, 2026
Non-invasive Optical Measurement of Cerebral Metabolism and Hemodynamics in Infants
Published on: March 14, 2013
Preterm Infants Exhibit Greater Variability in Cerebrovascular Control than Term Infants
Karinna L Fyfe1,2, Alexsandria Odoi1, Stephanie R Yiallourou1,2
1The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Victoria, Australia.
Insights
Preterm infants show more variable cerebrovascular responses when sleeping prone, suggesting immature control that may increase their risk for sudden infant death syndrome (SIDS). This highlights differences in prone sleeping effects between preterm and term infants.
Area of Science:
- Neonatal physiology
- Cardiovascular regulation
- Sudden Infant Death Syndrome (SIDS) research
Background:
- Sudden infant death syndrome (SIDS) is a leading cause of infant mortality, with preterm infants facing a higher risk.
- Prone sleeping, a major SIDS risk factor, has been shown to affect cerebrovascular control in term infants.
Purpose of the Study:
- To investigate and compare cerebrovascular control in preterm versus term infants in prone and supine sleeping positions.
- To test the hypothesis that preterm infants have reduced cerebrovascular control in the prone position.
Main Methods:
- Polysomnography was conducted on 35 preterm and 17 term infants at multiple postterm ages.
- Infants underwent head-up tilts (HUT) in both prone and supine positions to challenge cardiovascular responses.
- Cerebral tissue oxygenation index (TOI) and mean arterial pressure (MAP) were continuously monitored.
Main Results:
- Prone sleeping led to increased cerebral tissue oxygenation index (TOI) following head-up tilts, unlike the supine position.
- While overall response patterns to HUT were similar between preterm and term infants, preterm infants exhibited significantly greater variability.
- This variability in response suggests an immature cerebrovascular control in preterm infants.
Conclusions:
- Cerebrovascular control mechanisms differ between prone and supine sleeping positions in preterm infants.
- The greater variability in responses among preterm infants indicates persistent immaturity in their cerebrovascular control.
- This immaturity may be a contributing factor to the elevated risk of sudden infant death syndrome (SIDS) in preterm infants.
Study Objectives:
Sudden infant death syndrome (SIDS) remains an important cause of infant death, particularly among infants born preterm. Prone sleeping is the major risk factor for SIDS and this has recently been shown to alter cerebrovascular control in term infants. As preterm infants are at greater risk for SIDS than those born at term, we hypothesized that their cerebrovascular control in the prone position would be reduced compared to term infants.
Patients Or Participants:
There were 35 preterm (mean gestation 31.2 ± 0.4 w) and 17 term (mean gestation 40.1 ± 0.3 w) infants.
Design:
Infants underwent daytime polysomnography at 2-4 w, 2-3 mo, and 5-6 mo postterm age. Infants slept both prone and supine and were presented with cardiovascular challenges in the form of 15° head-up tilts (HUT).
Measurements And Results:
Cerebral tissue oxygenation index (TOI) was recorded using near-infrared spectroscopy (NIRO-200 spectrophotometer, Hamamatsu Photonics KK, Japan) and mean arterial pressure (MAP) was recorded using a Finometer cuff (Finapres Medical Systems, Amsterdam, The Netherlands). In the prone position TOI increased following the HUT (P < 0.05), whereas no change was seen in the supine position. The overall pattern of response was similar in both groups, but more variable in preterm than term infants (P < 0.05).
Conclusions:
Cerebrovascular control differs between the prone and supine positions in preterm infants. Although overall the responses to head-up tilts were similar between term and preterm infants, greater variability of responses in preterm infants suggests persisting immaturity of their cerebrovascular control in the first year of life, which may contribute to their increased risk of sudden infant death syndrome.
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