Creating an optimal observational sleep stage classification system for very and extremely preterm infants.

Area of Science:

• Neonatal neuroscience
• Developmental pediatrics
• Sleep medicine

Background:

• Sleep is crucial for neuronal survival and fetal brain development.
• Neonatal intensive care unit (NICU) environments disrupt preterm infants' sleep-wake patterns.
• Validated behavioral sleep classification scales for preterm infants are lacking.

Purpose of the Study:

• To develop and validate a user-friendly visual system for classifying sleep stages in preterm infants.
• To establish a reliable tool for assessing sleep in preterm infants aged 25-37 weeks gestational age.

Main Methods:

• The Behavioral Sleep stage classification for Preterm Infants (BeSSPI) system was developed.
• BeSSPI utilizes seven observable items: eye movements, body movements, facial movements, vocalizations, heart rate, respiratory pattern, and activity level.
• Four sleep-wake stages were defined: active sleep (AS), quiet sleep (QS), intermediate sleep (IS), and wake (W).

Main Results:

• The study observed 69 preterm infants, totaling 10,922 minutes of behavioral data.
• Sleep stage distribution included 38.83% AS, 26.16% QS, 26.29% IS, and 8.72% W.
• The BeSSPI achieved a high interrater agreement (κ = 0.80) and satisfactory construct, content, face, and expert validity.

Conclusions:

• A simple, reliable, and valid visual method for assessing preterm infant sleep-wake stages was developed (BeSSPI).
• This novel instrument is applicable across all preterm age groups.
• BeSSPI is expected to enhance the rigor and reproducibility of future preterm infant sleep research.