Simple car seat insert to prevent upper airway narrowing in preterm infants : a pilot study

Premature infants often slouch the head forward when they fall asleep while restrained in car seats. This study investigates if a simple foam insert in the car seat that allows the infant's head to rest in a neutral position on the trunk would prevent narrowing of the upper airway and thus reduce oxygen desaturation in premature infants who are restrained in car seats. Seventeen preterm infants were evaluated in a car seat for newborns, with and without a foam insert that provided a slot for the back of the infant's head. Respiration timed inspiratory radiographs for assessment of upper airway dimensions were taken during quiet sleep in each position. Infants were monitored in each position for 30 minutes with continuous polygraphic recording of respiratory, cardiac and nasal airflow activity and pulse oximetry. Result showed that the insert in the car seat was associated with a larger upper airway space. This radiographic improvement was associated with a significant reduction in the frequency of episodes of oxygen desaturation, of bradycardia and of arousal. These results suggest the hypothesis that flexion of the head is a significant contributor to oxygen desaturation in premature infants who are restrained in car seats and that the mechanism is posterocephalic displacement of the mandible, leading to narrowing of the upper airway. When the insert was place in the car seat so that the head could be maintained in a neutral position on the trunk, the infants' upper airway size and vital signs were normalized.