Babies travelling in car seats should be provided with additional support to prevent blocking of their airway, research suggests.

A research team from The University of Auckland, Auckland Hospital and the New Zealand Cot Death Association found that breathing problems were significantly reduced when young infants were placed in a car safety seat with a foam insert in it, designed to help the infant’s head to lie upright in a natural position instead of slumping forward.

The research team have worked with Dunlop Foams to develop the foam insert which holds the infant’s body forward with a slot for the protruding back of the head. This allows the head to lie upright even when the baby falls asleep, keeping the baby’s airway open. The insert was designed to protect infants until they are about nine months old, when infants’ jaws become stable.

"Car seats are absolutely necessary for the safety of all small children, but the seat should be made as safe as possible for very young children," says Dr Shirley Tonkin of the NZ Cot Death Association. "We reported last year in the British Medical Journal that some healthy full term babies had severe stop breathing attacks while they were sleeping in their car seats. By using a foam insert that allows the infant’s head to sit upright, the airway is kept open and the baby is kept safe. A side benefit is that babies seem to sleep more comfortably, but babies should still not be left to sleep unattended."

"Babies are not shaped like little adults," says Professor Alistair Gunn of the University’s Departments of Physiology and Paediatrics. "Young babies have relatively much bigger heads than adults and they stick out behind the line of the back. At the same time they have very short necks so that their chins are almost on their chests, and their muscles are less well developed. Because standard infant car seats have flat backs, when an infant is properly strapped in place, the flat back of the seat pushes on the back of the head, which is bent forward, so that the chin is pressed against the chest. Because babies have very mobile jaws, the chin is easily pushed backward, with tongue inside it constricting the airway."

This study monitored healthy full-term babies for 30 minutes restrained in a car seat with the foam insert and 30 minutes without the insert. The infants were monitored for breathing and heart rate, nasal airflow and blood oxygen levels. The research found use of the insert reduced the number of breathing problems. The results are published in the medical journal Acta Paediatrica.

The Dunlop Foams Happi car seat inserts are available from Baby Factory and Para Rubber stores across New Zealand. The inserts are available in two styles, one for car "capsules" and one for car seats.