Do Pacifiers Protect From Sudden Infant Death Syndrome (SIDS) Through an Increase in Upper Airway Patency?

Sudden infant death syndrome (SIDS) is the leading cause of death among infants between 1 month and 1 year of age in the developed world. SIDS continues to be a phenomenon of unknown cause. The best approach to for prevention in high risk infants is unclear. Several substantial lines of evidence indicate that pacifiers have a protective effect on the incidence of SIDS. These studies were significantly powered and the results were consistent world-wide. The explanation for the protective effects of pacifiers on SIDS prevalence is unclear. A recent case report from New Zealand showed by means of nasopharyngeal films of a baby with and without a pacifier the possibility that sucking on a pacifier is associated with a forward movement of the tongue with enlargement of the upper airways' cross sectional area. Indeed, this hypothesis was originally postulated 30 years ago by Cozzi et al.

Working hypothesis and aims: Our hypothesis is that since the upper respiratory tract is that portion of the airway that imposes the greatest resistance to ventilation, sucking on a pacifier results in upper airway dilatation, thus greatly reducing upper airway obstruction and improving ventilation at a stage when infants are virtually obligate nasal breathers. It should be stressed that airway resistance is proportional to the 3rd power of the radius of the airway, thus even a relatively small increase in airway diameter may have a profound effect on airway resistance and respiratory mechanical work of breathing! In young infants and those with underdeveloped respiratory center drive, this decrease in the work of breathing could certainly be sufficient to minimize the risk of SIDS as described above.Thus, the aim of this study is to demonstrate the effect of sucking on a pacifier on upper airway patency.