Over two-thirds of sudden unexpected infant deaths classified as accidental suffocation were attributed to airway obstruction by soft bedding, according to research published in Pediatrics.

Baby in supine position FamVeld/Thinkstock

Alexa B. Erck Lambert, MPH, of DB Consulting Group in Silver Spring, Md., and her associates conducted an analysis of 1,812 cases of sudden unexpected infant death (SUID) in children aged 1 year or less included in a Centers for Disease Control and Prevention registry. Of those 1,812 SUID cases, 250 (14%) were classified as accidental suffocation.

Airway obstruction by soft bedding was by far the most common mechanism of accidental suffocation, contributing to death in 69% of cases. Overlay was attributed in 19% of cases and wedging was attributed in 12%. The median age for soft bedding, overlay, and wedging death was 3 months, 2 months, and 6 months, respectively. The majority of cases were male (55%), born after at least 37 weeks’ gestation (81%), non-Hispanic white or African American (74%), and insured by Medicaid (70%).

In deaths attributed to soft bedding, 49% occurred while the infant was in an adult bed, 92% occurred while the infant was in a nonsupine position, and 34% occurred while a blanket was obstructing the airway. While infants aged 5-11 months were twice as likely to have had a blanket obstructing their airway as infants aged 0-4 months (55% vs. 27%), younger infants were twice as likely to have had a pillow or couch cushion obstructing their airway (25% vs. 11%).

Of the 51 overlay deaths, 71% occurred in an adult’s bed, 51% were found nonsupine, and 41% were found in a bed with more than one adult. Most deaths were attributed to neck or chest compression, rather than nose or mouth obstruction. Of the 33 wedging deaths, 45% were sharing a sleep surface and 73% were in an adult bed; the most common objects the infant was wedged between were a mattress and wall.

“The safest place for infants to sleep is on their backs, on an unshared sleep surface, in a crib or bassinet in the caregivers’ room, and without soft bedding in their sleep area,” the investigators wrote. “Improving our understanding of the characteristics and risk factors ... of suffocation deaths by mechanism of airway obstruction can inform the development of more targeted strategies to prevent these injuries and deaths.”

The authors reported no potential conflicts of interest. Ms. Erck Lambert was supported by a contract her employer and the Centers for Disease Control and Prevention. Meghan Faulkner’s agency also received funds from the Centers for Disease Control and Prevention.

SOURCE: Erck Lambert AB et al. Pediatrics. 2019 Apr 22. doi: 10.1542/peds.2018-3408.