Crash performance of a preemie positioning device to enhance infant safety in vehicles

Abstract

Premature or low-birthweight babies, when placed in a regular child safety seat (CSS), are at an increased risk of oxygen desaturation, apnoea and/or bradycardia. Oxygen desaturation is generally avoidable by ensuring proper airway management through appropriate positioning in the CSS. Often, when a low-birthweight infant is placed in a CSS it is in a fairly upright position and leaves the child prone to neck flexion which is undesirable as airway compromise might occur. A preemie positioning device (PPD) was developed to help address this issue. The PPD was developed based on material and neck positioning parametric studies which resulted in optimal neck positions for the configurations investigated. In an effort to examine the PPD effectiveness as an enhanced restraint device for low-birthweight children, a numerical model consisting of a regular CSS with the PPD and a novel anthropomorphic testing device (ATD) representing a small infant weighing less than 5 lbf was developed. Numerical simulations, considering frontal and side crash conditions, were completed using LS-DYNA. The frontal and side crash conditions were based upon existing and proposed federal motor vehicle safety standards (FMVSS) testing protocols. The PPD's performance was based on the ability to maintain acceptable neck angle, head accelerations, neck joint forces, and head injury criterion (HIC) values. An improved response in neck angle, head acceleration, HIC values, and neck forces was observed when the PPD was present with a slight increase in peak neck force when measured at the lower neck joint. For some configurations, peak upper and middle neck forces were reduced by up to 30% and peak head accelerations by up to 10%. Additionally, for the majority of crash metrics considered, consistent performance was noted between the two restraint configurations.