Forensic Engineering Evaluation of CO2 Re-Breathing in Infant Bedding Materials

Article Author(s): Michael Leshner, P.E. (NAFE 559F)

Volume: 29
Volume #: 2
Month: December 2012
Year: 2012

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A four-month-old infant suffocated in his sleep from positional asphyxia. The baby was found face down on a foam wedge pillow called a sleep positioner. The author was engaged to evaluate the sleep positioner product for its potential to cause carbon dioxide (CO2) re-breathing in infants. Prior research on this subject had already established a reliable method of simulating infant breathing and measurement of respiratory gas constituents using a mechanical breathing model. Guided by this research, a mechanical breathing model and gas sampling apparatus was coupled to a mannequin representing the child in this matter. The mannequin was placed in face-down and sidefacing positions on the sleep positioner product and twelve other surfaces, including a plain cotton sheet as the baseline. The sleep positioner product produced the highest (and most dangerous) level of CO2 re-breathing, more than three times the baseline level. Factors contributing to CO2 re-breathing are discussed.


Carbon dioxide, re-breathing, SIDS, Sudden Infant Death Syndrome