Objective: The Small Parts Test Fixture (SPTF) (16 CFR 1501) was developed from cadavers of young children and foreign body (FB) data. Recent FB studies reveal that the SPTF misses outliers. Computerized tomography (CT) provides detailed dimensional data for young children. Our null hypothesis is that the SPTF (31.75 mm) is smaller than relevant portions of the aerodigestive tract.
Methods: A 3-year retrospective review (2011-2014) of head/neck CT data for infants and children (N = 106) aged 6 months to 6 years was completed. Six measurements (mm) were recorded: 1) maxillary incisors to posterior edge of hard palate (MI/HP); 2) posterior edge of hard palate to first cervical (C1) vertebra (HP/C1); 3) soft palate to posterior pharyngeal wall; and 4) interpalatine tonsillar distance; 5, 6) larynx diameter, and width. Two ratios were calculated: 1) ratio of lengths (hard palate to soft palate), and 2) laryngeal dimensional ratio.
Results: A linear trend of increasing dimensions with increased age was noted. The length measured MI/HP best correlates with known data of potential FBs causing injury or death. This MI/HP length can range from 33.8 to 45.8 mm for all children younger than 3 years of age and exceeds the SPTF diameter (31.75 mm). There were no statistical anatomical differences by gender in any of the age groups.
Conclusion: Computed tomography measurements appear larger than SPTF values developed from cadavers. These CT data support enlargement of the SPTF to enhance safety for choking hazards in children.
Level of evidence: 4 Laryngoscope, 129:1468-1476, 2019.
Keywords: Choking; Small Parts Test Fixture; aspiration; infants and children; larynx.
© 2018 The American Laryngological, Rhinological and Otological Society, Inc.