A New Reference Source for Postmortem Body Measurements and Organ Weights in Neonates and Infants: A Statistical Analysis Based on Sudden Death Classification (Part 2).

Reference charts for body and organ measurements of neonates and infants were derived from data on 900 investigations done by the Office of the Chief Coroner for Ontario. The statistical analyses in this new reference source addressed deficiencies in sources currently available to pathologists.The present study also considered whether organ weights differed based on the classification of infant deaths using the original definition of either sudden infant death syndrome (SIDS) or sudden unexplained death (SUDS) which considers cases occurring in an unsafe sleeping environment or under adverse socioeconomic conditions. Cases of SUDS for both sexes peaked in 5 to 16 weeks of age. The thymus in the SUDS/SIDS age groups less than 25 weeks weighed more than the control group. Adrenal weights in SUDS cases between 9 and 16 weeks weighed less than SIDS cases. This could mean that deaths in unsafe sleep environments are truly sudden in infants who may have a limited adrenal response to acute hypoxia but have been unaffected by preceding chronic stressors.