Death by overlaying and wedging - A 15-year retrospective study

Overlaying, the accidental death by smothering caused by a larger individua l sleeping on top of an infant, is a cause of death that has been documente d for centuries. The hazard of death has been reported to be greater in inf ants less than 5 months of age but may occur in children up to the age of 2 years. When an adult or older child rolls on top of an infant, mechanical asphyxia results. The face may be pressed into the mattress or into the bod y of the sleeping adult or older child. The infant's air may be expressed, and he or she is unable to cry due to pressure on the thorax and the inabil ity to inhale. Some pathologists and investigators believe that the victims of overlaying have no pertinent physical findings at autopsy and that any injury is indicative of inflicted trauma. Others believe that one may see c ontusions and abrasions from overlaying in and of itself. Wedging is anothe r form of accidental mechanical asphyxia that may have negative autopsy fin dings. The prevalence of bruising, contusions, or facial and ocular petechi ae is not clear. The author reviewed all pediatric forensic cases referred for autopsy to th e Forensic Section of the Medical University of South Carolina/Medical Exam iners' Office over the past 15 years, from 1985 to 1999. Of these, all case s of overlaying, cases listed as undetermined sudden infant death syndrome versus overlaying, and wedging were included. The cases were analyzed as to victims' age, sex, race, location/bedding, bed-sharer, and whether the bed -sharer was known to have ingested drugs or alcohol before sleep. Postmorte m physical findings were also reviewed, particularly for documentation of c ontusions, abrasions, or facial or ocular petechiae. By clarifying not only the victim, bed-sharer, and scenario but also the presence or absence of p hysical findings in cases of overlaying, wedging, and other accidental asph yxia, we can better categorize these cases.