Positional Asphyxia: Remains Hard to Diagnose?

Abstract

Positional asphyxia is a type of asphyxia where the position of an individual compromises the ability to breathe. It is commonly caused by accidents due to alcohol or drug intoxication, diseases, and/or being in a confined space. In this study, the authors reviewed autopsy cases at their institute over the past 5 years where positional asphyxia is suspected as a contributing factor or cause of death. The autopsy cases (n=24) were divided into three groups: positional asphyxia was the cause of death (n=15); unknown cause of death but positional asphyxia was considered (n=4); and positional asphyxia was suspected to be a contributing factor (n=5). All cases of group A included postures that could interfere with breathing, but the typical jackknife or head-down postures were seen in approximately half of the cases; “classic signs of asphyxia” were also observed in approximately half of the cases. They shared features such as high blood alcohol concentration, therapeutic levels of drugs, various disease, minor head trauma, and morbid obesity; however, no definite diagnostic criteria have been established for forensic practice. Positional asphyxia is a form of mechanical asphyxia which must be differentiated from traumatic asphyxia. In addition to a complete autopsy, thorough laboratory tests and understanding of the circumstances of the case and the situation at the death scene are required for diagnosis. Special attention is required for the diagnosis of special types of positional asphyxia such as death during institutional restraint or prone restraint.