Abstract
Although asphyxial deaths often have very characteristic death scene features, the pathological diagnosis of asphyxia is often difficult as there are no pathognomonic findings at autopsy; i.e. features such as fluidity of the blood, congestion, oedema, engorgement of the right side of the heart and petechial haemorrhages are no longer considered diagnostic. For this reason, accurate evaluation of the death scene is required, with careful exclusion of injuries and underlying organic diseases that may have caused or contributed to death. Particular difficulties arise in infants and in the elderly. Classifying asphyxia by underlying pathophysiological processes as being due to failure in the supply, transfer, transport, uptake and utilization of oxygen provides a clearer indication of underlying mechanisms than categorizations based on circumstances.