A case of complex asphyxia sheds light on problems in the classification of asphyxias.

Death from positional asphyxia is often an accidental event occurring when the victim's body assumes a position which can compromise an effective respiration. Its diagnosis is usually not simple, because it needs to know the exact circumstance in which the body was found and the original positioning of all the body segments. In this case, a 41-year-old man with a history of opioid drugs abuse was found dead in a knee-chest position; the head was down on the floor with the face resting on a plastic bag. Pictures of the scene of death was taken while the body was still in its original position. At first, the main suspicion was that of a fatal overdose. Following the autopsy examination, completed by histological and toxicological examinations, the cause of death was determined as postural asphyxia secondary to intoxication by methadone, in the presence of ischemic heart disease. Some features, moreover, were typical of the death in head down position, and the prolonged knee-chest position was also associated with the obstruction of mouth and nose by the plastic bag, which may have contributed to the asphyxiation. These cases of "combined" asphyxia represent a challenge for the current classifications of asphyxia, which are very variable and not standardized, as we observe from a brief review of the literature. The elaboration of new systems of classification for asphyxias, which must be clear, simple and shareable, is necessary to avoid confusion in categorizing cases that present overlapping between several types of asphyxiation modalities.