Hyposphagma, positional asphyxia, and acute intoxication with psychoactive substances.

Hyposphagma or subconjunctival hemorrhage is extensive confluent bleeding located between the conjunctiva and episclera. It can develop after trauma or the Valsalva maneuver and hemorrhagic diathesis and vascular diseases, hypertension, arteriosclerosis, and diabetes are the predisposing causes. It may also appear as part of the so-called congestion syndrome of the face and neck in crush or mechanical asphyxia and ligature strangulation, as well as in head-down positional asphyxia. We present two cases of heavily intoxicated individuals who were both, at the time of death, in the position with their trunks bent at the waist over their thighs and their heads down between the legs. They both had severe facial congestion with pronounced hyposphagma. The formation of extensive subconjunctival bleeding or hyposphagma resulted in hemodynamic dysregulation, a consequence of the head-down position, with a decreased venous return of blood to the heart. Since it requires preserved circulation, this finding cannot be considered solely as a mere postmortem phenomenon. Thus, in the presented cases, and especially in other cases where the blood level of psychoactive substances alone may be insufficient to explain the death, positional asphyxia, including the head-down position, could be considered a contributing cause. In such cases, hyposphagma could prove to be a valuable marker of positional asphyxia.