[Death by obstructive asphyxia: the pathophysiology of respiration and hemodynamics (author's transl)]

The pathophysiology of respiration and hemodynamics during the agonal period of death by obstructive asphyxia was investigated. Experiments were carried out on ten dogs that were strangulated by ligature (seven cases) or asphyxiated by occlusion of the intubation tube (three cases). The following parameters were registered: Blood pressure in the arteria femoralis and arteria pulmonalis, electrocardiogram, endotracheal pressure, respiratory frequency, electroencephalogram. These were the most important findings: (a) An excessive and distinctly biphasic hypertonic reaction takes place after strangulation by ligature whereas occlusion of the intubation tube results in a slight increase of arterial blood pressure. (b) After occlusion of the tube more than after strangulation the endotracheal pressure becomes deeply negative during the inspiration trials. (c) After cessation of respiration a distinct pulmonary arterial hypertension develops in both forms of obstructive asphyxia. (d) The paralysis of the respiratory center takes place after about 4 min at the same time when the circulatory breakdown develops. The final cardiac failure occurs after about 9-10 min. The dysregulation of respiration and hemodynamics in the agony of obstructive asphyxia can be differentiated from other shock models. This results in special morphological alterations of the lung tissue which have been described elsewhere.