Positional asphyxia and work - related fatality: case report and review of literature

After attending this presentation attendees will understand the importance of the reconstruction of an unusual, fatal occupational accident by a detailed workplace investigation, combined with the evaluation of circumstantial data, and most of all, autopsy findings. The European Statistics of Accidents at Work project defines "fatal accidents at work" as a work related death of the victim within a year after the date of the accident. However the majority of these deaths occur either immediately at the time of the accident, or within a few days or a few weeks after the accident. This presentation will impact the forensic science community by emphasizing how scene investigation, forensic autopsy and toxicological analyses play a key role in the reconstruction of the dynamics involved in the occupational event, allowing the identification of any legal responsibilities of the worker or the employers. A 42-years-old man began working on his farmland in the morning; later in the afternoon he was found unresponsive with upper part of body (head and upper limbs) stuck in the upper and largest aperture (diameter cm 40) of an atomizer of a high-volume sprayer tank, with legs dangling. The other three smaller apertures (diameters cm 15, cm 15, cm 25, respectively) were covered by airtight screw caps. After the body was removed from the tank aperture, resuscitation attempts were unsuccessful and the death was pronounced on site. The inspection of the tank’s interior revealed a few blood traces and a small quantity of whitish liquid that was submitted to the toxicology laboratory. The external examination of the body revealed discontinuous bruises and abrasions on skin soft tissues around the shoulders, some of which were located along the body circumference between the abdominal and thoracic regions. They were characterized by morphological features of the tank aperture in which the victim's body was trapped. The hypostasis were cyanotic and dark colored. There were several petechial hemorrhages on the anterior neck, facial skin, in the eye, and on the superior part of the chest. During the autopsy, the gross and histological examinations of viscera showed petechiae on serosa, marked venous congestion of organs, and pulmonary edema. Cardiovascular and respiratory pathologies as well as other patho-anatomical diseases were excluded, and furuther confirmed by a review of medical records. The toxicological analyses of body fluids were negative for alcohol, drugs or hazardous substances. Chemicals or hazardous substances were not found in the samples of the tank’s liquid contents. The cause of the death was related to positional asphyxia by immobilization of body and by mechanical impediment to adequate respiratory movements for an extended time. Moreover, due to the victim’s position, the upper part of respiratory tract was trapped in the confined airtight tank space with deprivation of oxygen. The final determination of the cause of death was essentially based on three criteria: body position obstructing normal breathable air exchange, impossibility to move to another position, and exclusion of other causes of natural or violent death. The information provided by inspectors and Police Officers who performed the workplace investigation revealed that the victim was using the atomizer for spraying water on vegetables being cultivated in his own field. The farmer had climbed upon a small, wooden step stool (found closest to atomizer) to reach the upper aperture of the tank for cleaning procedures. The inspection of the machine did not indicate any malfunctions. Considering all the evidence, the manner of death was certified to be an accident at work. The uniqueness of the reported case is confirmed by reviewing the literature.