Proposal of Protocol for Forensic Histopathological Analysis of the Airways of Charred Bodies

Abstract

Determining the cause of death in autopsies of carbonized victims is challenging due to structural changes caused by fire. Essentially, the goal is to ascertain whether the fire affected the victim while alive or post-mortem. Additional tests, such as histological examination for soot in the airways, are often necessary to assist forensic pathologists in these cases. The presence of soot below the larynx indicates that the victim was breathing during the fire, suggesting vitality. However, during the fixation of tissues for histological examination, a reaction between formaldehyde and blood can produce a dark pigment similar to soot, especially in tissues undergoing post-mortem autolysis. This artifactitious pigment can be mistaken for soot during histological examination. To mitigate this issue, it is recommended to collect samples from strategic areas of the respiratory system during autopsy and fix them in 70% alcohol, which is an economical, simple, and reproducible method. This approach aims to prevent the formation of unwanted pigment, thereby enabling more precise forensic histopathological analysis. Based on a literature review and the Standard Operating Procedure manual of the Goiânia Forensic Institute, a standardized protocol has been developed for the histopathological analysis of airways in carbonized cadavers. This protocol aims to minimize the impact of artifactitious pigments, facilitating the interpretation of traces for more effective forensic analysis. Due to its cost-effectiveness, it is expected that this protocol can be routinely adopted and incorporated by Forensic Pathology services, enhancing accuracy in determining the cause of death in carbonized victims.