Use of the histopathology in the differential diagnosis of drowning in fresh and salty water: an experimental model establishment in rats

PURPOSE: To develop a method of differential diagnosis to drowning, due to analysis of the alveolar macrophages quantitative, in rats submitted to induced drowning in fresh water and salty water. METHODS: Were used 15 male adult rats Wistar EPM-1, weight 360g (SD=21,3), randomized in three groups: G1- Control; G2- Fresh water; G3- Salty water, each one with n=5. The animals have been anesthetized and tracheostomized to insert a cannula inside the trachea, for drowning induction. The lungs have been removed, weighed, prepared for histology and colored by immunohistochemistry. The macrophages have been counted in both lungs (right and left) of each animal. The statistical test used was ANOVA (SPSS.10) with pG2>G1 with p=0,0001 in each comparison. The weight of lungs of G3 and G2 was higher than G1, with p>0,0001, however G3 and G2 do not possess difference statistics in the weight of lungs. CONCLUSION: The developed diagnostic method was efficient in rats. The results, if expanded, will be able to assist the Forensic Pathology for technique of low cost and high trustworthiness