title: Comparison of pulmonary autopsy findings of the rats drowned at surface and 50 ft depth.
abstract: BACKGROUND
  When a body is recovered from the water after a fatal SCUBA diving accident, it is useful to know if the diver was under pressure or not when he/she took his/her last breath, in order to determine the cause and manner of the death. If the victim was under pressure, the air remained in the lungs of the diver will be equal to the environmental pressure. If the body comes to the surface, the air in the lung will expand according to the Boyle's Gas Law and give mechanical damage to the surrounding tissues, due to decreases in environmental pressure. We designed an experimental study to see the difference in pulmonary autopsy findings of the rats that drowned under normobaric and hyperbaric conditions.
  
  
  METHODS
  Forty five male, 250-300 g, Sprague Downey adult rats were divided into three groups. Two groups of rats were drowned under normobaric conditions (Groups DS Group DSS) and the third group at 50 ft pressure (Group DD). The pulmonary autopsy findings of the groups were compared. In the light microscopy, the number of the microscopic fields (x10) containing at least one emphysematous area with longitudinal dimension greater than 300 micro m were compared among the groups.
  
  
  RESULTS
  The gross examination revealed a prominent swelling of the lungs in all rats in the Group DD, in comparison to that of the Groups DS and DSS. The number of the microscopic fields, which included at least one emphysematous area with longitudinal dimension greater than 300 micro m out of 150 fields from each of the groups DS, DSS and DD, were 88, 101 and 115 respectively. The difference between the group DS and DD was found to be statistically significant.
  
  
  CONCLUSIONS
  We conclude that in investigating the fatal diving accidents, pulmonary autopsy findings give valuable information whether the death occurred at the surface or at the depth.
authors.affiliation: Istanbul University, Istanbul Faculty of Medicine, Department of Underwater and Hyperbaric Medicine, 34093 Capa-Istanbul, Turkey. akin@toklu.net
authors.forename: Akin Savas
authors.initials: AS
authors.lastname: Toklu
authors.forename: Nevzat
authors.initials: N
authors.lastname: Alkan
authors.forename: Aydin
authors.initials: A
authors.lastname: Gürel
authors.forename: Maide
authors.initials: M
authors.lastname: Cimsit
authors.forename: Damla
authors.initials: D
authors.lastname: Haktanir
authors.forename: Sefika
authors.initials: S
authors.lastname: Körpinar
authors.forename: Sevim
authors.initials: S
authors.lastname: Purisa
mesh_terms: D000818:Animals; D004242:Diving / Q000009:adverse effects*; D004332:Drowning / Q000473:pathology*; D004804:Eosinophils / Q000473:pathology; D004912:Erythrocytes / Q000473:pathology; D049429:Forensic Pathology; D008168:Lung / Q000473:pathology*; D008297:Male; D008853:Microscopy; D011656:Pulmonary Emphysema / Q000473:pathology; D051381:Rats; D017207:Rats, Sprague-Dawley