Differentiation at necropsy between in vivo gas embolism and putrefaction using a gas score. (June 2016)

• Record Type: Journal Article
• Authors: Bernaldo de Quirós, Yara; Saavedra, Pedro; Møllerløkken, Andreas; Brubakk, Alf O.; Jørgensen, Arve; González-Díaz, Oscar; Martín-Barrasa, Jose L.; Fernández, Antonio
• Is Part Of: Research in veterinary science. Volume 106(2016)
• Page Start: 48
• Page End: 55
• Publication Date: 2016-06
• Subjects: Putrefaction -- Gas embolism -- Decompression -- Gas bubbles -- Venous gas index -- Stranded marine mammals; Veterinary medicine -- Periodicals; Veterinary Medicine -- Periodicals; Médecine vétérinaire -- Périodiques; Médecine vétérinaire -- Recherche -- Périodiques; Diergeneeskunde; 636.089
• DOI: 10.1016/j.rvsc.2016.03.007
• Languages: English
• ISSNs: 0034-5288

Abstract

Abstract: Gas bubble lesions consistent with decompression sickness in marine mammals were described for the first time in beaked whales stranded in temporal and spatial association with military exercises. Putrefaction gas is a post-mortem artifact, which hinders the interpretation of gas found at necropsy. Gas analyses have been proven to help differentiating putrefaction gases from gases formed after hyperbaric exposures. Unfortunately, chemical analysis cannot always be performed. Post-mortem computed tomography is used to study gas collections, but many different logistical obstacles and obvious challenges, like the size of the animal or the transport of the animal from the stranding location to the scanner, limit its use in stranded marine mammals. In this study, we tested the diagnostic value of an index-based method for characterizing the amount and topography of gas found grossly during necropsies. For this purpose, putrefaction gases, intravenously infused atmospheric air, and gases produced by decompression were evaluated at necropsy with increased post-mortem time in New Zealand White Rabbits using a gas score index. Statistical differences ( P < 0.001) were found between the three experimental models immediately after death. Differences in gas score between in vivo gas embolism and putrefaction gases were found significant ( P < 0.05) throughout the 67 h post-mortem. The gas score-index is a new and simple method that can be used by all stranding networks, which has been shown through this study to be a valid diagnostic tool to distinguish between fatal decompression, iatrogenic air embolism and putrefaction gases at autopsies. Highlights: We test a new method to characterize the amount of gas in marine mammal carcasses. The method was validated using New Zealand White Rabbits as animal model. The gas score method differentiates putrefaction gases from other gases. The highest gas scores were found in compressed and decompressed rabbits. It is a new, low cost, and easy method that can be used by all stranding networks.