Physical Models: Organ Models for Primary Blast

Abstract

With primary blast, when a shock wave hits the body, some of the energy is reflected and some absorbed by the body. As tissue within the body possesses both elastic and viscous properties (as well as some organs being multi-phasic in nature), their reactions to blast loading is complicated and difficult to predict. Different parts of the body, specifically organs, react differently to impulsive loading. This is due to a combination of their unique structure, which responds in a certain way to a mechanical stimulus, as well as the unique stress-strain state experienced in that part of the body, due to a given blast wave profile and the support conditions of that organ. This can lead to local injury development within a given organ resulting in consequences to the system as a whole (e.g. inflammation) or with damage mechanisms being interwoven and superposing. Multiple injury sites generate increased burden on the system leading to added complications in their treatment. Although in-vivo blast models continue to dominate the existing literature, these models tend to analyse whole body responses and sometimes fail to identify physical injury at the tissue level. Isolated organ experiments, termed ex-vivo models, maintain the architecture and functionality of the tissue for a short period of time and constitute a close representation of the in-vivo state [1]. This section focusses on the work assessing primary blast evaluation of the body at an organ level.