What is Least common organ affected in blast injury is - and explain in detail?
Ans. is 'c' ie., Muscles * An explosion is a phenomenon resulting from sudden release of energy which is then dissipated by a blast wave, by translocation of objects, or by the generation of heat.* Injuries in explosion occur due to four factors:-1) Blast or shock wave# When an explosion occurs, the explosive material produces a large volume of gas and releases a large amount of energy. It produces a 'shock wave' which spread concentrically from the site of explosion.# The injuries depend on the enviornment in which blast occurs:-i) Air blast (most common):* Explosion occurs in air. There is barotrauma to airfilled hollow organs. Tympanic membrane (ear drum) is most sensitive and most commonly injured. Lung is the second organ to be injured and is the most commonly injured hollow organ and most common cause of life threatening injury.* Other parts injured are middle ear, cochlea, eyes, bowels, mesentery, omentum and brain. Homogenous solid organs like liver and muscles are usually not affected.ii) Under water blast (explosion under water):* Gastrointestinal tract is injured most commonly. Lungs are also injured.iii) Solid blast:* Explosive is detonated near a rigid/solid structure and wave of energy spreads through it. If people are in contact with that rigid structure, injuries take place.* The injuries are mostly skeletal; fracture of legs and vertebral column are more common. GIT damage is more common than lung.2) Flame or hot gases# Burns or burning of body may occur.3) Flying missiles (debris)# Flying pieces of explosive debris may be driven through air against the skin causing bruises, abrasions, lacerations, and ragged perforations.4) Anoxia# Various gases liberated during explosion may cause anoxia, e.g. carbon monoxide, nitrous oxide, nitric oxide, HCN and SO2