© Science Museum / Science & Society Picture Library
A battery operated defibrillator, type 180c, with type 182 rechargeable power pack and paddles, made by Cardiac Recorders Ltd, London. If the heart stops, blood ceases to circulate around the body, meaning that within minutes, cells and tisues begin to die. This has particularly serious consequences in the brain, which can be irreversibly damaged if starved of oxygen for more than a few minutes. A defibrillator is designed to shock an arrested, or fibrillating, heart back into its regular beating. The paddles, which contain electrodes, are placed on the chest, and a burst of electricity is pased through them.