RESUMEN
Artificial respiration has a dramatic history, made so by the latruistic aim behind the crude attempts of the technique to save lives. Without the aid of science, and beset by fear, witchcraft, and superstitions man began to look for the answer to his dilemma-how to revive a person who had stopped breathing. Then, with the aid of science, during the 17th century, these methods were improved, tested, and made comparatively more effectiveAt present there are two methods very popular in almost all English-speaking countries- the Sylvester methods and the Schafer method. In 1932, another technique of artificial respiration, the H.N. method was introduced. This method is a double-action technique wherein both the expiration and inspiration are forced by the operator. It claims the following advantages over the Schafer method: 1. The method makes use of both movements of the operator2. The H.N. method gives greater ventilation than the other first-aid methods, especially by the very effective inspiration induced by an arm-lifting movements3. The operation is less tiresome4. The H.N. method (arm raising only) can be applied more conveniently by the operator even while the victim is being transported on a stretcher5. The method causes no injury to the patient, not even to a pregnant woman. (Summary)