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A Concise History of the ECG: Difference between revisions
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[[Image:Luigi_Galvani_oil-painting.jpg| | [[Image:Luigi_Galvani_oil-painting.jpg|100px|frame|Italian Anatomist '''Luigi Galvani''']]Italian Anatomist '''Luigi Galvani''' notes that a dissected frog's leg twitches when touched with a metal scalpel. He had been studying the effects of electricity on animal tissues that summer. | ||
[[Image:Galvani_experiment.jpg| | [[Image:Galvani_experiment.jpg|100px|frame|Luigi Galvani's frog leg]]On 20th September 1786 he wrote "I had dissected and prepared a frog in the usual way and while I was attending to something else I laid it on a table on which stood an electrical machine at some distance from its conductor and separated from it by a considerable space. Now when one of the persons present touched accidentally and lightly the inner crural nerves of the frog with the point of a scalpel, all the muscles of the legs seemed to contract again and again as if they were affected by powerful cramps." | ||
He later showed that direct contact with the electrical generator or the ground through an electrical conductor would lead to a muscle contraction. Galvani also used brass hooks that attached to the frog's spinal cord and were suspended from an iron railing in a part of his garden. He noticed that the frogs' legs twitched during lightening storms and also when the weather was fine. He interperated these results in terms of "animal electricity" or the preservation in the animal of "nerveo-electrical fluid" similar to that of an electric eel. He later also showed that electrical stimulation of a frog's heart leads to cardiac muscular contraction. Galvani. De viribus Electritatis in motu musculari Commentarius. 1791 | He later showed that direct contact with the electrical generator or the ground through an electrical conductor would lead to a muscle contraction. Galvani also used brass hooks that attached to the frog's spinal cord and were suspended from an iron railing in a part of his garden. He noticed that the frogs' legs twitched during lightening storms and also when the weather was fine. He interperated these results in terms of "animal electricity" or the preservation in the animal of "nerveo-electrical fluid" similar to that of an electric eel. He later also showed that electrical stimulation of a frog's heart leads to cardiac muscular contraction. Galvani. De viribus Electritatis in motu musculari Commentarius. 1791 | ||
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'''1788''' Charles Kite wins the Silver Medal of the Humane Society (awarded at the first Prize Medal ceremony of the Society co-judged with the Medical Society of London) with an essay on the use of electricity in the diagnosis and resuscitation of persons apparently dead. This essay is often cited as the first record of cardiac defibrillation but the use of electricity suggested by Mr Kite is much different. For example, on describing a case of drowning from 1785 where resuscitation had been attempted with artificial respiration, warmth, tobacco, "volatiles thrown into the stomach, frictions, and various lesser stimuli" for nearly an hour, he then recalls the use of electricity. "Electricity was then applied, and shocks sent through in every possible direction; the muscles through which the fluid [electricity] passed were thrown into strong contractions." He concluded that electricity was a valuable tool that could determine whether or not a person, apparently dead, could be successfully resuscitated. Annual Report 1788: Humane Society, London. pp 225-244. Kite C. An Essay on the Recovery of the Apparently Dead. 1788: C. Dilly, London. | '''1788''' Charles Kite wins the Silver Medal of the Humane Society (awarded at the first Prize Medal ceremony of the Society co-judged with the Medical Society of London) with an essay on the use of electricity in the diagnosis and resuscitation of persons apparently dead. This essay is often cited as the first record of cardiac defibrillation but the use of electricity suggested by Mr Kite is much different. For example, on describing a case of drowning from 1785 where resuscitation had been attempted with artificial respiration, warmth, tobacco, "volatiles thrown into the stomach, frictions, and various lesser stimuli" for nearly an hour, he then recalls the use of electricity. "Electricity was then applied, and shocks sent through in every possible direction; the muscles through which the fluid [electricity] passed were thrown into strong contractions." He concluded that electricity was a valuable tool that could determine whether or not a person, apparently dead, could be successfully resuscitated. Annual Report 1788: Humane Society, London. pp 225-244. Kite C. An Essay on the Recovery of the Apparently Dead. 1788: C. Dilly, London. | ||
[[Image:Alessandro_Volta.jpg| | [[Image:Alessandro_Volta.jpg|100px|frame|Alessandro Volta]]'''1792''' Alessandro Volta, Italian Scientist and inventor, attempts to disprove Galvani's theory of "animal electricity'" by showing that the electrical current is generated by the combination of two dissimilar metals. [[Image:Voltaic_Pile.jpg|thumb|Voltaic pile]]His assertion was that the electrical current came from the metals and not the animal tissues. (We now know that both Galvani and Volta were right.) To prove his theory he develops the voltaic pile in 1800 (a column of alternating metal discs - zinc with copper or silver - separated by paperboard soaked in saline) which can deliver a substantial and steady current of electricity. Enthusiasm in the use of electricity leads to further attempts at reanimation of the dead with experiments on recently hanged criminals. Giovani Aldini (the nephew of Galvani) conducts an experiment at the Royal College of Surgeons in London in 1803. The executed criminal had lain in a temperature of 30 F for one hour and was transported to the College. "On applying the conductors to the ear and to the rectum, such violent muscular contractions were executed, as almost to give the appearance of the reanimation". Aldini, J. Essai: Théorique et expérimental sur le Galvanisme, Paris (1804), Giovani Aldini. General Views on the Application of Galvanism to Medical Purposes Principally in cases of suspended Animation (London: J. Callow, Princes Street and Burgess and Hill, Great Windmill Street, 1819). Mary Shelly's Frankenstein was published in 1818. Louis Figuier, Les merveilles de la Science (Paris, 1867), p.653 | ||
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