John Snow

Biography

• Born March 15, 1813
• Died June 16, 1858

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Medical Eponyms

John Snow Silver Medal (1946)

The John Snow Silver Medal was originally given to anaesthetists who had distinguished themselves and received awards for gallantry in the Second World War. 

In 1946 the first three recipients were the founder of the Association of Anaesthetists, Henry W Featherstone OBE; Leslie G Morrison MC; and Professor Edgar Alexander Pask OBE.

Now awarded to UK and Irish anaesthetists who have held high office in, and provided exceptional service to the Association; or eminent UK and Irish anaesthetists of great distinction

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Key Medical Attributions

Anaesthesia

The first classification system for general anaesthesia was proposed in 1847 by John Snow as the 5 stages of etherization (narcotism); and furthered by Francis Plomley in the Lancet in the same year. Guedel later proposed a four stage classification system to assess the depth of general anesthesia in 1937. This was designed for use with a single inhalational anesthetic agent (ether), in patients premedicated with morphine and atropine.

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Controversies

Dr Snow pioneered an observational study on cholera epidemics in London between 1854-1857 and later published ‘On the Mode of Communication of Cholera’, a paper which managed to trace an outbreak of cholera to the Broad St pump in London.

The Lancet was the first to infer ‘you know nothing John Snow…‘.

More than 154 years after publishing a a scathing editorial (1855) and dismissive obituary for John Snow, The Lancet reflected and acknowledged it had not recognised the epidemiological significance of Snow’s water-borne transmission theory…

• Lancet scathing editorial attack: June 23, 1855 [Dr Snow’s evidence]
• John Snow died: June 16, 1858
• Lancet Obituary – minimising epidemiology: June 26, 1858 [Obituary: John Snow]
• Lancet reflection/correction: April 13, 2013 [John Snow]

The Lancet wishes to correct, after an unduly prolonged period of reflection, an impression that it may have given in its obituary of Dr John Snow on June 26, 1858. The obituary briefly stated:

“Dr John Snow: This well-known physician died at noon, on the 16th instant, at his house in Sackville Street, from an attack of apoplexy. His researches on chloroform and other anaesthetics were appreciated by the profession.”

The journal accepts that some readers may wrongly have inferred that The Lancet failed to recognise Dr Snow’s remarkable achievements in the field of epidemiology and, in particular, his visionary work in deducing the mode of transmission of epidemic cholera. The Editor would also like to add that comments such as “In riding his hobby very hard, he has fallen down through a gully-hole and has never since been able to get out again” and “Has he any facts to show in proof? No!”, published in an Editorial on Dr Snow’s theories in 1855, were perhaps somewhat overly negative in tone.

The Lancet 2013

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Major Publications

Anaesthetics

• Snow J. On the inhalation of the vapours of ether. 1847
• Snow J. On the Inhalation of the Vapour of Ether in surgical operations; containing a description of the various stages of etherization, and a statement of the result of nearly eighty operations. 1847
• Snow J. On the discussion respecting chloroform. 1849
• Snow J. On the fatal cases of inhalation of chloroform. 1849
• Snow J. The alleged employment of chloroform by thieves. London Medical Gazette. 1850; 45
• Snow J. On narcotism by the inhalation of vapours. 1851 (parts 8-16) (Parts 17-28)
• Snow J. On the cause and prevention of death from chloroform. 1852
• Snow J. On chloroform and other anaesthetics: their action and administration. 1858

Epidemiology

• Snow J. On the pathology and mode of communication of cholera. London Medical Gazette. 1849; 44
• Snow J. On the mode of communication of cholera. 1849
• Snow J. On continuous molecular changes, more particularly in their relation to epidemic diseases. 1853
• Snow J. The Cholera Near Golden Square, and at Deptford Medical Times and Gazette 1854; 9: 321-22
• Snow J. On the mode of communication of cholera. 1855
• Snow J. Report on the cholera outbreak in the Parish of St. James, Westminster. 1855
• Snow J. Cholera and the water supply in the south districts of London. 1856

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References

Biography

• Editorial. Dr Snow’s evidence. Lancet June 23, 1855; 65(1660): 634-637
• Obituary: Dr John Snow. Lancet June 26, 1858; 71(1817): 635
• Hempel S. John Snow. Lancet, 2013; 381(9874): 1269-1270
• Frerichs RR. Life and times of Dr. John Snow (1813-1858). UCLA
• Maltby R. John Snow. Notable Names in Anaesthesia. The Choir Press. 2013: 205-208

Eponymous terms

• Bynum W. In retrospect: On the Mode of Communication of Cholera. Naturev 2013; 495: 169–170
• Nickson C. Just Read the Map. LITFL
• The John Snow Silver Medal. Association of Anaesthetists