Gwathmey anesthetic machine, 1913

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SW6934

Gwathmey anesthetic machine, 1913. James Gwathmey (1862-1944) and William Woolsey (1876-1919) were US anesthetists who invented an early continuous flow nitrous oxide, oxygen and ether anesthetic machine in 1912. The gases were routed through two perforated tubes in a glass mixing chamber containing water. The rate of flow could be estimated by observing the force of the resulting bubbles. The apparatus had the main elements which are still present in modern machines; providing an accurate and continuous supply of medical gases such as oxygen and nitrous oxide, mixed with an accurate concentration of anesthetic vapor (such as ether), delivered to the patient at a safe pressure and flow. Henry Boyle's machine, which was based on the earlier Gwathmey-Woolsey apparatus, was introduced in 1917 and became the best known continuous flow anesthetic machine.

SPL / Science Source