The administration of nitrous oxide and oxygen for dental operations / by Frederick W. Hewitt.

  • Hewitt, Frederic W. (Frederic William), Sir, 1857-1916.
Date:
1901
Catalogue details

Licence: Public Domain Mark

Credit: The administration of nitrous oxide and oxygen for dental operations / by Frederick W. Hewitt. Source: Wellcome Collection.

Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.

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    Phonated sounds were less common under nitrous oxide and oxygen than under nitrous oxide and air mixtures. They were commonest with very small and with very large percentages. Reflex and excitement movements were un- common with small percentages of oxygen, but often asserted themselves and occasionally became inconvenient when the proportion of oxygen rose to 10 per cent, or more. Stamp- Pure N i trou5 Oxide Perc A ir wit :e n L ages of NiLrousOxid e Percen \Jxyser\\j\l\\ \|i bus Oxide 3 5 6 7 10 12 14 15 16 18 20 P^ 25 3C 3 A 5 6 7 8 9]l0!li 20 1 — 1 i 20; 25] 35 40 45 50 55 60 65 70 75 80 85 90 95 A \/\ 1 A / V \ / n; i 1 \ t I \ A / \, < / / V l\ \ / j \ Vj-I ~^ \ ''\/ / V /^ M ^ y 1 i • 1 / 1 -J J.._ .. ,.:. ~ ■^ Fig. I.—Chart showing comparative general results obtained by {a) pure nitrous oxide, (/j) nitrous oxide with different percentages of air, and (c) nitrous oxide with dfferent percentages of oxygen. Arbitrary Numeri- cal Scale.—Perfect type — o ; failure to produce anaesthesia = 200. ing, kicking, side to side movements, &c., were common with from lo to 20 per cent, of oxygen. As regards the general result, the best mixtures for adult males were those con- taining 5, 6, or 7 per cent, of oxygen ; and