The static lung tests / by William Augustus Guy.

  • Guy, William A. (William Augustus), 1810-1885.
Date:
[1842?]
Catalogue details

Licence: Public Domain Mark

Credit: The static lung tests / by William Augustus Guy. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    Table XIX. Male. Female. Male and Female. Before After Before After Before After Respiration. Respiration. Respiration. Respiration. Respiration. Respiration. Max. 95,.*>20 77,000 87,336 57,313 97,140 78,912 Min. 30,243 22,396 30,243 19,307 27,030 19,307 Mean, 52,461 43,527 50,831 38,821 51,685 44,266 The mean weight of the bodies of still-born children exceeds the mean weight of such as have lived one day by from about one- sixth to somewhat less than one-third. The natural inference from this fact is, that large children are most apt to perish in the birth. The bearing of the fact upon the value of Ploucquet’s test is ob- vious ; for on the supposition, that the weight of the lungs in the child who has lived one day, is so far increased by the process of respiration as to equal the weight of the lungs in the heavier still- born child,—a supposition which a glance at Table XI. wil] render highly probable,—then the increased weight of the body of the still-born child will have the effect of exaggerating the dispropor- tion between the weight of the lungs and that of the body, and giving to the test a higher value than it deserves. Another fact worth observing, in connection with Ploucquet’s test is, that the weight of the lungs is subject to much greater va- riation than that of the body. Thus in still-born male children, at full time, the maximum weight of the body is 95520 grains, the minimum 30243; whilst the maximum weight of the lungs in the same children is 1800, and the minimum 360 grains. The variation in the weight of the lungs as compared with that of the body, is nearly expressed by the proportion 30 : 19. Nearly the same difference is observable in the body and lungs respectively in the female, and in the two sexes taken together. When respi- ration has continued one day, this proportion becomes for the male 32: 21, for the female 4: 3, and for the two sexes jointly, about 3 : 2. The influence of this fact on Ploncquefs test is not very important. By correcting the large variations in the weight of the lungs by the smaller variations in that of the body, it will bring the proportion existing between the two into somewhat narrower limits. The facts which have just been adduced,—the great variation in the weight of the lungs, that of the body remaining the same ; and the equal variation in the weight of the body, that of the lungs remaining the same; the disproportion in the weight of the body in still-born children, and in those who have survived their birth one day; and the great variations observed in the weight of the lungs both before and after respiration,—these facts would lead us to expect such variations in the proportion which the lungs bear