Long Island College Hospital - Lichonian Yearbook (Brooklyn, NY)

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ii.. . ,n fi' r , Kiln. . it 2 -if t Fl Hi I 'I Body Surface and Ilfletabolisnz.-The search for suitable standards has centered chiefly about the so-called body-surface law of Rubner who was the first to appreciate the relationship between metabolism and surface area. The principle embodied in this I it, law is that the basal metabolism is a simple function of the body surface. In Kilo E. F. Du Bois and D. Du Bois devised a simple but accurate method , of determining the surface area of the body, 1.e., the so-called height-weight formula. 'El' In other words, one obtains the height and weight of the subject to be tested and ,j then calculates his surface area by means of the Du Bois formula. The determining factor of energy output is undoubtedly the general condition of body nutrition-the active mass of protoplasm of the body QBenedictD. That there ,iii . . . . . IS a relationship between the body surface and metabolism is undoubted, but the maj, relationship is not a casual one. At present, therefore, the only safe method to employ Q in comparing the metabolism of normal and diseased individuals is that called by 55 Benedict the group method, in which the metabolism of groups of persons of like ,ni height and weight is compared, it being assumed that such individuals have the same Vg' general metabolic relations. Hence, much data is being accumulated in regard 'L to the normal figures for healthy men, women, boys, girls, and infants of various types 5-tw for purpose of comparison with diseased individuals. In round numbers, -I-0 calories per square meter of surface per hour is the energy output of normal men C20-401. Women 6.8 per cent lower than that of men. A deviation of 15 per cent. from this standard is high. .llletlmrls of Deferminalion.-The.direri measurement of basal metabolism in- PH volves the use of a complicated respiration calorimeter. QAn apparatus designed for the measurement of the gaseous exchange between a living organism and the atmos- Eiill phere which surrounds it, and the simultaneous measurement of the quantity of heat gl produced by that organism. A complete respiration calorimeter. therefore. combines ,Pig within one apparatus two separate and entirely distinct methods: the one determining the heat production and the other the heat elimination, thus allowing a comparison of the two principlesj, but th-e basal .metabolism is easily measured indirfrtly from the 3513, oxygen consumption and with a fair degree of accuracy. An idea as to the increased consumption of oxygen during muscular work may also be obtained by collecting the Q! air expired by the working individual in a large air-tight bag carried over the shoulders, Q, measuring and analyzing it for oxygen and carbon dioxide. lVIany modifications of Val this latter method have been devised for use with patients and they practicallylall llgl involve the following principle: The subject inspires atmospheric air and expires if into a gasometer through a series of tubes, mask and valves. The expired air, having been measured and its volume corrected, is analyzed for carbon dioxide .and olxygeng the amount of oxygen absorbed is calculated on a basis of the ratio of expired nitrogen to atmospheric nitrogen. Dividing the volume of carbon dioxide produced by the oxygen absorbed gives the respiratory quotient. which has a known heat value for each liter of oxygen. In this manner the total calories produced per hour may be calculated. Accepting the heat production as practically proportionate to the surface '.l1:,. 'r: .k 'l'jil,!.i::-L. -- :g.,L49QLTJ, l, ,,, , -A .. .- U G Q1 Jffrpxufyi. el gl, .i i - -. ga-'el' b if -,ff - eritiiiifiiyiigll - 'mi .. , -Hifi UU-- -:f1mfr 'z 'e Q f'. Fi. ii I -E fl -22 ., .,.'.-'M l.-.w':- 1 f-f'.4 Yhgfil if gl ,il i .L . - -.--.. - ,- - -... ...WA ...LL-.,. 1- -' --4-1 area determined by the Du Boises and the Du Bois formula, the calories produced may be expressed in terms of calories per square meter of body surface per hour. This result, the basal metabolism, is usually reported as the percentage above or below the average of Du Bois normal standard. Page thu iv

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fy, TW., f .-.-,Q ,ia , .A E-x ,V , .. -qwq-ip:-1feen1vp-f-we-:Ev-F-,.qy-. '-g,',.' .ff -155,1 ga.f.aL36m.frhe..2..ff .1vfc:vf.fbL:.f..:1 Ae.. , nt Y. ,. ,. Y . , Tie A v'1 . 'H1'l E157 ,..-.'f'1::fp:...g:t:. ..gzQ,,.,.s , T..-.f 1 ',...':cax::1e31....i:g'3-.1...., -,T ,, il ll 1 xxx , Q X. F . :Vex Nw 2 I '- in -i 1 'A . - . 1 4 11 17 ,f J Ill X F J- H 'Liz '5 nu nz 1 :mils ', ' F W? g 1 ' 1 1 111111 El 5 'tl ' , , In . A U - I W . I 1 .1 Q gina-5 --We ,QA t - --. 2:-2:5 F25 55.11 ,vmofvfs 'TURY.-Tests on basal metabolism began in Europe about 1894 with .utamvml IS I L C , 1 , 'fn AUM, if L the Zuntz-Gepperts intricate gas-analysis apparatusg and in America ,rw L me about 1905 with Atwater's room calorimeter.. Manjr simplified forms Fl! limi l l of apparatus have recently been developed ID America. llflethods of application have been devised and elucidated. The result of these researches is, that accurate standards are now available to clinicians by which they may judge the normality or abnormality of the basal meta- bolism of their patients. Basal metabolism is the condition of minimal or fundamental exchange, the irreducible minimum of exchange of energy which is characteristic for the individual. It is the minimal activity of the body which maintains the functions of respiration, circulation, and secretion. It may also be considered as the sum total of all the vital activities of the quiet organism in the post-absorptive conditiong i.e., the minimum of maintenance metabolism unaffected by extraneous factors. This may be ex- pressed in terms of heat produced or-of gaseous exchange incidental to heat production -carbondioxide production and oxygen consumption. Using this basal metabolism as a standard, we may then measure definitely the superimposed factorsf, Normalily of Subjects.-The clinician must compare the metabolism of his patient against the basal metabolism of a normal subject. But, one might ask: Wl1at is a normal subject P Strictly speaking there is no such thing, because what is normal to one individual is not normal to another. Yet a person who is in good health and has no abnormal physical characteristic has been generally accepted as meeting the requirements of the case. flcreptezl Basal Illetabolif Standard.-The basal metabolism is always measured after fourteen hours of fasting and twelve hours of repose-and unaffected by physical exertion, or extraneous disturbance. Relationslzip Between Age and Standards.-One would expect age to have a definite bearing on metabolism, and research has proved this to be true. The level of the metabolism varies greatly with age. During the first few days of life it is very low, then rises rapidly during infancy, and reaches its highest level 'between the ages of 2 and 6 years. After this it falls rapidly until about the 18th year when the curve flattens out. Between the ages of 20 and 40 there is comparatively little changeg but after this a slight fall, so that by the 80th year the line is about 10 per cent. below the average for the ages of 20 to 40. There seems to be a stimulation to the basal metabolism during the period of growth. Page Iwerity-nine 7Q'.lr'f V '1 .5 K, ll 1. 1 1' V-1 11? tn 1.3 1 11.1 1 '1 ,111 .111 .fx .11 1r1 1 1 P a. 11RljV1 li .11 . 1 411 11 ,1 1 ,,. 1 11 155111 Y.. 1.1! 1 111 1t.,, ..c. 11:1 1 F V91 111 4 V. I. v. - 111111 1. . 1 ,. .., V . 1.1 1 .,1, 1.11 .14 ,. -v1 Ui 1 X ..1, 1 1,15 111 L ,1 in 'u 1 !11.1. 1 bc' K. P. 1 1 11., .J - 11 51 .J n i 1. 1'1 .1 L v'1 ja, 11 :11 1 1 Li 11 111 1 1 I -4,1 ,ir xfllf- i.l'?:'f1 Wig.-I 'iIi.1f1z?zi, frf' W, jfjl ly I ,1t111..111.1.1 11' 11 l,f,4gif1-pit' . ii, .1-1.s 117, F as .15 H ,311 'S--.1 V C.J.:IJ-- ev 11111151 1 . 1 V

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71 ei ll 3 ' img k sim Bam! Illetalmlisnz In Various Diseases.- All investigators agree that basal metabolism depends largely upon thyroid activity and that an increase in the activity of this gland raises the metabolic rate above normal, while a decrease in thyroid secretion depresses the rate below the normal level. YVhile other ductless glands, especially the pituitary and ovary, control metabolism to a lesser degree. bioreover, certain diseases such as fevers, lymphatic leukemia, hyperpituitarism, severe diabetes, cancer and pernicious anemia increase the metabolic rate, Whereas, starvation, hypo- pituitarism and wasting diseases decrease it. 7 Variations in Thyroid zlfiiirfity.-lt is in thyroid therapy that the basal metabolic rate is used most extensively by clinicians. As some one has tersely put it- In auto- mobile language the thyroid is the ignition System of the body. Under certain conditions any increase or decrease in heat production is usually due to a corresponding change in thyroid activity. The two extremes of its activity are easily recognized. It is the borderline cases, where either a slight hypothyroidism or a slight hyperthyroidism exists that is hard to recognize. Up to date the best measure of the degree of thyroid activity is the determination of the basal metabolic rate. In other words, it is now coming to be recognized that the determination of the basal metabolic rate is as indispensable as is the VVasserman reaction in syphilis, or- temperature determinations in fever. lVlAT'1'I-IEW S'1'EizL. ,, Bio-Chemistry Laboratory Page tliiigty-one Ei 'A Mig' rigs' lg! til I H l I-J! i an yi ,et ii W S4 hr! MM ilfii ltr! '12 I E-fi il? 751' hm lat' is 'b ,S E3 Ml, intl is f , ls s ir, ,Hi ru. Ls, Mil iw iliil lei ua Val rf. ifiil wi Eli: ,ffl li? 4 r S , rf , R951 ,si EQ, fe 1 -,L-f 'QI' , ,,'.' -J ', ,,f, -, 12,157 v. .. i' . 'H Ellalia ' - f ' 5. , if . ,hifi-rT?i: 9 its if It lf?tlElflfllrl?illP? f.'3,.'1ihng:f' Q :ff iris ,tar - 1-- -H' feng? I ' 5 5 Qi igirlflisgif? 1 t t . 5'j',,,.gfJ ,,-.s,,i 1