Copyright
E. A. (Edward Albert) Sharpey-Schäfer.

Text-book of physiology; (Volume v.1) online

. (page 115 of 147)
Online LibraryE. A. (Edward Albert) Sharpey-SchäferText-book of physiology; (Volume v.1) → online text (page 115 of 147)
Font size
QR-code for this ebook


p. 287; Pembrey, "Proc. Physiol. Soe.," Jovrn. Physiol., Cambridge and London, 1894-
1895, A'ol. xvii.

^ Sitzungsb. d. k. Akad. d. Wissensch. zu Berlin, 1890, Bd. xx. ; xxi. p. 393.

■5 Mantegazza, Ann. itniv. di med. e chir., Milano, 1859, vol. clxvii. ; U. Mosso, Arch,
ital. de MoL, Turin, 1887, vol. viii. p. 370 ; 1891, vol. xiv. p. 288 ; Hobday, Journ. Comp.
Path, and Therap., Edin. and London, 1895, vol. viii. p. 20 ; 1897, vol. x. p. 80.

•^ Stern, Virchmo's Archiv, 1889, Bd. cxv. S. 14 ; FaAvcett and Hale White, Journ.
Physiol., Cambridge and London, 1897, vol. xxi. p. 435.

'" This article, p. 841.

^ Deutsches Arch. f. klin. Med., Leipzig, 1875, Bd. xvi. S. 12.



82 2 ANIMAL HEAT.

recovered in a day or two. In other cases, with temperatures 28°"4,
27°, and 26°"4, death followed in about twenty-four hours. In a
case observed by Kicolaysen i the rectal temperature was 24°"7, but
the drunkard, who had been exposed for a whole night to air 6°
below zero, completely recovered ; the temperature of the vagina and
axilla was 27'''9 in a woman who had had a similar experience, but
within six hours the temperature rose to 36''3 imder treatment, and the
patient completely recovered.- In four cases of insanity, Lowenhardt ^
has observed temperatures as low as 25°, 29°"5, 23°"75, and 28° ; in one
case the range of temperature for several weeks was from 25° to 35°.
The patients were about 60 years of age ; they often ran about naked
in cold weather, and were frequently iDathed on account of their dirty
habits, and although they were fairly active they did not take much
food. The observations were taken sometimes in the axilla, sometimes
in the rectum.

Weiland ^ has recorded two cases of adults with temperatures
reduced to 28°'4 and 26°"6 from exposure to cold ; the observations were
taken in the rectum several hours before death ; in a third case, that of
a drunkard who had been exposed to cold, the rectal temperature was
30°"4, and recovery took place. The rectal temperature of a man suffer-
ing from bronchi-ectasis was found by Liebermeister ^ to be 32°'6, and
that of a child five days old, suff'ering from sclerema and icterus,
32'"15 ; the readings were taken a day or two before death, and several
thermometers were used and tested. Kohler ^ observed a temperature
of 28°"2 in the rectum of a drunkard, and found that, notwithstanding;
treatment, it remained low until shortly before the man's death a month
later; two cases, with rectal temperatures 26°*8 and 26°"7, were observed
by Quincke;" the subnormal temperature was due to exposure to cold,
but both of the patients recovered. Numerous records of subnormal
temperatures will be found in papers by Janssen,'' Lemcke,^ and Glaser.^

In the case of non-hibernating mammals an artificial cooling of the
body to 18° is in a few hours followed by death, unless artificial respira-
tion and heat be applied. Eabbits cooled to 18° are perfectly helpless
and paralysed ; the heart-beat is feeble, 16 to 20 per minute ; the respira-
tion is either exceedingly slow or rapid and shallow ; the nerves and
muscles long remain irritable, and during operative procedures there is
very little bleeding, owing to the low blood pressure.^''

It was shown by Edwards ^^ that newly-born pups and kittens would
live for two or three days with their temperature reduced as low as 17°
or 20°, and that the application of artificial warmth would restore the
young animals, if this low temperature had not persisted too long.
Adult animals, however, when cooled to 18° or 20°, generally died, even

^ Jahrtsb. u. d. Leisttmg. . . . d. ges. Med., Berlin, 1875, Bd. i. S. 283.

- Peter, Gaz. held, de mid., Paris, 1872, p. 499.

■■ Allcj. Ztschr.f. Psijchiat., etc., Berlin, 1868, Bd. xxv. S. 685.

^ Schrift. d. Univ. zu Kiel, 1869, Bd. xvi.

5 "Handbuch d. Path. u. Therap. des Fiebers," 1875, S. 69.

I Schrift. d. Univ. zu Kiel, 1873, Bd. xx.

"• Quoted from .Janssen, Deutsches Arch. f. klin. Med., Leipzig, 1894, Bd. liii. S. 249.

^ Ibid., 1883-84, Bd. xxxiv. S. 90.

^ "Ueber Vorkommen iind Ursachen abnorm niedriger Kbrpertemperatur," Diss.,
Bern, 1878.

^" Walther, Virchow's Archiv, 1862, Bd. xxv. S. 414; ibid., 1865, S. 25; Horvath,
Verhaiidl. d. phys.-med. Gesellsch. in Wiirzburg, 1881, Bd. xv. S. 187 ; Tscheschichin,
Arch. f. Anat., Physiol, u. ivissensch. Med. 1866, S. l.'J.

^^ " De I'intiuence des agens physiques sur la vie,"' 1824, p. 237.



BODILY TEMPERATURE COMPATIBLE WITH LIFE. 823

when artificial warmth was apphed. Similar results were obtained in
the case of recently hatched and old birds.

Hibernating mammals have been ol^served during winter with
temperatures as low as 2°, and during summer they may \)Q cooled by
artificial means to l°-2 ; in these cases the animals are able to again raise
their temperature without any external aid (Walther, Horvath, and
others).

The eggs of silk-worms and of other insects may be exposed for a
long time to temperatures 20" to 30° below zero, and yet will develop
into larvae when removed to warm surroundings.^ The Arctic ex-
plorer Eoss exposed caterpillars to a temperature of -42°, and found
that they recovered when slowly thawed. Colasanti'^ observed that
hens' eggs could be exposed for two hours to a temperature of -4°, and
for half an hour to a temperature of -7° to -10°, and yet developed
normally when placed in an incubator.

As already pointed ont on p. 817, in the lower vertebrates the tem-
perature of the body may sink to zero and yet recovery take place.
Hunter ^ placed an eel in a freezing mixture, until the temperature of
its stomach fell to — 0°'6, when the animal appeared to be dead, but
by the next day it had recovered ; a similar result was observed in a
frog. Frozen leeches, however, were dead when thawed.

As regards the limit of high temperatures compatible with human
Hfe, there are numerous records of cases of hyperpyrexia. The highest
observed by Wunderlich * was 44° '75 (112°-55 F.) in a case of tetanus;
one hour after death the temperature was 45°'37. Currie ^ found a
temperature of 44°"45, Woodman^ one of 46"1 in fatal cases of scarlet
fever ; Baumler '^ records a case of sunstroke in a healthy man, the
temperature in the axilla was 42°'9, there was deep coma, and death
took place in eight hours ; in a similar case observed by Casey ^ the
temperature in the axilla was 43°"1, and death occurred within three
hours. Levick ^ gives cases of sunstroke in which the temperature was
42°"8, and the patients recovered. Fatal cases with temperatures 43°,
42°-5, and 44° are recorded by Simon,^^ two cases of tetanus with
temperatures 44°'4 and 41°-6 before death by Lehmann,^^ and others
with 43°-4, 43°-6,42°-75, 43°-4, 43°-4, 44°-3, and 43° by Quincke.12

On the other hand, Donkin ^^ gives cases of temperatures as high as
44° -2, 45°, and 44°-5, in which recovery took place ; the high temperature,
however, appears to have persisted for a very short time. In two cases
of rheumatic hyperpyrexia recorded by Arkle ^* the temperature was
43°-55 (110°-4 F.), but the patients recovered.

^ Reaimuu", "Mem. sur les insectes," tomes ii. andv. ; Spallanzani, "Opusc. de phj's.
anim.," tome i. pp. 82-85 ; Bonafous, '' Biblioth. imiv., Geneve, 1838, tome xvii. p. 200 ;
Ross, ihicl., 1836, tome iii. p. 423 ; Pictet, Arch. d. sc. phys. et nat., Geneve, 1893 (3),
tome XXX. p. 293.

^ Arch. f. Anat., Physiol. «. ivissensch. Med., 1875, S. 477.

^ "Works," Palmer's edition, London, 1837, vol. iv. p. 131 et seq.

■* "Medical Thermometry," p. 204. ^ "Medical Reports, etc."

^ Med. Mirror, London, 1865, p. 77.

'' Med. Times and Gaz., London, 1868, a'oI. ii. p. 118.

^ Ibid., 1866, vol. ii. p. 26.

^ Penn. Hasp. Pep., Philadelphia, 1868, vol. i. p. 369.
10 Char ite- Ann., Berlin, 1865, Bd. xiii. Heft 2, S. 1.
" Schmidt's Jahrb., Leipzig, 1868, Bd. cxxxix. S. 241.
^^Berl. klin. JVchnschr., 1869, S. 301.
12 Prit. Med. Journ., London, 1879, vol. ii. p. 983.
!•* Trans. Clin. Soc. London, 1888, vol. xxi. p. 187.



824 ANIMAL HEAT.

Eichet 1 has collected three cases in which the temperature rose to
46'^, but the patients recovered. Numerous other cases of high
temperature in man are to Ije found scattered throughout medical
literature.^

Experiments upon animals have determined more exactly the limit of
high temperature. Bernard ^ found that when the internal temperature
of rabbits was artificially raised to 45" they died; in birds the fatal
limit was 51° or 52°. According to this physiologist, death was due to
stoppage of the heart by the hot blood, which sent the muscle into rigor
mortis. Eosenthal * obtained similar results for rabbits, but found that
if the animal was removed to cooler surroundings w^hen its temperature
had reached 44°, recovery might take place. From these and similar ex-
periments by Obernier,^ Wood,*^ and others, it may be concluded that a
bodily temperature of 45° is extremely dangerous, and one of 47° quickly
fatal, to the life of mammals. The limit of high temperatures appears
to be fixed by the point at w^hich the proteids of the body begin to
coagulate.

The TeiMperatuee of Different Parts of the Body.

The heat of the body is produced by processes of combustion taking
place chiefly in the muscles and glands, while heat is lost chiefly from the
surface of the skin. The result, therefore, is that the temperature of
the body diminishes from the interior to the surface. It is impossible,
however, to give any exact value to the temperature of different parts,
because the production and loss of heat vary under different conditions
of the animal, such as muscular activity and digestion.

The temperature of internal parts in man. — In considering this
subject, it is important to remember that the temperature taken by a
thermometer placed in a dry, well-closed axilla represents the heat of
an internal cavity ; Einger and Stuart '^ even state that, " due care
being taken and sufficient time allowed, the temperature of the axilla
is always identical with that of the mouth, and with that of the rectum
four to six inches above its termination."

Upon the respective temperatures of the mouth, axilla, and rectum,
there is a great want of agreement among observers. This is in great
part due to the fact that in numerous cases insufficient time is allowed
for the determination of temperature in the mouth and axilla ; but there
is another cause, which is beyond the control of the observer — the
circulation of l)lood in the mouth and in the skin of the axilla is liable
to marked variations. It will be well, therefore, to mention the dis-
cordant results obtained, and then draw some general conclusion. As
just mentioned, Einger and Stuart state that the temperature in the
axilla is identical with that of the mouth and rectum ; Ogle ^ says that

1 Compt. reiid. Soc. de bioL, Paris, ]894, p. 416.

^ Hale White, Brit. Med. Journ., London, 1894, vol. ii. p. 1093. Here numerous
references will be found. See also Trans. Clin. Soc. London, 1882, vol. xv. p. 2(il.

^' Gaz. mid. de Paris, 1859, tome xiv. p. 462; " Lecons sur la clialeur animale,"
p. 349.

* " Zur Kenntniss der Warmeregulirung liei deu warml^llitigen Thieren." Erlaugen,
1872, S. 15.

5 " Der Hitzschlag," Bonn, 1867, S. 71.

" "Fever," Smithson. Contrih. Knoicl., "Washington, 1880, No. 357.

"^ Proc. Roy. Sor. Jjondon, Idill , vol. xxvi. p. 186.

^ St. George's Husp. Rep., London, 1866, vol. i. p. 233.



TEMPERA TURE OF INTE RNA L PARTS IN MAN. 825

if the thermometer be warmed by the hand and then kept under the
tongue in the closed mouth for eight minutes, the reading is the same
as that ol^tained by inserting the thermometer in the urine as it leaves
the body. On the other hand, Crombie ^ found, as the result of com-
parative experiments in which care was taken to obtain accurate
results, that in fifteen simultaneous observations the mean difference of
temperature in the mouth was OlS above the reading in the axilla, and
in thirty-five determinations the mean difference in the rectum was
0-22 above the temperature in the mouth. A number of simultaneous
observations made by Parkes and Wollowicz^ show that the rectal
temperature of a healthy man may be 0-3 to 0-6 higher than the
temperature in the axilla. Gassot ^ made comparative observations at
different times of the day, with the following results : —



Time.


Man.


Woman.


Mouth.


Axilla.


Moiith.


Axilla.


Rectum.


7 a.m.


37°-06


37°-78


37°-0


36°-8


37°-7


2 p.m.


37°'6


37°-3


37°-6


37° -3


38°-0


9 p.m.


37°-4


37°-12


37°-5


37°-3


37°-8



Oertmann * observed, when the thermometer was kept in the axilla
for fifteen minutes, in the rectum at a depth of 7 cm. for five minutes,
and in the stream of urine for five seconds, that the temperature of the
urine was generally equal to that of the rectum, but four-tenths of a
degree higher than that of the axilla. Ten simultaneous observations
of the temperature in the mouth and rectum gave an average difference
of 0'32 in favour of the latter (Cuny Bomder).^ According to Lieber-
meister,^ the rectal temperature is 0°"1 to 0'''4 above that of the axilla.

Lorain '' maintained that the temperature in the rectum or vagina
alone represented the internal temperature of the body, and that the
rectal temperature was '6° to "8^ higher than that in the axilla. The
figures given by Wunderlich ^ for the mean temperature of the rectum,
mouth, and axilla are 37°'3, 37""15, and 37° respectively. Eedard,*^ on
the other hand, states that the temperature of the mouth is -2° higher
than that in the axilla, and -3° to "6° lower than that of the rectum.
Neuhauss ^° found, as the result of forty comparative experiments, in
which the temperature w^as observed simultaneously in the rectum
and in the axilla, that tlie rectal was 0°-6 higher than the axillary
temperature.

We may take as our guide the averages obtained from the results
of different observers, and conclude that the rectum has a temperature

1 Indian Ann. Med. Sc, Calcutta, 1873, vol. xvi. p. 558.
- Proc. Roy. Soc. London, 1869-70, vol. xviii. p. 368.

2 These de Paris, 1873, quoted from Richet, liev. scienL, Paris, 1885, tome ix. p. 433.
^ Arch. f. d. ges. Physiol., Bonn, 1878, Bd. xvi. S. 101.

'^ Ibid., '1869, Bd. ii. S. 387.

" " Handbuch d. Path. u. Therap. des Fiebers," S. 44.
^ " De ]a temperature du corps humaiii," Paris, 1877, tome i. p. 434.
** "Medical Thermometry."

^ ■' Etudes de thermometrie clinique," 1874. p. 20.
10 Virchow's ArcUv, 1893, Bd. cxxxiv. S. 365.



826



ANIMAL HEAT.



0°'4 above that of the mouth, and that the difference between the
temperature of the axilla and of the mouth is so small that it may Ije
neglected, especially since the variation is not constantly in favour of
the one or the other.

The temperature of internal parts in animals. — Numerous
observations have lieen made upon the temperature of the internal
parts of animals, either during life or immediately after death. Some
of these results are now given in the following tables : ^ —



Animal.



Dog
Dog

Lamb
just dead



Dogs



Lambs |
(four) \
just dead ]



Temperature of Part.



Dog



Lambs [
(three), ^.
just dead [

Turkey, /
just dead !



Rectum, 38°

Right ventricle, 38° -3

Liver, 38° "2

Stomach, 38° -3

Aorta, 38°-6

Portal vein, 38° "8

Rectum, 40° 'S

Liver, 41° '4

Lung, 41° "4

Right ventricle, 41° "1

Left ventricle, 41° '7

Blood of jugular vein, 40° "8

Blood of carotid artery, 41°'7

Blood in abdominal aorta, 38° '3-38° "6

Rectum, 40°, 40°-6, 40°-6, 40°-6

Right ventricle, 40° -8, 40° -6, 40° '8,

41°-1
Left ventricle, 41°-1, 41°-1, 41°-4, 4l°-7
Blood of jugular vein, 40°
Blood of carotid artery, 40° "8
Portal vein, 40° "2
Hepatic vein, 40° "S

Brain, 40°, 41°, 40°-8
Rectum, 40°-4, 40°-8, 41°-4

Cloaca, 42° -2
Gizzard, 42°-8
Pectoral muscle, 42° "2



Observer.



Hunter.^

5)

Bernard.
Davy.^



Bayliss and Hill.
Davy.^



Bernard.^



Davy.
Davy.*^



Hobday ^ finds in the case of horses, cows, sheep, dogs, and pigs, that
the vaginal temperature is generally one-tenth of a degree lower than
that of the rectum ; at the times of oestrum, however, the vagina often
has the higher temperature.

The temperature of arterial and venous blood. — The temperature
of the blood has attracted considerable attention for many years —
first, on account of the ancient view that the heat of the body was
produced in the heart; and, secondly, because the work of Lavoisier
and Crawford tended to show that heat was produced in the blood
as it passed through the lungs or other parts of the body. More re-
cently, attention has again been directed to this question by Berthelot,^
who shows that a certain amount of heat is formed in the lungs by

^ The results of other observations will be found in Rosenthal's article, Hermann's
'• Handbuch," Bd. iv. Th. 2, S. 393.

^ "Works," Palmer's edition, London, 1837, vol. iv. p. 145.

^ "Researches," London, 1839, vol. i. p. 147 ; Phil. Trans., London, 1814, p. 590.

* Journ. Physiol., Cauiljridge and London, 1894, vol. xvi. p. 351.

" " Leoons sur la chaleur aniiiiale," 1876, p. 188.

•^ "Researches," London, 1839, vol. i. p. 159.

" Vet. Record, London, 1896, vol. viii. p. 488. « This article, p. 839.



TEMPERATURE OF ARTERIAL AND VENOUS BLOOD. 827



the combination of oxygen with hiemoglobin. The numerous results
obtained by different observers have been collected by Bernard,^ and
are given in the following tables : —

Table I.
Besults in which the Arterial Blood is ivarmer than the Venous.



Author.


Arterial
Blood.


Venous
Blood.


Differ-
ence.


Animal.


Part Examined.


Method.


Haller2 (1760),


37°-2


36°-l


1°-1


1


?


1


Schwenke














Crawford2(1778)


38°-8


37°-5


l°-3


Sheep.


Carotid artery, jug-
ular vein.


Thermometer
placed in
blood col-
lected.


Krimer (1823)


38° -18


37° -20


0°-98


Man.


Temporal artery,
jugular vein.


Thermometer
in jet of
blood.




37° -5


36°-6


0°-9


Woman.


,,


,,




37°-2


36°-3


0°-9


Man.


Amputation of arm,
brachial artery
and vein.


"


Scndamore"*


37°-7


36°-6


1°-1


Sheep.


Carotid artery, jug-


;,


(1826)










ular vein.






36° -1


35°-5


0°6


Man.


Temporal artery,
vein of arm.


"


Saissy'^(1808)


38°-5


38°-0


0°-5


Marmot.


Right and left
ventricle.


Incision of
heart.




36° -5


36° -0


0°-5


Hedge-
hog.


"


"




38°-0


37°-5


0°-5


Squirrel.




Experiments
on two ani-
mals com-
ptared.




31°-4


31°-0


0°'4


Bat.


,,


,,


J. Davy 6 (1815)


40° -0

40° -5
40° -5
40° -5
40°-5


39°-l

40° -0
40°
39° -7
40° -0


0°-9

0°-5
0°-5
0°-8
0°-5


Lamb.


Carotid artery, jug-
ular vein.


One thermo-
meterinvein,
anotherinjet
of arterial
blood.




40°-2


39°-7


0°-5


Ewe.


,,






40° -0


39°-l


0°-9


)'


,,






40° -0


39°-4


0°-6




,,






38° -e


37°-7


0°-9


Ox.


;)






38° -3


38°-3


o°-o


J J


)!




Nasse^(1843)


41°-1


40°-8


0°-3


Lamb.


Right and left
ventricle ; great
intestine, 40° "0


Animals just
dead, chest
opened, ven-




41°-1


40 -5


0°-6


jj


40°-5


tricles in-




41°-]


40°-8


0°-3


, ,


40°-5


cised.




42° -8


41°-25


l°-55


1


,,


)j




41°-8


40°-6


l°-2


?


)!


))




42°-5


41°-25


l°-25


?


"


>>



[Continaied on. next page.



^ " LcQons sur la chaleur animale," 1876, p. 40 et seq.

- " Elementa Physiol.," 1760.

^ "Experiments and Observations on Animal Heat," London, 1779.

■^ "An Essay on the Blood," London, 182:!.

^ "Recherclies experinientales, " etc., Paris, 1808, p. 69.

« Phil. Trans., London, 1814.

'' Hheinisch. u. JFestphal. Corresjpondenzbl., 1843, 1844, 1845.



828



ANIMAL HEAT.
Table I. — continued.



Author.


Arterial
Blood.


Venous
Blood.


Differ-
ence.


Animal.


Part Examined.


Method.


Becquerel and






0°-84


Dog.


Aorta where it left


Thermo - elec-


Breschet-^










heart ; inferior


tric ueedles,


(1839)






1°-12

0°-84
0°-84


3)


vena cava where
it entered heart.

Crural artery and
vein.

Carotid artery, cru-
ral vein.


chest opened
in animals
just dead.




38°-90


38° -0


0°-90


"


Crural artery and
jugular vein.





Table II.
Results in which the Venous Blood is warmer than the Arterial.



Author.


Arterial
Blood.


Venous
Blood.


Differ-
ence.


Animal.


Part Examined.


Method.


Berger ^ (1833)


40°-90


41°-40


0°-50


Sheep.


Eight and left
ventricle.


Not stated.


Collard de Mar-






l°-0


Dog.




Animal just


ti gnv,^ and












dead ; chest


Malgaigne
(1832)
Magendie and








Horse.


Right ventricle


partly open.
Animal alive ;


Claude Ber-










warmer than


circulation


nard (1844)
Claude Bernard






...


Dog.


left.
Inferior vena cava


not inter-
rupted.
Animal alive ;


(1849)










at level of liver
warmer than
aorta.


thermometer
introduced by
the abdomen.


Hering4(1850)


3S°-77


39° -30


0°-53


Calf with
ectopia
of heart.


Right and left
ventricle.


Incision of ven-
tricles.


G.Liehig5(1854)


36°-32


36° -35


0°-3


Dog.




Animal alive ;
circulation
not inter-
rupted ; ther-
mometers in-
troduced by
vessels of neck


Claude Bernard


38°





38° -2


0°-2


Dog.






(1857)


39°
39°


3

1


39°-5
39° -2


0°-2

o°-i


"




"




38°


6


38°-8


0°-2










38°


5


38° -7


0°-2


,,


,,


,,




38°


6


38°-8


0°-2




^j






39"


1


39° -2


o°-i




.J






38"


7


38°-9


0°-2




,,


j^




38°


8


38° -9


o°-i










39°


2


39° -4


0°-2










40°
39°


12
92


40° -37
40° -32


0°-25
0°-40


Sheep.




"




39°


58


39°-60


0°-02


jj




,,




40°


24


40°-39


0°-15


J,




,j




39°


58


39°-87


0°-29






jj




40° -09


40° -48


0°-39




))


"



^ Ann. d. sc. nai., Paris, "Zool.," Ser. 2, tomes iii. and iv.

" Mem. Soc. de phys. et d'hist. nat. de Genei^e, 1833, tome vi. p. 353.

^ Jotm'n. compl. d. sc. me.d., Paris, 1832, tome xliii. p. 386.

* Jrch. f. physiol. Hcilh., Stuttgart, 1850.

•' "Ueberdie Temperaturunterschiede iles venosen undarteriellen Blutes," Giessen, 1853.



TEMPERATURE OF THE SKIN. 829

It will be seen from the two taljles that the results lead to directly
opposed conclusions, but a critical examination shows that the correct
one is probably that the blood in the right ventricle is 0°-l to 0°-2
warmer than that in the left. In many of the older experiments the
methods were inexact, the chest was opened and the heart exposed ;
the right ventricle, on account of its thin walls, would cool more quickly
than the left, as shown experimentally by G-. Liebig. The most exact
method appears to be the insertion of delicate thermometers or thermo-
electric needles down the jugular vein and the carotid artery into the
right and left ventricle respectively. This method was employed by
Heidenhain and Korner ^ in numerous experiments upon dogs, with the
result that in all but one of the observations the right side of the heart
was warmer than the left. Thus in one case the difference was '6°,
in two "5° to '6°, in three '5°, in five ■'0° to "4°, in twenty-seven '2° to '3°,
in thirty-six "1° to "2" , in twenty-one "15°, in one case no difference at
all. To determine whether the inspiration of cold air was the cause of
this difference, Heidenhain and Korner made comparative experiments,
employing for artificial respiration in the one case cold air (17°), and in
the other hot air (40°) saturated with moisture. The difference still
remained, and it was therefore concluded that respiration was not the
cause ; cold air when inspired is warmed and saturated with moisture
before it reaches the alveoli ; ^ further, in passing through the upper
parts of the respiratory tract, the cold air would cool the blood in veins
going to the superior vena cava and thus to the right side of the heart.
These observers conclude that in the dog the right ventricle is warmer



Online LibraryE. A. (Edward Albert) Sharpey-SchäferText-book of physiology; (Volume v.1) → online text (page 115 of 147)