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The peripheral blood flow and rectal and skin temperatures in hypertension
T
1113 sulJ,ject of hypertension has engaped the attention of man!. investiq~~toi~~ in recent years. St~imulus was given lo tlww investigations I~,I. tlw ttslwriwents of Goldblatt and his associates relating to tlw rise ill 1~100~1l)wssut-e whic.11 I’ollows the preparation of an iwhemic kidnq-” ” and ty.- the studies 01’ I'iig~'~~ ' I'('lating to the chemical background of hylwrtension. The s\qit~nl t watment ~1 hypertension, which has also increased the intrrcst in anal stlllly ~)t’ thiq $II~I.iwt, will he discussed in a succeeding pal~ir.‘,
Pickering;’ found the rate of 1~100~1HOIV through the i’orca~~n in t1ylwrtc~nsi\.(~ sui)jects the same as t,hat in subjects with normal l)lood pressure ant1 wn~litd(~ti that, owing to \asoconstriction, the resistance oRwed by the resscls oi the i‘~w a 1x1 is increased in hypertcnsiun. ~‘rinzilletal aild ~~ilS(JIl” ah i’(JUll~l t/lilt thi wstiug blood flow in the arm \vas within norm;11 limits and wic~lri~l~~~l that increased vascular resistance is not confined to the splanchnic aw;l \Jlit is ,gm chralizetl t~hroughout the systemic circulation. Abramson and I;liet.st.l” using tilt, venms occlusion plethpsmographic method, found that the resting ~~1o1.d f f o\: through the arm and leg was significantly great,er? IJU~ that thro~~gh tlic, hand uxs 1~s in hypertensive subjects than in normal snhjects. They wn~Iuclcd that t iirir observations directly contradicted the prevailing theory that there is ~II c~r:rlized and uniformly increased periphwnl rcsislarice in hypertension. ( )ne of the results of t.hcse studies has IKY~II the acwunnlation Of’ :I \-;wt atnaltrlt of literature which has contributed much to the understanding ol’ hypeI.tension. However, the mechanism of hypert,ension, whether it is of nerwus 01 tiun1wal origin, still remains unexplained. It appeared to us that a study oi the total peripheral blood fiow in essential hypertension might 1~ OFinietw~ in supported twwi\
by wl
for
a grant publication
from the John and Aug. 2, 1945.
Mary
R.
?darkle
Foundation
the whole general problem as there are ~~~J1lfiiCtill,01 vi,,,, abtrut, the ~)lC,Oll ilo\\ in local areas. We have accordingly- measurttl the amomll oi’ I~10011 all01 1~1110 the peripheral circulation in 1Jaticnts sui’f&il;: from cssenliill h~~!wl*l msiol!. IJ:lIWl t]lC C:i’fWl ‘. These observations form the basis oi’ this report. II1 all(JthC!l’ on the peripheral blood flow cd’ spli~n(~h~~i~ resection I’or the loc~ring 01’ IJ~~JW~ pressure will be appraised.” Sixty-nine observations were made on 56 patients who had aH(t,.iiII II~~J(,I~tension ; 25 were men, and 31 w(‘r( wonicn. The ages r;rngtd Prom ICI to 66 years. The peripheral blood flow wa.s measured by our moclification”~ I2 of thcl method of Hardy and Soderstrom.‘” Hardy and Soderstrom have shown that. a,t a t,emperature below 28” C., the skin fun&ions like a dead insulator when the sub,ject is lying nude in the basal state, and that blood flow to the skin, thermal conductivity of the peripheral tissues, and vaporization are constant and minimum. With an increase in blood flow to the periphery, more heat, is brought from the deeper tissue to t,he surface. This increases lhe thermal eonductanc~c of the superficial tissues; therefore, changes in thermal conductance become an index of peripheral blood flow. With this met,hod, blood flow is expressed as a function of heat loss. surface area7 c&cel*cJyeweiglltcNd sluh fenzpernt~rtm, ant1 rectal temperature. The method requires the recording of skin and rectal temperature13 at known intervals, oxygen consumption,‘4 height, and body weight.‘Zl lri The skin temperatures were recorded with a Hardy-Sodcrstront radiometeP from eleven points on t,hc anterior surface of the body as shown in Fig. 1. With this method the amount of blood allocated to the whole periphery of the body is measured, rather than the flow in local areas, a.nd may 1)~ c~sp~~srctl in cubic centimeters per square meter of body surface per minute. E%?L of Proced~cre.-The plan of procedure was that described in recent publications.‘*~ li All measurements wcrc carried out in the morning beforcb breakfast with the patients in a basal metabolic state. They were brought 111 the constant temperature room and allowed to lie in bed nude, covered onI\, with a sheet. One hour was allowed for ad,@stment to the room temperat,urc Measurements of skin and rectal tc.mperaof 27” C. and 50 per cent humidity. tures were made at twenty-minute intervals. Each set of observations covere(I a period of sixty to one hundred minutes. Blood pressure and pulse rate w;~r~’ recorded between temperature readings. The basal metabolic rate was mcasurrtl at the beginning and again at the end of the morning’s observations. Four to six set,sof skin and rectal tcmpcrntures ncre recorded from which three to five estimations of peripheral blood flow could be made fog the morninir. The data recorded in Tal~lc I for each date show the avcragcs of the pcriphc~;xl blood flows, temperatures, blood pressures, and heart rat-es for the morning.
The results of the observations are shown in Table 1 and E’ig. 1. Blood Flow.-The average peripheral blood flow of the whole group was 5’1 CL per square meter of body surface per minute, as compared
Periphel*al
with 73 C.C. per square meter per minute for a group of normal young male suhjects’Y at the same room temperature (Table I, Fig. 1). While the periphrrnl blood flow is statistically significant in the g-ro11p of normal young adults, the fluctuations in the hypertensive groups are such that the dif?erence from the young; normal ma!c group is not significant. There was no significant clifferww in t IIt) peripheral blood flow in the men of the hypcrtensire group as wnipared
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,
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E. ‘5575 56
2/10/44
verage-men verage age = 36 yr. ;andard deviations about the means
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121 3/43
. McD. 5209 r. 48
. L. i1331 :. 31
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37.11;
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0.60
0.24
54
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33.74
37.27
61
34.89 34.51
32.25
33.52
33.97
34.30 33.97
37.36 37.11
36.94
37.11
36.81
37.27 37.10
136 108
25
25
81
62 70
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-
-
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34.z’
0.7
34.8
35.6 35.4
34.4
34.9
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34.7
35.3 35.0
34.3
33.5
34.7
35.1 34.8
0 c.
o c.
35.3 35.0
2
1 0 c.
4
22.9
34.3
0.8
34.3
35.0 34.7
32.8
33.7
34.4
34.5 34.3
0.7
34.1
34.9 34.5
33.4
33.9
33.9
34.4 33.4
32.S
33.7
X.9
34.3
o c.
ti
ARE-IS
o c.
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34.5
35.3 35.1
32.7
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33.2
34.6
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32.0
32.9
* c!.
11
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32.5
33.7 33.”
30.2
32.0
32.5
33.2 33.9
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34.4 34.4
31..5
32.5
33.4
34.4 34.5
3O-. 8
33.2
.72 .LS
33.2
3:t.S
33.3
Female Subjects
1.1
32.8
33.4
30.1
32.2
33.3
33.5 33.2
34.7 34.4
0.9
a c.
10
Subjects-Con!
O c.
9
SURFACE
34.6 34.0
32.0
33.1
33.9
33.7 32.9
Bale
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8
ON BODY
to Thirty-One
0.8
33.8
34.8 34.4
32.3
33.6
33.6
34.2 34.2
to Twenty-Five
Data Relating
0.8
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OF ELEVEX
Data Bela&g
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TE:bfI'ERATUBE
13
193/
I24
.75/l 5
184,022
156/108 163/n 3
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177/l
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heart. disease.
heart
glomerulo heart
J-:nlarged heart
J,;lilarged
( ‘hronic: khl:irgerl
Ee3ent in1 liyperlension
Hypertension. Arteriosclerotic Hyperthyroidism
Hypwtennion
H~pertensiori. nephritis
-- - ..~_.-. ..--
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M. J. 315435 F. 43
I. H. 287756 F. 26
B. Q. 311888 F. 25
::,~21/44
E. C. 380212 F. 46
l/44
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L. H. 351566 F. 44
372.511 F. 25
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0. K. 368408 F. 38
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1/ 5/42
c. c. 311597 F. 44
3/44
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.~..
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184676 ?. 33
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11x
42
Ii0
30
33
33
82
39
71
32
37.31
37.23
38.20
Ri.92
37.08
37.64
37.47
37.53
37.35
37.38
37 . 2”Y
37.oti
34.17
33.87
34.25
33.85
33.Oli
32.71
:CL01
34.51
33.54
33.92
33.11
33.49
x.1
35.1)
34.5
35.0
32.2
:!5.1
34.4
3.T.l
35.9
:I-l.tj
94.5
34.9
32.7
35.1
34.8
35.0
35.5
35.0
35.t;
::4.x
32.3
35.1
34.5
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35.2
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34.1
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33.4
34.5
34.1
x3.1
33.1;
32.4
34.6
32.9
34.1
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33.2
::3.4
32.8
32.4
34.2
33.7
:13.7
34.9
34.1
34.4
33.3
32.9
35.Z
34.8
35.4
33.7
32.2
33.6
32.2
32.7
31.3
31.G
34.1
33.5
33.1
X.4
33.2
32.8
32.8
33.8
30.6
31.2
34 .i
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32.8
32.3
33.2
33.2
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31.2
3.3.6
31.6
34.4
34.3
32.1
31.7
2’1.1
31.2
34.7
32.0
.
182/‘116
1W;‘ll
184/l37
“W/132
169/l
177/l
221/1‘M
241/l%
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140/85
15O/‘lK
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I
1:
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I1
hypertcneion.
HyptLrteusive Einlin@
Ilylwt
It~rlri~fn.
1-:ulrtrgcd
Ilype~tcusion. Enlarged Rheumntic heart disease. ,stenos-is and jnsufficiency
Essential heart
Hypertension
.\rteriolar
hypertension.
Hypt~rl~*nsion. cephalopathy.
Ikential heart
Hypertcusion. sclerosis
heart
heart. Mitral
Enlarged
enheart
Enlarged
nephro-
L
with the @‘OUIJ of normal young adtilt,s, or in the peripheral blood fiow of t htl men of the hypertensive pou~t as ~ou~parcd with the women with il!.l’~~“tellsiorl. df~C?YXye XfXtcll l’r~t~rpcruf to‘{ .----7’11p ilVPXl$X ITf?till tcmpernii~rc for this hypertensive pat,ients was 37.27” (‘.. with a range of 36.68<’ (1. to 3S.29 i ‘.. while the average rectal temperature of normal young subjects was 36.79 3 ( ‘, with a range of 36.32” (‘. to 37.24’ (‘. ;1lthough on statistical analysis the cdif ference is not significant, the rectal temperature of hypertensive l~ticiits was higher than that of normal persons (ITal)le 1. Pig. 1 ) ; most of the h!.!rcrtcrlcts’q (Table I, F’ig. I). In short, Ihc foot. temprratur~. of hypertensive patients was slightl>- colder, bitt because of the wide flurtuations of the foot temperature in individuals (emotional effects, ct,c.) the clifference is not statistically significant. Tentperaturc of Z;“orehud.--The temperature of the forehead in hypcrtcnsive patients averaged 34.7’ C.. with a range of 32.2” C. to 35.7” C., as compare~l with an average of 34.4” C.. wit,h a range of 33.8” C. to 34.9” C, for the normal ~s1’0up’~ (Table I, E’ig. 1 ) . In short, the forehead was slightly warmer in hypcr tensive patients than in normal yoiin g subjects, but the difference is not statistirnlly significant. Tempmxtures of Llr’cus of the Bot11~ Considere? as fi’egiorjs.--When the temperature of the individual areas of the body are considered in relat,ion to each ot,her, it is seen that the temperature of the upper part, of the body, including the forehead (Area 1): upper chest (Area 2), and lower chest (L4rea 3)) is warmer in hypertensive than in normal subjects.‘” The temperature of the abdomen (Area 4): arm (Area 5), and hand (Area 7) is essentially the same The temperature of the lower in those with hypertension as in normal subjects. part of the body, including the forearm (Area 6), upper thigh (Area 81, lower thigh (Area 9). leg (Area. IO), and foot, (Area II), however, arc colder in the
STl?W’ART
ET
AL. :
BLOOD
FLOW
AND
TEMPERATURE
IS
IIPPERTEXSIOS
627
hypertensive subjects than in the normal subjects (Table I, Fig. 1). although these differences are not significant statistically, it appears more than chance that in both men and in women with hypertension the upper part of the body It would not be expected that the is warmer and the lower part is cooler. means should take such a precise arrangement if it were the result of chancr. The reduction in temperature of the lower part of the body is greater than the elevation of temperature of the upper part of the body, so that the nveragc of the weighted skin temperature is, on the whole, less in the hypertensive patients. Clo~l Y,.cssure.--The average of the blood pressures for this hypertensive :group was lS3,/121 (Table I). Yltlse E&e.-The average of the pulse rates of this hypertensive grollp was 76 per minute (Table I). &~a2 Ne2nboZic Kate.-The average of the basal metabolic rates of the group with hypertension was ~3 per cent, while that of the normal subjects was -5 per cent I* (Table I, Fig. 2).
PRE-OPERATIVE HYPERTENSIVES BASAL METABOLIC RATE
. . I
I %-30G
-;oo m=MAL
0 0
0 0
U~JC~OCC -ooo ---0 I I 0 -10 E
r‘=FEMALE
Fig.
Z.-In
this
flgure
is shown
0 a3 cm2
the scatter data are
us I
+I0
a 00
I
+20
00
+30
1 AVERAGE
FOR
MALES
0
AVERAGE
FOR
FEMALES
ii
AVERAGE
FOR
BOTH
of the basal metabolic shown in Fig. 1.
I
rates
I
+40%
GROUf% of the patients
whose
DISCUSSION
These observations show certain differences in the peripheral blood flow and rectal and skin temperatures of hypertensive subjects as compared with those of young normal subjects. We did not have a comparable mixed group of normal young men and women for comparison but have used the young male group on which observations have already been reported. On comparison of the male component of this group of hypertensives with the group of normal men, it was found that these show the same trends as in t!le average of the male and female hypertensive groups, but the differences were slightly less marked. The t,rend is for a lower peripheral blood flow in the hypertensive group than it1 normal subjects, that the hand (Area 7), abdomen (Area 4), and arm so. The room temperature of 27” C. was chosen in order to have vasodilatation present in each series. The rectal temperature was higher in the hypertensives
than in normal subjects. but the average \yeight& skin tetnperature was les+y. The hands were of the sarnc tcmperaturc in the hyl~ertcnsivc patients as in the normal persons, but the feet were colder. The foreheads of t,hc hypcrtcnsirc patients were slightly warrnclr than Ilormal, but the differcnc~e WIS IIOI. su 1'. ficicnt lo csplain the flush \\,hicxh lrypc~i+tcYjsiv,~patients csbihit clirliwll)*. It is sew that the upp~‘t* IGIH: of t11c bnd;v is W;IIWIAI’ it1 11yl)clrtwlsi\,tLtl~art in normal Slll)jPc*tS, tllill flI(s Ililrl~l j .\Y(‘il /i. it1~1l~~li~~~l1 (.Irca -1-i. illl(/ :IPIII (Area 5). IEIVC the saltle temperat-urc in hypertcnsivcb :III~ normal illflivitlual~ : and that the lowr part of the l~ody. inc*luding tllc I’olx~arrn (Area 6) , I.I[IIICI’ thigh (Area 81, lowc~’ i11igh (Arca !Jj, leg (Area 101, and foot (Arca 11)) is caolder than normal. 7%~ reduction iti tenrperaturc in the lower [‘art of I hc body is greater than th(: elevation 01’t6wrperatrrrc in 1.1~upper part. iIs :I VOIIsequence, the average \wighted skin 1emperature is colder in hylwxtellsivc~ pa tients than in normal srlh.jects when fho whole group is considered : for tbcmale group alone, however, the ave~xge skin temperature was the sanic as in tlw normal group. The warmw upper part indicates increased peripheral bloc~d flow to this part, the normal t,emperature of the middle part of the bot1.v illdicates an essentially normal amount. of blood flow in this area, and the wltl lower part of the body indicates a deercascd amount of blood allotted to thr> peripheral circulation in 11lis part. Reduction ill temperatlwc 01 iho colder part is so much more nlarkcd than the rise in tcmpcrainrc~ of the warmer part. taking into consideration wighting of dift’erent par& of the body, that the total amount of blood allotted to the whole periphery of the body is decreased as compared with a normal snb,jed. There appC!arS then to be vnsodilatafion in Ihc> upper part of the body a~~(1\-;lsoconstriction in thr ~OWPI*part. .\s a wt1sq’quencc, the skin cannot. dissipate tfficientl,v 1he inc:reascd amount, ot’ hc~af \)I’() tl~wd, and increased heat sforage and rise in rectal tempcraturc rtsull. Abramson and Fierst”’ found the resting blood flow to the fnrearm an(l leg of hvpcrtensive patient,s by the venous occlusion method was grcafcr while that in the hand was less than in a normal group they observccl. This method measures the total amount of blood going to that; part in cubic cent,imders p(lt’ minute per 100 cx. of limb volume. On the nt,!irr hantl, the methotl w-c have {Ised measures ihe average amount of blood allotted to the periphery of tbp whole body in cubic centimeters per square meter of I)ody surface per minute>. for a, depth of about 1 cm. l~clow the skin surface. Steele and Kirk’” in a stud? of nine hypertensive patients dicl not find any differcnw from 11ormalin the skin temperature ill the arcas from which t.ltey recorded the tcmperal we. Diff%rcnws in the gclleral pla11 aud tec~lmique of thr IIVO sets oI’ csperiments Init>- ;WCOUII~ for these differences : our patients were nude and remained basal tbroughoul the morning the observations were made: moreover the lar~r number of ]);Itients in our series may give a wider spwad of variation,<. In these patients with hypertension tbtt-c is a linc~lr correlation between peripheral blood flow and t,he average weighted skin t(~nlpctrature (Fig. ;3) since the higher average skin temperalures were associated with higher values for the peripheral blood flow. There was no demonstrable wrrelal-ion between periph-
against u liich.
Fig.
3.-In this the corresponding howc~vr~. is not
figure
the peripheral blood flows of all patients (Table average skin temperatures. h linear correlation as claw x.9 the correlation after ol~rmtiwr.~
is
1) nre plottad dt~monstmtcd,
It is of interest to compare the data relatin g to the male subjec:ts in this younger group of hypertensive patients with the hypcrtcnsive malt patients in the Iater decades. .22 The peripheral blood flow in the younger subjects was Eower than in the older ones but not significantly so statistically. The rectal and average weighted skin temperatures were 7Ggher in younger hypertensiw patients, but again the difference was not great enough to he sign&ant. TEth a few csccptions the temperatures for all the areas of the body were greater in the younger group of hypertensive patients. The exceptions were the temperatures of the hand (Area 7)) which were decreased, and of the lower thigh (Area 9‘1 anti leg (Area IO), which mere the same. The clifferences, however, were not significant. Although on statistical analysis the differences are not significant, t,hcrc is the pattern in which there appears to be a trend toward lower peripheral I)lood flow and greater rwtal and skin temperatures in young hypertensive pat icnts than in those with hypertension who rea.ch the later decades. Tn short,
the deviation from the normal is not as great in older individuals wit,h hypert,ension as in the younger hypertensive patients. Tt is of interest to compare thr measurements ill patients suffering from e,ssential hypert.ension with those made in patients in whom hypertension was LI consequence of coarctntion of the aorti~~~ The data in t,he two sets of observnLions are not strictly comparable, bccdause in the latter group observations were made at 25O C., while in the observat,ions no\v bein fi reported the room temperature was 27” (‘. ln the patients with coarctation of the aorta the average weighted skin and r&a.! temperatures were higher than t.hose in nc~rmxl subjwt s at 1he SRIIIP room tcmperaturca, and, morcovcr, the temperat,ures oi’ the skin of all the eleven areas of the body whirh were measured were higherr than those in normal subjects. The hypertension of coarctatiou of the aorta is associated wit,11 warm feel; and that. of cssent ial hypertension is associated with cool feet. The cardiac output in coarctation of the aorta is increased”” so that thcrc i?: available an increased amount of blood for allotment to t.he periphery 01’ the body. Starr and his associatesZ5 and StewarP have shown that in certain patients with hypertension without heart failure f.he cardiac output is within the normal range, while in others the cardiac output is decreased. Starr found that, those patients with the smaller cardiac output had smaller hearts than those with large outputs. In some, the cardiac output was smaller than that in subjects with normal hearts. This reduced cardiac output achieves the maintenance of hypertension without increase in the heart, ‘s basal work. Since measurements of cardiac output were not available in the group of patients we arc 110~ reporting, correlation with the trend toward decrease in periphera,l blood flow c:ould not be made. The manifestations of the high blood pressure of essential llypertension arc also different. from those in the hypertension of pheochromocytoma. In a patient suffering from such a tumor, observationsz7 pointed to marked generalized The peripheral blood flow was decreased even peripheral vasoconstriction. though the basal metabolic rate was +48 per cent which would be expected to increase the peripheral blood flow (Stewart and Evans**). The average weighted C.), and the temperature of the hands skin temperature was decreased (32.45” and feet was very cold (31.10” C. and 26.80” C., respectively). Because the body could not dissipate the increased amount of heat produced, there was heat storage and a high rectal temperature resulted. These observations indicate t,hat t,he elevation of arterial pressure in hypertensive individuals does not depend on constriction of the arterioles of the skin, subcutaneous tissue, and muscle to the depth of 1 cm. below the surface. Steele and Kirkyg arrived at a similar conclusion. While on the average the peripheral blood flow may be decreased in hypertension, there is no correlation between the peripheral blood flow and the level of blood pressure. Moreover, if t-he rise in blood pressure were dependent on surh vasoconstriction, which would presumably be generalized, it would be difficult to explain the tendency to increase in warmth of the upper part of the body and decrease in temperature of the lower part in hypertensive individuals. On bhe other hand, in the hyper-
ST!?\\-.\RT
P:T
,212. :
ISLOOD
PLOW
.\SD
TEBWERATURE
IS
IIYPERTESSIOS
631
tension of pl~eocl~roinoc~ton~a~~ in which there is reason to believe that there is vasoeonstriction due to the discharge of cpinephrine into the blood stream, the effects would bc expected to be generalized. In accord with this theory, we found” that flu2 skin in most parts of the body was colder than normal, wit’h a low averaye wrighted skin temperature and very fold forehead, hands, Icgs, and feet. The peripheral blood i-low and average skin and rectal temperatures have been measured under basal conditions in 56 patients suffering from arterial hyp,t~rtension. A modification of the method of I-Iardy and Soderstrom was used. Observations were made at an environmental temperature of 27” C. and 50 per cent humidity. 1. The average peripheral blood flop for the group is slightly decreased as Tompared with normal subjecls, but the difference does not appear to be statistically significant; the range is essentially the same as in normal subjects. 2. The rectal temperature is higher than in normal subjects, the temperature being over 37” C. in most hypertensive subjects and under 37” C. in the normal control group. 3. The average weighted skin temperature is lower than that in normal subjects, but the difference is not significant statistically. 4. In hypertensive patients the temperature is higher than normal in the upper part of the body, is near the normal level in the middle part of the body, and is cooler than normal in bhe lower part, especially in the fed. 5. There were no significant differences between the peripheral blood flow or rectal or skin temperatures of t,he men and those of the women with hypertension. 6. The level of the peripheral blood flow is unrelated t,o the level of the systolic or diastolic blood pressure in individual patients, and a linear correlation between peripheral bIood flow and blood pressure level was not apparent. 7. In these patients with hypertension there wa.s a, linear correlation between the level of peripheral blood flow and the average weighted skin temperature, in that the higher the skin t,emperature the higher the peripheral blood flow. 8. The basal metabolic rate in hypertensive patients is within the normal range. 9. The hypertension of patients observed in this study exhibits different characteristics from those prevailing in coarctation of the aorta and in pheochromocytoma, in which the local skin temperatures are. respectively, warmer and cooler than normal. REFERENCYS AL 1. Goldblntt, H., Lynch, J., Hanzal, R. F., and Summerville, W. \V. : Studies on Experimental Hypertension. I. The Production of Persistent Elevation of Systolic Blood Pressure by Means of Renal Ischemia, J. Exper. Ned. 59: 347, 1934. 2. Goldblatt, H.: Studies on Experimental Hypertension. V. The Pathogenesis of Experimental Hypertension Due to Renal Ischemia, Ann. Int. Med. 11: 69, 1937. 3. Page, I. H.: Studies on the Mechanism of Arterial Hypertension. J. A. U. A. 129: 75:. 1942.
of’ Hypertension. I. H.: Special Aspects of the Problem of tile Rena). Origin Bull. New York hcad. Med. 19: %I, 1943. The Imect of s:planchnll~ Btewart, H. J., Evans, W. F., Haxkell, H. S., and Brown, H.: Resection on the Peripheral Blood Flow. Rectal and Skin TempCraturPs in Hypcr tension, AX. IIE:ART J.- (In prtrss. 1 ~‘:lrtleman, B., and Smithwick, Ii. H.: ‘I’IIC Rcjation of Vascular Disease to the Hyper tensive State Based on a Study of Renal Bilrlwies From One HundrPd Hyper tensive Patients. J. A. RI. A. 121: 1256. l!M. ‘I’albott, J. H., Cast&man, B., Smithwick,’ II. H., .Ilelville, JC t;., and P’ecora, 1,. .I.: Renal Biopsv Studies Correlated With Renal (.‘learance Ol)servations in Byper tensivr Pati’ents Treated 1)~ Ii:t,lic:tI R,vmpathwtr,my, J. (‘lin. Investigation 22: 387. 1943. The Peripheral Resist:+nc*lt it] I’ersistcut Arterial II,vlwrtcnsi~ln. Pickering, B. W.: Clin. SC. 2: 209, 1936. The Sature of the l’eripheral Besista.nce in Arterial Prinzmetal, M., and Wilson? (‘.: Hvnertension With Special 1~efcr~111~~~ to the \~arr~ruot,or R\-stem, .l. C’lin. Tn Page,
Heat I.OCS From the Xude Body and Peripheral .r: 11.: and Sodcrrtrom. C+. F.: Blood Flow at, Temperatures of 2L” (‘. to 35” C.. J. Nutrition 16: 493, 7938. Roth, P.: Modifications of Apparatus and Improved Technique Adaptable to the Benedict Type of Respiration Apparatus, Boston M. & 8. J. 186: 457. 1922. Boothby, IV’. M., Berkson, J., and Dunn, H. L.: Studies of the Energy of Metabolism A Rtnndard for Basal Metabolism With a Nomofran~ of Normal Individuals: for Clinical Application, Am. J. Physiol. 116: 468, lRS6. DuBois, D.? and DuBois, E. F’.: A Formula to Estimate Spproximate Surfai,r: Area i I’ Height and Weight Be Known, Awh. Int. Med. 17: 863, 1916. ‘l’hf~ l~:ffect of Smoking C’igaref ttas or, 1 llts I’erillll I*;\-am, W. F and Stewart, H. J.: era1 BloGd Flow, AM. HEaRT J. 26: 98, 1943. Stewa~tz H. .T.. and Evans. W. E’.: The Peripheral Blood Flow Under Basal (:OIIdlt~ons in Normal lRlnlc Rul>jwt - iit the Third Dc~*ade. Ax. HEART .T. 26: 67. 19-G. Steele, ,J. Jr., and Kirk, E.: The Siguilicanee of the \‘e.+r~ls of the Skin in Essenti:l I Hypcrtcnsion, AM. HI<.\EX~ J. 13: X95. 19%. Stewart, H. J., and Jack, ,1’. H.: The Pa>:11 I!letul,llli(~ Rate in Organic Heart Disease. AM. HEART J. 19: 738, 19-t(i. Shapiro, S.: The nasal 1\Ietabolic: Hate in (‘ases of Chronic, ( ‘ardin(~ Disease arid irr Cases of HGypertension, Brch. Int. Med. 38: 385, 1926. Rteyvart! H. J., Evans, WV. F’., and Haskell, H. Fc.: The Peripheral Lllrlo~l l”lorv I;nrlt~~ Basal Conditions in Older Male Subjrcts With Normal and Elevated Blood Pressures. Anr. HEART 5. 31: 343, 1946. Stewart. H. J.. Hankcll. H. R,. and Evany \V. E‘.: ‘The Peripheral Blood Flow and Other Observations in (‘oarcation of the rlorta, AM. HEAR? J. 28: 217, 1944. Stewart, H. J., and ISaile)~, R. T,.: Thr> Cardiac Output and Other Measurements of the Circulation in Coxrctxtion IIf the Aorta. .J. Clin. Investigation 20: 145! 1941. Starr, I., Donal, J. R., Bixrgolicy, A.. Yhaw. H., (~!ollins. L. H.. and Gamble, C’. .J.: Studies of the Heart and Circulation in Disease; Estimations of Basal Cardiac in -035 Subjects. .T. CJin. Tn Output, Metabolism, Reart Size. and Rloo~l Pressure \-estigation 13: 561, 1934. Unpublishe~l observntiorlh. ,Strwwt, H. J.: Evans, W. F., and Stewart, H. J.: Thr P~~rij~ht~ral Hlood E’low it1 a (‘atie of A~lrrnai and .4ftcr Operation. AM. HEART .T. 24: 53.5, 1949. Pheochromoc~-t oma T+fore Rlwd Finnin ~~~l)crtll~-r~)i~lis~ll. Stewart, H. J., a’utl F ra II :, IV. I”. : ‘l’h~! PeriphPr:ll Hardy,
i\ar.
HURT
J. 20:
71.7.
‘19&n.
1113 sulJ,ject of hypertension has engaped the attention of man!. investiq~~toi~~ in recent years. St~imulus was given lo tlww investigations I~,I. tlw ttslwriwents of Goldblatt and his associates relating to tlw rise ill 1~100~1l)wssut-e whic.11 I’ollows the preparation of an iwhemic kidnq-” ” and ty.- the studies 01’ I'iig~'~~ ' I'('lating to the chemical background of hylwrtension. The s\qit~nl t watment ~1 hypertension, which has also increased the intrrcst in anal stlllly ~)t’ thiq $II~I.iwt, will he discussed in a succeeding pal~ir.‘,
Pickering;’ found the rate of 1~100~1HOIV through the i’orca~~n in t1ylwrtc~nsi\.(~ sui)jects the same as t,hat in subjects with normal l)lood pressure ant1 wn~litd(~ti that, owing to \asoconstriction, the resistance oRwed by the resscls oi the i‘~w a 1x1 is increased in hypertcnsiun. ~‘rinzilletal aild ~~ilS(JIl” ah i’(JUll~l t/lilt thi wstiug blood flow in the arm \vas within norm;11 limits and wic~lri~l~~~l that increased vascular resistance is not confined to the splanchnic aw;l \Jlit is ,gm chralizetl t~hroughout the systemic circulation. Abramson and I;liet.st.l” using tilt, venms occlusion plethpsmographic method, found that the resting ~~1o1.d f f o\: through the arm and leg was significantly great,er? IJU~ that thro~~gh tlic, hand uxs 1~s in hypertensive subjects than in normal snhjects. They wn~Iuclcd that t iirir observations directly contradicted the prevailing theory that there is ~II c~r:rlized and uniformly increased periphwnl rcsislarice in hypertension. ( )ne of the results of t.hcse studies has IKY~II the acwunnlation Of’ :I \-;wt atnaltrlt of literature which has contributed much to the understanding ol’ hypeI.tension. However, the mechanism of hypert,ension, whether it is of nerwus 01 tiun1wal origin, still remains unexplained. It appeared to us that a study oi the total peripheral blood fiow in essential hypertension might 1~ OFinietw~ in supported twwi\
by wl
for
a grant publication
from the John and Aug. 2, 1945.
Mary
R.
?darkle
Foundation
the whole general problem as there are ~~~J1lfiiCtill,01 vi,,,, abtrut, the ~)lC,Oll ilo\\ in local areas. We have accordingly- measurttl the amomll oi’ I~10011 all01 1~1110 the peripheral circulation in 1Jaticnts sui’f&il;: from cssenliill h~~!wl*l msiol!. IJ:lIWl t]lC C:i’fWl ‘. These observations form the basis oi’ this report. II1 all(JthC!l’ on the peripheral blood flow cd’ spli~n(~h~~i~ resection I’or the loc~ring 01’ IJ~~JW~ pressure will be appraised.” Sixty-nine observations were made on 56 patients who had aH(t,.iiII II~~J(,I~tension ; 25 were men, and 31 w(‘r( wonicn. The ages r;rngtd Prom ICI to 66 years. The peripheral blood flow wa.s measured by our moclification”~ I2 of thcl method of Hardy and Soderstrom.‘” Hardy and Soderstrom have shown that. a,t a t,emperature below 28” C., the skin fun&ions like a dead insulator when the sub,ject is lying nude in the basal state, and that blood flow to the skin, thermal conductivity of the peripheral tissues, and vaporization are constant and minimum. With an increase in blood flow to the periphery, more heat, is brought from the deeper tissue to t,he surface. This increases lhe thermal eonductanc~c of the superficial tissues; therefore, changes in thermal conductance become an index of peripheral blood flow. With this met,hod, blood flow is expressed as a function of heat loss. surface area7 c&cel*cJyeweiglltcNd sluh fenzpernt~rtm, ant1 rectal temperature. The method requires the recording of skin and rectal temperature13 at known intervals, oxygen consumption,‘4 height, and body weight.‘Zl lri The skin temperatures were recorded with a Hardy-Sodcrstront radiometeP from eleven points on t,hc anterior surface of the body as shown in Fig. 1. With this method the amount of blood allocated to the whole periphery of the body is measured, rather than the flow in local areas, a.nd may 1)~ c~sp~~srctl in cubic centimeters per square meter of body surface per minute. E%?L of Proced~cre.-The plan of procedure was that described in recent publications.‘*~ li All measurements wcrc carried out in the morning beforcb breakfast with the patients in a basal metabolic state. They were brought 111 the constant temperature room and allowed to lie in bed nude, covered onI\, with a sheet. One hour was allowed for ad,@stment to the room temperat,urc Measurements of skin and rectal tc.mperaof 27” C. and 50 per cent humidity. tures were made at twenty-minute intervals. Each set of observations covere(I a period of sixty to one hundred minutes. Blood pressure and pulse rate w;~r~’ recorded between temperature readings. The basal metabolic rate was mcasurrtl at the beginning and again at the end of the morning’s observations. Four to six set,sof skin and rectal tcmpcrntures ncre recorded from which three to five estimations of peripheral blood flow could be made fog the morninir. The data recorded in Tal~lc I for each date show the avcragcs of the pcriphc~;xl blood flows, temperatures, blood pressures, and heart rat-es for the morning.
The results of the observations are shown in Table 1 and E’ig. 1. Blood Flow.-The average peripheral blood flow of the whole group was 5’1 CL per square meter of body surface per minute, as compared
Periphel*al
with 73 C.C. per square meter per minute for a group of normal young male suhjects’Y at the same room temperature (Table I, Fig. 1). While the periphrrnl blood flow is statistically significant in the g-ro11p of normal young adults, the fluctuations in the hypertensive groups are such that the dif?erence from the young; normal ma!c group is not significant. There was no significant clifferww in t IIt) peripheral blood flow in the men of the hypcrtensire group as wnipared
:X3:lSS32Id aoo'm
2 c 4 =
.’ ‘C i
,
4/’ 5/44
‘. K. 38001 t. 51
E. ‘5575 56
2/10/44
verage-men verage age = 36 yr. ;andard deviations about the means
X/16/43 3/22/43
121 3/43
. McD. 5209 r. 48
. L. i1331 :. 31
z/10/44
:. L. 76206 1. 19
5/44 7/44
1/ 1/
75325 4. 48
v. c.
I
33.1X
*,... .).I ,- I
37.11;
yf;,L’;{
0.60
0.24
54
1%
33.74
37.27
61
34.89 34.51
32.25
33.52
33.97
34.30 33.97
37.36 37.11
36.94
37.11
36.81
37.27 37.10
136 108
25
25
81
62 70
^-
-
-
:%.i
34.z’
0.7
34.8
35.6 35.4
34.4
34.9
34.7
Z-1-.1
34.1
0.6
34.7
35.3 35.0
34.3
33.5
34.7
35.1 34.8
0 c.
o c.
35.3 35.0
2
1 0 c.
4
22.9
34.3
0.8
34.3
35.0 34.7
32.8
33.7
34.4
34.5 34.3
0.7
34.1
34.9 34.5
33.4
33.9
33.9
34.4 33.4
32.S
33.7
X.9
34.3
o c.
ti
ARE-IS
o c.
7
1.0
34.5
35.3 35.1
32.7
34.2
35.1
35.0 34.8
33.0
33.2
34.6
34.0
32.0
32.9
* c!.
11
1.0
32.5
33.7 33.”
30.2
32.0
32.5
33.2 33.9
1.7
32.1
34.4 34.4
31..5
32.5
33.4
34.4 34.5
3O-. 8
33.2
.72 .LS
33.2
3:t.S
33.3
Female Subjects
1.1
32.8
33.4
30.1
32.2
33.3
33.5 33.2
34.7 34.4
0.9
a c.
10
Subjects-Con!
O c.
9
SURFACE
34.6 34.0
32.0
33.1
33.9
33.7 32.9
Bale
a c.
8
ON BODY
to Thirty-One
0.8
33.8
34.8 34.4
32.3
33.6
33.6
34.2 34.2
to Twenty-Five
Data Relating
0.8
34.4
35.1 35.0
32.2
33.5
34.6
34.7 34.3
o c.
5
OF ELEVEX
Data Bela&g
o c.
3
TE:bfI'ERATUBE
13
193/
I24
.75/l 5
184,022
156/108 163/n 3
x3/121
177/l
11
heart. disease.
heart
glomerulo heart
J-:nlarged heart
J,;lilarged
( ‘hronic: khl:irgerl
Ee3ent in1 liyperlension
Hypertension. Arteriosclerotic Hyperthyroidism
Hypwtennion
H~pertensiori. nephritis
-- - ..~_.-. ..--
~.
2/27/42
I/
4/11/4-k
11/10/41
9. A. 318945 F. 41
M. J. 315435 F. 43
I. H. 287756 F. 26
B. Q. 311888 F. 25
::,~21/44
E. C. 380212 F. 46
l/44
“/
i/J3
L. H. 351566 F. 44
372.511 F. 25
It’/
l/13/44
0. K. 368408 F. 38
c. D.
1/ 5/42
c. c. 311597 F. 44
3/44
5/31/44
5/27/44
s/29/44
.~..
2. N. CL46907 F. 42
184676 ?. 33
3.c.
d. D. 884959 7. 4G
11x
42
Ii0
30
33
33
82
39
71
32
37.31
37.23
38.20
Ri.92
37.08
37.64
37.47
37.53
37.35
37.38
37 . 2”Y
37.oti
34.17
33.87
34.25
33.85
33.Oli
32.71
:CL01
34.51
33.54
33.92
33.11
33.49
x.1
35.1)
34.5
35.0
32.2
:!5.1
34.4
3.T.l
35.9
:I-l.tj
94.5
34.9
32.7
35.1
34.8
35.0
35.5
35.0
35.t;
::4.x
32.3
35.1
34.5
.x.9
35.2
34.4.
34.1
:x.2
3!!.4
35.z
34.i
33.4
34.5
34.1
x3.1
33.1;
32.4
34.6
32.9
34.1
?J.:!
33.2
::3.4
32.8
32.4
34.2
33.7
:13.7
34.9
34.1
34.4
33.3
32.9
35.Z
34.8
35.4
33.7
32.2
33.6
32.2
32.7
31.3
31.G
34.1
33.5
33.1
X.4
33.2
32.8
32.8
33.8
30.6
31.2
34 .i
32.1
32.8
32.3
33.2
33.2
3lJ.l)
31.2
3.3.6
31.6
34.4
34.3
32.1
31.7
2’1.1
31.2
34.7
32.0
.
182/‘116
1W;‘ll
184/l37
“W/132
169/l
177/l
221/1‘M
241/l%
xox/11t’,
140/85
15O/‘lK
17”/110
I
1:
11;
.
+
IL!
.)
10
1
-i
I1
hypertcneion.
HyptLrteusive Einlin@
Ilylwt
It~rlri~fn.
1-:ulrtrgcd
Ilype~tcusion. Enlarged Rheumntic heart disease. ,stenos-is and jnsufficiency
Essential heart
Hypertension
.\rteriolar
hypertension.
Hypt~rl~*nsion. cephalopathy.
Ikential heart
Hypertcusion. sclerosis
heart
heart. Mitral
Enlarged
enheart
Enlarged
nephro-
L
with the @‘OUIJ of normal young adtilt,s, or in the peripheral blood fiow of t htl men of the hypertensive pou~t as ~ou~parcd with the women with il!.l’~~“tellsiorl. df~C?YXye XfXtcll l’r~t~rpcruf to‘{ .----7’11p ilVPXl$X ITf?till tcmpernii~rc for this hypertensive pat,ients was 37.27” (‘.. with a range of 36.68<’ (1. to 3S.29 i ‘.. while the average rectal temperature of normal young subjects was 36.79 3 ( ‘, with a range of 36.32” (‘. to 37.24’ (‘. ;1lthough on statistical analysis the cdif ference is not significant, the rectal temperature of hypertensive l~ticiits was higher than that of normal persons (ITal)le 1. Pig. 1 ) ; most of the h!.!rcrtcrl
STl?W’ART
ET
AL. :
BLOOD
FLOW
AND
TEMPERATURE
IS
IIPPERTEXSIOS
627
hypertensive subjects than in the normal subjects (Table I, Fig. 1). although these differences are not significant statistically, it appears more than chance that in both men and in women with hypertension the upper part of the body It would not be expected that the is warmer and the lower part is cooler. means should take such a precise arrangement if it were the result of chancr. The reduction in temperature of the lower part of the body is greater than the elevation of temperature of the upper part of the body, so that the nveragc of the weighted skin temperature is, on the whole, less in the hypertensive patients. Clo~l Y,.cssure.--The average of the blood pressures for this hypertensive :group was lS3,/121 (Table I). Yltlse E&e.-The average of the pulse rates of this hypertensive grollp was 76 per minute (Table I). &~a2 Ne2nboZic Kate.-The average of the basal metabolic rates of the group with hypertension was ~3 per cent, while that of the normal subjects was -5 per cent I* (Table I, Fig. 2).
PRE-OPERATIVE HYPERTENSIVES BASAL METABOLIC RATE
. . I
I %-30G
-;oo m=MAL
0 0
0 0
U~JC~OCC -ooo ---0 I I 0 -10 E
r‘=FEMALE
Fig.
Z.-In
this
flgure
is shown
0 a3 cm2
the scatter data are
us I
+I0
a 00
I
+20
00
+30
1 AVERAGE
FOR
MALES
0
AVERAGE
FOR
FEMALES
ii
AVERAGE
FOR
BOTH
of the basal metabolic shown in Fig. 1.
I
rates
I
+40%
GROUf% of the patients
whose
DISCUSSION
These observations show certain differences in the peripheral blood flow and rectal and skin temperatures of hypertensive subjects as compared with those of young normal subjects. We did not have a comparable mixed group of normal young men and women for comparison but have used the young male group on which observations have already been reported. On comparison of the male component of this group of hypertensives with the group of normal men, it was found that these show the same trends as in t!le average of the male and female hypertensive groups, but the differences were slightly less marked. The t,rend is for a lower peripheral blood flow in the hypertensive group than it1 normal subjects, that the hand (Area 7), abdomen (Area 4), and arm so. The room temperature of 27” C. was chosen in order to have vasodilatation present in each series. The rectal temperature was higher in the hypertensives
than in normal subjects. but the average \yeight& skin tetnperature was les+y. The hands were of the sarnc tcmperaturc in the hyl~ertcnsivc patients as in the normal persons, but the feet were colder. The foreheads of t,hc hypcrtcnsirc patients were slightly warrnclr than Ilormal, but the differcnc~e WIS IIOI. su 1'. ficicnt lo csplain the flush \\,hicxh lrypc~i+tcYjsiv,~patients csbihit clirliwll)*. It is sew that the upp~‘t* IGIH: of t11c bnd;v is W;IIWIAI’ it1 11yl)clrtwlsi\,tLtl~art in normal Slll)jPc*tS, tllill flI(s Ililrl~l j .\Y(‘il /i. it1~1l~~li~~~l1 (.Irca -1-i. illl(/ :IPIII (Area 5). IEIVC the saltle temperat-urc in hypertcnsivcb :III~ normal illflivitlual~ : and that the lowr part of the l~ody. inc*luding tllc I’olx~arrn (Area 6) , I.I[IIICI’ thigh (Area 81, lowc~’ i11igh (Arca !Jj, leg (Area 101, and foot (Arca 11)) is caolder than normal. 7%~ reduction iti tenrperaturc in the lower [‘art of I hc body is greater than th(: elevation 01’t6wrperatrrrc in 1.1~upper part. iIs :I VOIIsequence, the average \wighted skin 1emperature is colder in hylwxtellsivc~ pa tients than in normal srlh.jects when fho whole group is considered : for tbcmale group alone, however, the ave~xge skin temperature was the sanic as in tlw normal group. The warmw upper part indicates increased peripheral bloc~d flow to this part, the normal t,emperature of the middle part of the bot1.v illdicates an essentially normal amount. of blood flow in this area, and the wltl lower part of the body indicates a deercascd amount of blood allotted to thr> peripheral circulation in 11lis part. Reduction ill temperatlwc 01 iho colder part is so much more nlarkcd than the rise in tcmpcrainrc~ of the warmer part. taking into consideration wighting of dift’erent par& of the body, that the total amount of blood allotted to the whole periphery of the body is decreased as compared with a normal snb,jed. There appC!arS then to be vnsodilatafion in Ihc> upper part of the body a~~(1\-;lsoconstriction in thr ~OWPI*part. .\s a wt1sq’quencc, the skin cannot. dissipate tfficientl,v 1he inc:reascd amount, ot’ hc~af \)I’() tl~wd, and increased heat sforage and rise in rectal tempcraturc rtsull. Abramson and Fierst”’ found the resting blood flow to the fnrearm an(l leg of hvpcrtensive patient,s by the venous occlusion method was grcafcr while that in the hand was less than in a normal group they observccl. This method measures the total amount of blood going to that; part in cubic cent,imders p(lt’ minute per 100 cx. of limb volume. On the nt,!irr hantl, the methotl w-c have {Ised measures ihe average amount of blood allotted to the periphery of tbp whole body in cubic centimeters per square meter of I)ody surface per minute>. for a, depth of about 1 cm. l~clow the skin surface. Steele and Kirk’” in a stud? of nine hypertensive patients dicl not find any differcnw from 11ormalin the skin temperature ill the arcas from which t.ltey recorded the tcmperal we. Diff%rcnws in the gclleral pla11 aud tec~lmique of thr IIVO sets oI’ csperiments Init>- ;WCOUII~ for these differences : our patients were nude and remained basal tbroughoul the morning the observations were made: moreover the lar~r number of ]);Itients in our series may give a wider spwad of variation,<. In these patients with hypertension tbtt-c is a linc~lr correlation between peripheral blood flow and t,he average weighted skin t(~nlpctrature (Fig. ;3) since the higher average skin temperalures were associated with higher values for the peripheral blood flow. There was no demonstrable wrrelal-ion between periph-
against u liich.
Fig.
3.-In this the corresponding howc~vr~. is not
figure
the peripheral blood flows of all patients (Table average skin temperatures. h linear correlation as claw x.9 the correlation after ol~rmtiwr.~
is
1) nre plottad dt~monstmtcd,
It is of interest to compare the data relatin g to the male subjec:ts in this younger group of hypertensive patients with the hypcrtcnsive malt patients in the Iater decades. .22 The peripheral blood flow in the younger subjects was Eower than in the older ones but not significantly so statistically. The rectal and average weighted skin temperatures were 7Ggher in younger hypertensiw patients, but again the difference was not great enough to he sign&ant. TEth a few csccptions the temperatures for all the areas of the body were greater in the younger group of hypertensive patients. The exceptions were the temperatures of the hand (Area 7)) which were decreased, and of the lower thigh (Area 9‘1 anti leg (Area IO), which mere the same. The clifferences, however, were not significant. Although on statistical analysis the differences are not significant, t,hcrc is the pattern in which there appears to be a trend toward lower peripheral I)lood flow and greater rwtal and skin temperatures in young hypertensive pat icnts than in those with hypertension who rea.ch the later decades. Tn short,
the deviation from the normal is not as great in older individuals wit,h hypert,ension as in the younger hypertensive patients. Tt is of interest to compare thr measurements ill patients suffering from e,ssential hypert.ension with those made in patients in whom hypertension was LI consequence of coarctntion of the aorti~~~ The data in t,he two sets of observnLions are not strictly comparable, bccdause in the latter group observations were made at 25O C., while in the observat,ions no\v bein fi reported the room temperature was 27” (‘. ln the patients with coarctation of the aorta the average weighted skin and r&a.! temperatures were higher than t.hose in nc~rmxl subjwt s at 1he SRIIIP room tcmperaturca, and, morcovcr, the temperat,ures oi’ the skin of all the eleven areas of the body whirh were measured were higherr than those in normal subjects. The hypertension of coarctatiou of the aorta is associated wit,11 warm feel; and that. of cssent ial hypertension is associated with cool feet. The cardiac output in coarctation of the aorta is increased”” so that thcrc i?: available an increased amount of blood for allotment to t.he periphery 01’ the body. Starr and his associatesZ5 and StewarP have shown that in certain patients with hypertension without heart failure f.he cardiac output is within the normal range, while in others the cardiac output is decreased. Starr found that, those patients with the smaller cardiac output had smaller hearts than those with large outputs. In some, the cardiac output was smaller than that in subjects with normal hearts. This reduced cardiac output achieves the maintenance of hypertension without increase in the heart, ‘s basal work. Since measurements of cardiac output were not available in the group of patients we arc 110~ reporting, correlation with the trend toward decrease in periphera,l blood flow c:ould not be made. The manifestations of the high blood pressure of essential llypertension arc also different. from those in the hypertension of pheochromocytoma. In a patient suffering from such a tumor, observationsz7 pointed to marked generalized The peripheral blood flow was decreased even peripheral vasoconstriction. though the basal metabolic rate was +48 per cent which would be expected to increase the peripheral blood flow (Stewart and Evans**). The average weighted C.), and the temperature of the hands skin temperature was decreased (32.45” and feet was very cold (31.10” C. and 26.80” C., respectively). Because the body could not dissipate the increased amount of heat produced, there was heat storage and a high rectal temperature resulted. These observations indicate t,hat t,he elevation of arterial pressure in hypertensive individuals does not depend on constriction of the arterioles of the skin, subcutaneous tissue, and muscle to the depth of 1 cm. below the surface. Steele and Kirkyg arrived at a similar conclusion. While on the average the peripheral blood flow may be decreased in hypertension, there is no correlation between the peripheral blood flow and the level of blood pressure. Moreover, if t-he rise in blood pressure were dependent on surh vasoconstriction, which would presumably be generalized, it would be difficult to explain the tendency to increase in warmth of the upper part of the body and decrease in temperature of the lower part in hypertensive individuals. On bhe other hand, in the hyper-
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tension of pl~eocl~roinoc~ton~a~~ in which there is reason to believe that there is vasoeonstriction due to the discharge of cpinephrine into the blood stream, the effects would bc expected to be generalized. In accord with this theory, we found” that flu2 skin in most parts of the body was colder than normal, wit’h a low averaye wrighted skin temperature and very fold forehead, hands, Icgs, and feet. The peripheral blood i-low and average skin and rectal temperatures have been measured under basal conditions in 56 patients suffering from arterial hyp,t~rtension. A modification of the method of I-Iardy and Soderstrom was used. Observations were made at an environmental temperature of 27” C. and 50 per cent humidity. 1. The average peripheral blood flop for the group is slightly decreased as Tompared with normal subjecls, but the difference does not appear to be statistically significant; the range is essentially the same as in normal subjects. 2. The rectal temperature is higher than in normal subjects, the temperature being over 37” C. in most hypertensive subjects and under 37” C. in the normal control group. 3. The average weighted skin temperature is lower than that in normal subjects, but the difference is not significant statistically. 4. In hypertensive patients the temperature is higher than normal in the upper part of the body, is near the normal level in the middle part of the body, and is cooler than normal in bhe lower part, especially in the fed. 5. There were no significant differences between the peripheral blood flow or rectal or skin temperatures of t,he men and those of the women with hypertension. 6. The level of the peripheral blood flow is unrelated t,o the level of the systolic or diastolic blood pressure in individual patients, and a linear correlation between peripheral bIood flow and blood pressure level was not apparent. 7. In these patients with hypertension there wa.s a, linear correlation between the level of peripheral blood flow and the average weighted skin temperature, in that the higher the skin t,emperature the higher the peripheral blood flow. 8. The basal metabolic rate in hypertensive patients is within the normal range. 9. The hypertension of patients observed in this study exhibits different characteristics from those prevailing in coarctation of the aorta and in pheochromocytoma, in which the local skin temperatures are. respectively, warmer and cooler than normal. REFERENCYS AL 1. Goldblntt, H., Lynch, J., Hanzal, R. F., and Summerville, W. \V. : Studies on Experimental Hypertension. I. The Production of Persistent Elevation of Systolic Blood Pressure by Means of Renal Ischemia, J. Exper. Ned. 59: 347, 1934. 2. Goldblatt, H.: Studies on Experimental Hypertension. V. The Pathogenesis of Experimental Hypertension Due to Renal Ischemia, Ann. Int. Med. 11: 69, 1937. 3. Page, I. H.: Studies on the Mechanism of Arterial Hypertension. J. A. U. A. 129: 75:. 1942.
of’ Hypertension. I. H.: Special Aspects of the Problem of tile Rena). Origin Bull. New York hcad. Med. 19: %I, 1943. The Imect of s:planchnll~ Btewart, H. J., Evans, W. F., Haxkell, H. S., and Brown, H.: Resection on the Peripheral Blood Flow. Rectal and Skin TempCraturPs in Hypcr tension, AX. IIE:ART J.- (In prtrss. 1 ~‘:lrtleman, B., and Smithwick, Ii. H.: ‘I’IIC Rcjation of Vascular Disease to the Hyper tensive State Based on a Study of Renal Bilrlwies From One HundrPd Hyper tensive Patients. J. A. RI. A. 121: 1256. l!M. ‘I’albott, J. H., Cast&man, B., Smithwick,’ II. H., .Ilelville, JC t;., and P’ecora, 1,. .I.: Renal Biopsv Studies Correlated With Renal (.‘learance Ol)servations in Byper tensivr Pati’ents Treated 1)~ Ii:t,lic:tI R,vmpathwtr,my, J. (‘lin. Investigation 22: 387. 1943. The Peripheral Resist:+nc*lt it] I’ersistcut Arterial II,vlwrtcnsi~ln. Pickering, B. W.: Clin. SC. 2: 209, 1936. The Sature of the l’eripheral Besista.nce in Arterial Prinzmetal, M., and Wilson? (‘.: Hvnertension With Special 1~efcr~111~~~ to the \~arr~ruot,or R\-stem, .l. C’lin. Tn Page,
Heat I.OCS From the Xude Body and Peripheral .r: 11.: and Sodcrrtrom. C+. F.: Blood Flow at, Temperatures of 2L” (‘. to 35” C.. J. Nutrition 16: 493, 7938. Roth, P.: Modifications of Apparatus and Improved Technique Adaptable to the Benedict Type of Respiration Apparatus, Boston M. & 8. J. 186: 457. 1922. Boothby, IV’. M., Berkson, J., and Dunn, H. L.: Studies of the Energy of Metabolism A Rtnndard for Basal Metabolism With a Nomofran~ of Normal Individuals: for Clinical Application, Am. J. Physiol. 116: 468, lRS6. DuBois, D.? and DuBois, E. F’.: A Formula to Estimate Spproximate Surfai,r: Area i I’ Height and Weight Be Known, Awh. Int. Med. 17: 863, 1916. ‘l’hf~ l~:ffect of Smoking C’igaref ttas or, 1 llts I’erillll I*;\-am, W. F and Stewart, H. J.: era1 BloGd Flow, AM. HEaRT J. 26: 98, 1943. Stewa~tz H. .T.. and Evans. W. E’.: The Peripheral Blood Flow Under Basal (:OIIdlt~ons in Normal lRlnlc Rul>jwt - iit the Third Dc~*ade. Ax. HEART .T. 26: 67. 19-G. Steele, ,J. Jr., and Kirk, E.: The Siguilicanee of the \‘e.+r~ls of the Skin in Essenti:l I Hypcrtcnsion, AM. HI<.\EX~ J. 13: X95. 19%. Stewart, H. J., and Jack, ,1’. H.: The Pa>:11 I!letul,llli(~ Rate in Organic Heart Disease. AM. HEART J. 19: 738, 19-t(i. Shapiro, S.: The nasal 1\Ietabolic: Hate in (‘ases of Chronic, ( ‘ardin(~ Disease arid irr Cases of HGypertension, Brch. Int. Med. 38: 385, 1926. Rteyvart! H. J., Evans, WV. F’., and Haskell, H. Fc.: The Peripheral Lllrlo~l l”lorv I;nrlt~~ Basal Conditions in Older Male Subjrcts With Normal and Elevated Blood Pressures. Anr. HEART 5. 31: 343, 1946. Stewart. H. J.. Hankcll. H. R,. and Evany \V. E‘.: ‘The Peripheral Blood Flow and Other Observations in (‘oarcation of the rlorta, AM. HEAR? J. 28: 217, 1944. Stewart, H. J., and ISaile)~, R. T,.: Thr> Cardiac Output and Other Measurements of the Circulation in Coxrctxtion IIf the Aorta. .J. Clin. Investigation 20: 145! 1941. Starr, I., Donal, J. R., Bixrgolicy, A.. Yhaw. H., (~!ollins. L. H.. and Gamble, C’. .J.: Studies of the Heart and Circulation in Disease; Estimations of Basal Cardiac in -035 Subjects. .T. CJin. Tn Output, Metabolism, Reart Size. and Rloo~l Pressure \-estigation 13: 561, 1934. Unpublishe~l observntiorlh. ,Strwwt, H. J.: Evans, W. F., and Stewart, H. J.: Thr P~~rij~ht~ral Hlood E’low it1 a (‘atie of A~lrrnai and .4ftcr Operation. AM. HEART .T. 24: 53.5, 1949. Pheochromoc~-t oma T+fore Rlwd Finnin ~~~l)crtll~-r~)i~lis~ll. Stewart, H. J., a’utl F ra II :, IV. I”. : ‘l’h~! PeriphPr:ll Hardy,
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