Altitude
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Disturbances Of The Heart
It has long been known that altitude increases the heart rate and
tends to lower the systolic and diastolic blood pressures; that
these conditions, though actively present at first, gradually return
to normal, and that after a prolonged stay at the altitude may
become nearly normal for the individual. Burker [Footnote: Burker,
K.; Jooss, E.; Moll, E., and Neumann, E.: Ztschr. f. Biol., 1913,
lxi, 379. The Influence of
ltitude on the Blood, editorial, THE
JOURNAL A. M. A., Nov. 1, 1913, p. 1634.] showed that altitude
increases the red blood cells from 4 to 11.5 percent, and the
hemoglobin from 7 to 10 percent The greatest increase in these
readings is in the first few days. It has also been shown that with
every 100 mm. of fall of atmospheric pressure there is an increased
hemoglobin percentage of 10 percent over that at the sea level.
[Footnote: Blood and Respiration at Moderate Altitudes, editorial,
THE JOURNAL A. M. A., Feb. 20, 1915, p. 670.]
Schneider and Havens [Footnote: Schneider and Havens: Am. Jour.
Physiol., March, 1915.] find that in low altitudes abdominal massage
increases the red corpuscles, and the percentage of hemoglobin in
the peripheral vessels. While there is thus apparently a reserve of
red corpuscles while the individual is in a low altitude, in a high
altitude they find such reserve to be absent; in other words,
abdominal massage did not cause this increase in red corpuscles in
the peripheral vessels. This absence of reserve is easily accounted
for by the fact that after one reaches the high altitude there is an
increase in red corpuscles and hemoblogin in the peripheral blood.
Schneider and Hedblom [Footnote: Schneider and Hedblom: Am. Jour.,
Physiol., November, 1908.] showed that the fall in systolic pressure
at altitudes is greater and more certain than the fall in diastolic,
some individuals even having a rise in diastolic pressure. This rise
in diastolic pressure is probably caused by dyspnea.
Schrumpf, [Footnote: Schrumpf: Deutsch. Arch. f. klin. Med., 1914,
cxiii, 466] on the other hand, finds that normal blood pressure is
not much affected by an ascent of about 6,500 feet, while patients
with arteriosclerosis and hypertension, without kidney disease, have
a fall in pressure. A patient with coronary disease should certainly
not go to any great altitude, while patients with compensated
valvular lesions, he found, were not injured by ordinary heights. He
found that altitude seemed to decrease high systolic and diastolic
pressures, while it even elevated those which were below normal, and
caused these patients to feel better.
Any person who has a circulatory disturbance, and who must or does
go to a higher altitude, should rest for a series of days, until his
blood pressure and blood have reached an equilibrium.
Smith [Footnote: Smith, F. C.: The Effect of Altitude on Blood
Pressure, THE JOURNAL A. M. A., May 29, 1915, p. 1812.] made a
series of observations on blood pressures at Fort Stanton which has
an altitude of 6,230 feet. He took the blood pressure readings in
fifty-four young adults, seventeen of whom were women, and found
that the average systolic reading in the men was 129 mm., and in the
women 121, while the average diastolic in the men was 84, and in the
women 82. Therefore he agrees with Schrumpf that the effect of
altitude on normal blood pressure has been overestimated. In
tuberculosis he found that the effect of altitude was not great. He
does not believe that this amount of altitude, namely, a little more
than 6,000 feet, makes much difference in an ordinary tuberculous
patient. He did not find that artificial pneumothorax made any
important change in the blood pressure. His findings do not quite
agree with Peters and Bullock, [Footnote: Peters, L. S.r and
Bullock, E. S.: Blood Pressure Studies in Tuberculosis at a High
Altitude, Arch. Int. Med., October, 1913, p. 456.] who studied 600
cases of tuberculosis at an altitude of 6,000 feet, and found the
blood pressure was increased, both in normal and in consumptive
individuals. They also found that the increase in blood pressure,
which kept gradually rising up to a certain limit, was indicative
that the tuberculous patient was not much toxic; therefore the
increase in blood pressure was of good prognosis.