average rate than men. The pulse of an infant ranges from 120 to 140 beats per minute.
Rates for children vary according to the size and the age of the child.
c. Activity affects the pulse rate. Exercise or heavy physical work cause the heart
to beat faster and the pulse rate to increase. Excitement, anger, and fear increase the
rate. Some drugs, such as caffeine, may also increase the pulse rate. If the patient has a
fever, the pulse rate increases in proportion to the body's temperature: the pulse rate goes
up about 10 beats for every 1F (0.56C). These conditions cause a temporary increase in
the heartbeat and pulse rate. The heartbeat and pulse rate that is consistently above
normal may be a sign of heart disease, heart failure, hemorrhage, an overactive thyroid
gland, or some other serious disturbance. The term for an abnormally rapid heartbeat is
tachycardia. When the heartbeat is continuously slow, below 60 per minute, the condition
is called bradycardia.
4-13. DESCRIBING THE PULSE
a. Pulse rate describes how often the heart beats.
b. Pulse volume describes the force with which the heart beats. The volume of
the pulse varies with the volume of blood in the arteries, the strength of the heart
contractions, and the elasticity of the blood vessels. A normal pulse can be felt with
moderate pressure of the finger. When every beat is easily felt, the pulse is described as
strong. When greater pressure exerted by the finger cannot blot out the pulse, it is called
full or bounding. A pulse with little force is described as weak or thready.
c. Pulse rhythm is the spacing of the heartbeats. When the intervals between
the beats are the same, the pulse is described as normal or regular. When the pulse
skips a beat occasionally, it is described as intermittent or irregular. A pulse may be
regular in rhythm but irregular in force, with every other beat being weak. To obtain an
accurate assessment of the heart rate, the pulse is counted by listening directly to the
heart (apical pulse).
4-14. FACTORS, WHICH AFFECT THE PULSE RATE
The pulse rate is an indicator of how fast the heart beats. The pulse rate is affected
by several factors.
a. Age. A normal pulse for infants range from 90 to 170 and the rate gradually
decreases up to age 14 when it is equal to the normal adult pulse rate of 60 to 100.
b. Body Build and Size. A short, fat person may have a higher rate than a tall,
slender person.
c. Blood Pressure. As the blood pressure decreases, the pulse will frequently
increase.
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