A
pulse is generated because of the pressure waves caused by the pumping action
of the heart.
It is
the indirect measure of heartbeat and activity of the heart. The normal
pulse has a small anacrotic wave on the upstroke which is not felt. This is
followed by a big tidal or percussion wave which is felt by the palpating
finger.
=> Rate
The rate
is measured as beats per minute and is calculated by counting the beats
for full one minute or counting for half a minute and then multiplying by two.
If the rhythm is irregular, the pulse should be counted for a full one minute.
The pulse rate can be used to check overall heart health and fitness level.
Generally lower is better, but bradycardias
can be dangerous. Symptoms of a dangerously slow heartbeat include weakness,
loss of energy and fainting.
Mostly,
the pulse rate and heart rate
are equal but in case of premature beats or atrial fibrillations, the heart
rate may be more than the pulse rate. The difference is called the pulse-rate
deficit. In adults, the normal pulse appears at regular intervals and has a
rate between 60-100 per min. There may be a mild variation in the rate between
the two phases of respiration which is called sinus arrhythmia.
newborn
(0–3 months old) |
infants
(3 – 6 months) |
infants
(6 – 12 months) |
children
(1 – 10 years) |
children over 10 years
& adults, including seniors |
well-trained
adult athletes |
99-149
|
89–119
|
79-119
|
69–129
|
59–99
|
39–59
|
=> Rhythm
The
normal rhythm is regular which indicates that the interval between
two beats is always equal. An irregular pulse may be due to sinus arrhythmia, ectopic beats, atrial fibrillation, paroxysmal atrial
tachycardia, atrial flutter, partial heart block etc. Intermittent dropping out
of beats at pulse is called "intermittent pulse". Examples of regular
intermittent (regularly irregular) pulse include pulsus bigeminus, second-degree
atrioventricular block.
An example of irregular intermittent (irregularly irregular) pulse is atrial fibrillation.
=> Force
Pulse
force is the force
or strength of the pulse felt when palpating. Also known as compressibility
of pulse, it is a rough measure of systolic blood
pressure. The
force provides an idea of how hard the heart has to work to pump blood out of
the heart and through the circulatory system.
The force is recorded using a scale
- 3+ Full, bounding
- 2+ Normal/strong
- 1+ Weak, diminished, thready
- 0 Absent/non-palpable
A 1+ force may reflect a decreased stroke volume [ can be
seen in heart failure, heat exhaustion, or hemorrhagic shock, etc]. A 3+ force
may reflect an increased stroke volume and is seen with exercise, stress, fluid
overload, and high blood pressure.
=> Tension
Tension corresponds to diastolic blood pressure. A low tension pulse (pulsus mollis), the vessel is
soft or impalpable between beats. In high tension pulse (pulsus durus), vessels
feel rigid even between pulse beats.
=> Volume
The degree
of expansion displayed by artery during diastolic and systolic state is
called volume. It is also known as amplitude, expansion or size of
pulse.
· Hypokinetic
pulse
A
weak pulse signifies narrow pulse pressure. It may be due to low cardiac output (as seen in shock, congestive cardiac
failure), hypovolemia,
valvular heart
disease (such as
aortic outflow tract
obstruction, mitral stenosis, aortic arch syndrome) etc.
· Hyperkinetic
pulse
A
bounding pulse signifies high pulse pressure. It may be due to low peripheral
resistance (as
seen in fever,
anemia,
thyrotoxicosis, hyperkinetic heart syndromede, A-V fistula, Paget's disease, beriberi,
liver cirrhosis), increased cardiac output,
increased stroke volume (as seen in anxiety, exercise, complete heart block, aortic regurgitation), decreased distensibility of
arterial system (as seen in atherosclerosis, hypertension
and coarctation of aorta).
The
strength of the pulse can also be reported:
- 0 =
Absent
- 1 =
Barely palpable
- 2 =
Easily palpable
- 3 =
Full
- 4 =
Aneurysmal or bounding pulse
=> Form
A form
or contour of a pulse is palpatiory estimation of arteriogram. A quickly rising and quickly
falling pulse (pulsus celer) is seen in aortic regurgitation. A slow rising and
slowly falling pulse (pulsus tardus) is seen in aortic stenosis.
=> Pulse Equality
Comparing
pulses and different places gives valuable clinical information.
A
discrepant or unequal pulse between left and right radial artery is observed in
anomalous or aberrant course of artery, coarctation of aorta, aortitis,
dissecting aneurysm, peripheral embolism etc. An unequal pulse between
upper and lower extremities is seen in coarctation to aorta, aortitis, block at
bifurcation of aorta, dissection of aorta, iatrogenic
trauma and arteriosclerotic obstruction.
=> Condition of Arterial Wall
A
normal artery is not palpable after flattening by digital
pressure. A thick radial artery which is palpable 7.5–10 cm up the forearm
is suggestive of arteriosclerosis.
Patterns
of Pulse
Several
pulse patterns can be of clinically significance. These include:
- Dicrotic pulse
Dicrotic
pulse is characterized
by two beats per cardiac cycle, one systolic and the other diastolic.
Physiologically, the dicrotic wave is the result of reflected waves from the
lower extremities and aorta. Conditions associated with low cardiac output and
high systemic vascular resistance can produce a dicrotic pulse.
- Pulsus Alternans
Pulsus
alternans is
characterized by a strong and weak beat occurring alternately, probably due to
alternate rather than regular contraction of the muscle fibers of the left
ventricle. Causes are left ventricular failure, toxic myocarditis, paroxysmal
tachycardias. It may occur for several beats following a premature beat.
It is
an ominous medical sign that indicates progressive systolic heart failure. To
trained fingertips, the examiner notes a pattern of a strong pulse followed by
a weak pulse over and over again. This pulse signals a flagging effort of the
heart to sustain itself in systole.
- Pulsus Bigeminus
Pulsus
bigeminus is the
coupling of the waves in a pair, followed by a pause. It is seen in alternate
premature beats, A.V. block, and sinoatrial block with ventricular escape. It
indicates a pair of hoofbeats within each heartbeat. Concurrent auscultation
of the heart may reveal a gallop rhythm of the native heartbeat.
- Pulsus Bisferiens
Pulsus
bisferiens is a
rapidly rising, twice beating pulse where both the waves are felt during
systole. It is characterized by two beats per cardiac cycle, both systolic,
unlike the dicrotic pulse. It's an unusual physical finding typically seen in
patients with aortic valve diseases if the aortic valve does not normally open
and close. Trained fingertips will observe two pulses to each heartbeat instead
of one.
- Pulsus Parvus ET Tardus
Pulsus
Parvus ET Tardus
is a slow rising pulse like the anacrotic pulse but the anacrotic wave is not
felt. It is seen in aortic stenosis. It is caused by a stiffened aortic valve
that makes it progressively harder to open, thus requiring increased generation
of blood pressure in the left ventricle.
- Pulsus Paradoxus
Systolic
blood pressure normally falls by 3-10 mm Hg during inspiration. This is because
though there is increased venous return to the right side of the heart, there
is relative pooling of the blood in the pulmonary vasculature as a result of
lung expansion and more negative intrathoracic pressure during inspiration.
This
decreases the venous return to the left atrium and ventricle and subsequently
causes a fall in left ventricular output thereby decreasing the arterial
pressure. When the drop is more than 10 mmHg, it is referred to as pulsus
paradoxus. During inspiration, the pulse is erroneously called pulsus
paradoxus although it is merely an exaggeration and not a reversal of the
normal.
The
paradox of this phenomenon is that in extreme cases the peripheral pulse can
disappear on inspiration while paradoxically, heart sounds remain audible
during the “missed beats”. A reverse pulsus paradoxus may occur in patients
receiving continuous airway pressure on a mechanical ventilator. Pulsus
paradoxus is seen in superior vena cava obstruction, lung conditions like
asthma, emphysema or airway obstruction, cardiac conditions like pericardial
effusion, constrictive pericarditis and severe congestive cardiac failure.
- Tachycardia
Tachycardia is an elevated resting heart
rate. In general an electrocardiogram (ECG) is required to identify the type of
tachycardia.
- Pulsatile
Pulsatile description of the pulse implies
the intrinsic physiology of systole and diastole.
Scientifically, systole and diastole are forces
that expand and contract the pulmonary and systemic circulations.
- Anacrotic
Anacrotic
pulse is a slow
rising, twice beating pulse where both the waves are felt during systole. The
waves that are felt are the anacrotic wave and the tidal wave. It is best felt
in the carotid artery in aortic stenosis.
- Thready Pulse
Thready
pulse rate is
rapid and the pulse wave is small and disappears quickly. This is seen in shock
especially cardiogenic.
- Waterhammer Pulse
Waterhammer
pulse is a large
bounding pulse associated with an increased stroke volume of the left ventricle
and a decrease in the peripheral resistance, leading to wide pulse pressure.
The pulse strikes the palpating finger with a rapid, forceful jerk and quickly
disappears. It is best felt in the radial artery with the patient’s arm
elevated. It is caused by the artery suddenly emptying because some of the
blood flows back from the aorta into the ventricle.
