The arterial pulse is caused by the pressure wave that travels along the walls of the arteries when blood is ejected from the left ventricle into the aorta. As the aorta expands to accommodate the ejected blood volume, its elastic recoil causes the pressure wave. This pressure wave causes the expansion of the arterial wall, which can be felt as the arterial pulse. The velocity of the pressure wave is much faster than blood flow. Pulse pressure depends on factors like stroke volume, elasticity of arteries, and the character of blood ejection from the left ventricle. Examining the arterial pulse provides information about heart rate, rhythm, and can help diagnose diseases.
5. ARTERIAL PULSE
It is the pressure wave which travel
along the walls of Arteries when blood
is ejected from the left ventricle into the
aorta
6. Aorta expands to accommodate the ejected blood volume, when it
expands it has got elastic recoil, so it shortens back. This causes
pressure wave which leads to expansion of arterial wall which
can be palpated as arterial pulse.
Normally arterial pulse ends at arterioles.
So normally there is no capillary pulsations
8. The velocity of transmission of pressure wave
Is much higher than blood flow
When pressure pulse wave is transmitted to peripheral arteries, its
velocity increases.
The velocity of pressure pulse wave is much faster and independent of
the velocity of blood flow.
In the aorta, velocity of pressure pulse wave is 15 times greater than the
velocity of blood flow
In the peripheral arteries it is 100 times greater than the velocity of blood
flow.
9. Velocity of blood flow in large arteries=50 cm/sec
The rate of travel of pulse wave is about
4 meter/sec in aorta and its branches
8 meter/sec in large arteries
16 meter/sec in small arteries
11. The difference between systolic pressure and diastolic pressure
(120- 80 = 50 mmHg ) is called the pulse pressure.
It can be felt as a pulsation or throb in the arteries of the wrist or
neck with each heartbeat.
12. Pulse pressure depends
upon three factors
1. Stroke volume:
2. Elasticity of Arteries
3. Character of ejection of blood from the left
ventricle into aorta:
13. 1. Stroke volume:
Greater the stroke volume, greater will be the pulse pressure.
This stroke volume is also effected by
1. total peripheral resistance. When there is decreased total peripheral resistance,
i.e. arterioles are dilated so more blood will flow to the tissues. So
2. venous return increases. So this will in turn lead to increased stroke volume.
3. Mean systemic filling pressure also increases stroke volume.
14. 2. Elasticity of Arteries
Pulse pressure is inversely proportional to elasticity of arteries. Greater
the elasticity of arteries, less will be the pulse pressure.
As we pass from aorta to peripheral arteries elasticity decreases so the
pulse pressure increases as we pass away from aorta.
15. 3. Character of ejection of blood from the left ventricle into
aorta:
Sudden ejection results into greater pulse pressure as compared to
prolonged blood ejection.
16. Significance of arterial pulse
Part of routine clinical examination and from this we can
find out the heart rate and of course psychologically it is
very important.
There is also help in the diagnosis of different diseases.
When we palpate the arterial pulse we have to know the
following points:
Rate, rhythm, volume, character, condition of vessel wall.
17. WEAK OR THREADY PULSE: very low pulse pressure as
in blood loss or extreme of dampening as in circulatory shock.
PULSUS ALTERNANS: there is strong and weak pulse in
alternate beats. One beat is strong and other is weak. Feature of LVF.
18. PULSUS PARADOXUS
Pulse becomes weak during inspiration and becomes
strong during expiration. Occurs physiologically. Less
blood returns to the atrium during inspiration.
Becomes very prominent in pericardial effusion and
constrictive pericarditis
19. COLLAPSING OR WATER
HAMMER PULSE
seen in aortic incompetence. There is rapid rise in
pressure during systole and then it collapses rapidly.
PLATEAU PULSE: seen in aortic stenosis. Slow rise
in pressure
20. REGULARLY IRREGULAR: ATRIAL FLUTTER.
IRREGULARALY IRREGULAR: Atrial fibrillation
STRONGER PULSE: During fever, exercise, pregnancy,
hyperthyroidism, anxiety, excitement. Old age because of increased
pulse pressure.