Practicals
OBJECTIVES
After completion of the practical student should:
- Know the procedure and importance of arterial pulse examination
- Know the parameters to be examined for examination of pulse
- Know about various waves of arterial pulse
- Be able to describe various abnormal pulses
- Be able to enumerate causes of tachycardia and bradycardia
- Be able to enumerate conditions where abnormal rhythm, volume, character of pulse is present
- Be able to enumerate peripheral sites for pulse examination.
INTRODUCTION
Pulse examination is one of the vital signs that must be checked with general examination. Arterial pulse is defined as the rhythmic expansion of the arterial wall due to transmission of pressure wave produced during each systole of heart along the walls of the arteries.
PRINCIPLE
Each ventricular contraction generates a pressure wave which is transmitted along the vessel walls, this pressure wave expands the arterial wall and the expansion is palpated as pulse.
METHOD OF EXAMINATION
Arterial pulse is examined by observing its following aspects/parameters of pulse:
- Rate
- Rhythm
- Volume (Amplitude)
- Synchronicity/similarity on both sides
- Character
- Condition of the vessel wall
- Radiofemoral delay
- Presence of other peripheral arterial pulses.
Usually radial artery is palpated for arterial pulse examination because it is easily accessible and it lies over the hard surface (lower end of head of radius bone).
PROCEDURE
- Let the subject sit comfortably and let him relax for some time.
- Semi-pronate his forearm and flex his wrist.
- Put middle three fingers (index, middle and ring finger) of your (examiner's) right hand on the subject's radial artery.
- Keep your examining index finger towards the subject's heart. The pressure of the index finger over the subject's radial artery is varied to judge the force and tension of the pulse and to obliterate the flow of blood into the radial artery during examination of condition of vessel wall.
- The middle finger is used to feel the pulse wave.
- The ring finger is kept towards the subjects thumb. It is used to apply pressure to prevent retrograde pulsation from the palmar arch.
- Compress the subject's radial artery against the head of his radius bone.
- Now study various aspects/parameters of arterial pulse as described below:
- Rate: For rate use your three fingers, count the number of pulse waves for one minute.
- Rhythm: Study the spacing between successive pulse waves. Note whether it is constant or not. When spacing between all the waves is constant, the pulse is said to be “regular.” When spacing is not constant, pulse is said to be irregular.
- Volume: Feel the uplift given to the palpating fingers during each pulse wave, i.e. the degree of expansion of the arterial walls during each pulse wave. It will tell you the volume of the pulse.
- Synchronicity: Simultaneously palpate radial arteries on both arms and look for the synchronicity of pulse on both the sides.
- Character: Study the rise, maintenance and fall of the pulse wave. If no abnormality is detected, the character of a pulse is described as normal.
- Condition of vessel wall: Try to palpate the vessel wall using your three fingers:
- With the index finger obliterate the flow of blood into the radial artery
- With the ring finger empty the vessel
- With middle finger roll the artery against the bone to assess the thickness of the arterial wall.
- Normally, the arterial wall is not palpable.
- Radiofemoral delay: Keep three fingers of your left hand over subject's radial artery and the three fingers of your other hand on the femoral artery of the subject. Compare the appearance of femoral pulse with appearance of radical pulse. The two pulses should appear together. Mark if any delay is present between them.
- Other peripheral pulses: Examine other peripheral pulses according to Table 1.1 and Figures 1.1 to 1.7.
PRECAUTIONS
- Subject should be examined in a warm room. Cool environment may cause peripheral vasoconstriction and reduce the peripheral blood flow.
- Arrangements should be made so that the subject's pulses can easily be examined from both sides of the bed.
- Begin the pulse examination once the subject's nervousness has subsided. Slight amount of exertion or nervousness is likely to quicken the pulse so it is important to put your subject at ease and examine the pulse a little after he arrives so as to overcome these factors.
- Subject's forearm should be semi-pronated and wrist flexed.
- Palpation should be done using the fingertips (as the tips are very sensitive).
- Avoid palpation with the thumb. Examination with thumb carries a greater likelihood of confusion with the examiner's own pulse and generally has less discriminating sensation than the fingers.
- For assessing character in carotid artery and brachial artery particularly, thumb may be used because kinesthetic sensitivity is better in the thumb to detect pulse character.
- Pulse rate should be counted for minimum of one minute. If irregularity is detected, the pulse is counted for three minutes and the average of the three may be taken.
- If pulse is irregularly irregular, heartbeats must be auscultated simultaneously to detect pulse deficit if present.
- Pulses of both sides should be examined and compared.
OBSERVATIONS
Observe the rate, rhythm, volume, synchronicity, character of pulse, condition of vessel wall, radiofemoral delay and confirm the presence of all other peripheral pulses.
RESULT
It is very important to give result stating all the parameters of pulse. Students commonly make this mistake; they just express the pulse rate and leave all other parameters. One should give result of pulse examination describing rate, rhythm, volume, synchronicity, character, vessel wall condition, radiofemoral delay and the presence or absence of other peripheral pulses, e.g. if pulse has all the normal parameters the result will be ‘x’ beats/ minute, regular, good volume, synchronous on both sides, vessel wall is not palpable, there is no abnormality in character and no radiofemoral delay is present. All the peripheral pulses are palpable.
DISCUSSION
Significance of Pulse Examination
Much valuable information can be gained from examination of the peripheral pulses in addition to the status of the arterial system itself. Variations in the rate, rhythmicity, intensity, and contour of the pulse wave may yield insight into a variety of disease states. The rapid, thready pulse of hypovolemic shock is a well-known clinical sign, as is the rapid, snapping pulse characteristic of thyrotoxicosis, and the collapsing, “water-hammer” pulse of aortic insufficiency. Different aspects of pulse examination provide clue to various physiological and pathological conditions.
Rate
In adults a normal pulse rate after a period of rest is between 60 to 80 beats per minute.
- Tachycardia is defined as a pulse rate more than 100 per minute.
- Bradycardia is defined as a pulse rate less than 60 per minute.
- Rate between 60 and 100 beats/min must be seen as normal.
Physiological Conditions where Higher Pulse Rate/Heart Rate is Present
- Infancy: In newly born infant, pulse rate is about 130/min
- Childhood: In children PR is higher than adults, it comes to adult level at around 20 years of age
- In females pulse rate is slightly higher (5/min as compared to males).
- After exercise
- After eating
- During emotions like anger, excitement
- In pregnancy
- In high temperature
- During deep inspiration
- In healthy young individuals breathing at normal rate, the heart rate varies with the phase of respiration: it accelerates during inspiration and decelerates during expiration, especially if the depth of respiration is increased. This phenomenon of quickening of pulse during deep inspiration and slowing during deep expiration is called sinus arrhythmia. It is a normal phenomenon and is due to fluctuations in parasympathetic output to heart. 9During inspiration, impulses in the vagi from the stretch receptors n the lungs inhibit the cardioinhibitory area in the medulla oblongata. The tonic vagal discharge that keeps the heart rate low (vagal tone) decreases and heart rate increases. This can be quite marked in children and adolescents but is uncommon over the age of 30. It can persist a little longer in the physically fit.
Pathological conditions where higher pulse rate is present are:
- Fever: In fever PR is more because of increased sympathetic activity.
- Anemia: Tachycardia occurs as a compensatory mechanism to improve oxygen supply to tissues.
- Thyrotoxicosis: Thyroxin increases the number of β receptors in heart and also increases sensitivity of these receptors to catecholamines.
- Paroxysmal atrial tachycardia.
- Atrial flutter and fibrillation.
- Circulatory shock.
Physiological conditions where lower pulse rate/ heart rate is present:
- Old age
- During deep expiration
- In athletes; because of their increased vagal tone
- In emotions like grief
- During sleep and meditation.
Pathological conditions where lower pulse rate/heart rate is present
- Myxedema: Decreased PR is present because decrease in thyroxin levels will decrease the number of β receptors and their sensitivity to catecholamines.
- Brain tumors: Decreased PR is present because the increased intracranial pressure will lead to Cushing's reflex.
- Heart block: Decrease in pulse rate depends on degree of heart block. In complete heart block, rate may be 30 to 40/minute.
- Some drugs decrease heart rate, e.g.
- Propanolol: It decrease heart rate by inhibiting b receptors of SA node.
- Digitalis: It stimulates vagal nuclei in medulla; increase in vagal activity will decrease heart rate.
- Obstructive jaundice.
Pulse Deficit
In conditions of irregular rhythm, some of the heart beats may be weak and not sufficient enough to generate pressure waves in the walls of the arteries. So, radial pulse may not reflect true ventricular contraction. In such conditions, the heart rate (counted by auscultating the apex) will be more than pulse rate. Difference between pulse rate and heart rate is called pulse deficit. It is usually seen in atrial fibrillations and heart block (where deficit is more than 10).
Rhythm
It is the spacing order at which successive pulse waves are felt. When spacing between all the waves is constant, the pulse is said to be regular. When spacing is not constant, pulse is said to be irregular. The irregular pulse may have a fixed pattern of irregularity, i.e. irregular at regular interval then it is said to be regularly irregular pulse. When irregularity has no pattern then it is said to be irregularly irregular pulse.
Causes of Irregular Rhythm of Pulse
- Premature contraction or extrasystole/ectopic beat. It is due to generation of impulse from an ectopic focus present in ventricle.
- Atrial fibrillations. Irregularly irregular pulse is present.
- Atrial flutter with irregular block. Irregularity occurs due to block in conduction that occurs irregularly.
- Heart block with dropped beat.
Volume
It is the degree of expansion of the arterial wall during each pulse wave. It is felt as an uplift given to the palpating fingers. It is difficult to describe but can be appreciated by palpating the artery. Pulse volume should be compared bilaterally. It can be normal, high or low. It gives an indication of the stroke volume of the left ventricle.
Low Volume Pulse
It is also called pulsus parvus. It occurs when the stroke volume of heart decreases. Pulsus parvus/low volume pulse is present in:
- Shock
- Aortic stenosis
- Obstructive cardiomyopathy
- Pericardial effusion
- Pulmonary stenosis.
High Volume Pulse
It is also called pulsus magnus. It occurs due to increase in the stroke volume of heart or widening of pulse pressure. It is present in:
- Anemia
- Fever
- Old age
- Exercise
- Patent ductus arteriosus
- Thyrotoxicosis
- Aortic incompetence.
Character
For examination of pulse character, carotid or brachial artery is more suitable. The character is described as normal when no abnormality is detected in the rate of rise and fall of waveform of the pulse. Character of a pulse is better understood when the pulse is recorded on a paper with the help of transducer and a recorder.
Waves of Pulse
Normal radial pulse when recorded has following waves (Fig. 1.8).
The ‘p’ wave: It is called percussion/tidal wave occurs due to ejection of blood from ventricles during systole.
The ‘n’ notch: It is present in the descending limb of pulse tracing and represents the closure of aortic valve.
The ‘d’ wave: It is called dicrotic wave. It occurs due to rebound of blood against the closed aortic valve during diastole.
The ‘a’ wave: It is called anacrotic wave. It is sometimes seen in the upstroke of the pulse wave. It occurs due to change in velocity of ejection of blood from ventricle towards late systole.
Depending on any change in the normal wave forms; various types of abnormal pulses are described. Different types of abnormal pulses are:
Anacrotic pulse/slow rising pulse
It has two upstrokes. A secondary wave occurs in the upstroke of the pulse. The pulse wave is slow to rise and occurs when the ventricular ejection is prolonged (Fig. 1.9). Usually it is seen in aortic stenosis.
Dicrotic Pulse/Twice beating pulse
A dicrotic pulse results from the accentuated diastolic dicrotic wave that follows the dicrotic notch. It is called ‘Twice beating pulse because the dicrotic wave is prominent and gives impression of 2 beats (Fig. 1.10). It is present in fever.
Water Hammer Pulse/Collapsing or Corrigan's Pulse
The Corrigan or water-hammer pulse is characterized by an abrupt, very rapid upstroke of the peripheral pulse (percussion wave), followed by rapid collapse. Dicrotic notch is usually absent. It is best appreciated by raising the arm abruptly and feeling for the characteristics in the radial pulse (Fig. 1.11). It probably results from very rapid ejection of a large left ventricular stroke volume into a low resistance arterial system.
It occurs most commonly in:
- Chronic aortic regurgitation.
- Patent ductus arteriosus.
- Large arteriovenous fistulas.
- Hyperkinetic states like thyrotoxicosis and anaemia.
- Extreme bradycardia.
Pulsus alternans
Pulsus alternans is a variation in pulse amplitude occurring with alternate beats due to changing systolic pressure. Pulse is regular but alternate beats are strong and weak. It is best appreciated by applying light pressure on the peripheral arterial pulse, and can be confirmed by measuring the blood pressure (Fig. 1.12). When the cuff pressure is slowly released, phase I Korotkoff sounds are initially heard only during the alternate strong beats; with further release of cuff pressure, the softer sounds of the weak beat also appear. Pulsus alternans should not be diagnosed when the cardiac rhythm is irregular. It is present in:
- Left ventricular failure (It is the most important cause of Pulsus alternans).
- Hypertrophic cardiomyopathy.
Pulsus Bisferiens
It is a combination of the low raising pulse (anacrotic) and the collapsing pulse. This is typically seen in aortic stenosis associated with aortic incompetence (Fig. 1.13).
Pulsus Paradoxus
There is an accentuation of normal phenomenon of decrease in pulse volume with inspiration. There is nothing paradoxical about the pulse character unlike what the name suggests. Normally the 14decrease in amplitude of pulse with inspiration does not exceed 8 to 12 mm Hg. This much decrease in pressure can't be appreciated on palpation. When there is a more marked inspiratory decrease in arterial pressure exceeding 20 mm Hg, the pulse is termed Pulsus paradoxus (Fig. 1.14). In contrast to the normal situation; this can be easily detected on palpation. It is present in:
- Constrictive pericarditis
- Pericardial effusion
- Chronic obstructive pulmonary disease
- Massive pleural effusion.
CONDITION OF THE VESSEL WALL
Normally in young adults, arterial wall is soft, elastic and impalpable. But in old age atherosclerosis thickens the arterial wall and it may become palpable. In such conditions, the radial, brachial and temporal arteries may be quiet prominent and tortuous.
RADIOFEMORAL DELAY
In normal adults, the upstrokes of the radial and femoral pulses normally appear simultaneously. Normally there is no radiofemoral delay. A delay in the onset of the femoral pulse, generally associated with diminished amplitude, suggests coarctation of the aorta especially when constriction is present distal to the origin of the left subclavian artery.
OTHER PERIPHERAL PULSES
In absence of any pathology, all peripheral pulses are well felt and appear simultaneously on both sides. Peripheral pulses may not be felt properly in peripheral vascular disease. Reduced or absent arterial pulses are a sign of impaired blood flow. Palpation of peripheral pulses is important in diagnosis of various diseases like:
- Congenital abnormalities (coarctation of the aorta, anomalous peripheral arteries)
- Intrinsic arterial disease (atherosclerosis, thrombosis, arteritis)
- Vasospastic disorders (Raynaud's phenomenon)
- Involvement of the vessel by extrinsic compression (thoracic outlet syndrome, trauma, neoplasms).
WORK SPACE
Name of subject
Age
Sex
Observations
Rate:
Rhythm
Volume
Synchronicity
Character
Condition of Vessel Wall
Radio femoral delay
Presence of other peripheral Pulses
Result
ANSWER THESE QUESTIONS
Q1. Define arterial pulse.
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Q2. What should be the position of subject's arm for pulse examination?
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Q3. Why three fingers are used in pulse examination?
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Q4. Draw a labeled diagram of pulse wave.
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VIVA QUESTIONS
Q1. What are the precautions taken for pulse examination?
Q2. What is the significance of arterial pulse examination?
Q3. Why some time is given to the patient/subject before beginning pulse examination?
Q4. What is normal pulse rate?
Q5. What is pulse deficit? In which condition pulse deficit is present?
Q6. What is sinus arrhythmia?
Q7. What is tachycardia? What are the conditions in which it is seen?
Q8. What is bradycardia? What are the conditions in which it is seen?
Q9. Why pulse rate is low in athletes?
Q10. How will you examine pulse volume?
Q11. What are the conditions where pulse has low volume?
Q12. What are the conditions where pulse has high volume?
Q13. What is anacrotic pulse?
Q14. What is dicrotic?
Q15. What is water hammer pulse/collapsing pulse?
Q16. What is pulsus paradoxus?
Q17. What is pulsus alternans?
Q18. What is radiofemoral delay? How it is examined? What is its significance?
Q19. What is the significance of examining peripheral pulses?