Vital signs: pulse types and factors affecting pulse rate

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Part Two of Vitals:

Pulse – wave of blood created by contractions of the LEFT ventricle of the heart

How does the pulse occur: blood enters the arteries with each contraction, causig these pulses

Pulse rate: the number of pulse sensations per minute

The pulse is also called the heart rate

Peripheral and apical pulse are the two kinds of pulse

Peripheral: located in the periphery of the body

Foot and hand: examples of where to find peripheral pulses in the body

Apical pulse: located at the apex of the heart

Is also called the PMO or the point of maximal impulse

The apical pulse is found at the point of maximal impuse which is located at the fifth intercostal space, midclavicular line

- often listen to this pulse with a stethoscope as it is the direct pulsation of the heart

The 9 major factors that affect pulse rate are: meds, gender, age, exercise, fever, hypervolemia, stress, position changes, pathology

1. Gender – men’s pulse rate is slightly lower than the average

2. Age – as people age, pulse rate gradually decreases – changes in heart muscles

3. Exercise – increases with activity

4. Medications – drugs affect pulse rate such as cardio tonic, beta blockers decrease it. Caffeine, nicotine and epinephrine increase it.

5. Fever – heart rate increases, lowered BP b/c of peripheral vasodilation

6. Hypervolemia - small amount of blood loss results in temp adjustment in HR.

7. Stress – sympathetic nervous stimulation increases heart activity

8. Position Changes – sitting and standing blood pools in dependant vessels of venous system results in blood return to heart and reduces BP and HR.

9. Pathology – heart conditions or those that impair oxygenation alter HR

Adult body has 5 litres of blood, can usually lose up to ten percent without adverse effects.

When assessing pulse, assess : rate, rhythm, strength and equality

1. Rate – normal is 60-100 bpm

Determined at beginning of every shift so the nurse will have baseline assessment

Sound heard with stethoscope is lub dub (S1 and S2 sounds) = one beat

Tachycardia: above 100 beats

Bradycardia: below 60 bpm

· if there is a difference between apical heart rate and the peripheral heart rate, there may be inefficient contraction of the heart muscle

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- Bradycardia – rate is about 54 bpm

- Could be athlete, result of meds

- May be symptomatic – won’t feel well, have weakness, tiredness, dizziness

- Asymptomatic – accustomed to heart rate and can function

Tachycardia – 110 bpm

- can be caused by certain meds, excitement, dehydration, shock

- not always a bad thing, natural response to fever, exercise or activity

- goal is to understand reasons

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Rhythm – pattern of the beats and intervals between beats

- should be equal

Dysrhythmia or Arrhythmia – irregular pulse , consists of irregular beats or a predictable pattern of irregular beats

- apical pulse should be assessed and an ECG may be necessary to define this

- holter monitor to determine HR related to activity

- telemetry – portable pack

Sinus Dysrhythmia – normal slowing and speeding of the heart rhythm as it relates to respiration – children

Pulse Strength – volume or amplitude of blood

Should be the same for each beat and can range from absent to bounding

A normal pulse is felt with mod pressure of fingers and obliterated with greater pressure

Visible to the naked eye – bounding pulse

§ Weak, feeble or thready = easy to obliterate

§ Full or bounding = difficult to obliterate

Equality – pulses being the same on both sides of the body

If bilateral pulses differ it means disease states or aberrant blood vessels

Aberrant – means abnormal

Bilaterally equal – when right and left pulses are the same

What should you never do with the carotid artery – assess the pulses at the same time as it may cause occlusion to the cerebral blood flow, - passing out

1. Temporal – where the temporal artery passes over the temporal bone of the head.

2. Carotid – side of the neck where carotid artery runs between the trachea and sternocleidomastoid muscle.

3. Apical – at the apex of the heart. Adult – left side of the chest no more than 8 cm to the left of the sternum at 4th, 5th or 6th intercostal space. In older adult, may be further left (ie enlarged heart). Before age 4 the apex is left of the midclavicular line (MCL); from 4-6 years it is at MCL; 7-9 years apical pulse is at 4th or 5th intercostal space. In men – just below nipple; in women, just under left breast. Listen for the sound Lub dub, which is counted as one beat.

4. Brachial - at the brachial artery found at the inner aspect of the bicep muscle of the arm (especially in infants) or medially in the antecubital space (the depression in front of the elbow).

5. Radial – where radial artery runs along the radial bone, on the thumb side of the inner aspect of the wrist.

6. Femoral – located in the groin area where the femoral artery passes alongside the inguinal ligament.

7. Popliteal – where the popliteal artery passes behind the knee. May be difficult to locate, but it can be palpated if the client flexes the knee slightly.

8. Posterior tibial - on the medial surface of the ankle where the posterior tibial artery passes behind the medial malleolus.

9. Pedal - where the dorsalis pedis artery passes over the bones of the foot. Can be palpated by feeling the dorsum (upper surface) of the foot on an imaginary line drawn from the space between the big and 2nd toe to the middle of the ankle.

How to assess the pulse – palpation using three middle fingertips to apply moderate pressure

Why do we use the pads of the fingers? – the pads are the most distal part of the finger and are the most sensitive areas

How do we assess an apical pulse: locate the angle of Louis between the manubrium, top of sternum and body of sternum

Angle of Louis – palpitated just below suprasternal notch and feels prominent, slide a giner to just the left of the sternum and palpates the second intercostal space

Count down each space until the 5 one is felt, move finger along till midclavicular line, the apical impuse is just medial to this.

The carotid pulse is often used in critical care situations as it is easily accessible and traditionally has a very strong pulsation that is easy to locate. Find the middle of the trachea (throat) and move the index and middle finger down into the notch or indentation in the side of the neck, making sure not to press too hard. Always work from the side closest to you and never assess the carotid artery’s simultaneously as this will occlude the blood flow to the brain, causing the patient to pass out.

The carotid pulse is the recommended site when a client’s condition suddenly worsens. The heart will continue to deliver blood to the brain via the carotid arteries as long as possible. When cardiac output declines significantly, peripheral pulses weaken and are difficult to palpate, so the carotid pulse is often the only available pulse that can be used.

How to take a pulse for a infant: place baby in supine position which will increase HR, locate apical pulse – 4th intercostal space, lateral to the midcalvicular line

How to take a child’s pulse: when taking a peripheral, have parents close by

- apical – have child in supine or sitting

- demonstrate with stuffy or have child hold it

Where is the apex of heart located in young children – 4th intercostal space

Where is the apex of heart located in children 7 years are older – 5th intercostal space

What pulse is the most accurate for adults – apical

Why is the apical pulse more accurate in adults – cardic changes can cause decrease in cardiac output, sclerotic changes to heart valves, dysrhythmias

What to check in the elderly – pedal pulses as they have bad peripheral circulation

What is blood pressure: force of the blood pushing against artery walls

Systolic pressure – pressure of blood exerted on the artery wall as result of contraction of the left ventricle

Diastolic pressure- when ventricles are at rest

Blood pressure is measured in: mm Hg

What is the top number of blood pressure; systolic

Bottom number of blood pressure: diastolic

When is the blood pressure the lowest – when you sleep

Blood pressure measurements are taken using a sphygmomanometer.

The 10 factors that influence blood pressure is age, exercise, stress, race, obesity, sex gender, meds, sodium intake, diurnal variaitons, medical condtions

1. age – rises with age, high in elderly people due to reduced elasticity of arteries, rigid artery walls cause increased systolic pressure

2. exercise – increases cardiac output and BP

3. stress – SNS increases cardiac output and vasoconstriction of the arteriole, severe pain can decrease it and cause shock

4. race – black males over 35 have higher BP

5. obesity – have higher bp and predisposes hypertension

6. Sex/gender – females have lower BP than males, increases after menopause

7. Medications – caffeine increase BP, diuretics decrease BP

8. Sodium intake – high sodium intake can increase the release of natriuretic

hormone which indirectly contribute to high BP, stimulates vasoconstriction

9. Diurnal variation – BP is lowest in morning and peaks in late afternoon

10. Medical conditions – this will change if there are conditons that affect cardiac output, blood volume, blood viscosity, compliance of arteries

11. Smoking and Tobacco use – affects arteries and blood viscosity, causes vasoconstriction

12. Alcohol – people who drink over 2 day= 1.5 increase in frequency of hypertension

What provides a temp rise of blood pressure of 5 -10 mm Hg

Why do steady smokers sometimes have a lower blood pressure than non-smokers? Nicotine causes decreased appetite – weightless, lowers blood pressure

White coat effect – increased in BP caused by stress of going to health care provider

How much sodium should you have if you have high BP? 1495-2300

How much salt should you have daily? 1200mg-1500mg

Hypertension – blood pressure above normal

Example of hypertension blood pressure count: 140/90

What kind of blood pressure needs reassessment? Hypertension

What is hypertension a major risk factor for: heart attack, heart failure, peripheral vascular disease and blindess

What is hypertension caused by – loss of elasticity in arteries

What kinds of factors that contribute to hypertension smoking, obesity, alcohol, caffeine, immobility, high cholesterol, stress

Primary hypertension – increase BP of unknown cause

Secondary Hypertension – increased BP of a known cause

What causes Secondary Hypertension: renal failure, tumours of the adrenal medulla, diabetes

Hypotension – below normal bp,

What is the systolic pressure for hypotension 85-110

What makes hypotension life threatening: pallor, skin mottling, clamminess, confusion, increased HR, decreased urinary output

What can cause hypotension: opioids, bleeding, severe burns, prolonged diarrhea, vomiting

What is the opioid that contributes to hypotension: morphine

What must be done as a nurse with a client of hypotension: monitor between ambulation and transfer to prevent falls, moniter meds

Orthostatic Hypotension – blood pressure that falls when client sits or stands

What is results in O hypotension – peripheral vasodilation

What is peripheral vasodilation – body leaves the central organs like the brain into the periphery, makes people feel faint

How to ambulate a person with Orthostatic Hypotension: supine postion, dangle feet by bed before rising, assist to stand slowly, after 1-3 min in upright position, recheck BP and p

What BP and P dictates orthostatic hypotension : 20 bpm, decrease of 10mm Hg

When assessing blood pressure there are two common sites used: The arm (brachial artery) and the leg (popliteal artery). The leg is generally used if a BP cannot be measured on either arm because of disease or trauma. The BP in one thigh should be compared with the BP in the other thigh. Never measure a BP in an arm or thigh that has a shoulder, arm, hand, hip, knee, or ankle injury or disease. Other considerations would be to make sure the limb does not have a cast or bulky bandage on it. Never take a BP on a side of the body where the client has had removal of axilla or inguinal lymph nodes. Likewise, stay away from measuring a BP in a limb with an intravenous or arteriovenous fistula (for renal dialysis).

Direct measurement involves invasive monitoring, meaning the insertion of a catheter into the brachial, radial or femoral artery. In direct measurement, the arterial pressure is represented as wavelike forms displayed on an oscilloscope. With correct placement, this BP reading is highly accurate.

Indirect measurement involves non-invasive monitoring, using a sphygmomanometer, cuff, and stethoscope. Indirect monitoring is the most common used in health care facilities. The two methods of indirect BP monitoring are the auscultatory and palpatory methods. The auscultatory method uses a stethoscope to hear the pulsation sounds called Korotkoff’s sounds. The palpatory method is used when Korotkoff’s sounds cannot be heard and electronic equipment to amplify the sounds is not available or when an auscultatory gap occurs (see below). Instead of listening for the blood flow sounds, the nurse palpates the pulsations of the artery as the pressure in the cuff is released. To palpate the diastolic BP the nurse applies light to moderate pressure over the pulse point. Systolic BP is read from the sphygmomanometer when the first palpation is felt. A single whip-like vibration, felt in addition to the pulsation, identifies the point at which the pressure in the cuff nears the diastolic BP. This vibration is no longer felt when the cuff pressure is below the diastolic BP.

How to apply BP cuff

Applying the blood pressure cuff. In the adult, the bladder should encircle 80% of arm. The patient is in the sitting position with feet on the floor and the forearm at heart level (sitting or lying).

The nurse locates the brachial artery pulsation. Pump the cuff up to the point when a pulse is no longer felt (this is the point when the blood flow in the artery is stopped). Pressure is released slowly at 2 mm Hg per heart beat, while the nurse observes the readings on the manometer and relates them to the pulsations. Palpating the systolic pressure where blood flow has stopped, provides a baseline for taking an accurate BP.

Tighten the screw valve so that it is easily released using the thumb and index finger on one hand. The other hand positions the stethoscope.

Place the stethoscope over the pulsations felt in the brachial artery.

Pump the cuff to 30 mmHg above the palpatory systolic pressure. Release the bulb pressure slowly at about 2 mm Hg per heart beat.

Korotkoffs Sounds

Phase 1 – the pressure level at which the first faint, clear tapping or thumping sounds are heard. These sounds gradually become more intense. To ensure that they are not extraneous (outside) sounds, the nurse should identify at least two consecutive taping sounds. The first tapping sound heard during deflation of the cuff is called the systolic BP (SBP).

Phase 2 – the period during deflation when the sounds have a muffled, swooshing or swishing quality.

Phase 3 – the period during which the blood flows freely through an increasingly open artery and the sounds become crisper and more intense and again assume a thumping quality but softer than in phase 1.

Phase 4 – the time when the sounds become muffled and have a soft, blowing quality.

Phase 5 - the pressure level when the last sound is heard. This is followed by a period of silence. The pressure at which the last sound is heard is known as the diastolic BP (DBP) in adults.

Normal BP Readings

Adults > 18 years

< 120/80

14-17 years

120/75

10-13 years

110/65

6 years

105/65

1 years

95/65

1 month

85/54

newborn

40 mean

The nurse should use lifespan considerations to help determine normal blood pressure readings.

How to get infant BP – pediatric stethoscope with small diaphragm

Arm and thigh pressures are equivalent in children less than a year in age

What is a quick way to determal SBP of child SBP =80+(2 times age)

When should BP be taken in kids – more than three and anytime with medical conditions

What should the cuff length and arm circumference be for kids - 40%

What is common in thigh pressure rather than in arm – 10mm higher in thigh than arm

What is the DBP considered to be in kids: onset of phase 5 in sounds – muffled

When taking BP in adults, what should a nurse look out for; skin fragility, antihypertensive meds

What should nurses look out for with elderly meds and BP – meds – vasodilation, loss of baroreceptor efficiency

What position should the BP be taken in elderly patients: lying, sitting and standing