Blood Pressure

Blood pressure (BP) is the measurement of the pressure that the blood exerts on:

the walls of the arteries during various stages of heart activity.

Systolic

first pump; pressure occurs in the walls of the arteries when the left ventricle of the heart is contracting and pushing blood into the arteries.

Diastolic

Constant pressure in walls of arteries when the left ventricle of the heart is at rest

How is systolic and diastolic documented, and what is considered a normal BP?

• systolic/diastolic

• normal: <120 systolic and <80 diastolic (120/80 and below)

Define pulse pressure

the difference b/w systolic and diastolic (s - d = p)

What does pulse pressure tell us?

about the health of the arterial walls

Normal range for pulse pressure

• 30-50 mm

What causes an elevated pulse pressure?

caused by increased blood volume/heart rate, or a decrease in the ability of the arteries to expand.

3 possible problems caused by “elevated’ BP

1. Can harden arteries

2. Dislodge plaque

3. Block vessels that nourish the heart

What is the measurement for elevated BP?

When sys. = 120 & 129, dia. = <80

What is elevated BP a warning sign of?

high blood pressure will develop

2 ways to treat “elevated” BP (not medications)

proper nutrition, regular exercise

2 factors to consider when checking blood pressure that may affect accuracy and occurrence:

socioeconomic and psychological factors

• Stress: surge of hormones - cortisol (elevated BP, narrow blood vessels)

  • “white-coat” hypertension: when BP readings are higher at the doctor’s office than other settings

• Socioeconomic status

  • Less access to healthy food, higher BMI, stress of economic pressure

Define hypertension and its abbreviation

(HTN- high BP)

• indicated when pressures are greater than 130 mm Hg systolic and 80 mm Hg diastolic

Value for stage 1 hypertension and how it is treated

systolic b/w 130 &139 mm Hg or a diastolic b/w 80 & 89 mm Hg.

• only take meds if you had heart attack or stroke/underlying condition

  • Treatments: low sodium diet and exercise

Value for stage 2 hypertension and how it is treated

systolic >140 mmHg or a diastolic >90 mmHg

• treatments: lifestyle changes; medication

Value for hypertensive crisis, how it is treated, and potential complications

occurs when BP is measured at a sys. >180 mm Hg and/or a dia. >120

• treatments: immediate medication changes are indicated and possible immediate hospitalization if there are signs of organ damage

• can damage blood vessels and cardiovascular accident (CVA) or stroke

Common causes for hypertension that can also lead to hypertensive crisis

stress, anxiety, obesity, high salt intake, aging, kidney disease, thyroid deficiency, arteriosclerosis **vascular: arteries hardening

Why is HTN often called silent killer

b/c most people do not have any signs or symptoms of the disease.

What can happen if HTN is left untreated

If HTN is untreated, it can lead to stroke, kidney disease, and/or heart disease

Define hypotension, value, and causes

(low BP) pressures are less than 90 sys. & 60 dia.

• It may occur with heart failure, dehydration, depression, severe burns, hemorrhage and shock (cariogenic)

Define orthostatic (postural) hypotension

sudden drop in sys. & dia, when patient moves from a lying down to a sitting/standing position

What are the symptoms and causes of orthostatic hypotension

Causes: the inability of blood vessels to compensate quickly to change in position.

Symptoms: becomes light-headed and dizzy; may experience blurred vision. (Last a few sec till blood vessels push more blood to brain)

Factors that cause changes in BP readings

force of the heartbeat, resistance of the arterial system, elasticity of the arteries, volume of blood in the arteries, and position of patient

Factors that increase BP

excitement, anxiety, nervous tension, exercise, eating, pain, obesity, smoking, and/or stimulant drugs

Factors that decrease BP

Rest or sleep, depressant drugs, shock, dehydration, hemorrhage and fasting

3 types if sphygmomanometers …most accurate and least accurate

Used to measure BP in (mm Hg)

• 3 types: mercury, aneroid, and electronic

• Mercury is most accurate, but OSHA discourages this b/c of possible spill and contamination of mercury (Electronic is least accurate)

Unit for blood pressure measurement

mm Hg

How can you tell if aneroid is correctly calibrated?

It’s calibrated in mm Hg, each line is 2 mm Hg pressure. When the cuff is deflated, the needle must be on zero.

AHA recommendations for how to obtain an accurate BP

• patient sit quietly for at least 5 min. before BP is taken

• Also, 2 separate readings be taken and averaged with a min. wait of 30 sec. b/w readings

How cuff size effects measurement

(Cuff contains rubber bladder)

• too small - artificially high readings

• too large - artificially low readings

Cuff width and length of bladder to ensure correct fit

• Cuff width: 40% of the circumference of the patient’s upper arm.

• Length of bladder = 80% of the circumference on upper arm

Patient positions for measurements and arm location

Seated/lying comfortably; forearm supported on a flat surface (below heart level)

Correct position of cuff bladder and lower edge of cuff

Area of the arm covered by the cuff should be at heart level/ no constrictive clothing

• (fully deflated) cuff placed on the arm, center of the bladder in the cuff directly over brachial artery, and the lower edge of the cuff 1-1 ½ in. Above the antecubital (bend of elbow)

Position of stethoscope and technique

placed directly over the brachial artery at the antecubital area and held securely but with as little pressure as possible.

• ASK if there is difficulty getting reading, report abnormalties