Measuring and Recording
Blood Pressure
Health Science Technology
Mrs. J. Hanna, RN
Blood Pressure-BP
• Measurement of pressure that the blood
exerts on the artery walls during the
various stages of heart activity.
• Measured in mmHg on instrument called a
sphygmomanometer. (blood pressure cuff)
Two types of BP
• Systolic-top#-first beat heard
• Diastolic-bottom #-last beats
heard
Systolic Pressure
• Systolic pressure occurs in artery walls
when the L ventricle of the heart is
contracting and pushing blood into the
arteries.
• Normal systolic reading is 120 mmHg
• Normal range is 100-140 mmHg
Diastolic Blood Pressure
• Diastolic pressure-constant pressure in
artery walls when L ventricle of heart is at
rest or between contractions.
• Volume of blood in arteries has
decreased.
• Normal reading: 80mm/Hg
• Normal range: 60-90 mm/Hg
Pulse Pressure
• Difference between systolic and diastolic
pressure
• Normal range in adults is 30 to 50 mm/Hg.
• Example: Systolic pressure is 120 mm/Hg
and diastolic pressure is 80 mm/Hg, the
pulse pressure is 40 mm/Hg. (120-80=40)
HYPERTENSION
• High blood pressure
• When pressures are greater than
140 mm/Hg systolic and 90 mm/Hg
diastolic
Common Causes: stress, anxiety, kidney
disease, aging, high-salt intake, thyroid
deficiency, and vascular conditions.
HYPOTENSION
• Low blood pressure when pressures are
less than 100 mm/Hg systolic and
60 mm/Hg diastolic.
Common Causes: heart failure, hemorrhage,
dehydration, depression, severe burns.
Orthostatic Hypotension
• Postural hypotension-occurs when there is
a sudden drop in both systolic and
diastolic pressure.
• This occurs when the individual moves
from a lying to a sitting or standing
position.
• Caused by inability of blood vessels to
compensate quickly to the change in
position.
Various Factors Influences
BP Readings
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Force of heartbeat
Resistance of the arterial system
Elasticity of the arteries
Volume of the blood in arteries
Various Factors Causing
Increased BP
1. excitement, anxiety, nervous tension
2. Exercise and eating
3. smoking
Various Factors Causing
Decreased BP
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•
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•
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Rest or sleep
Depressant drugs
Shock
Excessive loss of blood
Fasting
Factor that may cause changes
• Lying down
• Sitting position
• Standing position
Recording BP
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•
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Record as a fraction.
Systolic is the top number
Diastolic is the bottom number
120/80
Two main types of
sphygmomanometers
• Mercury sphygmomanometer-has long
column of mercury
• Each mark represents 2 mmHg.
• Aneroid has round gauge
• Cuff deflated=zero for accuracy
• *Electronic types used in healthcare
facilities.
Recommendations
• AHA-American Heart Assn. recommends
pt. sit quietly for @ least 5 min. before
taking BP.
• AHA recommends that two readings be
taken, averaged, with a minimum wait of
30 seconds between readings.
• Pt. seated or lying comfortably with
forearm supported on flat surface.
Procedure
• Cuff appropriate size for pt.
• Arm free of restrictive clothing
• Deflated cuff should be placed on arm with
center of cuff directly over the brachial
artery.
• Lower edge of cuff should be 1-1 ½ inches
above the bend of the elbow.
Rest of the procedure
• Final point-accuracy in placing
stethoscope bell or diaphragm directly
over the brachial artery at the antecubital
area (bend in the elbow).
• Hold securely but with slight pressure.
• NEVER DISCUSS ANY READING OR VS
READING WITH A PT/RESIDENT!
Do not use
• Arm with IV
• Arm with paralysis
Reflection
• Your resident’s blood pressure is
186/110.
• Discuss with a partner what this
means and what your next step would
be.
• Explore some of the questions you
might want to ask the resident if he
were at home or at a community
event.