1. HYPERTENSION
Measurement of Blood Pressure
Mohammad Ilyas, M.D.
Assistant Clinical Professor
University of Florida / Health Sciences Center
Jacksonville, Florida USA
6/30/2014
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2. Outline
1. Definition, Regulation and Pathophysiology
2. Measurement of Blood Pressure, Staging of Hypertension and Ambulatory
Blood Pressure Monitoring
3. Evaluation of Primary Versus Secondary
4. Sequel of Hypertension and Hypertension Emergencies
5. Management of Hypertension (Non-Pharmacology versus Drug Therapy)
6. The Relation Between Hypertension: Obesity, Drugs, Stress and Sleep
Disorders.
7. Hypertension in Renal diseases and Pregnancies
8. Pediatric, Neonatal and Genetic Hypertension
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3. History of Blood Pressure Measurement
Stephen Hales 1733
Hollow glass tube in neck
artery of horse
Blood rose 9 feet in glass tube
Medicine, an Illustrated History 1987
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4. History of Blood Pressure Measurement
1896. Scipione Riva-Rocci
Only Systolic BP measured
by palpation
Medicine, an Illustrated History 1987
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5. Measurement of Blood Pressure
Correct measurement and interpretation of the blood
pressure (BP) is essential in the diagnosis and management
of hypertension.
It is essential that BP machines are properly calibrated,
appropriate cuff sizes are selected, and,
when BP is measured in an office-based setting
personnel are properly trained and
the patient is positioned correctly.
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6. Measuring accurate BP’s
Cuff too small → falsely high reading
Cuff too big → OK reading or no reading
(usually not falsely low)
Lower extremities - Normally, BP is 10 to 20
mmHg higher in the legs than the arms
Prefer arm if at all possible
Right arm for comparison with standards
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7. Blood Pressure Cuff size
• Bladder width >
40% of mid-arm
circumference.
• Bladder length
80-100% of arm
circumference.
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8. Blood Pressure Cuff Size
Index line
Bladder length (80%) 20%
Largest allowable mid arm
circumference for bladder (100%)
MAC = Mid Arm Circumference
Cuff length = 80% of MAC
Cuff width = 40% of MACMAC
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9. Confirming High BP’s
Repeat BP in both arms and one leg (both
not usually necessary)
Repeat 3 times to assure accurate
Dx of HTN requires elevated BP’s on 3
separate occasions
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11. METHODS FOR THE DIAGNOSIS OF
HYPERTENSION
Hypertension can be diagnosed using one of the
following three acceptable measurement
strategies:
Office-based blood pressure measurements
Home blood pressure monitoring
Ambulatory blood pressure monitoring (ABPM)
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12. Effect of Training on Observer Errors
Bruce NG et al. J Hypertens 1988; 6:375- 380
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13. New Blood Pressure Norms
OPTIMAL
<120 and <80
HIGH NORMAL
130-139 or 85-89
STAGE 1
140-159 or 90-99
STAGE 2
160-179 or 100-109
STAGE 3
≥180 or ≥110
NORMAL
<130 and <85
NORMAL
<120 and <80
PRE-HYPERTENSION
120-139 OR 80-89
STAGE 2
≥160 or ≥100
STAGE 1
140-159 or 90-99
JNC 7 (2003) JNC 8 (2013)JNC 6 (1997)
Hypertension
JNC VI. Arch Intern Med. 1997;157:2413-2446
JNC 7. JAMA. 2003;289(19):2560-2572.
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14. New Blood Pressure Norms for Children
Normotensive
Average SBP and DBP <90th % for age, sex and
height
Pre-hypertension
Average SBP or DBP >90th but <95th percentile
(OR >120/80)
Hypertension
Average SBP and/or DBP >95th percentile for
age, sex and height on 3 separate occasions
Stage 1: 95th-99th percentile + 5 mmHg
Stage 2: >99th percentile + 5 mm Hg
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15. How to use the percentile tables?
Need:
Age, gender, height percentage
BP charts
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16. 7 yo boy
Ht 75%tile
http://www.cc.nih.gov/ccc/pedweb/pedsstaff/bptable1.PDF
50% 99/58
90% 113/73
95% 119/80
99% 127/88
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17. BP tables for Infants
*Task Force on Blood Pressure Control in Children. Report of the Second Task Force on Blood Pressure Control in Children—1987.Pediatrics.1987;79:1–25(PR)
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20. Which blood pressure apparatus is the “Gold standard”
for BP measurement in children above age 3?
A. DINAMAP
B. Oscillometric wrist BP monitor
C. Ambulatory BP monitor
D. Mercury sphygmanometer
E. Aneroid BP monitor
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22. Mercury Sphygmomanometry
1998: EPA and the American Hospital
Association agreed to virtually eliminate
mercury from hospitals by 2005
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23. Aneroid Manometer
Mercury pressure gauge
replaced by mechanical
spring
Gauges are often small
Accuracy varies among
manufacturers
Requires frequent calibration
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26. Testing the Aneroid Manometer
Does the needle rest at zero?
Inflate to 200 mm Hg. Wait for 1
minute, if lower than 170 suspect
leak
Using the Y connector, connect
to mercury device and check
readings
If any reading is off by >4 mm,
remove from service
Date the calibration
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27. Oscillometric Devices
Office Use
Expensive (approximately $3000)
Many have been validated (BHS, AAMI)
Recommended for children of all ages
Home Use
Relatively inexpensive
Few have been validated in children
Not recommended for ages < 4 years
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28. Oscillometric Devices
Measure mean arterial pressure (MAP)
and calculates SBP and DBP
The algorithms used are proprietary and NOT
standardized
Results can vary widely and they do not
always closely match BP values obtained by
auscultation
These machines must be calibrated regularly
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30. Manual vs. Automatic
Manual is the gold standard
Oscillometric measurements preferred in infants
and ICU settings ONLY
All high readings should be confirmed with a
manual
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32. What is being measured?
Auscultatory method: relies on relationship
between audible Korotkoff sounds and pressure
at systole and diastole
Oscillometric method: relies on the amplitude of
oscillations in the arterial wall to determine MAP
(maximum amplitude); complex and proprietary
algorithms used to estimate SBP and DBP
Mean arterial pressure (MAP) is average pressure
throughout the cardiac cycle.
MAP=(SBP)+2(DBP)/3
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33. Ambulatory BP Monitoring
Oscillometric or acoustic methods
24 hour monitoring
Individual measurements not
more accurate
Readings downloaded into PC
Cost: $2500-4500
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37. Blood pressure is measured in preferably
on ?
A. Right lower leg
B. Left upper arm
C. Right upper arm
D. Left wrist
E. Right wrist
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38. Auscultatory Method
Sitting quietly for 5 minutes
Back supported and feet on the floor
Right arm supported, cubital fossa at
heart level
Estimate systolic BP by palpation, re-inflate
cuff to 20 mmHg higher
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39. What is the optimal rate of deflation of
blood pressure cuff?
A. 1 mm Hg/sec
B. 2-3 mm Hg/sec
C. 5 mm Hg/sec
D. 10 mm Hg/sec
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40. Auscultatory Method
Deflate cuff at 2-3 mmHg/sec
Systolic BP= onset tapping sounds*
Diastolic BP= disappearance of sounds (fifth
Korotkoff sound)
Record BP twice on each occasion as right arm,
sitting, SBP/DBP(K5), average used to estimate
BP level
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42. Auscultatory Method
DBP is determined by disappearance of
Krotkoff sounds (K5)
Sometime Krotkoff sounds heard till 0 mm Hg
Try less pressure on the head of stethoscope
If K5 still persists K4 should be recorded as DBP
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Fourth report on BP. Pediatrics August 2004
43. Summary
Accurate blood pressure measurement is the
corner stone of diagnosis of hypertension
Oscillatory method can be used for screening but
elevated blood pressure should be confirmed with
auscultatoy method
Appropriately sized cuff is mandatory and measure
mid arm circumference to choose the cuff size
Calibrate BP measurement apparatus semiannually
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45. Quiz 1. When Measuring the Blood Pressure
all statement below are true EXCEPT
A. Correct measurement of the blood pressure (BP) is
essential in the diagnosis and management of
hypertension.
B. It is essential that BP machines are properly calibrated.
C. Appropriate cuff sizes are needed for children
D. When BP is measured in an office-based setting,
personnel training does not interfere the measurement.
E. The position of patient impact the BP readings.
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46. Quiz 1. When Measuring the Blood Pressure
all statement below are true EXCEPT
A. Correct measurement of the blood pressure (BP) is
essential in the diagnosis and management of
hypertension.
B. It is essential that BP machines are properly calibrated.
C. Appropriate cuff sizes are needed for children
D. When BP is measured in an office-based setting,
personnel training does not interfere the measurement.
E. The position of patient impact the BP readings.
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47. Quiz 2. All statements below are true,
EXCEPT
A. Cuff too small lead to falsely high BP reading
B. Cuff too big usually not lead to falsely low BP
reading
C. Lower extremities BP reading is 10 to 20 mmHg
lower than the arms
D. Right arm is the prefer arm if at all possible
E. Right arm for comparison with standards
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48. Quiz 2. All statements below are true,
EXCEPT
A. Cuff too small lead to falsely high BP reading
B. Cuff too big usually not lead to falsely low BP
reading
C. Lower extremities BP reading is 10 to 20 mmHg
lower than the arms
D. Right arm is the prefer arm if at all possible
E. Right arm for comparison with standards
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49. Quiz 3. Which of the following Staging of
Hypertension is not TRUE ?
A. Normal Blood pressure is systolic <120 and
diastolic < 80
B. Pre hypertension include systolic 120-140 and
diastolic 80-90
C. Stage 1 hypertension is systolic > 150
D. Stage 1 hypertension is diastolic > 90
E. Stage 2 hypertension is Systolic > 160
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50. Quiz 3. Which of the following Staging of
Hypertension is not TRUE ?
A. Normal Blood pressure is systolic <120 and
diastolic < 80
B. Pre hypertension include systolic 120-140 and
diastolic 80-90
C. Stage 1 hypertension is systolic > 150
D. Stage 1 hypertension is diastolic > 90
E. Stage 2 hypertension is Systolic > 160
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51. QUIZ 4. What is being measured?
TRUE / FALSE
A. Auscultatory method relies on relationship between
audible Korotkoff sounds and pressure at systole and
diastole.
B. Oscillometric method relies on the amplitude of
oscillations in the arterial wall to determine MAP
(maximum amplitude).
C. Mean arterial pressure (MAP) is average pressure
throughout the cardiac cycle.
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52. QUIZ 4. What is being measured?
TRUE / FALSE
A. Auscultatory method relies on relationship between
audible Korotkoff sounds and pressure at systole and
diastole. TRUE
B. Oscillometric method relies on the amplitude of
oscillations in the arterial wall to determine MAP
(maximum amplitude). TRUE
C. Mean arterial pressure (MAP) is average pressure
throughout the cardiac cycle. TRUE
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