BLOOD PRESSURE
MEASUREMENT IN CHILDREN
Mohammad Ilyas, M.D.
Director Hypertension Clinic
Arkansas Children’s Hospital
Division of Nephrology, Department of
Pediatrics. UAMS Little Rock
School Health Conference, Little Rock
Little Rock is the capitol of State of Arkansas
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7/19/07
A.
B.
False
True
Distribution of Hypertensive Patients
Adults
Children
2.5 million
47.5 million
7/19/07
Tracking of Blood Pressure


Bogalusa Heart Study showed 40% individuals
with SBP > 80th percentile at baseline had levels
above that 15 years later
The ability to predict BP levels in adulthood from
measurements in childhood would provide the
opportunity to intervene before hypertension is
established, thereby reducing the CVD risk.
(Lane et al. J Human Hypertension 2004)
7/19/07
Overweight and Hypertension in Children
Prevalence of Overweight in Children
Prevalence of Hypertension in School Children
4.50%
14%
4.00%
12%
3.50%
10%
1971-1974
1999-2000
8%
6%
Prevalence
Prevalence
5.00%
16%
3.00%
2.50%
1989
2004
2.00%
1.50%
4%
1.00%
2%
0.50%
0%
0.00%
6 to 11 years
12 to 19 years
Year
Age Group
Ogden CL et al. JAMA 2002
7/19/07
Sorof JM et al. Pediatrics 2004
Blood Pressure, in children, is most
commonly measured by:
A.
 B.
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Physicians
Nurses
Blood Pressure Measurement Training
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Why to train already trained personnel?
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Effect of Training on Observer
Errors
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Bruce NG et al. J Hypertens 1988; 6:375- 380
Outline
 History
(brief)
 Blood pressure measurement devices
 Procedure
 Definition of hypertension
 Practice cases
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Blood Pressure Measurement
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

Stephen Hales 1733
Hollow glass tube in
neck artery of horse
Blood rose 9 feet in
glass tube
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Medicine, an Illustrated History 1987
History of Blood Pressure
Measurement


1896. Scipione RivaRocci
Only Systolic BP
measured by palpation
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Medicine, an Illustrated History 1987
Blood Pressure Measurement - History

Cook and Briggs 1903
 Residents, Johns Hopkins
 Single size rubber bladder
 Arm size a “small factor”
 Systolic BP
 Children
 Adults
 korotkoff
7/19/07
75-90 (<2 yr) 90-110 (childhood)
130 (men)
120 (women)
Devices
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7/19/07
Which blood pressure apparatus is the “Gold
standard” for BP measurement in children above
age 3
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A.
B.
C.
D.
E.
DINAMAP
Oscillometric wrist BP monitor
Ambulatory BP monitor
Mercury sphygmanometer
Aneroid BP monitor
Mercury Sphygmomanometer
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Mercury Sphygmomanometry
1998: EPA and the American Hospital
Association agreed to virtually eliminate
mercury from hospitals by 2005
7/19/07
In the absence of a mercury manometer,
which is preferred method to measure BP
in children above age 3
A.
 B.
 C.
 D.

7/19/07
Oscillometric wrist BP monitor
Auscultatory aneroid BP monitor
Oscillometric arm BP monitor
DINAMAP
Aneroid Manometer


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Mercury pressure
gauge replaced by
mechanical spring
Gauges are often
small
Accuracy varies
among manufacturers
Requires frequent
calibration
7/19/07
Aneroid Manometers
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Mercury and Aneroid Manometer
7/19/07

How often should an aneroid BP monitor
be calibrated?
A.
 B.
 C.
 D.
 E.
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7/19/07
Once a day
Once a week
Once every 6 months
Once a year
Once every 5 years
Testing the Aneroid Manometer




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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
7/19/07
Which is preferred method to measure BP
in neonates and infants?
A.
 B.
 C.
 D.
 E.

7/19/07
Oscillometric wrist BP monitor
Auscultatory aneroid BP monitor
Oscillometric finger BP monitor
DINAMAP
Mercury sphygmanometer
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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Dinamap Oscillometric Device
®
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7/19/07
Dinamap® is an
acronym for:
Device for
Indirect
Noninvasive
Mean
Arterial
Pressure
Dinamap Oscillometric Device
®
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7/19/07
Dinamap® has been
widely used in pediatrics
Detects MAP and
estimates SBP and DBP
Proprietary algorithms
Accuracy decreases with
increased arterial
“stiffness”
Possible systematic
errors in diabetics
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
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Evaluation of the Dinamap 8100
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Rose et al (2000)*
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Noted from review of data from NHLBI studies that
Dinamap algorithm skipped certain values
ARIC Study: More than 180,000 individual BP
measurements
Never recorded SBP of 89, 119, 124, 125, 130, 140,
141, 150, 160, 170, 180, 190, 200 mmHg
No skip pattern for DBP
Skipped HR of 95, 99, 103, 106, 109 bpm
Rose KM et al Hypertens (2000); 35:1032-1036
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Oscillometric Devices
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Validated Monitors
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British Hypertension Society
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Association for the Advancement of
Medical Instrumentation (AAMI)
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www.hyp.ac.uk/bhs/blood_pressure_list
www.aami.org
dabl Educational trust
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7/19/07
www.dableducational.com
Ambulatory BP Monitoring
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Oscillometric or
acoustic methods
24 hour monitoring
Individual
measurements not
more accurate
Readings
downloaded into PC
Cost: $2500-4500
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Ambulatory Blood Pressure
Monitoring
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White Coat Hypertension
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Ambulatory Blood Pressure
Monitoring
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Procedure
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
What effect would you expect when taking
the blood pressure on an obese child with
a small BP cuff?
A. No effect
 B. Higher blood pressure
 C. Lower blood pressure
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Case History
12 years old boy
 Admitted for cellulitis of left lower leg
 BP= 210/110 mm Hg
 Blood pressure rechecked
 Physical examination, Wt. 587 pounds
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Blood Pressure Cuff size
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Blood Pressure Cuff Size
Index line
Cuff length = 80% of MAC
Bladder length (80%)
20%
MAC
Largest allowable mid arm
circumference for bladder (100%)
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Cuff width = 40% of MAC
Blood Pressure Cuff Size
NHANES 99-2002 Children
Child
Adult
Large adult
Thigh
80
70
60
71
57
50
(%)
51
40
37
30
20
10
0
30
25
3
0.5
3-8 yrs
11 0.7
9-14 yrs
9
4
15-19 yrs
35% of 4th and 8th graders needed large adult cuff in Marianna
7/19/07
Recommended Dimensions for BP Cuff
Bladders
Age range
Width
(cm)
4
Length
(cm)
8
Max. AC
(cm)
10
Infant
6
12
15
Child
9
18
22
Small adult
10
24
26
Adult
13
30
34
Large adult
16
38
44
Thigh
20
42
52
Newborn
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Blood pressure is measured in children
preferably on
A.
 B.
 C.
 D.
 E.
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Right lower leg
Left upper arm
Right upper arm
Left wrist
Right wrist

What is the optimal position for a patient’s
arm to be in when taking the blood
pressure?
A.
 B.
 C.
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7/19/07
D.
Cubital fossa at the heart level
Elbow at heart level
Elbow supported with midpoint of
upper arm at heart level
Elbow by the side of the body
Auscultatory Method
Fourth Report on BP in Children 2004
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Sitting quietly for 5 minutes
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Back supported and feet on the floor
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Right arm supported, cubital fossa at
heart level
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Estimate systolic BP by palpation, reinflate cuff to 20 mmHg higher
Pediatrics. August 2004
7/19/07
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What is the optimal rate of deflation of
blood pressure cuff?
A.
 B.
 C.
 D.
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1 mm Hg / sec
2-3 mm Hg / sec
5 mm Hg / sec
10 mm Hg / sec
Auscultatory Method
Fourth Report on BP in Children 2004
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Deflate cuff at 2-3 mmHg/sec
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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
Pediatrics1996;98:649-658
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Auscultatory Sounds
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Auscultatory Method
Fourth Report on BP in Children 2004
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
7/19/07
Blood Pressure In Children
Auscultation is preferred method
 Elevated BP must be confirmed on
repeated visits
 BP readings >90th obtained by
oscillometric devices, should be repeated
by auscultation
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Fourth report on BP. Pediatrics August 2004
7/19/07
Definition
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Hypertension- Definition
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Normal blood pressure:
less than 120/ 80 mmHg
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Pre-hypertension:
120 – 139/ 80 - 89 mmHg
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Hypertension:
Stage 1:
140 to 159 /90 to 99 mmHg
Stage 2:
160 mmHg / 100 mmHg
The JNC 7 report. JAMA 2003; 289:2560.
7/19/07
Pediatric BP Standards

Blood pressure correlates with:
Age
Gender
Height percentile

Standards
Ages 1-12 months: 1987 task force
Ages 1-17 years: Fourth BP report
Fourth report on BP. Pediatrics August 2004
7/19/07
Definitions
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Normal
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Pre-hypertension
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SBP and DBP <90th percentiles for gender,
age, and height
Average SBP or DBP between 90th and 95th
percentiles or > 120/80 mm Hg
Hypertension
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Average SBP and/or DBP > 95th for gender,
age, and height on more than 3 occasions
Fourth Report on BP. Pediatrics August 2004
5 yrs old
Girl
BP 121/80
Height 90th
percentile
90th :
109/69
95th :
112/73
Fourth Report on BP. Pediatrics August 2004
7/19/07
Definitions
Stage I hypertension
 Average SBP and/or DBP between 95th
and 99th percentile plus 5 mm Hg
 Stage II hypertension
 Average SBP and/or DBP > 99th
percentile plus 5 mm Hg
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Fourth Report on BP. Pediatrics August 2004
7/19/07
5 yrs old
Girl
BP 121/80
Height 90th
percentile
90th :
109/69
95th :
112/73
99th :
120/81
Stage II:
>125/86
Fourth Report on BP. Pediatrics August 2004
7/19/07
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A 7 years old boy had average BP 110/60
mm Hg. Similar BP readings were
documented on three separate occasions.
His height is at 95th percentile. This boy
has
A.
 B.
 C.
 D.
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7/19/07
Normal blood pressure
Pre-hypertension
Stage I hypertension
Stage II hypertension
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A 8 years old girl has average BP 130/90
mm Hg. Similar BP readings were
documented on three separate occasions.
Her height is at 75th percentile This girl has
A.
 B.
 C.
 D.
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7/19/07
Normal blood pressure
Pre-hypertension
Stage I hypertension
Stage II hypertension

A 11 years old boy had average BP 140/95
mm Hg. Similar BP readings were
documented on three separate occasions.
His height is at 5th percentile This boy has
A.
 B.
 C.
 D.
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7/19/07
Normal blood pressure
Pre-hypertension
Stage I hypertension
Stage II hypertension
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A 18 years old young man had average BP
150/95 mm Hg. Similar BP readings were
documented on three separate occasions.
His height is at 50th percentile This young
man has
A.
 B.
 C.
 D.
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Normal blood pressure
Pre-hypertension
Stage I hypertension
Stage II hypertension
Blood Pressure Screening in Marianna
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May 2005
Volunteers and school nurse was trained for BP
measurement
81, 4th grader (89% AA)
First screening
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Normal
80%
Pre-htn
9%
Hypertension 11%
Third screening
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Hypertension 3.7%
School Blood Pressure Screening
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Purpose
To find undiagnosed hypertensive school
children and adolescents
 Refer these children to primary care
physicians
 Help primary care physicians in the
management of these children if required
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Summary
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Accurate blood pressure measurement is the
corner stone of diagnosis of hypertension in
children
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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Thanks
Ms. Paula Smith
 Department of Pediatrics-UAMS
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
Office of education
Minority Health Commission
 Marianna School
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7/19/07
Hypertension Clinic-ACH
Dr. Karen McNiece, M.D
 Dr. Thomas Wells, M.D.
 Dr. Mohammad Ilyas, M.D.
 Jona Plummer, RNP
 Wendy Davis, RN
Contact Number
(501) 364-1847
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7/19/07