BP and stroke

1. Blood Pressure Assessment
and Stroke
2009
Preventing Strokes One At
a Time

2. Blood Pressure & Stroke
Upon completion, participants will be able to:
 Practice according to the Canadian Best Practice
Recommendations for Stroke Care as they relate
to blood pressure
 Discuss the impact of hypertension on stroke risk
 Use proper technique when taking a blood
pressure
 Monitor and interpret blood pressure reading
according to Canadian Hypertension Education
Program recommendations
 Teach patient the why & how of proper blood
pressure measurement
LEARNING OBJECTIVES

3. Blood Pressure & Stroke
 Hypertension Overview
 Blood Pressure Targets
 Blood Pressure Measurement
 Office
 Home
 Ambulatory Blood Pressure Monitor
Content from the following slides is derived from
the Canadian Hypertension Education
Program Recommendations, 2009
www.hypertension.ca/blood pressurec
Outline

4. Blood Pressure
2.2a Blood Pressure Assessment
 All persons at risk for stroke should have their blood
pressure measured at each healthcare encounter but
no less than once annually.
 Proper standardized techniques, as described by
the Canadian Hypertension Education Program,
should be followed for blood pressure measurement
 Patients found to have elevated blood pressure should
undergo thorough assessment for the diagnosis of
hypertension following the current guidelines of the
Canadian Hypertension Education Program.
 Patients with hypertension or at risk for hypertension
should be advised on lifestyle modifications.
CMAJ 2008;179(12 Suppl):E1-E93.
Canadian Best Practice Recommendations for Stroke Care, 2008

5. Blood Pressure
2.2b Blood Pressure Management
 The Canadian Stroke Strategy recommends target blood
pressure levels as defined by CHEP guidelines for
prevention of first stroke, recurrent stroke and other
vascular events.
 For prevention of first stroke in the general population the
systolic blood pressure treatment goal is a pressure level of
less than 140 mm Hg
 The diastolic blood pressure treatment goal is a pressure
level of less than 90 mm Hg
 Blood pressure lowering treatment is recommended for
patients who have had a stroke or transient ischemic attack
to a target of less than 140/90 mm Hg
 In patients who have had a stroke, treatment with an
angiotensin-converting enzyme (ACE) inhibitor and diuretic
is preferred
CMAJ 2008;179(12 Suppl):E1-E93.
Canadian Best Practice Recommendations for Stroke Care, 2008

6. 2.2b Cont’d
 Blood pressure lowering treatment is recommended for the
prevention of first or recurrent stroke in patients with diabetes
to attain systolic blood pressures of less than 130 mm Hg and
diastolic blood pressures of lower than 80 mm Hg
 Blood pressure lowering treatment is recommended for the
prevention of first or recurrent stroke in patients with non
diabetic chronic kidney disease to attain systolic blood
pressures of less than 130 mm Hg and diastolic blood
pressures of lower than 80 mm Hg
 RCTs have not defined the optimal time to initiate BP lowering
therapy after stroke or TIA. It is recommended that blood
pressure lowering treatment be initiated (or modified) before
discharge from hospital.
 For recommendations on specific agents and sequence of
agents refer to the current CHEP guidelines
www.hypertension.ca/chep

7. Modifiable Risks for Developing
Hypertension
 Obesity
 Poor dietary habits
 High sodium intake
 Sedentary lifestyle
 High alcohol consumption
2009 Canadian Hypertension Education Program Recommendations

8. Challenges to Hypertension Management:
Public Perceptions
 80% of people were unaware of the
association between hypertension and
CVD
 63% believed that hypertension was not a
serious condition
 38% of people thought they could control
high blood pressure without the help of a
health professionalCan J Cardiol 2005;21:589-
93
2009 Canadian Hypertension Education Program Recommendations

9. Question
What is the office blood pressure target for a
patient with diabetes and/or renal disease?
a. < 140/90
b. < 135/85
c. < 160/100
d. < 130/80
e. < 120/80

10. Blood Pressure Targets for the
Treatment of Hypertension
Condition Target
Isolated systolic hypertension <140 mmHg
Systolic/Diastolic Hypertension
• Systolic blood pressure
• Diastolic blood pressure
<140 mmHg
<90 mmHg
Diabetes or Chronic Kidney Disease
• Systolic
• Diastolic
<130 mmHg
<80 mmHg
2009 Canadian Hypertension Education Program Recommendations

11. Question
By how many mmHg do you need to lower
blood pressure in order to decrease CV
risk?
a. 2 mmHg
b. 5 mmHg
c. 10 mmHg
d. 15 mmHg
e. 20 mmHg

12. Question
At what blood pressure does the risk for
cardiovascular disease and stroke start to
increase?
a. > 140/90
b. > 130/80
c. > 110/75
d. < 150/95
e. < 120/85

13. Blood Pressure Measurement
 Office (OBPM)
 Home (HBPM)
 Ambulatory Blood Pressure Monitoring
(ABPM)
2009 Canadian Hypertension Education Program Recommendations

14. Resting Blood Pressure Measurement
Doing it Right!
Recommendations

15. Question
How long should a patient rest prior to taking
a resting blood pressure measurement?
a. 1 minute
b. 2 minutes
c. 5 minutes
d. 10 minutes
e. No rest is required

16. Types of Readings
 Casual blood pressure - a measurement
taken without the required 5 minute rest
period
 Resting blood pressure - the seated
resting blood pressure is used to
determine and monitor treatment decisions
 Standing blood pressure - is used to test
for postural hypotension, which may
modify treatment if present
2009 Canadian Hypertension Education Program Recommendations

17. Observer
 Positioned comfortably to obtain
measurement
 Manometer at eye level
 Well maintained stethoscope
 Clean earpieces
2009 Canadian Hypertension Education Program Recommendations

18. Patient Preparation
 No caffeine for 30 – 60 minutes
 No smoking for 30 minutes
 No exercise for 30 minutes
 Bladder/Bowel comfortable
 Quiet/temperate, relaxed environment, no talking
 Bare arm with no constrictive clothing
 Patient should stay silent prior and during the
procedure
 No acute anxiety, stress or pain
2009 Canadian Hypertension Education Program Recommendations

19. Posture
 Calmly seated for 5 minutes
 Back well supported
 Arm relaxed & supported at
heart level
 Legs uncrossed, feet flat on
the floor
2009 Canadian Hypertension Education Program Recommendations

20. Recommended Equipment for
Measuring Blood Pressure
Mercury manometer Recently calibrated aneroid
Validated automated device
2009 Canadian Hypertension Education Program Recommendations

21. BpTRU
 Automated, non invasive monitor that measures
blood pressure and pulse in patients using upper
arm cuff
 Device automatically inflates and deflates the cuff
 Uses oscillometric technique
 Has 2 operational modes
 Manual mode to take one blood pressure
measurement
 Automatic mode takes 6 measurements,
discards the first, and displays the average of
the next 5 readings.
Product Overview
2009 Canadian Hypertension Education Program Recommendations

22. Cuff Size
 Measure arm circumference midpoint b/w
shoulder and elbow
 Bladder must encircle at least 80% of arm
circumference
 Lower edge of cuff placed 2-3 cm above
elbow crease
 Bladder centered over the brachial artery
 Tell patient their cuff size
2009 Canadian Hypertension Education Program Recommendations

23. Cuff Position & Dimensions
(no standardization between manufacturers)
 Locate the brachial pulse and centre the cuff
bladder over it
 Position cuff at heart level.
Circumference of Adult Arm Size of Bladder (cm)
18-26 cm 9x18 (Child)
> 26-33 cm 12x23 (Regular Adult)
> 33-41 cm 15X33 (Large)
> 41 cm 18x36 (Extra Large)
2009 Canadian Hypertension Education Program Recommendations

24. Office Technique
 On initial visit, blood pressure should be taken in
both arms and subsequently it should be
measured in the arm with the highest reading.
Inform the patient
 Duplicate, resting readings, 1 – 2 minutes apart,
should be taken at each visit
 If readings vary by > 5mmHg, the readings should
be repeated until 2 consecutive readings are
comparable
 Standing blood pressure @ 1 & 3 minutes
2009 Canadian Hypertension Education Program Recommendations

25. Palpation
 Determine systolic blood pressure by palpation to
decrease pain and exclude possibility of systolic
auscultatory gap
1. Palpate the radial pulse
2. Inflate quickly to 60 mmHg and then by increments of
10mmHg until the pulse disappears = estimated
palpated systolic pressure
3. Slowly deflate at a rate of 2 mmHg/second until the
pulse reappears to confirm your palpated systolic
pressure
4. Add 30 mmHg to this number to determine you
Maximum Inflation Level (MIL)
2009 Canadian Hypertension Education Program Recommendations

26. Korotkoff Sounds and Auscultatory Gap
Systolic blood pressure
200
180
160
140
120
100
80
60
40
20
0
No sound
Clear sound
Clear sound
Muffled sound
No sound
Phase 1
Phase 3
Phase 4
Phase 5
Muffling Phase 2
Auscultatory
gapNo sound
mm Hg
Korotkoff sounds
2009 Canadian Hypertension Education Program Recommendations

27. Auscultation
1. Palpate, then place stethoscope over brachial artery
2. Inflate cuff pressure to the MIL
3. Deflate cuff pressure by 2 mmHg per second
Appearance of 2 regular tapping sounds
Korotkoff phase I = systolic pressure
1. Continue to decrease pressure by 2 mmHg per second
Disappearance of sound
Korotkoff phase V = diastolic pressure
1. If DBP>90 mmHg listen for an additional 30mmHg to rule
out Diastolic auscultatory gap
2. Record measurement
2009 Canadian Hypertension Education Program Recommendations

28. The Concept of White Coat vs
Masked Hypertension
From Pickering et al, Hypertension 2002
Office SBP mmHg
HomeorABPMSBPmmHg
True
Hypertensive
True
Normotensive
White Coat
Hypertension
Masked
Hypertension
135
140
135
140
2009 Canadian Hypertension Education Program Recommendations

29. The Prognosis of Masked hypertension
0
0.5
1
1.5
2
2.5
Normotension White Coat
Hypertension
Masked
Hypertension
Hypertension
Relatve risk
of CVD
J Hypertension 2007;25:2193-98
Prevalence of masked hypertension is approximately 10% in the
general population (prevalence is higher in diabetic patients).
2009 Canadian Hypertension Education Program Recommendations

30. Question
What is the target home blood pressure for a
patient without Diabetes Mellitus or
Chronic Kidney Disease?
a. < 120/80
b. < 125/75
c. < 130/80
d. < 135/85
e. < 140/90

31. OBPM HBPM, ABPM Equivalence
A clinic blood pressure of 140/90 mmHg has a similar risk of a:
Description Blood Pressure mmHg
Home pressure average 135 / 85
Daytime average ABP 135 / 85
24-hour average ABP 130 / 80
2009 Canadian Hypertension Education Program Recommendations

32. Important Role for Home Blood Pressure
Measurement
 Measuring blood pressure at home has a stronger
association with CV prognosis than office based
readings
 Home measurement can help to:
 confirm the diagnosis of hypertension
 improve blood pressure control
 reduce the need for medications
 improve medication adherence in non adherent patients
 help to identify white coat and masked hypertension
2009 Canadian Hypertension Education Program Recommendations

33. Home Measurement of Blood Pressure:
Use Validated Blood Pressure
Measurement Devices
This logo* on the packaging
ensures that this type of
device and model meets the
international standards for
accurate blood pressure
measurement
* Endorsed by the Canadian Hypertension Society
2009 Canadian Hypertension Education Program Recommendations

34. Home measurement of blood pressure
A poster and instruction
sheets can be ordered at
the Heart and Stroke
Foundation offices or on-
line at:
http://hypertension.ca/bpc/
wp-
content/uploads/2008/03/bil
ingualposterorderform.pdf
2009 Canadian Hypertension Education Program Recommendations

35. Patient Instructions
 Use a validated monitor
 Correct cuff size
 Accurate resting technique
 Patient technique should be reviewed regularly
 Duplicate measurements 1-2 min. apart
 7 days after any Rx change or before a doctor’s
appointment
 AM (before Rx) & PM (2 hrs. after dinner)
2009 Canadian Hypertension Education Program Recommendations

36. Ambulatory Blood Pressure Monitor
(ABPM)
 Shows blood pressure pattern over a 24
hour period
 Measures blood pressure through
oscillometric technology which depends on
the pulsatility in the brachial artery
 Arm must stay motionless during inflation
and deflation
 Less accurate at extremes of systolic and
diastolic blood pressure
36
2009 Canadian Hypertension Education Program Recommendations

37. Diurnal Pattern/Circadian Rhythm
 Abnormalities in pattern are associated
with increased CV events
 Dipping is good
 Circadian rhythm of blood pressure is a >10%
fall in blood pressure during sleep
 A non-dipping pattern is associated with
an increase risk of MI, stroke, dementia as
blood pressure remains elevated during
sleep
2009 Canadian Hypertension Education Program Recommendations

38. Benefits 24 hour ABPM
 Provides large number of blood pressure readings outside
clinic setting
 Helps determine the dynamic changes of blood pressure
throughout 24 hour period
 Enables physician to adjust treatment appropriately to
prevent target organ complications
 Rules out ‘White Coat’ hypertension
 Used to aid in diagnosis of ‘Masked Hypertension’
 Identifies ‘Dippers’ vs. ‘Non-dippers’
2009 Canadian Hypertension Education Program Recommendations

39. Take Home Message
To take accurate blood pressure readings you must
ensure:
1. Proper cuff size
2. Validated monitor
3. Accurate resting technique
Both in the doctor’s office and at home!
2009 Canadian Hypertension Education Program Recommendations

40. Blood Pressure
 www.heartandstroke.ca/BP
 To monitor home blood pressure and encourage self
management of lifestyle
 www.hypertension.ca CHEP, 2009 Resources
 Health Professional Resources:
o Diagnosis of hypertension
o Assessment
o Treatment
o Blood pressure measurement
 Patient Resources: www.hypertension.ca/bpc
o How to take a proper blood pressure
o Home blood pressure monitors
o Patient education
2009 Canadian Hypertension Education Program Recommendations

41. Canadian Best Practice Recommendations for Stroke Care, updated 2008
www.canadianstrokestrategy.ca