blood pressure assessment and stroke 2009 preventing strokes one at a time
TRANSCRIPT
Blood Pressure Assessment and Stroke
2009
Preventing Strokes One At a Time
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
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
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
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
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
Modifiable Risks for Developing Hypertension
Obesity Poor dietary habits High sodium intake Sedentary lifestyle High alcohol consumption
2009 Canadian Hypertension Education Program Recommendations
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
Question
What is the office blood pressure target for a patient with diabetes and/or renal disease?
a. < 140/90b. < 135/85c. < 160/100d. < 130/80e. < 120/80
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
Question
By how many mmHg do you need to lower blood pressure in order to decrease CV risk?a. 2 mmHgb. 5 mmHgc. 10 mmHgd. 15 mmHge. 20 mmHg
Question
At what blood pressure does the risk for cardiovascular disease and stroke start to increase?
a. > 140/90b. > 130/80c. > 110/75d. < 150/95e. < 120/85
Blood Pressure Measurement
Office (OBPM) Home (HBPM) Ambulatory Blood Pressure
Monitoring (ABPM)
2009 Canadian Hypertension Education Program Recommendations
Resting Blood Pressure MeasurementDoing it Right!
Recommendations
Question
How long should a patient rest prior to taking a resting blood pressure measurement?
a. 1 minuteb. 2 minutesc. 5 minutesd. 10 minutese. No rest is required
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
Observer
Positioned comfortably to obtain measurement
Manometer at eye level Well maintained stethoscope Clean earpieces
2009 Canadian Hypertension Education Program Recommendations
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 pain2009 Canadian Hypertension Education Program Recommendations
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
Recommended Equipment for Measuring Blood Pressure
Mercury manometer Recently calibrated aneroid
Validated automated device
2009 Canadian Hypertension Education Program Recommendations
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
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 size2009 Canadian Hypertension Education Program
Recommendations
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
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
Palpation
Determine systolic blood pressure by palpation to decrease pain and exclude possibility of systolic auscultatory gap1. Palpate the radial pulse2. 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
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 2Auscultatory
gapNo sound
mm Hg
Korotkoff sounds
2009 Canadian Hypertension Education Program Recommendations
Auscultation
1. Palpate, then place stethoscope over brachial artery2. Inflate cuff pressure to the MIL3. Deflate cuff pressure by 2 mmHg per second
Appearance of 2 regular tapping sounds Korotkoff phase I = systolic pressure
4. Continue to decrease pressure by 2 mmHg per second
Disappearance of soundKorotkoff phase V = diastolic pressure
5. If DBP>90 mmHg listen for an additional 30mmHg to rule out Diastolic auscultatory gap
6. Record measurement
2009 Canadian Hypertension Education Program Recommendations
The Concept of White Coat vs Masked Hypertension
From Pickering et al, Hypertension 2002
Office SBP mmHg
Hom
e o
r A
BPM
SB
P m
mH
g
TrueHypertensive
TrueNormotensiv
e
White Coat Hypertension
MaskedHypertension
135
140
135
140
2009 Canadian Hypertension Education Program Recommendations
The Prognosis of Masked hypertension
0
0.5
1
1.5
2
2.5
Normotension White CoatHypertension
MaskedHypertension
Hypertension
Relatve riskof 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
Question
What is the target home blood pressure for a patient without Diabetes Mellitus or Chronic Kidney Disease?
a. < 120/80b. < 125/75c. < 130/80d. < 135/85e. < 140/90
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
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
hypertension2009 Canadian Hypertension Education Program Recommendations
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
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/bilingualposterorderform.pdf
2009 Canadian Hypertension Education Program Recommendations
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
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
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
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
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
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 hypertensiono Assessmento Treatmento Blood pressure measurement
Patient Resources: www.hypertension.ca/bpc o How to take a proper blood pressureo Home blood pressure monitorso Patient education
2009 Canadian Hypertension Education Program Recommendations
Canadian Best Practice Recommendations for Stroke Care, updated 2008
www.canadianstrokestrategy.ca