Blood Pressure Training

Kidney Disease Screening and Awareness Program (KDSAP)

Susan Cheung, MD, MS

Renal Division, Department of Medicine,

Harvard Medical School, Harvard University

Objectives

By the end of this session, you will learn and

demonstrate adequate techniques to measure

blood pressure correctly

Question 1:

What is Blood Pressure(BP)?

What is blood pressure (BP)?

• BP is the force of blood pushing

against the walls of arteries.

• BP is expressed as two numbers:

systolic/diastolic BP.

• Systolic BP: the pressure in the

blood vessel when the heart

beats

• Diastolic BP: the pressure in the

blood vessel when the heart is at

rest between beats

Question 2:

What is the normal BP?

• Currently used in the Clinical setting:

– Normal BP: < 130/80 mmHg

• According to AHA ( American Heart Association):

Definition of Hypertension

Question 3:

Why do we worry about high

blood pressure?

Complications of Persistent High

Blood Pressure

Complications of Persistent High

Blood Pressure

• Hypertensive Heart Disease:

(Left ventricular hypertrophy and cardiomegaly)

Complications of Persistent High

Blood Pressure

• Subarachnoid and intracerebral hemorrhage:

Complications of Persistent High

Blood Pressure

• Nephrosclerosis and chronic kidney disease (CKD):

Question 4:

What do you need to measure

BP?

Anatomy of Brachial Artery

1. Stethoscope

2. BP cuff

3. Patients

Stethoscope Anatomy

1. Check the

tubing for holes

2. Clean any wax

from the ear tips

3. Point earpieces

forward when

ready to use

Choosing the right size cuff1. Use the “bladder” of a blood pressure

cuff

2. Measure the circumference of the arm

80%

40%

Distance around the arm Blood pressure cuff size

7 to 9 inches Small adult cuff

9 to 13 inches Standard adult cuff

13 to 17 inches Large adult cuff

Check:

1. Screw valve

2. Air leak

Question 5:

What is the mechanics behind

measuring BP?

• You are indirectly measuring the pressure in the blood vessel

• When the pressure in that bladder exceeds the pressure of the artery, the artery is compressed and distal blood flow diminishes, then stops

• As you release the air in the cuff, the bladder deflates and cuff pressure falls

• Pressure in cuff reaches the pressure generated by the heart during contraction, blood begins to flow through the artery again

Mechanics Behind Measuring BP

• Blood flow produces

Korotkoff's sounds: these

sounds vary through 5 different

phases

• The cause of these sounds is still

debated: may be caused by

blood jetting through the partly

occluded vessel. The jetting

causes turbulence in the open

vessel beyond the cuff

Mechanics Behind Measuring BP

Korotkoff’s Sounds

• According to the American Heart Association,

Korotkoff's sounds occur in five phases:

Question 6:

How do we take an accurate BP?

• Check your equipment before you start

• Check the environment

– Make sure the environment is quiet and without disturbance

• Check your patient

– Make sure your patient is relaxed, if needed, have him sit or lie

down for 5 minutes.

– Ask your patient not to talk during measurement

– Remove all clothing from forearm

– Support your patient’s arm at heart level

– Ask about cigarettes, alcohol and caffeine intake in the last 15

minutes which may affect BP readings

• Check yourself

– Make sure the manometer is in your direct line of sight

– Make sure you are relaxed

– Keep your eyes not only on your equipment but also your

patients

– Deflate the cuff slowly, 2-3mmHg per sec, listen carefully for

the Korotkoff’s sounds

Accurate BP measurements

Questions?

• Step 1: Always introduce yourself! And put the patient at ease.

• Step 2: Appropriately expose and position patient's arm at heart level on table or

cradle

• Step 3: Select the right size cuff

• Step 4: Place cuff appropriately around patient’s arm and make sure manometer is

readily in sight and feel for brachial/radial artery:

Look! Look! Look!

• Step 5: Estimate systolic blood pressure by inflating the cuff and palpating the

brachial/radial artery

Look! and Feel!

• Step 6: Proper placement of cuff and place stethoscope over brachial artery and make

sure all equipment is appropriately positioned.

Look! Look! Look!

• Step 7: Deflate cuff and take systolic blood pressure (Korotkoff phase 1)

and diastolic blood pressure (Korotkoff phase 5)

Look and Listen!

• Step 9: Remove equipment as appropriate and address the patient

Protocol for BP Measurement

• Write down the BP reading:

systolic BP/diastolic BP ie: 140/90mmHg

• Two readings at least two minutes apart

• Be sure to tell your patient about their BP reading

Protocol for BP Measurement