Blood pressure, measurements, methods, JNC recomendations

1. Blood Pressure.
Dr. Debashis Priyadarshan Sahoo
PGT, First year
Department of General medicine
NEIGRIHMS

2. Definition:
• Arterial blood pressure can be defined as the lateral pressure exerted
by moving column of blood on the walls of arteries.
1. It ensures blood flow to various organs.
2. It has important role in gas and nutrient exchange across capillaries.
3. Required for formation of urine and lymph.

3. • Systolic blood pressure: maximum BP in the arteries attainable during
systole.
• Diastolic blood pressure: minimum blood pressure obtained at the end of
the ventricular diastole.
• Pulse pressure: difference between systolic and diastolic blood pressure.
• Mean arterial blood pressure: DBP+ 1/3 pulse pressure.

4. Recording of blood pressure:
2 methods: Direct method and Indirect method.
1. Direct method: Invasive method
2. Indirect methods: Palpatory method and Auscultatory method

5. Recommended blood pressure measuring
techniques :
• BP should be measured in sitting position and patient should sit for 5 minutes
before measurement. For elderly patients and eliciting postural hypotension,
supine position can be used.
• Length of bladder should be approximately 80% of total length and 40% of total
circumference of upper arm.
• In antecubital fossa brachial artery is palpated and stethoscope is put on that area
for Korotkoff sound.
• Wrap the cuff approximately 2.5inch above the antecubital fossa.

7. Instruments:
• Aneroid
sphigmomanometer
This Photo by Unknown Author is licensed under CC BY-SA
This Photo by Unknown Author is licensed under CC BY-SA

8. Methods:
• Palpatory method: Deflate the cuff fully, wrap the cuff around the arm, feel the radial pulse,
inflate the cuff until radial pulse disappears, inflate the cuff 30-40mm over and release the pressure
slowly till the pulse reappears. This is the systolic blood pressure. Diastolic blood pressure cannot
be measured by palpatory method.
• Auscultatory method: Keep the bell of stethoscope over brachial artery and inflate the cuff to a
level higher than the systolic blood pressure determined by palpatory method. Slowly deflate the
cuff and record the systolic and diastolic blood pressure for determining systolic and diastolic
blood pressure based on Korotkoff sound. 5 types of Korotkoff sounds are heard. Tapping
sound(Korotkoff 1) is SBP and No sound(Korotkoff 5) is DBP

9. Factors affecting blood pressure:
1. Cardiac output (CO= SV X PR)
2. Circulating blood volume (mainly affects systolic BP)
3. Elasticity of vessel wall
4. Viscosity of blood

10. Hypertension: (JNC 8)
• Average 2 or more readings are taken in each of 2 or more visits.
• Pre-hypertensive: risk of progression to hypertension is high.
• Hypertensive urgency: > 180/100 mm hg without target organ damage.
• Hypertensive emergency: > 180/100mm Hg with target organ damage.
• Malignant hypertension: > 200/130 with grade III or IV retinal
damage.

11. Grading of
hypertension:
STAGES SBP(MM
HG)
DBP(MM HG)
Normal <120 <80
Pre-hypertension 120-139 80-89
Stage 1
hypertension
140-159 90-99
Stage 2
hypertension
> 160 > 100

12. Etiology:
• Primary:
1. Environmental (multiple genes, DM, obesity and heart disease)
2. Genetic (DNA methylation is implicated in stress hypertension and pre-ecalmpsic hypertension)
• Secondary:
1. Renal: parenchymal and renovascular
2. Vascular: COA, Collagen vascular diseases
3. Endocrine: Conn’s syndrome, Cushing syndrome, pheochromocytoma, CAH, hyperthyroidism
4. Neurogenic: Tumor, ICT, GBS
5. Drugs: Ethanol, NSAIDS
6. Miscellaneous: PIH, OSA

13. Nonpharmacological therapies:
• Weight loss
• Stop alcoholism and smoking
• Reduce sodium intake
• Aerobic exercise
• Adequate intake of potassium, calcium and magnesium
• Reduce intake of saturated fat and cholesterol.

14. Lifestyle changes:
• Smoking Cessation
• Control blood glucose and lipids
• Diet Eat healthy (i.e., DASH diet)
• Moderate alcohol consumption
• Reduce sodium intake to no more than 2,400 mg/day
• Physical activity: Moderate-to-vigorous activity 3-4 days a week averaging
40 min per session.

15. Recommendation 1:
In age group > 60years:
1. Start drug treatment if BP > 150/90 mm Hg
2. Treatment goal of is < 150/90 mm Hg.

16. Recommendation 2:
In the general population <60 years:
1. Initiate pharmacologic treatment to lower BP at DBP > 90mmHg
2. Treatment goal DBP <90mmHg.

17. Recommendation 3:
In the general population <60 years:
1. Initiate pharmacologic treatment to lower BP at SBP>140mmHg
2. Treatment goal SBP <140mmHg.

18. Recommendation 4:
In the population aged >18 years with CKD:
1. Initiate treatment: SBP>140mm Hg and DBP>90mm Hg.
2. Treatment goal: SBP<140mmHg and DBP<90mmHg.

19. Recommendation 5:
In the population aged>18years with diabetes:
1. Initiate treatment: SBP>140mm Hg and DBP>90mm Hg.
2. Treatment goal: SBP<140mmHg and DBP<90mmHg.

20. Recommendation 6:
NON-BLACK – FIRST LINE :
In nonblack individuals including patients with diabetes, initial
antihypertensives recommended are:
1. Thiazide diuretics
2. Calcium channel blockers(CCB)
3. Angiotensin converting enzyme inhibitors(ACEI)
4. Angiotensin receptor blocker(ARB)

21. Recommendation 7:
BLACK – FIRST LINE :
In nonblack individuals including patients with diabetes, initial
antihypertensives recommended are:
1. Thiazide diuretics
2. Calcium channel blockers(CCB)

22. Recommendation 8:
CKD- FIRST LINE/ADD-ON:
In adults aged >18years with chronic kidney disease and hypertension,
preferred agents are ACEIs or ARBs.

23. Recommendation 9:
• Don’t combine ACEI and ARB.
• If BP goal is not reached within one month of treatment, increase the dose
of the drug or add 2nd drug. If not reached with 2 drugs, add and titrate a
third drug.
• If goal cannot be reached using only the drugs from class of thiazide, CCB,
ACEI or ARB, or there is any contraindication, or need of use of more than
3 drugs to reach goal, antihypertensives of other classes to be added.

24. Strategies to dose antihypertensives:
A. Start one drug, titrate to maximum dose, and then add a second drug.
B. Start one drug and then add a second drug before achieving maximum
dose of the initial drug.
C. Begin with 2 drugs at the same time, either as 2 separate pills or as a
single pill combination : when SBP>160mmHg and DBP: > 100mmHg or
if SBP is >20 mm Hg above goal and/or DBP is >10 mm Hg above goal.

25. Indications:
• HF: Beta blockers, ACEI, ARB, (CCB less indicated)
• Post MI: Beta blocker, ACEI, ARB.
• CAD risk: Beta blocker, ACEI, CCB
• DM: ACEI, ARB, CCB (BB less indicated)
• CKD: ACEI, ARB, CCB(BB less indicated)
• Recurrent stroke prevention: ACEI, Diuretics(BB less indicated)

26. Summary :
This Photo by Unknown Author is licensed under CC BY-NC-ND

27. Thank You..