This presentation speaks about hypertension and how the brain regulates blood pressure. It also describes the ill effects of increased blood pressure on the human body. The intention of this presentation is to create an awareness on how lifestyle changes can help in managing blood pressure

1. Srikanth KS
An IT Professional

2. Disclaimer
This slide show should only be used to understand the
way our human body regulates blood pressure.
This does not replace or substitute and analysis done
by a qualified medical professional
All suggestions regarding lifestyle changes can be done
after taking advice from your doctor
The intension of this presentation is only to explain
the concept of hypertension in plain English

3. What is blood pressure
The pressure of the blood in the circulatory system.
Blood pressure is represented as two parameters
Systolic blood pressure and Diastolic blood pressure
A normal average blood pressure in a human being is
120/80 mm Hg
Or 120 mm Mercury Systolic pressure and 80mm
Mercury of diastolic blood pressure

4. What factors affect the Blood
pressure
Blood pressure is composed of two parts the Systolic and
diastolic.
The Systolic pressure is dependent on the Cardiac Output
Cardiac output total volume blood in 1 minute
The Diastolic pressure is dependent on the total peripheral
resistance
Lets try to understand the same with the help of a simple
picture
Mean arterial pressure : Average arterial pressure during a
single cardiac cycle
MAP = f(Cardiac output, TPR, Blood volume)

5. A sketch of the heart
The Systolic pressure is dependent on the Cardiac Output.
Cardiac output is defined as the volume of blood pumped into the
aorta when the ventricles contract

6. Total Peripheral resistance
The diastolic pressures is dependent on the total peripheral
resistance.
This parameter directly influences the prefill of the atria
* Drawings hand drawn using MS paint

7. A graphical representation

8. How does the Systolic or diastolic
pressure increase?
As we know systolic pressures is dependent on the
cardiac output higher the heart rate higher the systolic
pressure
Heart rate can increase when we run, we are afraid,
under stress etc
Higher the total peripheral resistance, higher the
diastolic pressure
This can happen when the capillaries constrict

9. Blood pressure Regulation
Short term regulation of blood pressure.
Normally when a person runs the blood pressure tends
to increase. The brain immediately takes control and
provides a feedback to control the pressures within
normal limits
Long term regulation of Blood Pressure
Managed using Renin Angiotensin Aldosterone
System (RAAS)

10. Short term blood pressure
regulation

11. What are Para sympathetic nerves ?

12. Short term regulation Summary
Baro receptors are taking information from Carotid sinus
through the 9th Cranial nerve (Glossopharyngeal nerve) Sensitive
to both High and Low BP
Baro receptors are taking information from the aorta to the 10th
cranial nerve called Vagus nerve sensitive only to High BP
If the BP goes up the nerves are more stretched more action
potential is sent to the Tractus Solitarius
TS will activate the Cardio inhibitory centre. It goes to the SA
node and AV node to reduce the heart rate. And inhibits the
cardio accelerator. These two will decrease the cardiac output.
Vaso motor centre is also inhibited which in-turn produces
vein/artery dilation[Epinephrin induced] (Para sympathetic
nervous system)

13. Long term blood pressure
regulation - RAAS
Renin + Angiotensinogen = Angiotensin I
Angiotensin I –> Angiotensin II
Angiotensinogen
Renin

14. Long term regulation
Juxtaglomerular apparatus

15. Significance of ACE
Alvioli
Pulmonary Vein
Pulmonary Artery
Angiotensin I Angiotensin II

16. Summary of RAAS
When blood pressure is dropped, we have reduced renal
perfusion.
Polkesin cells have Baro receptors and Macula Densa are
sensitive to Sodium
Baro receptors are less stretched. Macula Densa are
reporting lesser Sodium concentration
This triggers release of Renin.
Liver secretes Angiotensinogen Co-enzyme which is
converted to Angiotensin I by reacting with Renin
Angiotensin I (Deca peptide) reacts with Angiotensin
converting enzyme present In the arteries lining the lungs
to Angiotensin II (Octa peptide)

17. Summary of RAAS
Angiotensin II can act as a vaso constrictor because of
a release of calcium release in the endoplasmic
reticulum causing constriction
Also Angiotensin II will increase the thirst in the
person. Increase of water will increase the diastolic
volume
All sympathetic nerves have Angiotensin II receptors
releasing more Nor-epinephirin
Which increases the cardiac output

18. Aldosterone contribution
It acts as a sodium and potassium pump and absorbs
more sodium to the blood stream and discards more
potassium through urine
Principle cells lose more sodium in this process. This
forces the principle cells to absorb the sodium that
would have normally been lost by urine
Further it increases the urea in the blood
This process takes normally a few days thereby
modifying the principle cells

19. Management of Blood pressureBlood pressure treatment goals*
*Although 120/80 mm Hg or lower is the ideal blood pressure goal, doctors are unsure if
you need treatment (medications) to reach that level.
Less than 150/90 mm Hg If you're a healthy adult age 60 or older
Less than 140/90 mm Hg If you're a healthy adult younger than age
60
Less than 140/90 mm Hg If you have chronic kidney disease,
diabetes or coronary artery disease or are at
high risk of coronary artery disease

20. Drugs that can reduce high Blood
pressure
Thiazide diuretics Lasix: Water Pill
Beta blockers (Atenelol): Reduces heart rate there
by reducing the cardiac output
Angiotensin-converting enzyme (ACE) inhibitors
(Captopril)
Angiotensin II receptor blockers (ARBs)
(Lozartran potassium)
Calcium channel blockers (Amlodopine) Reduces
entry of calcium into the blood there by redicing
blood pressure

21. Simpler solution to reduce blood
pressure
Lifestyle changes
Below are some changes you could make to your lifestyle to
reduce high blood pressure. Some of these will lower your
blood pressure in a matter of weeks, others may take longer.
Cut your salt intake to less than 6g (0.2oz) a day.
Eat a healthy, low-fat, balanced diet, including plenty of
fresh fruit and vegetables.
Be active: being physically active is one of the most
important things you can do to prevent or control high
blood pressure.
Cut down on alcohol.
Lose weight.
Stop smoking. Smoking greatly increases your chances of
getting heart and lung diseases.
Drink less coffee, tea or other caffeine-rich drinks such
as cola. Drinking more than four cups of coffee a day may
increase your blood pressure.

22. Risks involved for hypertensive
patients
Excess body weight
More stress
Reduced oxygen supply to the organs
Increased sodium concentration in the blood
Increased bicarbonates in the blood
Lethargy
Fatigue
Kidney problems
Breathing difficulties

23. Our Human Heart

24. Reference
Physiology of the heart – 5th edition
Dr Najeeb lectures on blood pressure regulation
Dr Biswaroop Roy Chowdry – Diabetics Type I and II
management through lifestyle changes

25. About the author
Srikanth KS completed his MS from BITS Pilani
specialized in software systems. He works in a multi
national company as a software engineer responsible for
design and development of embedded software.
He has been in this industry since 15 years.
He has a passion towards medical science and has put
efforts in understanding the physiology of the heart with.
He again stresses the fact that this presentation is only to
understand the concept better. You are advised to speak to
your doctor or physical instruction trainers before starting
or stopping an exercise
All his posts can be found at
http://www.slideshare.net/SrikanthKS2
The Author thanks Hari KA for providing a platform
http://www.primedin.in/ which can be used for
presenting online lectures