Hypertension

Question 1

What is blood pressure? (BP)

Answer 1

Blood pressure is the force exerted by circulating blood on the walls of blood vessels.

Question 2

What is mean arterial blood pressure? (MAP)

Answer 2

average arterial pressure during a single cardiac cycle

Question 3

What are the two factors that affect BP?

Answer 3

1. Cardiac output (output from the heart/unit time. Calculated by SV x HR)
2. Stroke volume

Question 4

How do you calculate BP?

Answer 4

CO X PR = BP

Question 5

Factors that affect HR?

Answer 5

1. Hormones
2. Age
3. Autonomic innervation

Question 6

Factors that affect SV?

Answer 6

• contractility
• heart size
• preload
• duration of contraction
• total peripheral resistance

Question 7

What assists with venous blood flow back to the heart?

Answer 7

Pressure gradient

Question 8

Systolic?

Answer 8

maximum pressure at the peak of ventricular contraction

Question 9

Diastolic?

Answer 9

Minimum presssure at the end of ventricular contraction

Question 10

What are the 2 basic mechanisms for regulating BP?

Answer 10

1. Short term (neural) mechanisms
   
   • regulate blood vessel diameter, HR, and contractility
2. Long term (endocrine) mechanisms
   
   • regulate blood volume

Question 11

Factors that lead to decreased BP?

Answer 11

• decrease in peripheral resistance
• decrease of sympathetic activity
• decreased of aldosterone release
• increase of sodium and H20 secretion
• atrial natriuretic peptide release

Question 12

Factors that lead to increase BP?

Answer 12

• increase in peripheral resistance
• increase in sympathetic activity
• increase of aldosterone release
• decrease of sodium and H20 secretion

Question 13

Various sensors around the body monitor BP, and signal action potentials if the pressure increases or decreases. Name 6 of these.

Answer 13

1. Glossopharyngeal nerve
2. External carotid
3. Internal carotid
4. Carotid body chemoreceptors
5. vagus nerve
6. aortic body chemoreceptors

Question 14

Stimulation of peripheral chemoreceptors

Answer 14

• increased rate and depth of breathing
• increased cardiac output
• reduced arterial blood CO2 levels

Question 15

What BP is classified at hypertension?

Answer 15

Systolic >140

diastolic >90

Question 16

What is ventricular hypertrophy?

Answer 16

Abnormal enlargement of the ventricles of the heart. Caused by hypertension, heart muscle injury, or valvular disease. Occurs because of the increased work the heart muscle has to do to pump out the same quantity of bloody per minute against peripheral resistance.

Question 17

What is an echo used for?

Answer 17

Used to identify structure and function of the heart. Records measurement of heart dimensions such as

• End diastolic volume (EDV)
• Ejection fraction (EF)
• Stroke volume (SV)
• Fraction shortening (FS)

Question 18

Explain why BP could remain elevated after 6 months of taking anti-hypertensive medication?

Answer 18

• medication non-adherance
• life style factors e.g. diet, exercise, alcohol consumption, no physical activity
• secondary causes to hypertension
• severity of hypertension
• sub-optimal medication therapy

Question 19

What is Renal artery stenosis?

Answer 19

Narrowing of one, or both of the renal arteries which can impede the blood flow to the kidneys. Often caused by uncontrolled hypertension. Symptoms often include claudication.

Question 20

How to you diagnose renal artery stenosis? And what is the treatment?

Answer 20

Angiogram of lower limb blood vessels. Treatment is often a stent.