Blood Pressure

Question 1

What is the vasculature?

Answer 1

Network of blood vessels connecting heart with all other organs and tissues in body

Question 2

What do arteries and aterioles do?

Answer 2

Bring oxygen rich blood and nutrients from heart to organs and tissues

Question 3

What do veins and venules do?

Answer 3

Carry deoxygenated blood back to the heart

Question 4

What takes place in the capillaries?

Answer 4

The exchange of gases and transfer of nutrient between blood and tissue

Question 5

What forms the cardiovascular system?

Answer 5

The heart and vasculature

Question 6

Arteries

Answer 6

Transport high-pressure blood from heart to smaller arteries and aterioles

Question 7

Aterioles

Answer 7

Connect arteries and capillaries

Question 8

Veins

Answer 8

Act as reservoir of blood and transport low pressure blood from venules to heart

Question 9

Venules

Answer 9

Connect capillaries and veins

Question 10

Capillaries

Answer 10

Allow gas exchange, nutrient transfer and waste removal between blood and tissue fluid

Question 11

Structure of blood vessels - tunica interna

Answer 11

Smooth single layer of cells called the epithelium in direct contact with the blood. Cells easily damages by hypertension or toxins eg cigarette smoke

Question 12

Structure of blood vessels - tunica media

Answer 12

Middle layer comprising of smooth muscle and elastin, under influence of sympathetic nervous system and can initiate vasoconstriction and vasodilation

Question 13

Structure of blood vessels - Tunica externa

Answer 13

Outer layer comprising connective tissue fibres that protect the blood vessels and secure them to surrounding tissues

Question 14

Arterial system

Answer 14

Arteries supply body with with oxygenated blood
2 exceptions:
Pulmonary arteries from heart carry deoxygenated blood to lungs
Umbilical artery carries deoxygenated blood from fetus to placenta
Aorta = largest artery, leaving left ventricle and extends down left side

Question 15

Venous system

Answer 15

Veins thin elastic vessels act as reservoir of blood, large lumen and valves to ensure one way blood flow

Superior and inferior venae cavae = largest veins

Question 16

BP is influenced by…

Answer 16

Total volume of blood in body
Cardiac output - amount of blood pumped in 1 min
PVR peripheral vascular resistance to flow of blood in arterial system, influenced by vessel length, lumen diameter, blood viscosity
BP can be affected by change in cardiac output or PVR

Question 17

What is blood pressure?

Answer 17

Pressure of blood against the walls of main arteries

Question 18

Systolic blood pressure

Answer 18

Peak blood pressure in the artery following ventricular systole (contraction)

Question 19

Diastolic blood pressure

Answer 19

Level to which BP falls during ventricular diastole (relaxation)

Question 20

Hypertension

Answer 20

If consistently over 140/90mmHg

Question 21

Hypotension

Answer 21

Systolic reading of less than 90

Question 22

Factors causing variation in BP

Answer 22

Emotional state 
Temperature 
Respiration 
Bladder distension 
Pain 
Exercise 
Race/ethnicity 
Tabacco use 
Diurnal variation 
Alcohol use 
White coat hypertension 
Sudden change in posture 
Underlying medical conditions

Question 23

Blood pressure, pregnancy and birth

Answer 23

Haemodynamic changes: increase blood volume, cardiac output, and blood viscosity
Hormonal changes: progesterone acts on smooth muscle
Impaired venous return - gravid uterus

Question 24

Procedure

Answer 24

I.C + discuss
Apply cuff over brachial artery
Sphygmomanometer at level with woman’s heart
Suitable position legs uncrosses
Expose arm and palpate brachial artery, position cuff 2-3cm above antecubital fossa
Palpate brachial artery with fingertips and pump rapidly with other until pulse disappears, continue to inflate 30 mmhg above this
Slowly deflate taking note when pulse reappeared - approx systolic
Place stethoscope, inflate to 20-30 above approx reading
Slowly deflate 2mmhg per second listening for Korotkoff 1 sound
Continue to deflate until korotkoff 5 sound
Remove cuff and assist woman into comfortable position
Clean stethoscope
Document and discuss, refer if nec

Question 25

Procedure - what factors may affect accuracy

Answer 25

Position of woman
Cuff position 
Rapid deflation 
Inappropriate cuff size 
Poorly maintained equipment