Ch 5 - The Cardiovascular System

Question 1

What makes up the circulatory system

Answer 1

The heart

Blood vessels:
The arteries
The Veins
The capillaries

Question 2

Blood transports:

Answer 2

Carbon dioxide 
Oxygen
Glucose and other Nutrients 
Hormones 
White blood cells
Haemoglobin
Platelets 
Plasma

Question 3

What blood vessels do when experiencing cold conditions and warm conditions

Answer 3

Vasoconstriction - The vessels constrict and move inwards towards the warmth

Vasodilation - Move outwards towards the skin and dilate to lose heat

Question 4

Circulatory Systems

Answer 4

Pulmonary:
Heart to the lungs (de-o2) and then to the heart (o2)

Systemic:
Heart (o2) to the body where exchange happens at the cells, then back to the heart (de-o2)

Question 5

Arteries

Answer 5

Carry o2
Red in diagrams (usually)
Move blood away from the heart
Work under much higher pressure than the veins

Question 6

Veins

Answer 6

Transport de-o2 blood
Usually blue in diagrams
Carries de-o2 blood to the heart
Have valves in them to prevent back flow

Question 7

Capillaries

Answer 7

1 cell thick

Permeable for gas exchange (Ficks Law of Diffusion)

Question 8

How the Blood vessels interact

Answer 8

Arteries (transport o2) -> Capillaries (gas exchange occurs) -> Veins (carry de-o2 blood back to the heart)

Question 9

Composition of Blood - RBC

Answer 9

Red Blood Cells

Produced in the bone marrow
Transport:
Haemoglobin 
- Body decides how much it needs (people and height and athletes have a higher amount usually)
- Also made in bone marrow 
- A type of protein 
- Replaced every 108 - 140 Days

Question 10

The Composition of Blood - WBC

Answer 10

White Blood Cells
- Made in bone marrow

• Fight infections/bacterias (part of the immune system)

Question 11

Composition of Blood - Plasma

Answer 11

A salty liquid in our blood that has no cells in it

- Where you would find the carbonic acid mix

Question 12

Composition of Blood - Platelets

Answer 12

Responsible for the coagulation of our blood (clump our blood together)

• Forms blood clots
• Rush to the surface when we cut ourselves to form a scab

Question 13

Blood Flow Through The Heart

Answer 13

All De-Oxygenated:
1 - Vena Cava
2 - Right Atrium - Stores blood (weak pump)
3 - Right Ventricle - Main pumping force (strong thick muscle)
4 - Pulmonary Arteries (only arteries to carry de-o2)
5 - Lungs (where the blood exchanges CO2 for O2 and becomes oxygenated)

All Oxygenated:
1 - Pulmonary Veins (transport newly o2ated blood to heart -Only veins to carry 02ated blood)
2 - Left Atrium (storage)
3 - Left Ventricle - Major pump
4 - Aorta 
5 - Systemic System

Question 14

Blood Supply to the Heart

Answer 14

The heart is a big muscle and requires fuel (o2 and glucose) through internal respiration

Wrapped in its own arteries and veins

• Coronary artery delivers o2 and nutrients
• Coronary Veins remove waste products:
  - Carbon dioxide
  - Water (Which forms carbonic acid)

Question 15

Pulse Rate

Answer 15

Average of 72bpm in an average healthy adult

Controlled by: (autonomous NS / Vegetative)

• Glucose levels
• Exercise
• Adrenaline
• CO2

Effected by: - Eating

• Caffeine / drugs
• Age (pulse increases as you get older)
• Gender (females have a slightly higher pulse)

Question 16

Stroke Volume

Answer 16

The amount of blood pumped by the left ventricle in 1 contraction

• Roughly 70ml on average

Question 17

Cardiac Output

Answer 17

The volume of blood pumped by the heart in 1 minutes

CO = HR x SV

Average is roughly 5-5.5 Litres per minute

Question 18

Coronary Heart Disease

Answer 18

Coronary arteries block over time - Plaque builds up
- The heart then no longer can function properly as it doesn’t receive the nutrients and energy it needs

• Clots can form and also block the arteries and veins

When veins block, the waste products can no longer be removed :
- Leads to pain in the heart (angina)

Question 19

Factors that can increase the risk of Angina

Answer 19

Age
Stress
CHD

Question 20

Heart Attack (Myocardial Infarction)

Answer 20

CHD can lead to a heart attack (where an area of the heart receives such little o2, it actually dies)

Question 21

Symptoms of a Heart Attack

Answer 21

Pain in the left side of the body and heart
Breathing rate increases
Chest becomes tight 
Feelings of Nausea - Vomiting 
Sweating
Pallor 

80% of victims admitted to hospital survive

Most common cause of deaths to males over 40

Question 22

Factors making you most prone to a myocardial infarction

Answer 22

Hereditary (most contributing factor)
Smoking
High blood pressure (hypertension)
Lack of exercise (20/30 mins 3x a week)
Diabetes (bought upon by obesity)

Question 23

Anaemia

Answer 23

A low red blood cell count leading to:

• Decreased amounts of haemoglobin
• Decreased amounts of iron (found in broccoli, chocolate, red meat, wheetabix)

Symptoms:

• Pallor (pale)
• Lethargic (tired, weak, fatigue)

Question 24

Carbon Monoxide Poisoning

Answer 24

Caused by the incomplete combustion of carbon
(Piston engine aircraft more likely than jets)

CO is more easily absorbed into haemoglobin than o2 (210-250% more easily than o2)

Body does not react to it and doesn’t know it is happening

• Odourless
• Colourless (cant detect it)

Highly toxic and will kill you

Question 25

Symptoms of Cardbon Monoxide poisoning (CO)

Answer 25

``` Headache Quite red (flushed - cherry red skin (RUDDY)) Dizziness and impaired vision Nausea Lethargic (sleepy and weak) Joint Pain Impaired memory Unconsciousness -> Death ``` Can be caused by cockpit heaters but there are detectors

Question 26

If carbon monoxide is present in the cabin and factors that affect the severity

Answer 26

Put on o2 mask and breath 100% Turn off cabin heater In light aircraft you can open the windows or Verny Land ASAP Can be several days recovery - See you AME Factors affecting the severity: - Altitude - Smoking - Lung disease or infection - Age - Obesity

Question 27

Smoking

Answer 27

Cigarettes contain: - Carbon monoxide - reduce the amount of saturated O2 - Nicotine - Tar (substance used to tar roads) - Arsenic and Cyanide (Highly Poisonous) Affect: - Time of useful consciousness is reduced by 50% in the case of hypoxia - Night vision decreases - Reduced G tolerance - Increase the risk of CHD and heart attacks - Carboxyhemoglobin levels increase by 7% if smoking 20 a day

Question 28

Blood Pressure

Answer 28

Depends on: - HR (xSV=CO) - Elasticity of arterial walls and thickness - Peripheral resistance (plaque) - Viscosity of the blood - Age plays a big part. BP increases as you get older as arterial walls thicken and elasticity decreases Systolic/Diastolic (mmHg)

Question 29

Systolic Pressure

Answer 29

When the ventricles contract. Is the pressure in the arteries as the ventricles contract. Measured on the upper arm as the blood pressure is going to be roughy the same as the heart as it is on the same level of the heart.

Question 30

Diastolic Pressure

Answer 30

When the ventricles are relaxed, in between beats

Question 31

Hypertension definition causes and effects

Answer 31

High BP. 140/90mmHg ``` Causes: Age Obesity Stress Hereditary Gender Pregnancy Smoking ``` ``` Effects: Can lead to strokes Heart attack Angina Nose bleeds Heart palpitations Complete kidney failure (stagnation of waste products -> toxins) ```

Question 32

Treating Hypertension

Answer 32

``` Decrease amount of salt in the diet (decrease cholesterol) Exercise Reduce stress Drugs (thin the blood) Stop smoking ```

Question 33

Hypotension causes and effect

Answer 33

Low blood pressure ``` Causes: Haemorrhage - accidents /disease Low glucose levels Giving blood - bad response which is emotional (shock) Emotions Genetics / Hereditary ``` ``` Effects: Death Pallor and clammy Dizziness -> pass out Nausea Reduced concentration levels Stagnation of blood (pooling in the lower extremities which can lead to death of areas in contact with) Lethargy ```

Question 34

Treatment of Hypotension

Answer 34

Clog bleeding asap Drugs to increases platelet count Eat surgery items

Question 35

Pressoreceptors

Answer 35

Located in the carotid artery, up stream of the heart but before the brain They help regulate BP and Heart rate Part of the autonomous NS regulation. Hypertensive - pressorecptors decrease HR and atrial walls relax Hypotensive -> Increase HR and tighten arterial walls

Question 36

Blood Donation

Answer 36

The reaction to blood donation is emotional (shock) which leads to a decrease BP and then fainting (syncope) Increased susceptibility to hypoxia due to the decreased levels of haemoglobin (cant usually give blood within 3/4 months) - Shouldn't give blood 24 hours before duty If you give blood, you can reduce the effects: - Drink plenty of fluids - Lying flat (supine) for 15 - 30 minutes - Seek advice from AME before you do it