The document discusses concepts related to respiratory and cardiovascular medicine. It covers topics such as the respiratory system including ventilation, gas exchange, gas transport, and cellular respiration. It also discusses the cardiovascular system including heart anatomy, the conducting system, the cardiac cycle, vascular system, blood pressure, and circulation to different organs. Key diseases of the respiratory and cardiovascular systems are also summarized.

1. Term 4

2. The Scope of the Discussion
 Concepts of Respiratory medicine
 Concepts of Cardiovascular medicine
 Chest X-ray for Cardiovascular & Respiratory purposes

3. Cells need O2
 Why?
Because cells need energy
Therefore they need to produce ATP
To produce ATP, cells need O2
 Why ATP?
It’s the universal energy source
 What does that mean?
Every cell can use ATP for their energy needs

4. Cells need O2
 How do we produce ATP from O2?
Electron Transport Chain
In the inner mitochondrial membrane
 Does that mean cells that don’t have mitochondria can not
produce ATP?
Yes, they can’t
 What are the examples? mature human RBC
 How do they survive?
They rely on ATP produced by other cells
 How do they get ATP from other cells?
Via blood

5. Bottom line is,
 Almost all the cells need O2
 There should be a way to get O2 from the environment & deliver it to
each & every single cell in the body.
(It’s like ordering a pizza & getting it delivered to your
doorstep)
 Human body basically needs 2 major things to complete this
process
Respiratory system & Cardiovascular system

6. Respiratory
System

7. Process of Respiration
Ventilation
Gas
exchange
Gas
Transport
Cellular
Respiration

8. Ventilation
 Expansion of thoracic cavity (Diaphragm/IC muscles)
 What is Pleura & Pleural cavity
 Boyles Law acting inside it
 Bulk flow gases
 Inspiration (Active) & Expiration (Passive*)
 What is ventilatory failure? (not respiratory failure)
 Air way restriction, Fibrosis & Paralysis can compromise process
of ventilation

9. Gas Exchange
 Before going there we need to recap some basic kinetic physics
 Is there a pressure inside a vacuum. NO. Why?
 Because there are no molecules to create a pressure. NO molecules to
collide & therefore no pressure created.
 Now let’s think about air.
 Air is a mixture of gases. (N2/O2/CO2 & other)
 Total pressure of air = Sum of pressures created by individual gas
 Pressures created by individual gas is called “Partial pressure of that gas”
 In other words, the particular gas’s contribution to the total pressure.
 SO why are we concerned about these individual pressures rather than
the total pressure?
 Because pressure created by some people matters to us rather than
pressure created by others even though how great that the magnitude is.
(Pressure created by girlfriend vs pressure created by lecturers)

10. Gas Exchange
 Partial pressure of O2 & partial pressure of CO2 are way more
important to human bodies & therefore to us, medical
students & doctors who are trying to figure out what’s
happening inside.
 PaO2 is to indicate partial pressure of Oxygen
 PaCO2 is to indicate partial pressure of CO2

11. Gas Exchange
 Alveolar Capillary Membrane
 Diffusion capacity of gases
 A-A Gradient
 Diseases affecting gas exchange
- IRDS & ARDS
- Pulmonary oedema* (Heart failure, Pneumonia)
-
* J cells

12. Gas Exchange
 Pulmonary & Systemic circulation
Sup. & Inf.
Vena cava
Right
atrium
Tricuspid
valve
Right
Ventricle
Pulmonary
Arteries
Pulmonary
Capillaries
Pulmonary
Veins
Left Atrium Mitral Valve
Left
Ventricle
Aorta
Systemic
Circulation

13. Ventilation & Perfusion
 Has to be complimentary (or Matched) – Why?
 Normal variation in lung
 Concept of Shunt & Dead Space
 Speaking of Dead Space….What do you understand by
dead space?
 Back to those concepts
 Cyanosis
 Diseases causing V/Q mismatch

14. In Blood?
 “PaO2” ……?
 O2 saturation…..?
 Hb-O2 Curve
 Meaning of right & left shift
 Stories (fever/HARA)
 Cyanosis again
 Cellular respiration & CN poisoning

15. Regulation
 Mainly Neural
 Altered by PaO2, [H+] & PaCO2
 How?
 Central & Peripheral chemo receptors?
 E.g. – Exercise/ High altitudes/ Metabolic
 Neurological failure
 Sleep Apnoea?

16. Respiratory Adjustments
 Exercise
 High altitudes
 Metabolic (Acidosis/Alkalosis)
- DM
- CRF
-

17. Respiratory Diseases
 Infections (Respiratory tract & Lung)
 Obstructive diseases
 Restrictive diseases (more correctly Interstitial lung diseases)
 Pulmonary vascular diseases
 Tumors of the Lung & Bronchus
 Diseases of Pleura, Diaphragm & Chest Wall
 Respiratory failure…..???

18. Respiratory Failure
Respiratory
failure
Type 1
Diffusion
Problems
Type 2
Ventilatory
Problems

19. Any Questions…?

20. Topics we have covered
Process of Respiration
Regulation of Respiration
Respiratory adjustments
Respiratory diseases
NOTE: Always get used to look back & summarize what’s been
said, discussed or learned.

21. Cardiovascular
System

22. Topics
 Heart
- Anatomy (Gross/Histologic)
- Conducting system
- Cardiac cycle
 Vascular system
- Blood pressure
- Circulation in heart/brain/skin/GI tract
- Renal circulation

23. Recap - Anatomy
Gross – 4 chambers/4 valves/3 layers/ 2 vessels
Murmurs & other effects of valvular lesions
Coronary circulation
MI/IHD
Histology – 2 types of cells
1. Cardiac myocytes (functionally similar)
2. Specialized myocytes (lack contractile properties/ different action potentials ć
long RF period)

24. Conducting System
SA node
3 inter-
nodal
pathways
AV node
Bundle of
His
L & R
bundle
branches
Purkinje
system

25. Conducting System
 Made up of specialized myocytes
 Capable of spontaneous discharge
 At different rates
e.g.:- SA node 70, AV node 40, PK sys 20
Conducting
System
Vagus nerve
(-)
Baroreceptors
Circulating
catecholamin
es
(+)
Adrenal
cortex

26. Arrhythmias
Arrhythmias
Brady
< 60 bpm
Sinus
bradycardia
Heart Blocks
Tachy
> 100 bpm
Sinus
tachycardia
Supraventricular
tachycardias
Ventricular
tachycardia

27. Sinus Bradycardia
Sinus bradycardia
Physiological
(Normal)
Sleeping
Athletes
β - Blockers
Pathological
(Abnormal)
Sick sinus syndrome
Jaundice
Myxoedema
Hypothermia

28. Heart Blocks
Heart blocks
1st Degree
2nd Degree
Morbitz
type 1
Morbitz
type 2
3rd Degree
(Complete)
• Causes…?

29. Sinus Tachycardia
Sinus Tachycardia
Physiological
(Normal)
Exercise
Anxiety
Pathological
(Abnormal)
Anaemia
Fever (Hyperthermia)
Thyrotoxicosis
Hypothermia

30. Tachycardia
Tachycardia
Supraventricular*
Atrial Flutter
Atrial Fibrillation*
Ventricular
Ventricular Tachycardia
Ventricular Fibrillation*

31. Arrhythmias
 Two main problems in arrhythmias
1. ↓ Cardiac output
2. Stasis of blood (Thomboembolisms)
Mx
Bradycardias
Pace-makers
Rx of cause
Tachycardias
β Blockers
Defibrillator

32. ECG

33. Therapeutic Procedures
 Cardiac catheterization & stenting
 Valve replacement
 CABG
 Transesophageal sonography
 Pacemakers
 Radiofrequency ablation
 DC cardioversion (Defibrillation)