1. TOTAL PULMONARY VENTILATION
Total pulmonary ventilation or Minute respiratory volume = Ventilation rate x Total volume =12 breaths/ mt x 500 ml/ breath =6000 ml / mt

2. Dead Spaces
Anatomic dead Space + Physiological dead space Alveolar dead space }

3. Rate of Alveolar Ventilation
=Ventilation rate x ( Tidal volume – dead space volume) = 12 x 500 – 150 = 12 x 350 = 4200 ml / mt

4. Effects of Breathing Pattern on Alveolar Ventilation
Fresh Air to Alveoli
Respiratory Rate Total Pulmonary (tidal volume – dead Alveolar Ventilation
Tidal Volume (ml) (Breaths / min ) Ventilation ( mL / min) space volume* ( mL / min)
500 (Normal) (Normal)
300(Shallow) ( rapid)
750 (Deep) ( Slow)

5. Types and Patterns of Ventilation
Eupnea Normal quiet breathing
Hyperpnea Increased respiratory rate and / or volume Exercise
in response to increased metabolism
Hyperventilation increased respiratory rate and / or volume Emotional hyperventilation;blowing up a without increased metabolism balloon
Hypoventilation Decreased alveolar ventilation Shallow breathing / asthma/ restrictive lung disease
Tachypnea Rapid breathing; usually increased Panting
respiratory rate with decreased depth
Dyspnea Difficulty in breathing (a subjective Various pathologies or hard exercise
feeling sometimes described as “ air
hunger”)
Apnea Cessation of breathing Voluntary breath-holding; depression of
CNS control centers

8. Ventilation-perfusion ratio

12. Respiratory Unit

13. Respiratory membrane

14. Physics of Diffusion

15. Concept of Partial Pressure

16. Gas Exchange at alveoli & Cell

19. Partial pressure of O2 (Po2) at various sites.
Po2 (mm Hg)
Atmospheric air (dry)
159
Inspired air ( partially wet)
158
Air entering lungs
149.3
Alveolar air
100
Arterialized blood in pulmonary veins entering left atrium 97
Arterial blood ( in aorta, arteries, arterioles ) 95
Tissue cells
40 or less
Mixed venous blood 40

20. Partial pressure of CO2 (PCo2) at various sites.
PCo2 (mm Hg)
Tissue cells
50 – 70
Venous Blood 46
Alveolar Air 40
Arterial Blood
Expired air 32