1. PULMONARY FUNCTION TESTS
Effort dependent tests
- Forced expiratory volumes/flow rates
Effort independent tests
- Relaxed vital capacity
- Helium static lung volume
Gas diffusion tests
- CO transfer factor
- Arterial blood gases (resting)
- SaO2 during exercise

2. DYNAMIC LUNG VOLUMES (SPIROMETRY)
Volume (L) vs Time (s) curve
- Forced expiratory manoeuvre: from TLC to RV
Forced expiratory volume in 1 s : FEV1 (L)
Forced vital capacity : FVC (L)
Forced expiratory ratio : FER (FEV1/FVC%)

4. EXPIRATORY FLOW RATES
Flow -volume curve: dv/dt (flow-rate) from volume time curve
- Flow rate (L/s) plotted against forced expiratory volume (L) - from TLC to RV

5. EXPIRATORY FLOW RATES Shape of expiratory flow-volume curve:
Volume dependent expiratory airway closure
- asthma, chronic bronchitis
Pressure dependent expiratory airway closure
- emphysema

7. EXPIRATORY FLOW RATES From flow-volume curve:
Peak expiratory flow rate (PEFR)
- expressed in L/min (L/s x 60)
- also measurable with simple linear peak flow meter
Forced expiratory flow rate (FEFR) at a % of FVC
- FEFR 50%, FEFR 75%

8. Obstructive Restrictive
PEFR  Normal
FEV1   
FVC Normal(Asthma) 
(COPD)
FEV1/FVC ratio < 75% > 75%
FEV1 response > 15% (Asthma)
to 2-agonist <15% (COPD) No response

9. BRONCHIAL CHALLENGE TESTING
Exercise
Methacholine/Histamine
- marker of airway hyperreactivity
- concentration to produce 20%  FEV1
Allergens/Chemicals
- early and late responses
- diagnosis of occupational asthma

11. EXERCISE TESTING FEV1 or PEF post exercise - Asthma
SaO2 during exercise in interstitial lung disease
- to monitor treatment response
Differentiate cardiac vs respiratory dyspnoea
- heart rate vs oxygen uptake vs ventilatory rate

12. STATIC LUNG VOLUMES Effort independent test
Helium dilution / N2 washout : functional residual capacity
(RV = FRC - ERV) (TLC = VC + RV)
TLC in hyperinflation (Emphysema)
TLC in restrictive lung disease
Gas trapping in COPD:
(RV/TLC%) (RVC - FVC/RVC%)
TLC adds little to RVC and FVC

15. TRANSFER FACTOR (DIFFUSION CAPACITY)
CO diffusion across alveolar-capillary barrier
TLCO - total lung transfer for CO
TLCO: Anaemia, Emphysema, Int lung disease, Pulmonary oedema, Pulmonary emboli
To monitor treatment response in In lung disease

16. SUMMARY OF LUNG FUNCTION PATTERNS
Parameter Obstructive Restrictive
PEFR  Normal
FEV1  
FVC Normal in asthma 
Reduced in COPD
FEV1/FVC% <75% >75%
Gas transfer (TLCO)  in Emphysema
Normal in Asthma
FEV1 response to
 2-agonist > 15% in asthma No response
< 15% in COPD 