Pulmonary Function Tests (PFTs)

Obstructive vs Restrictive

Obstructive

• COPD

• Asthma

• Bronchiectasis (can also be mixed)

• Pulmonary haemorrhage- GPA, Goodpasture's

Restrictive

• Pulmonary fibrosis- idiopathic, asbestosis, silicosis

• Sarcoidosis 

• ABPA

• Pneumectomy 

• Extra pulmonary causes- obesity, MND

Transfer factor CO

• Low

  • ILD

  • COPD

• Normal

• Raised

  • Obesity

Respiratory Flow-Volume Loop

• Assess whether goitre is causing tracheal compression

Resources and References

Written in 2025