An update on COPD guidelines ( GOLD Guide Lines) Most important symptom of COPD - breathlessness on exertion +/- productive or dry cough. Spirometry is necessary for early diagnosis because in early stage there are no symptoms. Suspect COPD in all patients with >10 pack year smoking history above age 40. Diagnosis is made on the basis of finding a fixed obstructive defect on spirometry along with a reduced gas transfer. A fixed obstructive defect is defined by a FEV1/FVC ratio of <0.7 or 70 % which does not normalize post bronchodilator.
This would mean that a person is unable to breathe out >70% of his forced vital capacity in 1 second. In normal adults the FEV1/FVC ratio is usually >0.8 or 80%. Normal Gas transfer or DLCO or diffusing capacity of carbon monoxide is usually >90% (when compared to standardized values for the lab and matched for age, sex and race). A reduced gas…
