• DLCO is the most powerful predictor of survival in patients with COPD.
• DLCO is used as an indicator of lung disease severity.
• DLCO can show comorbidity of COPD in heart failure in patients.
• Assess the hospitalization risk in a COPD patient.
• DLCO is helpful in detecting drug-induced lung disease.
• DLCO is usedful as an early indicator for detecting interstitial lung disease before lung volumes become decreased.
• Monitor disease progression in CF patients with Lung Clearance Index(LCI)