Figures
- FIGURE 1
Idiopathic and non-idiopathic interstitial lung disease (ILD). IIP: idiopathic interstitial pneumonia; CTD: connective tissue disease; IPAF: interstitial pneumonia with autoimmune features; LIP: lymphocytic interstitial pneumonia; PPFE: pleuroparenchymal fibroelastosis; COP: cryptogenic organising pneumonia; AIP: acute interstitial pneumonitis; IPF: idiopathic pulmonary fibrosis; NSIP: nonspecific interstitial pneumonia; RB: respiratory bronchiolitis; DIP: desquamative interstitial pneumonia.
Tables
- TABLE 1
Factors associated with increased risk of mortality in idiopathic pulmonary fibrosis
At baseline Level of dyspnoea DLCO <40% predicted Desaturation <88% during 6MWT Peak V′O2 <8.3 mL·kg−1·min−1 on CPET Extent of honeycombing on HRCT Pulmonary hypertension Longitudinal factors Increase in level of dyspnoea FVC <10% of absolute value DLCO <15% of absolute value Worsening of fibrosis on HRCT Information from [9, 12]. DLCO: diffusion capacity of the lung for carbon monoxide; 6MWT: 6-min walk test; V′O2: oxygen uptake; CPET: cardiopulmonary exercise test; HRCT: high-resolution computed tomography; FVC: forced vital capacity.
- TABLE 2
Common cardiopulmonary exercise test features at peak exercise in interstitial lung disease (ILD) patients compared to healthy subjects
Healthy subjects ILD patients Cause Peak V′O2 L·min−1 ≥85% <85% Hypoxia, ventilatory limitation, deconditioning Maximum work W ≥85% <85% Hypoxia, ventilatory limitation, deconditioning Heart rate beats·min−1 ≥85% <85% Ventilator limitation to exercise, deconditioning Oxygen saturation Preserved Reduced Increased V/Q mismatch, diffusion limitation, shunt, reduced mixed venous oxygen concentration Respiratory frequency breaths·min−1 <50 >50 Respiratory muscle elastic loading, stimulation of peripheral mechanoreceptors VT L Increased Reduced Reduced lung compliance V′E L·min−1 50–80% of MVV >90% of MVV Ventilator limitation to exercise VD/VT Reduced Unchanged or increased Increased V/Q mismatch, rapid, shallow breathing pattern V′E/V′CO2 slope 25–35 >35 Increased V/Q mismatch Anaerobic threshold L·min−1 >45% peak V′O2 <45% peak V′O2 Hypoxia, pulmonary hypertension Data are presented as n, unless otherwise stated. V′O2: oxygen uptake; VT: tidal volume; V′E: minute ventilation; VD: dead space volume; V′CO2: carbon dioxide production; MVV: maximal voluntary ventilation; V/Q: ventilation/perfusion.
