xxix List of abbreviations (C)HF (Congestive) heart failure AHI Apnoea–hypopnoea index AIDS Acquired immunodeficiency syndrome BMI Body mass index CF Cystic fibrosis COPD Chronic obstructive pulmonary disease CPAP Continuous positive airway pressure CT Computed tomography ECG Electrocardiogram ENT Ear, nose and throat FEV1 Forced expiratory volume in 1 s FVC Forced vital capacity Hb Haemoglobin HIV Human immunodeficiency virus HRCT High-resolution computed tomography KCO Transfer coefficient of the lung for carbon monoxide MRI Magnetic resonance imaging NIV Noninvasive ventilation OSA(S) Obstructive sleep apnoea (syndrome) PaCO2 Arterial carbon dioxide tension PaO2 Arterial oxygen tension PCR Polymerase chain reaction PtcCO2 Transcutaneous carbon dioxide tension SaO2 Arterial oxygen saturation SpO2 Arterial oxygen saturation measured by pulse oximetry TB Tuberculosis TLC Total lung capacity TLCO Transfer factor for the lung for carbon monoxide V'E Minute ventilation