Investigations
Table 3: Investigations that should be performed in the ED when a patient is presenting with an exacerbation of COPD
| Arterial blood gas (ABG) analysis | To evaluate evidence of acidosis, hypercapnia, hypoxaemia and chronic metabolic compensation |
| CXR | To look for evidence of consolidation, exclude pneumothorax and exclude other pathologies which may cause increased breathlessness |
| ECG | To exclude other or concurrent causes of breathlessness such as ischaemic heart disease or signs of pulmonary embolism. In severe disease there may be signs of pulmonary hypertension such as peaked p waves or right ventricular hypertrophy |
| Full blood count (FBC) | This may identify anaemia as a cause of breathlessness or show evidence of secondary polycythaemia. |
| Urea and electrolytes (U&E) | |
| Theophylline level | If the patient is already on theophylline therapy |
| Sputum analysis | If sputum is purulent a sample should be sent for microscopy, culture and sensitivity |
| Blood cultures | If pyrexia present |
Learning bite
ABG analysis should be performed on arrival in patients who are breathless with acute exacerbations of COPD.