Exacerbations of COPD impose a high toll on the patient and on the NHS.
An exacerbation of COPD is a sustained worsening of the patient’s symptoms from their usual stable state and is acute in onset, beyond day-to-day variation and requires treatment change.
Symptoms may vary from a mild attack, with increased breathlessness and increased volume and purulence of sputum, to a severe attack with increased fluid retention (due to acute cor pulmonale), confusion and drowsiness.
Causes of exacerbations are mainly infective and/or due to environmental pollutants.
The initial assessment will look at whether immediate treatment is necessary (if there is inability to talk in sentences, drowsiness or acute cyanosis).
Otherwise a history should be taken of the present exacerbation, the presence of co-morbidities and symptoms that might suggest an alternative diagnosis, social support, previous exacerbations/hospital admissions and current treatment used in this episode.
The severity of the attack is assessed from the history and from the degree of tachypnoea and dyspnoea (including the use of accessory muscles).
A respiratory rate of more than 25/min and pulse rate higher than 110/min are suggestive of a severe attack. Pulse oximetry is very useful, with oxygen saturations of less than 90 per cent indicating the need for supplementary oxygen.
Measurements of lung function (FEV1 and peak flow) do not accurately reflect the severity of airflow obstruction in an acute attack and therefore need not be measured.
Chest and cardiovascular examination will help to differentiate an exacerbation of COPD from other causes of acute breathlessness, such as pulmonary oedema, pneumonia and pleural effusion.
Oxygen should be given if oxygen saturations are less than 90 per cent in air. It should be administered via a Venturi mask at low flow rates of two to four litres/min to maintain oxygen saturations between 90 and 93 per cent. Higher-flow oxygen can reduce the hypoxic drive in patients with COPD who are already hypercapnic and precipitate respiratory failure.
Short-acting bronchodilators (terbutaline, salbutamol) should be given at higher dosages and more frequently. metered dose inhalers (MDIs) should be used with a spacer device, and no advantage is conferred by using a nebuliser unless the patient is too breathless to use a MDI/spacer.
Oral corticosteroids (prednisolone 30–40mg) should be given for seven to 10 days in all patients where an increase in breathlessness interferes with daily activities. This reduces recovery time and improves lung function.
Antibiotics should be used where there is an increase in sputum purulence to hasten the resolution of symptoms. Amoxicillin 500mg three times daily for seven to 10 days is a good first choice (or a macrolide/tetracycline if the patient is allergic to penicillin).
Erdosteine is a mucolytic agent with antioxidant properties that limits bacterial adherence to the bronchial mucosa. It has recently been licensed for the management of exacerbations of COPD.
Patients should be encouraged to maintain their fluid intake and be offered advice on control of breathing.
When to review the acute episode will be dictated by the severity of the initial presentation and concerns about social support.
Dr Gruffydd-Jones is a GP in Box, Wiltshire, and member of the General Practice Airways Group