Breathlessness in advanced disease

Breathlessness is a distressing symptom which arises in many diseases and has several pathophysiological causes, involving the interplay between peripheral and central chemoreceptors, lung receptors, chest wall and diaphragmatic muscles and cortical processing. Older people and patients with cachexia are more susceptible to breathlessness on exertion. Most patients can be assessed with physical examination and simple investigations including Hb, oxygen saturation, ECG and imaging (X-ray and ultrasound). Research shows that opioid receptors are important in the central medullary chemoreceptors but also in the cortical areas. Thus, careful use of opioids can reduce the sensation of breathlessness without compromising ventilatory control. Benzodiazepines also reduce breathlessness, probably by their anxiolytic and sedative actions. The combination of opioid and short-acting benzodiazepine is especially useful. Nebulized furosemide is a new approach which requires further research. Oxygen is indicated if the saturation falls but increased airflow around the face, e.g. with a fan, can also help. The combination of helium with oxygen may be more effective than oxygen alone. Non-invasive ventilation may be necessary in severe cases, e.g. neuromuscular disease. Non-medical approaches, including breathing training and relaxation, can help. Infusions of carefully titrated opioid and midazolam can be used in the dying patient, together with an anticholinergic if upper airways secretions are causing ‘death rattle’.