Dyspnoea

Evidence summary

Dyspnoea (shortness of breath) is described as 'an uncomfortable awareness of breathing'. [1] It is a subjective symptom which may not correlate with measurable physical abnormalities such as hypoxia. Treating the dominant cause of breathlessness, including the contributing co-morbidities, is likely to be most effective, but is not always possible.

Shortness of breath becomes more frequent in patients as their disease progresses, [2] is associated with a poorer prognosis, [3] and is usually multifactorial in patients with advanced disease. The effective assessment and management of dyspnoea is increasingly regarded as an important quality measure in palliative care. [3]

Dyspnoea may serve as an early trigger for referral to palliative care services. [4] Patients experiencing breathlessness find the issues that most impact their lives are the loss of control, social participation and the impact breathlessness has on their relationships. [5] Numerous assessment tools for dyspnoea exist, but there is no consensus about which is the optimal tool for palliative care. [3] It has been proposed that use of the numerical rating scale and visual analog scale may be appropriate. [3]

Evidence supports the use of either oral or parenteral opioids for relieving the symptom of dyspnoea, and most of this evidence relates to morphine. [6,7] Opioids are the preferred treatment in refractory dyspnoea in patients with advanced cancer. [8] There is limited evidence to support the use of nebulised opioids, however patients report a subjective improvement when they are used. [6] A recent systematic review identified some evidence for the efficacy of fentanyl for dyspnoea. [9,10] Combining opioids with bronchodilators has been shown to be effective. [11] There is low quality evidence for the use of opioids to manage dyspnoea in chronic heart failure. [12] There is limited evidence in paediatric palliative care, although opioids are used in clinical practice. [13,14]

A recent meta-analysis has shown that oxygen does not improve symptoms of dyspnoea in cancer patients who are mildly or non-hypoxaemic, although there may be a sub-population who do experience benefit. [15] A systematic review found no strong evidence for the benefit of oxygen in patients with dyspnoea and advanced disease from any cause, although the numbers studied were very small. [16] There does appear to be a knowledge gap regarding the appropriate use of oxygen in breathlessness for health care professionals. [17] 

The use of nebulised frusemide for dyspnoea has been investigated. A systematic review suggests it is a promising approach, although the included studies were small and diverse. [18] There are some positive results to support its use in COPD but limited evidence for use in cancer patients and paediatrics. [14]

If drainage of a malignant pleural effusion is required and is clinically appropriate, evidence supports the effectiveness of thoracoscopic talc pleurodesis. There is also low level evidence to support the safety and effectiveness of tunnelled pleural catheters in this setting. [19]

There is a growing body of evidence to support the use of non-pharmacological management of dyspnoea. In general these therapeutic interventions focus on physical activity (including exercise and activity pacing), breathing techniques, and technology based interventions (hand-held fans and neuromuscular electrical stimulation) and psychological interventions. [20] Many of these interventions remain poorly investigated and the therapeutic benefit derived from them may be as general health benefits rather than specific outcomes for the management of dyspnoea. [20] Multi-disciplinary team interventions including breathlessness clinics may improve management of dyspnoea in palliative care patients with lung cancer. [21] For Chronic Obstructive Pulmonary Disease (COPD) patients who are able to participate in pulmonary rehabilitation, there is evidence of a clinically significant benefit in terms of dyspnoea, fatigue and wellbeing [22] and home-based physiotherapy interventions may also offer benefit. [23,24]

Benzodiazepines are frequently prescribed for management of distress associated with dyspnea, but have not been shown to be of benefit. They cause more drowsiness than opioids, and should only be used if non-pharmacological methods and opioids have failed to control the symptom. [25,26]

There is limited evidence to support the use of non-invasive ventilation to relieve the experience of dyspnoea in COPD. [27]

Refractory dyspnoea at the end-of-life, which causes severe distress and does not respond to symptom management is a challenging problem. In the rare instances where dyspnoea remains refractory at end of life, light sedation may be considered. Guidelines for sedation for refractory symptoms at the end of life have been proposed. [28]

Practice implications

• Routine assessment of patients for dyspnoea is essential in palliative care, and assessment needs to include a measure both of intensity of the symptom, and of any associated distress or impairment. [3]
• Opioids are the first line pharmacological management for dyspnoea in patients with advanced disease or cancer.
• Oxygen prescription should be individualised, based on the presence of hypoxia and a formal assessment of benefit after a therapeutic trial in the individual patient. [17,29]
• There is growing evidence for the non-pharmacological approach to dyspnoea in the palliative care setting. Non-pharmacological interventions offer an additional strategy to help patients manage their symptoms. Interventions should be tailored to the individual patient. Those who are very disabled by dyspnoea or close to the end of life may be best cared for with a pharmacological approach.
• Guidelines for sedation for refractory symptoms at the end of life have been proposed. [28]