INTRODUCTION

Dyspnea is a term used to characterize a subjective experience of breathing discomfort that is comprised of qualitatively distinct sensations that vary in intensity. The experience derives from interactions among multiple physiological, psychological, social, and environmental factors that may induce secondary physiological and behavioral responses [1].

Dyspnea, or breathlessness, encompasses multiple somatic perceptions that are variously described as air hunger, increased effort of breathing, chest tightness, rapid breathing, incomplete exhalation, or a feeling of suffocation. Dyspnea is a multidimensional symptom, consisting of affective as well as physical aspects. Its presence and severity cannot be inferred from physical examination or laboratory investigations – we must ask about it. It can occur in the absence of physical signs (eg, rapid, deep, or labored breathing) or abnormal findings on investigations such as blood gases or chest radiographs.

Palliative care is an interdisciplinary medical specialty that focuses on preventing and relieving suffering and on supporting the best possible quality of life for patients and their families facing life-threatening or other serious illnesses.  The primary tenets of palliative care are symptom management; establishing goals of care that are in keeping with the patient’s values and preferences; consistent and sustained communication between the patient and all those involved in his or her care; psychosocial, spiritual, and practical support both to patients and their family caregivers, and coordination across sites of care. Palliative care aims to relieve suffering in all stages of disease and is not limited to end of life care. Within an integrated model of medical care, palliative care is provided at the same time as curative or life-prolonging treatments. (See "Palliative care: Benefits, services, and models of care".)

This topic focuses on the assessment and care of patients with advanced terminal illness who develop dyspnea. An approach to the diagnosis of dyspnea in adults and the management of specific causes of dyspnea are addressed elsewhere. (See "Approach to the patient with dyspnea" and "Symptom-based management of amyotrophic lateral sclerosis", section on 'Respiratory management' and "End of life considerations for heart failure patients", section on 'Dyspnea' and "Management of acute exacerbations of chronic obstructive pulmonary disease" and "Treatment of acute decompensated heart failure: General considerations" and "Treatment of acute decompensated heart failure: Components of therapy".)

OVERVIEW

Prevalence — Dyspnea is common in patients with advanced life-threatening illness of all types (table 1). It is one of the most common symptoms reported in patients with a terminal cancer in the last six months of life (figure 1). In a systematic review of the prevalence of 11 symptoms in patients with advanced illness from any of five diagnoses (cancer, AIDS, heart disease, chronic obstructive pulmonary disease [COPD] or renal disease), dyspnea was one of only three symptoms to be present in >50 percent of patients from all five groups [2]. Regardless of diagnosis, both the prevalence and severity of dyspnea tend to increase over time, particularly in the last six months of life [3,4].