Dyspnea and its interaction with pain

Excerpt

A wide range of respiratory sensations such as shown in Table 1 can be sensed by humans. Among these respiratory sensations, the last three sensations, i.e., chest tightness, work/effort sensation, and respiratory discomfort (air hunger), are the main sensations that constitute the sensation of “dyspnea.” Although dyspnea is often defined as an uncomfortable sensation of breathing, this definition is too simple to understand the precise mechanisms of dyspnea. According to the definition proposed by the American Thoracic Society [1], dyspnea is a term used to characterize a subjective experience of breathing discomfort that consists of qualitatively distinct sensations which vary in intensity. This broad definition may contribute to the better understanding of mechanisms of dyspnea and improvement of therapeutic approaches to dyspnea. Although it is the primary symptom of many diseases of the respiratory systems, dyspnea can also arise in other forms of diseases such as those affecting cardiovascular or neuromuscular systems. Dyspnea is commonly observed in several clinical settings such as cancer, chronic obstructive pulmonary disease, and cardiac failure, and it is not rare for anesthesiologists to take care of these patients in the operating room, intensive care unit, or palliative care unit. …