<unk>  is defined as "uncomfortable sensation of breathing".<unk>  involves multiple qualitatively precise sensations, which derived from various pathophysiologic processes. Shortness of breath is consisted of eight different sensations, include rapid breathing, incomplete exhalation, shallow breathing, increased work or effort, feeling of suffocation, air hunger, chest tightness, and heavy breathing. Common pathophysiology of shortness of breath is a combination of sense of respiratory effort, chemoreceptors, mechanoreceptors, and afferent mismatch. Common Causes of<unk>  include anemia, foreign body aspiration, heart failure, pneumonia, pregnancy, and pulmonary edema.
Dyspnea
Hypernea
Apnea
Tachypnea
Orthopnea
Labored breathing
Fatigue  
Fatigue