Hi everyone. Welcome to this module on Dyspnea. A common symptom experienced by many patients with chronic life-limiting illness. So, what is Dyspnea? The word dyspnea is derived from Greek roots "Dys" means difficult and "Pneuma" means breath. Dyspnea is an uncomfortable awareness of breathing. It is also described as severe shortness of breath, breathlessness, or having trouble breathing. The American Thoracic Society, a nonprofit organization with the purpose of improving care for many breathing related disorders, defines dyspnea as a personal experience of breathing discomfort that is made up of qualitatively, distinct sensations that vary in intensity. Patterned after the concept of total pain, the total dyspnea experienced stamps term connections among these four factors; physical, psychological, social, and spiritual. Total dyspnea describes the person's many concerns that come together to shape the symptom of uncomfortable awareness of breathing, and then to determine its impact. Dyspnea can be acute lasting hours to days or chronic if present for more than four weeks. Like pain, it may be continuous or it may come and go. In a healthy person, acute dyspnea can be caused by very active exercise like aerobics, running or biking, extreme temperatures, bad air quality, or high altitude can also make it worse. Other causes of acute dyspnea include having an allergic reaction or asthma attack, low blood pressure, smoking, pneumonia, anemia, or having a pulmonary embolism which is a blood clot in the lung. The most common causes of chronic dyspnea are having a diagnosis of asthma, chronic obstructive pulmonary disease which we call COPD, interstitial lung disease, heart disease, cancer, and obesity. Deconditioning of the body can also cause shortness of breath. About 40% of cancer patients report continuous dyspnea, and greater than 80% have intermittent shortness of breath about five to six times per day lasting approximately five minutes each. Often people with cancer experience fatigue due to their disease or treatment. This can lead to more episodes of shortness of breath. As breathing is a basic sensation of life, it's disturbance creates a sense of dread that leads to suffering. Dyspnea is often a problem for patients at the end of life. There was a large systematic review of multiple studies of patients with various illness types such as cancer, AIDS, heart disease, COPD, and kidney failure. Over 50% of patients complained of three major problems, pain, fatigue, and dyspnea. Of 5,862 patients with various diagnoses seen by palliative care teams over a three month time-frame, 89% reported some level of breathlessness despite treatment. So, how does this dyspnea occur in the physical sense? It's complicated but a person's heart and lungs transport oxygen throughout the body and remove carbon dioxide. Problems with either the heart or the lungs can affect breathing, and breathing is also regulated by the brain. It's a complex relationship between chemicals in the blood and in the air that we breathe. Oxygen and carbon dioxide levels and the amount of hemoglobin in blood all play a role. If blood carbon dioxide levels rise, the brain tells the body to increase the breathing rate. This can result in deeper or faster breaths. It also may lead to a feeling of not being able to catch your breath, and too much acid in the blood from an infection or other problem like being anemic, can also lead to an increased breathing rate and the feeling of shortness of breath. Next we'll talk about what it feels like to be short of breath. We'll also review other symptoms that can occur with dyspnea. Please join me.