Emphysema overview: Difference between revisions
| Line 7: | Line 7: | ||
The term ''emphysema'' means "''swelling''" and derives from the [[Greek language|Greek]] {{lang|el|ἐμφυσᾶν}} ''emphysan'' meaning "''inflate''" - itself composed of ἐν ''en'', meaning "''in''", and φυσᾶν ''physan'', meaning "''breath, blast''".<ref>[http://dictionary.reference.com/browse/emphysema emphysema] at [[dictionary.com]]</ref> | The term ''emphysema'' means "''swelling''" and derives from the [[Greek language|Greek]] {{lang|el|ἐμφυσᾶν}} ''emphysan'' meaning "''inflate''" - itself composed of ἐν ''en'', meaning "''in''", and φυσᾶν ''physan'', meaning "''breath, blast''".<ref>[http://dictionary.reference.com/browse/emphysema emphysema] at [[dictionary.com]]</ref> | ||
{{#widget:priyapicture|src=http://upload.wikimedia.org/wikipedia/commons/9/9a/Barrowchest.JPG|alt=A lateral chest x-ray of a person with emphysema. Note the barrel chest and flat diaphragm.|width=300|height=300}} | {{#widget:priyapicture|src=http://upload.wikimedia.org/wikipedia/commons/9/9a/Barrowchest.JPG|alt=A lateral chest x-ray of a person with emphysema. Note the barrel chest and flat diaphragm.|width=300|height=300}} | ||
==Historical perspective== | |||
The terms chronic bronchitis and emphysema were formally defined at the CIBA guest symposium of physicians in 1959. COPD has probably always existed but has been called by different names in the past. Bonet described a condition of “voluminous lungs” in 1679. Matthew Baillie illustrated an emphysematous lung in 1789 and described the destructive character of the condition. The term COPD was first used by William Briscoe in 1965 and has gradually overtaken other terms to become established today as the preferred name for this disease. | |||
==Pathophysiology== | ==Pathophysiology== | ||
Emphysema is caused by loss of elasticity of the lung tissue, from destruction of structures supporting the [[alveoli]], and destruction of capillaries feeding the alveoli. The result is that the ''small airways'' collapse during exhalation, leading to an obstructive form of lung disease (airflow is impeded and air is generally "trapped" in the lungs in [[COPD|obstructive lung diseases]]). When toxins such as smoke are breathed into the lungs, the particles are trapped and cause a localized [[inflammation|inflammatory]] response. Chemicals released during the inflammatory response (e.g., elastase) can break down the walls of alveoli (alveolar septum). This leads to fewer but larger alveoli, with a decreased surface area and a decreased ability to absorb oxygen and exude carbon dioxide by diffusion. The activity of another molecule called alpha 1-antitrypsin normally neutralizes the destructive action of one of these damaging molecules. | Emphysema is caused by loss of elasticity of the lung tissue, from destruction of structures supporting the [[alveoli]], and destruction of capillaries feeding the alveoli. The result is that the ''small airways'' collapse during exhalation, leading to an obstructive form of lung disease (airflow is impeded and air is generally "trapped" in the lungs in [[COPD|obstructive lung diseases]]). When toxins such as smoke are breathed into the lungs, the particles are trapped and cause a localized [[inflammation|inflammatory]] response. Chemicals released during the inflammatory response (e.g., elastase) can break down the walls of alveoli (alveolar septum). This leads to fewer but larger alveoli, with a decreased surface area and a decreased ability to absorb oxygen and exude carbon dioxide by diffusion. The activity of another molecule called alpha 1-antitrypsin normally neutralizes the destructive action of one of these damaging molecules. | ||
Revision as of 18:45, 28 March 2012
|
Emphysema Microchapters |
|
Diagnosis |
|---|
|
Treatment |
|
Case Studies |
|
Emphysema overview On the Web |
|
American Roentgen Ray Society Images of Emphysema overview |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Emphysema is a long-term, progressive disease of the lungs that primarily causes shortness of breath. In people with emphysema, the tissues necessary to support the physical shape and function of the lungs are destroyed. It is included in a group of diseases called chronic obstructive pulmonary disease or COPD (pulmonary refers to the lungs). Emphysema is called an obstructive lung disease because the destruction of lung tissue around smaller sacs, called alveoli, makes these air sacs unable to hold their functional shape upon exhalation. Emphysema is most often caused by tobacco smoking and long-term exposure to air pollution.
The term emphysema means "swelling" and derives from the Greek ἐμφυσᾶν emphysan meaning "inflate" - itself composed of ἐν en, meaning "in", and φυσᾶν physan, meaning "breath, blast".[1]
Historical perspective
The terms chronic bronchitis and emphysema were formally defined at the CIBA guest symposium of physicians in 1959. COPD has probably always existed but has been called by different names in the past. Bonet described a condition of “voluminous lungs” in 1679. Matthew Baillie illustrated an emphysematous lung in 1789 and described the destructive character of the condition. The term COPD was first used by William Briscoe in 1965 and has gradually overtaken other terms to become established today as the preferred name for this disease.
Pathophysiology
Emphysema is caused by loss of elasticity of the lung tissue, from destruction of structures supporting the alveoli, and destruction of capillaries feeding the alveoli. The result is that the small airways collapse during exhalation, leading to an obstructive form of lung disease (airflow is impeded and air is generally "trapped" in the lungs in obstructive lung diseases). When toxins such as smoke are breathed into the lungs, the particles are trapped and cause a localized inflammatory response. Chemicals released during the inflammatory response (e.g., elastase) can break down the walls of alveoli (alveolar septum). This leads to fewer but larger alveoli, with a decreased surface area and a decreased ability to absorb oxygen and exude carbon dioxide by diffusion. The activity of another molecule called alpha 1-antitrypsin normally neutralizes the destructive action of one of these damaging molecules.