-IBIS-1.5.0-
tx
respiratory system
emphysema
diagnoses
definition and etiology
definition:
Distention of the air spaces in the lungs distal to the terminal bronchiole with concurrent destruction of the alveolar walls. Emphysema is, with chronic bronchitis, a disease termed "Chronic Obstructive Pulmonary Disease" (COPD).
etiology:
Emphysema apparently is related to the effect of proteolytic enzymes on the alveolar septa. These enzymes are released by WBCs during their response to inflammatory processes. The leading factor that leads to a state of chronic inflammation in the lungs is smoking. In homozygotic alpha-one-antitrypsin deficiency, patients develop emphysema at a young age because they are lacking in the substance that inhibits proteolytic enzyme activity, even if the enzyme is not markedly increased due to inflammation. COPD is a major cause of disability and death in the U.S., second only to heart disease as a cause of disability. Men have been affected much more than women in the past, no doubt due to their more marked smoking; however, with the advent of increased smoking in women, the disease prevalence in females is also increasing.
signs and symptoms
signs and symptoms:
Many patients found to have had emphysema post-mortem had no symptoms while alive.
"Smoker's cough" will typically precede the onset of the disease.
Gradually progressing exertional dyspnea.
Cough: May be mild or severe.
Other findings that are not consistently seen or are only seen in very advanced cases:
» Barrel chest.
» Use of accessory muscles for breathing.
» Pursed-lip breathing.
» Tripod position when sitting (resting chin on hands) with associated calloused elbows.
» Cyanosis.
lab findings:
X-rays: Depressed diaphragm, radiolucency of the lungs, tenting of the diaphragm at the rib insertions.
Planograms: Detects bullae.
Isotopic lung scans.
Spirometric testing: Slowed forced air expiration and low maximum mid-expiratory flow.
Increased pCO2 and decreased pO2 in blood gases.
course and prognosis
Prognosis is tied to the rate of expiratory slowing. The disease is usually only palliated with treatment, and is gradually progressive leading to death.
differential diagnosis
Chronic bronchitis.
Asthma.
Pneumothorax.
footnotes