Causes of Acute Respiratory Distress Syndrome

• Severe, widespread infection (sepsis)

• Pneumonia

• Severe, low blood pressure (shock)

• Aspiration (inhalation) of food into the lung

• Several blood transfusions

• Injury to the lungs from breathing high, concentrations of oxygen

• Pulmonary embolism

• Chest injury

• Burns

• Near drowning

• Cardiopulmonary bypass surgery

• Inflammation of the pancreas (pancreatitis)

• Overdose of a drug, such as heroin, methadone, propoxyphene, or aspirin

 

Text B. Bronchitis.

Bronchitis is an inflammation of the bronchi usually caused by an infection.

The condition is usually mild and eventually heals completely. But bronchitis may be serious in chronically ill people with heart or lung disease and in the elderly.

Causes

Infectious bronchitis occurs most often in winter. It may be caused by viruses, bacteria, and espe­cially the bacteria-like organisms Mycoplasma pneumoniae and Chlamydia. Smokers and people who have chronic lung or airway diseases that interfere with clearing inhaled particles from the bronchi may have repeated attacks. Recurring infections may result from chronic sinusitis, bronchiectasis, allergies, and, in children, enlarged tonsils and adenoids.

Irritative bronchitis may be caused by various kinds of dust; fumes from strong acids, ammonia, some organic solvents, chlorine, hydrogen sulfide, sulfur dioxide, and bromine; the air pollution irritants ozone and nitrogen dioxide; and tobacco and other smoke.

Symptoms and Diagnosis

Infectious bronchitis often starts with symp­toms of a common cold: runny nose, tiredness, chills, back and muscle aches, slight fever, and sore throat. The start of a cough usually signals the beginning of bronchitis. The cough is dry at first and may remain so, but a person often coughs up small amounts of white or yellow spu­tum after a day or two. Later, a person may cough up much more sputum, which may be yellow or green. Someone with severe bronchitis may have a high fever for 3 to 5 days, after which most symptoms improve. The cough, however, may last several weeks. If the airways are obstructed, the person may be short of breath. Wheezing, especially after coughing, is common. Pneumonia may develop.

A diagnosis of bronchitis is usually made on the basis of the symptoms, especially the appearance of the coughed-up sputum. If symptoms persist, a chest x-ray may be needed to be sure the person hasn't developed pneumonia.

Treatment

Adults may take aspirin or acetaminophen to reduce fever and general feelings of illness, but children should take only acetaminophen. Rest­ing and drinking plenty of fluids help.

Antibiotics are used for people with symptoms that suggest their bronchitis results from a bac­terial infection (such as those who cough up yellow or green sputum and those whose fever remains high) and for people with preexisting lung disease. Adults may receive trimethoprim-sulfamethoxazole, tetracycline, or ampicillin. Often when a Mycoplasma pneumoniae infection is suspected, erythromycin is given. For children, amoxicillin is the usual choice. Antibiotics don't help if the infection is caused by a virus.

When symptoms persist or recur or when bron­chitis is unusually severe, a laboratory culture of coughed-up sputum may show whether a differ­ent antibiotic is needed.

Notes:

recurrent рецидивирующий

irritative раздражающий

fumes пары, испарения

persist сохраняться, продолжать существовать

 

Occupational Lung Diseases

Text A. Introduction.

Occupational lung diseases are caused by harmful particles, mists, vapors, or gases inhaled while a person works. Where in the airways or lungs an inhaled substance ends up and what type of lung disease develops depend on the size and kind of particles inhaled. Larger particles may get trapped in the nose or large airways, but the smallest ones reach the lungs. There, some par­ticles dissolve and may be absorbed into the bloodstream; most solid particles that don't dis­solve are removed by the body's defenses.

The body has several means of getting rid of inhaled particles. In the airways, mucus coats par­ticles so they can be coughed up more easily. In the lungs, special scavenger cells engulf most par­ticles and render them harmless.

Different types of particles produce different reactions in the body. Some particles - plant pol­lens, for example - can cause allergic reactions such as hay fever or a type of asthma. Particles such as coal dust, carbon, and tin oxide don't produce much of a reaction in the lungs. Other particles, such as quartz dust and asbestos, may cause permanent scarring of lung tissue (pulmo­nary fibrosis). In large enough quantities, certain particles, such as asbestos, can cause cancer in smokers.

Notes:

occupational lung diseases профессиональные болезни легких

harmful вредный, пагубный

dissolve растворять

adsorbe всасывать

seavenger cells клетки - чистильщики

pollen пыльца

 

Text B. Silicosis.

Silicosis is permanent scarring of the lungs caused by inhaling silica (quartz) dust.

Silicosis, the oldest known occupational lung disease, develops in people who have inhaled sil­ica dust for many years. Silica is the main constit­uent of sand, so exposure is common among metal miners, sandstone and granite cutters, foundry workers, and potters. Usually, symptoms appear only after 20 to 30 years of exposure to the dust. However, in occupations such as sand­blasting, tunneling, and manufacturing abrasive soaps, in which high levels of silica dust are pro­duced, symptoms may appear in less than 10 years.

When inhaled, silica dust passes into the lungs, and scavenger cells such as macrophages engulf it. Enzymes released by the scavenger cells cause the lung tissue to scar. At first, the scarred areas are tiny round lumps (simple nodular silicosis), but eventually they may aggregate into large masses (conglomerate silicosis). These scarred areas can't transfer oxygen into the blood normally. The lungs become less flexible, and breathing takes more effort.

Symptoms and Diagnosis

People with simple nodular silicosis have no trouble breathing, but they may cough and pro­duce sputum because their large airways are irritated, a condition called bronchitis. Conglom­erate silicosis may cause coughing, sputum pro­duction, and severe shortness of breath. At first, the shortness of breath may occur only during exercise, but eventually it occurs even during rest. Breathing may worsen for 2 to 5 years after the person stops working with silica. The lung damage strains the heart and can lead to heart failure, which can be fatal. Also, when exposed to the organism that causes tuberculosis (Mycobacterium tuberculosis), people with silicosis are three times more likely to develop tuberculosis than people without silicosis.

Silicosis is diagnosed when someone who has worked with silica has a chest x-ray that shows the distinctive patterns of scarring and nodules.

Prevention

Controlling the dust in the workplace can help prevent silicosis. When dust can't be controlled, as may be true in the sandblasting industry, work­ers should wear hoods that supply clean external air or masks that completely filter out the tiny particles. Such protection may not be available to all people working in a dusty area (for example, painters and welders), so whenever possible, abrasives other than sand should be used.

Workers exposed to silica dust should have reg­ular chest x-rays - every 6 months for sandblasters and every 2 to 5 years for other workers - so that problems can be detected early. If the x-rays show silicosis, a doctor will probably advise the worker to avoid continued exposure to silica.

Treatment

Silicosis can't be cured. However, if a person with an early stage of the illness stops being ex­posed to silica, the progression of silicosis may stop. A person who has difficulty breathing may benefit from the treatments used for chronic ob­structive pulmonary disease, such as drug ther­apy to keep the airways open and free of secre­tions. Because people with silicosis have a high risk of developing tuberculosis, they should have regular checkups that include a tuberculosis skin test.

Notes:

sandstone песчаник

foundry литейный цех

scavenger очиститель, уборщик мусора

scar рубец; зарубцовываться

expose подвергать, подвергаться воздействию

strain напряжение, натяжение; напрягать, натягивать

welder сварщик

 

Text C. Black Lung.

Black lung (coal workers' pneumoconiosis) is a lung disease caused by deposits of coal dust in the lungs.

Black lung results from inhaling coal dust over a long time. In simple black lung, coal dust collects around the small airways (bronchioles) of the lungs. Although coal dust is relatively inert and doesn't provoke much reaction, it spreads throughout the lungs and shows up as tiny spots on an x-ray. The coal dust doesn't block the air­ways. Nevertheless, every year 1 to 2 percent of the people with simple black lung develop a more serious form of the disease called progressive massive fibrosis, in which large areas of the lung (at least 1/2 inch in diameter) become scarred. Pro­gressive massive fibrosis may worsen even after a person is no longer exposed to coal dust. Lung tissue and the blood vessels in the lungs can be destroyed by the scarring.

In Caplan's syndrome, a rare disorder that can affect coal miners who have rheumatoid arthritis, large round nodules of scarring develop quickly in the lung. Such nodules may form in people who have had significant exposure to coal dust, even if they don't have black lung.

Symptoms and Diagnosis

Simple black lung usually doesn't cause symp­toms. However, many people with this disease cough and easily become short of breath because they also have emphysema (from cigarette smok­ing) or bronchitis (from cigarette smoking or toxic exposure to other industrial pollutants). The severe stages of progressive massive fibrosis, on the other hand, cause coughing and often dis­abling shortness of breath.

A doctor makes the diagnosis after noting char­acteristic spots on the chest x-ray of a person who has been exposed to coal dust for a long time - usually someone who has worked underground at least 10 years.

Prevention and Treatment

Black lung can be prevented by adequately sup­pressing coal dust at a work site. Coal workers should have chest x-rays every 4 to 5 years, so that the disease can be detected at an early stage. If the disease is detected, the worker should be transferred to an area where coal dust levels are low to prevent progressive massive fibrosis.

Prevention is crucial because there's no cure for black lung. A person who can't breathe freely may benefit from the treatments used for chronic obstructive pulmonary disease, such as drug therapy to keep the airways open and free of secretions.

 

Notes:

deposit отложение

lead свинец

sandblaster пескоструйный аппарат

tin олово

hemp конопля, пенька

jute джут

flax лен