Hypersensitivity pneumonitis (also called allergic alveolitis) is a disease in which the air sacs (alveoli) of the lungs become inflamed when certain dusts are inhaled to which the person is sensitized or allergic.

These dusts contain organic substances, such as fungus spores from moldy hay or the droppings of birds.

When a person inhales such dusts the first time, no problem is noticed. But, after repeated exposure to the dust some people may develop symptoms. The tiny air sacs in the lung known as alveoli become inflamed, their walls fill with white blood cells, and sometimes the sacs fill with fluid. If the disease recurs as a result of continued or repeated exposure to the offending dusts, parts of the lung may develop fibrous scar tissue and can no longer function normally in breathing.

WHAT ARE THE SYMPTOMS?

The symptoms of an acute attack are similar to those of the flu and appear some 4-6 hours after the person breathes the offending dust. These symptoms include chills, fever, dry cough, shortness of breath, a tight feeling in the chest, and tiredness. The symptoms may persist for as little as 12 hours or as long as 10 days. Between attacks the person may have no symptoms and feel quite normal.

After repeated exposure to the dust, chronic cough may develop with excessive sputum production containing pus, and eventually there may be chronic shortness of breath. The person may also show loss of appetite and weight loss.

WHO GETS HYPERSENSITIVITY PNEUMONITIS?

Hypersensitivity pneumonitis occurs most often in people exposed to certain organic dusts in their daily work or living, especially dusts which contain fungus spores from mold.

Only a small proportion of people who are exposed, perhaps 5 to 20 percent, develop the disease. When there is frequent exposure to high concentrations of the offending substances, the likelihood of developing hypersensitivity pneumonitis is greatest.

WHAT CAUSES HYPERSENSITIVITY PNEUMONITIS?

The disease is caused by organic material that is inhaled as a fine dust. Sensitization (allergy) develops over a period of several months to a number of years.

Farmer’s lung is the best-known example. It is caused by an organism that grows on hay, straw, or grains, and by other organic materials found on farms. Also known to cause hypersensitivity pneumonitis are dusts from moldy sugar cane and barley, maple bark, cork, animal hair, bird feathers and droppings, mushroom compost, coffee beans, and paprika. Often the disease is named for the occupations: for example mushroom-worker’s lung or paprika-splitter’s lung. The organism of farmer’s lung also grows in the water of both commercial and home humidification systems, particularly if they are not adequately maintained.

HOW IS HYPERSENSITIVITY PNEUMONITIS DIAGNOSED?

A careful, detailed history is necessary so that the occurrence of symptoms can be related to environmental exposure. Laboratory tests of the patient’s blood and identification of specific molds from material at the workplace may help. Chest X-ray films and lung function tests may show effects of the disease during acute episodes or in the chronic stage of the disease – but they may be normal between episodes when the patient is without symptoms. Also chest X-ray and pulmonary function test results are not specific for hypersensitivity pneumonitis, and positive results may be due to other causes. Inhalation of the materials to which the person is sensitive (challenge test) may be necessary to confirm the diagnosis. The challenge test should be done only under the expert medical supervision of a specialist. Sometimes, a lung biopsy is needed to distinguish it from other lung diseases.

IS HYPERSENSITIVITY PNEUMONITIS PREVENTABLE?

Properly dried and stored farm products are unlikely to cause hypersensitivity pneumonitis because the particular organism causing farmer’s lung grows only in moist conditions. Other approaches to prevention are to reduce exposure by proper ventilation and the use of respiratory protection (masks).

If a worker begins to have symptoms of hypersensitivity pneumonitis due to occupational exposure, the process can be stopped if it is identified early enough. Permanent lung damage is prevented by eliminating the exposure. If control measures do not work or are not feasible, it may be necessary to change jobs, even though doing so may be difficult for many reasons. Therefore the medical necessity for a change should be determined only after careful evaluation to establish the diagnosis and specific cause.

WHAT CAN BE DONE TO TREAT HYPERSENSITIVITY PENUMONITIS?

Avoidance of the offending dust is the single most important measure because in the early stages the disease is completely reversible.

Most drugs are of limited value in treatment; antihistamines and bronchodilators are ineffective. Steroids can relieve the symptoms of acute attacks but do not cure the disease. Recovery from acute attacks may take as long as three weeks. Residual lung damage in the form of pulmonary fibrosis is permanent and may occur even after symptoms have disappeared. Avoiding exposure in the first place eliminates any possibility of later permanent damage.

DOES SMOKING AFFECT HYPERSENSITIVITY PNEUMONITIS?

There is no evidence that cigarette smoking helps cause hypersensitivity pneumonitis. It may, however, aggravate the symptoms of a person who has the disease. And smokers are likely to get complicating lung diseases, such as emphysema, chronic bronchitis, or lung cancer.

ARDS, or acute respiratory distress syndrome, is a lung condition that leads to low oxygen levels in the blood. ARDS can be life threatening. This is because your body's organs, such as the kidneys and brain, need oxygen-rich blood to work properly.

ARDS usually occurs in people who are very ill with another disease or who have major injuries. Most people are already in the hospital when they develop ARDS.

What Causes ARDS?

Many conditions or factors can directly or indirectly injure the lungs and lead to ARDS. Some common ones are:

• Sepsis. This is a condition in which bacteria infect the bloodstream.
• Pneumonia. This is an infection in the lungs.
• Severe bleeding due to an injury to the body.
• An injury to the chest or head, like a severe blow.
• Breathing in harmful fumes or smoke.
• Inhaling vomited stomach contents from the mouth.

It's not clear why some very sick or seriously injured people develop ARDS and others don't. Researchers are trying to find out why ARDS develops and how to prevent it.

Who Is At Risk for ARDS?

People at risk for ARDS have a condition or illness that can directly or indirectly injure their lungs.

Direct Lung Injury

Conditions that can directly injure the lungs include:

• Pneumonia. This is an infection in the lungs.
• Breathing in harmful fumes or smoke.
• Inhaling vomited stomach contents from the mouth.
• Severe acute respiratory syndrome (SARS). This is a type of pneumonia.
• Using a ventilator. This is a machine that helps people breathe, but, rarely, it can injure the lungs.
• Nearly drowning.

Indirect Lung Injury

Conditions that can indirectly injure the lungs include:

• Sepsis. This is a condition in which bacteria infect the bloodstream.
• Severe bleeding due to an injury to the body or having many blood transfusion.
• An injury to the chest or head, like a severe blow.
• Pancreatitis (PAN-kre-a-TI-tis). This is a condition in which the pancreas becomes irritated or infected. The pancreas is a gland that releases enzymes and hormones.
• Fat embolism (EM-bo-lizm). This is a condition in which fat blocks an artery. A physical injury, like a broken bone, can lead to a fat embolism.
• Drug overdose.

What Are the Signs and Symptoms of ARDS?

The first signs and symptoms of ARDS are feeling like you can't get enough air into your lungs, rapid breathing, and low oxygen levels in the blood.

Other signs and symptoms depend on the cause of the condition. They may occur before ARDS develops. For example, if pneumonia is causing ARDS, you may have a cough and fever before you feel short of breath.

Sometimes, people with ARDS develop signs and symptoms such as low blood pressure, confusion, and extreme tiredness. This may mean that the body's organs, such as the kidneys and heart, aren't getting enough oxygen-rich blood.

Most people who develop ARDS are in the hospital for another serious health problem. Rarely, people who aren't hospitalized have health problems (such as severe pneumonia) that lead to ARDS.

How Is ARDS Treated?

ARDS is treated with oxygen, fluids, and medicines. Treatments are done in a hospital's intensive care unit.

The main goals of treating ARDS are to get oxygen to your lungs and organs (like the brain and kidneys) and treat the underlying condition that's causing ARDS.

Oxygen

First, your doctor will try to give you extra oxygen through soft, plastic prongs that fit into your nose, or through a mask that fits over your mouth (or mouth and nose).

If your oxygen level doesn't increase or it's still hard for you to breathe, your doctor will give you oxygen through a breathing tube. The flexible tube will be inserted through your mouth or nose and into your windpipe.

Before inserting the tube, your doctor will squirt or spray a liquid medicine into your throat (and possibly your nose) to make it numb. This helps prevent coughing and gagging when the tube is inserted. Your doctor also will give you medicine, through an intravenous (IV) line into your bloodstream, to make you sleepy and relaxed.

The breathing tube will be connected to a machine that helps you breathe (a ventilator). The ventilator will fill your lungs with oxygen-rich air.

Your doctor will adjust the ventilator often to help your lungs get the right amount of oxygen. This also will help prevent any further injury to your lungs from the pressure of the ventilator.

The breathing tube and ventilator are used until you can breathe on your own. If you need a ventilator for more than a few days, your doctor may do a tracheotomy (tra-ke-OT-o-me). This involves making a small cut in your neck to create an opening to the windpipe. Your doctor will place the breathing tube directly into the windpipe. The tube is then connected to the ventilator.

Fluids

Fluids may be given to improve the flow of blood through your body and to provide nutrition. Your doctor will make sure you get the right amount of fluids.

Too much fluid can fill the lungs, making it harder to get the oxygen you need. Not enough fluid can limit blood and oxygen flow to the body's organs. Fluids usually are given through an IV line inserted in one of your blood vessels.

Medicines

Your doctor may give you medicines to prevent and treat infections and to relieve discomfort.

Complications From ARDS

If you have ARDS, you can develop other medical problems while in the hospital. The most common are infections, pneumothorax (noo-mo-THOR-aks; collapsed lung), lung scarring, and blood clots.

• Infections. Being in the hospital and lying down for a long time can make you prone to infections, such as pneumonia. Being on a ventilator also can put you at higher risk for infections. Infections can be treated with antibiotics.
• Pneumothorax. This is a condition in which air or gas collects in the space around the lungs, which can cause one or both lungs to collapse. The pressure of the air from a ventilator can cause this condition. Your doctor will put a tube into your chest to remove the air and let your lung(s) expand again.
• Lung scarring. ARDS causes the lungs to become stiff (scarred) and makes it hard for them to expand and fill with air. Being on a ventilator also can cause lung scarring. Often, lung scarring heals before you leave the hospital.
• Blood clots. Lying down for long periods can cause blood clots to form in your body. A blood clot that forms in a vein deep in your body is called a deep vein thrombosis. This type of blood clot can break off, travel through the bloodstream to the lungs, and block blood flow. This is called pulmonary embolism.

Definition

Metastatic lung cancer is cancer that starts somewhere else in the body and spreads to the lungs.

Alternative Names

Lung metastases

Causes, incidence, and risk factors

Metastatic tumors in the lungs are malignancies (cancers) that developed at other sites and spread via the blood stream to the lungs. Common tumors that metastasize to the lungs include breast cancer, colon cancer, prostate cancer, sarcoma, bladder cancer, neuroblastoma, and Wilm's tumor. However, almost any cancer has the capacity to spread to the lungs.

Symptoms

• Cough
• Bloody sputum
• Shortness of breath
• Weight loss
• Weakness
• Rib cage pain

Signs and tests

• Chest x-ray
• Chest CT scan
• Cytologic studies of pleural fluid or sputum
• Bronchoscopy
• Lung needle biopsy
• Surgical lung biopsy

Treatment

In most cases, metastatic cancer to the lung is a sign that the cancer has spread into the bloodstream. Usually cancer will be present even in places not seen by CT scans. In these circumstances, removing the visible tumors by surgery is usually not beneficial. Chemotherapy is usually the treatment of choice.

Cure is unlikely in most cases. Patients with testicular cancer or lymphoma, however, have a higher likelihood of long-term survival and cure compared with those with most other cancers.

In some circumstances in which the primary tumor has been removed and cancer has spread to only limited areas of the lung, the lung metastases can be removed surgically with the goal of long-term survival or, occasionally, cure.

Radiation therapy, the placement of stents inside the airways, or laser therapy are sometimes used but are less common than surgery or chemotherapy.

Support Groups

The stress of illness can often be helped by joining a support group where members share common experiences and problems. For this condition, see cancer support group.

Expectations (prognosis)

Living more than 5 years with metastatic cancer to the lungs is uncommon. Rarely, patients with certain types of cancer (sarcoma, renal cell carcinoma, bladder cancer, colon cancer, or melanoma) that has only spread a limited amount to the lung can be cured with surgery.

In some cases, cancer (particularly lymphoma or testicular cancer) that has spread to the lung can be cured with chemotherapy. But in general, lung metastases are a sign of widespread cancer with a poor survival rate.

Complications

• Side effects of chemotherapy and radiation therapy
• Further spread of the cancer
• Pleural effusions (fluid between the lung and chest wall), which can cause shortness of breath
• Pericardial effusions (fluid around the heart), which can cause shortness of breath

Calling your health care provider

Patients with a history of cancer who develop persistent cough, bloody sputum (coughing up blood), shortness of breath, unexplained weight loss, or other significant changes in their health should contact their health care provider.

Prevention

Not all cancers can be prevented, but many can be by not smoking, eating a healthy diet, exercising regularly, and keeping alcohol consumption moderate.

Pulmonary (PULL-mun-ary) arterial hypertension (PAH) is continuous high blood pressure in the pulmonary artery. The average blood pressure in a normal pulmonary artery is about 14 mmHg when the person is resting. In PAH, the average is usually greater than 25 mmHg.

PAH is a serious condition for which there are treatments but no cure. Treatment benefits many patients.

The pulmonary arteries are the blood vessels that carry oxygen-poor blood from the right ventricle (VEN-trih-kul) in the heart to the small arteries in the lungs. In PAH, three types of changes may occur in the pulmonary arteries:

• The muscles within the walls of the arteries may tighten up. This makes the inside of the arteries narrower.
• The walls of the pulmonary arteries may thicken as the amount of muscle increases in some arteries. Scar tissue may form in the walls of arteries. As the walls thicken and scar, the arteries become increasingly narrow.
• Tiny blood clots may form within the smaller arteries, causing blockages.

There is less room for the blood to flow through these narrower arteries. The arteries may also stiffen. Over time, some of the arteries may become completely blocked.

The narrowing of the pulmonary arteries causes the right side of heart to work harder to pump blood through the lungs. Over time, the heart muscle weakens and loses its ability to pump enough blood for the body's needs. This is called right heart failure. Heart failure is the most common cause of death in people with PAH.

There are two types of PAH:

• Primary pulmonary arterial hypertension (PPAH) is inherited or occurs for no known reason.
• Secondary pulmonary arterial hypertension (SPAH) either is caused by or occurs because of another condition. The conditions include chronic heart or lung disease, blood clots in the lungs, or a disease like scleroderma (skler-o-DER-ma).

About 300 new cases of PPAH are diagnosed in the United States each year. SPAH is much more common.

Doctors have learned a lot about PAH in recent years. More treatments are now available. Researchers are also studying several promising new treatments that may prolong lives as well as improve the quality of life for people living with PAH.

Other Names for Pulmonary Arterial Hypertension

• Idiopathic pulmonary arterial hypertension
• Sporadic primary pulmonary hypertension
• Familial primary pulmonary hypertension
• Secondary pulmonary arterial hypertension
• Pulmonary hypertension

What Causes Pulmonary Arterial Hypertension?

Certain factors appear to increase your chances of developing pulmonary arterial hypertension (PAH). They include:

• Use of appetite suppressants, especially fenfluramine (fen-FLOO-ra-men) and dexfenfluramine (deks-fen-FLOO-ra-men)
• Chronic use of cocaine or amphetamines
• HIV infection
• Liver disease
• Connective tissue diseases, such as scleroderma or lupus erythematosus

Doctors do not know what causes primary pulmonary arterial hypertension (PPAH), although it is inherited in some people. Recently, researchers discovered a defect in a gene that can lead to changes in the pulmonary arteries like those seen in PPAH. They think that other genes may be involved as well. As we learn more about how different genes work in the development of PPAH, better treatments and perhaps a preventive treatment or cure will be found.

Secondary pulmonary arterial hypertension (SPAH) is caused by a variety of conditions. Chronic obstructive pulmonary disease is the most common cause in adults.

Other Conditions That Can Lead to SPAH

• Obstructive sleep apnea
• Congenital heart defects
• Chronic blood clots in the pulmonary artery

PAH affects men and women of all ages, from very young children to seniors, and people of all racial and ethnic backgrounds.

PPAH is most common in women in their thirties and men in their forties. Twice as many cases are reported in women as in men.

What Are the Signs and Symptoms of Pulmonary Arterial Hypertension?

Difficulty breathing or shortness of breath (dyspnea) is the main symptom of pulmonary arterial hypertension (PAH). If you have PAH, you may feel that it is difficult to get enough air.

Other Common Signs and Symptoms

• Fatigue
• Dizziness
• Fainting spells (syncope)
• Swelling in the ankles or legs (oedema)
• Bluish lips and skin (cyanosis)
• Chest pain
• Racing pulse
• Palpitations (a strong feeling of a fast heartbeat)

As the disease advances:

• The pumping action of your heart grows weaker.
• Your energy decreases.

In the more advanced stages, you:

• Are able to perform very little activity
• Have symptoms even when resting
• May become completely bedridden

Limitations on Physical Activity

Doctors may classify your symptoms based on how much activity you can comfortably undertake. The classes are the same as those for heart failure. They are:

• Class 1: No limits—Ordinary physical activity does not cause undue tiredness or shortness of breath.
• Class 2: Slight or mild limits—Person is comfortable at rest, but ordinary physical activity results in tiredness or shortness of breath.
• Class 3: Marked or noticeable limits—Person is comfortable at rest, but less than ordinary physical activity causes tiredness or shortness of breath.
• Class 4: Severe limits—Person is unable to carry on any physical activity without discomfort. Symptoms may also be present at rest. If any physical activity is undertaken, discomfort increases.

How Is Pulmonary Arterial Hypertension Diagnosed?

There is no one specific test that will show why you have pulmonary arterial hypertension (PAH). Even in its later stages, the signs of the disease are similar to those of other heart and lung conditions.

Your doctor will determine if you have PAH by conducting a series of tests to:

• Determine the pressure in your pulmonary artery
• Find out how well your heart and lungs are working
• Rule out any other conditions that may be causing the hypertension

These tests include:

• Chest x ray. A chest x ray takes a picture of your heart and lungs. It can show if the pulmonary arteries or the right side of the heart are enlarged. It will also help your doctor rule out a number of lung diseases, including chronic obstructive pulmonary disease (COPD), as the cause of your PAH.
• EKG or ECG (electrocardiogram). This test is used to measure the rate and regularity of your heartbeat, as well as the size and position of the right ventricle in your heart. It can help the doctor rule out a number of diseases of the heart.
• Doppler echocardiogram. This test shows whether the right side of your heart is enlarged and how well it is functioning. It is the most reliable noninvasive test for obtaining an estimate of the blood pressure in the pulmonary artery.
• Exercise stress test. Some heart problems are easier to diagnose when the heart is working hard and beating fast. During stress testing, a patient exercises, or is given medicine, to make the heart work harder and beat fast while heart tests are performed. During exercise stress testing, blood pressure and EKG readings are monitored while the patient runs on a treadmill or pedals a bicycle.
  
  In addition to an EKG, other heart tests, such as nuclear heart scanning or echocardiography, can also be done at the same time. During nuclear heart scanning, radioactive dye is injected into the bloodstream, and a special camera shows the flow of blood to the heart muscle. Echocardiography uses sound waves to show blood flow through the chambers and valves of the heart and to show the strength of the heart muscle. If a person is unable to exercise, a medicine can be injected into the bloodstream to make the heart work harder and beat fast. Nuclear heart scanning or echocardiography is then done.
  
  Two newer tests that are being done with stress testing are magnetic resonance imaging (MRI) and positron emission tomography (PET) scanning of the heart. MRI shows detailed images of the structures and beating of the heart. PET scanning shows blood flow to the heart muscle and areas of damaged heart muscle.
• Spirometry (spi-ROM-e-tre). This test measures how well your lungs inhale and exhale air. It is most useful for ruling out obstructive lung diseases like COPD.
• Cardiac catheterisation. This test provides a precise measure of the blood pressure in the right side of your heart and the pulmonary artery. Cardiac catheterisation is the only way to get this measure. It also shows the amount of blood the right ventricle pumps with each heartbeat. This helps your doctor evaluate the pumping ability of the right ventricle. This procedure must be performed in the hospital by a specialist.

Usually, these tests are sufficient to confirm that you have PAH. Sometimes these tests do not rule out all possible causes for the PAH. In that case, your doctor may call for these additional tests:

• Perfusion lung scan. This test shows how the blood is moving in your lungs and whether there are large blood clots that may be causing the PAH.
• Pulmonary arteriography. When the results of a perfusion lung scan do not rule out blood clots in the pulmonary arteries, your doctor may order a pulmonary arteriogram. This test also shows blood clots and other blockages in the blood vessels in the lung.
• Blood tests. Blood tests will rule out HIV, auto-immune diseases like scleroderma, and liver disease.
• Polysomnography (POL-e-som-NOG-ra-fe). This test will help your doctor rule out sleep-disordered breathing as a cause of your PAH.

If these tests do not show an underlying cause for the PAH, the diagnosis is primary pulmonary arterial hypertension.

How Is Pulmonary Arterial Hypertension Treated?

The goals of treatment for patients with pulmonary arterial hypertension (PAH) are to:

• Treat the underlying cause. This is the first priority in patients with secondary pulmonary arterial hypertension (SPAH). Sometimes this treatment can correct the PAH.
• Reduce symptoms and improve quality of life.
• Slow the growth of the smooth muscle cells and the development of blood clots.
• Increase the supply of blood and oxygen to the heart, while reducing its workload.

These treatments include:

• Medicines
• Oxygen
• Lung transplantation

Medicines

• Anticoagulants (AN-te-ko-AG-u-lants) reduce the formation of blood clots.
• Calcium channel blockers relax blood vessels and increase the supply of blood and oxygen to the heart, while reducing its workload. These drugs can be very helpful, but only for a small amount of patients. All patients that take them should be monitored carefully.
• Epoprostenol (e-poe-PROST-en-ole) is a type of medicine called a prostacyclin (pros-ta-SI-klin). It is currently considered the most effective therapy for primary pulmonary arterial hypertension (PPAH). It may also be helpful in treating some forms of severe SPAH. This medication widens the lung arteries and prevents blood clot formation. Until recently, it was given intravenously through a permanent tube, or catheter, placed in a vein in the neck and connected to a battery-powered pump. But in December 2004, a new form of the drug, iloprost, was approved for the treatment of PAH. This medicine can be inhaled through a nebulizer. This makes it more convenient and less painful to take. Plus the medicine goes directly to the lungs, where it is needed.
• Treprostinil, another prostacyclin, also relaxes blood vessels and increases the supply of blood to the lungs, reducing the workload of the heart. It can be given under the skin.
• Bosentan, a relatively new treatment, widens the lung arteries and reduces blood pressure. It also is available in pill form. Until doctors learn more about the long-term effects, all patients taking this drug should be monitored for complications, especially those involving the liver.
• Nitric oxide inhalation, which causes the pulmonary arteries to widen or open, is also being used by some doctors.
• Sildenafil (Viagra®), another drug that causes the pulmonary arteries to open, has recently been shown to improve the condition of PAH patients and is expected to be approved soon. This drug is available in pill form.
• Diuretics (water or fluid pills) may help ease symptoms and improve the heart's performance in some patients with PAH.

Oxygen

You may need oxygen therapy if the level of oxygen in your blood is low. Oxygen is usually given through nasal prongs or a mask. Over time, you may need oxygen around the clock.

Lung Transplantation

Surgery to replace one or both diseased lungs with healthy lungs from a human donor may help some patients. This procedure is usually recommended for patients for whom medical therapy is no longer effective. Complications include rejection by the body of the transplanted lung and infection. Transplant patients must take medicines for life to reduce the chances that their body will reject the transplanted lung.

Other Possible Treatments

Researchers also are studying whether stem cell transplantation combined with gene therapy may provide a cure for PAH in the not too distant future.

Living With Pulmonary Arterial Hypertension

Many people with pulmonary arterial hypertension (PAH) do not look sick. Many feel perfectly well most of the time, as long as they do not strain themselves physically. In the early stages of the disease, many are able to go to school or work on a full- or part-time basis.

Relaxation exercises and stress reduction activities may help many people with PAH keep up with their regular activities for a while. Having a positive attitude is also helpful.

Walking is good exercise for many people with PAH. Advanced patients who find walking too exhausting may use a wheelchair or motorized scooter. Others stay busy with activities that are not of a physical nature.

Some people with advanced PAH carry portable oxygen when they go out.

Ongoing medical care is important. Treatment by a cardiologist or pulmonologist (pull-mon-OL-o-gist) who specializes in pulmonary vascular medicine is usually recommended. These specialists are usually located at major medical centers.

PAH patients should also eat a healthy diet and get plenty of rest, and they should not smoke.

Situations that can make PAH symptoms worse are:

• Living at high altitudes or travelling to high-altitude areas where the air is thin and the amount of oxygen in the air is low
• Air travel
• Pregnancy

Key Points

• Pulmonary arterial hypertension (PAH) is high blood pressure in the pulmonary arteries in the lungs.
• In PAH, the small arteries in the lungs narrow and may eventually become blocked. As a result, the heart must work harder to pump the blood through them. Over time, the overworked heart muscle becomes weak and loses its ability to pump enough blood to the lungs.
• PAH is called primary pulmonary arterial hypertension (PPAH) when no cause can be found for it. Secondary pulmonary arterial hypertension (SPAH) refers to PAH that is caused by or occurs with another condition—usually heart or lung disease.
• Certain factors appear to increase your chances of developing PAH, including use of appetite suppressants or cocaine and the presence of other diseases like HIV infection, scleroderma, and liver disease.
• PPAH may be caused by an abnormality in a gene.
• Common symptoms of PAH include difficulty breathing, fatigue, dizziness, fainting spells, swelling in the ankles or legs, bluish lips and skin, chest pain, and palpitations.
• PAH often is not diagnosed right away because its symptoms are similar to those of other conditions affecting the heart and lungs, and those conditions must be ruled out. Tests that can help confirm a PAH diagnosis include electrocardiogram, Doppler echocardiogram, pulmonary function tests, and cardiac catheterisation.
• Right heart catheterisation is the only way to obtain a precise measure of the blood pressure in the right side of the heart and the pulmonary artery. It is necessary to confirm suspected PPAH.
• Treatments for PAH include anticoagulants, calcium channel blockers, continuous intravenous epoprostenol (prostacyclin and other forms of prostacyclin), new drugs (Bosentan), and sildenafil.
• Surgery to replace one or both diseased lungs with healthy lungs from a human donor can help some people with PAH.
• Relaxation exercises, stress reduction activities, and adoption of a positive attitude can help PAH patients keep up with their normal activities. Eating a healthy diet, getting plenty of rest, and not smoking are also beneficial.
• Ongoing medical care, usually by a cardiologist or pulmonologist who specializes in pulmonary vascular medicine, is important.

Nursing Study #10

Beryllium disease is a condition that can occur from exposure to beryllium dust or fumes. Learn more about beryllium disease including what causes it; how it happens; its symptoms; and how the beryllium lymphocyte proliferation test (BeLPT) is used to help diagnose it.

What is chronic beryllium disease?

Chronic beryllium disease (CBD) is a lung condition that can develop after a person breathes beryllium dust or fumes. The immune system sees beryllium as a “foreign invader,” and builds an “army” of cells in the bloodstream that are prepared to react to beryllium wherever they see it in the body. When an individual is diagnosed with CBD, it generally means the battle between the immune system and the beryllium particles has resulted in scarring (called granulomas) in the lungs.

What are the symptoms of chronic beryllium disease (CBD)?

Individuals with CBD may not have any symptoms at first, especially if the disease is diagnosed at an early stage. Patients may notice shortness of breath with walking, climbing stairs, or another activity, as well as a dry cough that will not go away. Some people may also experience fatigue, night sweats, chest and joint pain, and loss of appetite as the disease progresses.

What can I do to prevent beryllium sensitization and CBD?

The Occupational Safety and Health Administration (OSHA) has set the permissible exposure limit (PEL) for beryllium at 2 micrograms per cubic meter in an 8-hour period. This is roughly equivalent to an amount of beryllium dust the size of a pencil tip spread across an area the length of a football field, 8 feet high. This standard has been shown to be inadequate to prevent beryllium sensitization and CBD ^5,7,8, and many in the beryllium community and at OSHA are currently working to establish a lower limit in the workplace. Because we do not know of a definite “safe” level of exposure below which sensitization and disease do not occur, it is important to limit beryllium exposure to the lowest level possible. In the workplace, you should substitute another product for beryllium if at all possible, avoid dry sweeping of work areas, use proper exhaust ventilation and equipment, minimize the number of individuals who have access to areas where beryllium is used, ensure respirators fit properly and are used appropriately, change clothes before leaving the beryllium area and work facility, and ensure employees receive regular training on the proper handling of beryllium, as well as the hazards of beryllium exposure.

Source:
http://www.nationaljewish.org/disease-info/diseases/occ-med/beryllium/about/sensitization/about.aspx#what

Nursing Study #9

Asthma (Az-muh) is a chronic disease that affects your airways. The airways are the tubes that carry air in and out of your lungs. If you have asthma, the inside walls of your airways are inflamed (swollen). The inflammation (IN-fla-MAY-shun) makes the airways very sensitive, and they tend to react strongly to things that you are allergic to or find irritating. When the airways react, they get narrower, and less air flows through to your lung tissue. This causes symptoms like wheezing (a whistling sound when you breathe), coughing, chest tightness, and trouble breathing, especially at night and in the early morning.

Asthma cannot be cured, but most people with asthma can control it so that they have few and infrequent symptoms and can live active lives.

When your asthma symptoms become worse than usual, it is called an asthma episode or attack. During an asthma attack, muscles around the airways tighten up, making the airways narrower so less air flows through. Inflammation increases, and the airways become more swollen and even narrower. Cells in the airways may also make more mucus than usual. This extra mucus also narrows the airways. These changes make it harder to breathe.

Asthma attacks are not all the same—some are worse than others. In a severe asthma attack, the airways can close so much that not enough oxygen gets to vital organs. This condition is a medical emergency. People can die from severe asthma attacks.

So, if you have asthma, you should see your doctor regularly. You will need to learn what things cause your asthma symptoms and how to avoid them. Your doctor will also prescribe medicines to keep your asthma under control.

Taking care of your asthma is an important part of your life. Controlling it means working closely with your doctor to learn what to do, staying away from things that bother your airways, taking medicines as directed by your doctor, and monitoring your asthma so that you can respond quickly to signs of an attack. By controlling your asthma every day, you can prevent serious symptoms and take part in all activities.

If your asthma is not well controlled, you are likely to have symptoms that can make you miss school or work and keep you from doing things you enjoy. Asthma is one of the leading causes of children missing school.

Source:
http://www.nhlbi.nih.gov/health/dci/Diseases/Asthma/Asthma_WhatIs.html

Nursing Study #8

Pneumonia is a lung disease. Pneumococcal pneumonia can infect the upper respiratory tract and can spread to the blood, lungs, middle ear, or nervous system.

Pneumococcal pneumonia mainly causes illness in children younger than 2 years old and adults 65 years of age or older. The elderly are especially at risk of getting seriously ill and dying from this disease. In addition, people with certain medical conditions such as chronic heart, lung, or liver diseases or sickle cell anemia are also at increased risk for getting pneumococcal pneumonia. People with HIV infection, AIDS, or people who have had organ transplants and are taking medicines that lower their resistance to infection are also at high risk of getting this

Cause

Pneumonia can be caused by a variety of viruses, bacteria, and sometimes fungi. Pneumococcal pneumonia is caused by bacteria called Streptococcus pneumoniae. S. pneumoniae is also called pneumococcus.

Transmission

Pneumococcus is spread through contact between people who are ill or who carry the bacteria in their throat. You can get pneumococcal pneumonia from respiratory droplets from the nose or mouth of an infected person. It is common for people, especially children, to carry the bacteria in their throats without being sick.

Symptoms

Pneumococcal pneumonia may begin suddenly. You may first have a severe shaking chill which is usually followed by

• High fever
• Cough
• Shortness of breath
• Rapid breathing
• Chest pains

Other symptoms may include

• Nausea
• Vomiting
• Headache
• Tiredness
• Muscle aches

Diagnosis

Your health care provider can diagnose pneumonia based on your

• Symptoms
• Physical exam
• Lab tests
• Chest x-ray

Other bacteria and germs also can cause pneumonia. Therefore, if you have any of the symptoms of pneumonia, you should get diagnosed early and start taking medicine, if appropriate.

Your health care provider can usually diagnose pneumococcal pneumonia by finding S. pneumoniae bacteria in your blood, saliva, or lung fluid.

Treatment

Your health care provider usually will prescribe antibiotics to treat this disease. The symptoms of pneumococcal pneumonia usually go away within 12 to 36 hours after you start taking medicine.

Some bacteria such as S. pneumoniae, however, are now capable of resisting and fighting off antibiotics. Such antibiotic resistance is increasing worldwide because these medicines have been overused or misused. Therefore, if you are at risk of getting pneumococcal pneumonia, you should talk with your health care provider about what you can do to prevent it.

Prevention

The pneumococcal vaccine is the only way to prevent getting pneumococcal pneumonia. Vaccines are available for children and adults.

The Vaccines and Immunizations of the Centers for Disease Control and Prevention recommends that you get the pneumococcal pneumonia vaccine if you are in any of the following groups.

• You are 65 years old or older
• You have a serious long-term health problem such as heart disease, sickle cell disease, alcoholism, lung disease (not including asthma), diabetes, or liver cirrhosis
• Your resistance to infection is lowered due to
• HIV infection or AIDS
• Lymphoma, leukemia, or other cancers
• Cancer treatment with x-rays or medicines
• Treatment with long-term steroid medicines
• Bone marrow or organ transplant
• Kidney failure or kidney syndrome
• Damaged spleen or no spleen
• You are an Alaskan Native or from certain Native American populations

NIP also recommends that all babies and children younger than 2 years old get the pneumococcal vaccine.

Contact your health care provider to find out whether you or your child should be vaccinated to prevent pneumococcal pneumonia.

Complications

In about 30 percent of people with pneumococcal pneumonia, the bacteria invade the bloodstream from the lungs. This causes bacteremia, a very serious complication of pneumococcal pneumonia that also can cause other lung problems and certain heart problems.

Source:
http://www3.niaid.nih.gov/topics/pneumonia/

Nursing Study #7

Cystic fibrosis (CF) is an inherited disease of your mucus and sweat glands. It affects mostly your lungs, pancreas, liver, intestines, sinuses, and sex organs.

Normally, mucus is watery. It keeps the linings of certain organs moist and prevents them from drying out or getting infected. But in CF, an abnormal gene causes mucus to become thick and sticky.

The mucus builds up in your lungs and blocks the airways. This makes it easy for bacteria to grow and leads to repeated serious lung infections. Over time, these infections can cause serious damage to your lungs.

The thick, sticky mucus can also block tubes, or ducts, in your pancreas. As a result, digestive enzymes that are produced by your pancreas cannot reach your small intestine. These enzymes help break down the food that you eat. Without them, your intestines cannot absorb fats and proteins fully.

As a result:

• Nutrients leave your body unused, and you can become malnourished.
• Your stools become bulky.
• You may not get enough vitamins A, D, E, and K.
• You may have intestinal gas, a swollen belly, and pain or discomfort.

The abnormal gene also causes your sweat to become extremely salty. As a result, when you perspire, your body loses large amounts of salt. This can upset the balance of minerals in your blood. The imbalance may cause you to have a heat emergency.

CF can also cause infertility (mostly in men).

The symptoms and severity of CF vary from person to person. Some people with CF have serious lung and digestive problems. Other people have more mild disease that doesn't show up until they are adolescents or young adults.

Respiratory failure is the most common cause of death in people with CF.

Until the 1980s, most deaths from CF occurred in children and teenagers. Today, with improved treatments, people with CF live, on average, to be more than 35 years old. Research continues to look for:

• Better treatments
• A cure

Source:
http://www.nhlbi.nih.gov/health/dci/Diseases/cf/cf_what.html

Nursing Study #6

Chronic obstructive pulmonary disease (COPD) is a lung disease in which the lungs are damaged, making it hard to breathe. In COPD, the airways—the tubes that carry air in and out of your lungs—are partly obstructed, making it difficult to get air in and out.

Cigarette smoking is the most common cause of COPD. Most people with COPD are smokers or former smokers. Breathing in other kinds of lung irritants, like pollution, dust, or chemicals, over a long period of time may also cause or contribute to COPD.

The airways branch out like an upside-down tree, and at the end of each branch are many small, balloon-like air sacs. In healthy people, each airway is clear and open. The air sacs are small and dainty, and both the airways and air sacs are elastic and springy. When you breathe in, each air sac fills up with air like a small balloon; when you breathe out, the balloon deflates and the air goes out. In COPD, the airways and air sacs lose their shape and become floppy. Less air gets in and less air goes out because:

• The airways and air sacs lose their elasticity (like an old rubber band).
• The walls between many of the air sacs are destroyed.
• The walls of the airways become thick and inflamed (swollen).
• Cells in the airways make more mucus (sputum) than usual, which tends to clog the airways.

COPD develops slowly, and it may be many years before you notice symptoms like feeling short of breath. Most of the time, COPD is diagnosed in middle-aged or older people.

COPD is a major cause of death and illness, and it is the fourth leading cause of death in the United States and throughout the world.

There is no cure for COPD. The damage to your airways and lungs cannot be reversed, but there are things you can do to feel better and slow the damage.

COPD is not contagious—you cannot catch it from someone else.

Other Names for COPD

• Chronic obstructive airway disease
• Chronic obstructive lung disease

In the United States, chronic obstructive pulmonary disease (COPD) includes:

• Emphysema
• Chronic bronchitis

In the emphysema type of COPD, the walls between many of the air sacs are destroyed, leading to a few large air sacs instead of many tiny ones. Consequently, the lung looks like a sponge with many large bubbles or holes in it, instead of a sponge with very tiny holes. The large air sacs have less surface area for the exchange of oxygen and carbon dioxide than healthy air sacs. Poor exchange of the oxygen and carbon dioxide causes shortness of breath.

In chronic bronchitis, the airways have become inflamed and thickened, and there is an increase in the number and size of mucus-producing cells. This results in excessive mucus production, which in turn contributes to cough and difficulty getting air in and out of the lungs.

Most people with COPD have both chronic bronchitis and emphysema.

Source:
http://www.medic8.com/lung-disorders/copd.htm

Nursing Study #5

Lungs are the organs that allow us to breathe. Lungs provide a huge area (as large as a football field) for oxygen from the air to pass into the bloodstream and carbon dioxide to move out. The cells of our bodies need oxygen in order to work and grow. Our cells also need to get rid of carbon dioxide.

During a normal day, we breathe nearly 25,000 times, and take in (inhale) large amounts of air. The air we take in contains mostly oxygen and nitrogen. But air also has things in it that can hurt our lungs.Bacteria, viruses, tobacco smoke, car exhaust, and other pollutants can be in the air. People with lung disease have difficulty breathing. These breathing problems may prevent the body from getting enough oxygen.

Source:
http://www.womenshealth.gov/faq/lung_disease.htm

Nursing Study #4
a simple explanation about Tuberculosis

What is TB?
Tuberculosis (TB) is a disease caused by germs that are spread from person to person through the air. TB usually affects the lungs, but it can also affect other parts of the body, such as the brain, the kidneys, or the spine. A person with TB can die if they do not get treatment.

What Are the Symptoms of TB?
The general symptoms of TB disease include feelings of sickness or weakness, weight loss, fever, and night sweats. The symptoms of TB disease of the lungs also include coughing, chest pain, and the coughing up of blood. Symptoms of TB disease in other parts of the body depend on the area affected.

How is TB Spread?
TB germs are put into the air when a person with TB disease of the lungs or throat coughs, sneezes, speaks, or sings. These germs can stay in the air for several hours, depending on the environment. Persons who breathe in the air containing these TB germs can become infected; this is called latent TB infection.

How is TB Disease Treated?
TB disease can be treated by taking several drugs for 6 to 12 months. It is very important that people who have TB disease finish the medicine, and take the drugs exactly as prescribed. If they stop taking the drugs too soon, they can become sick again; if they do not take the drugs correctly, the germs that are still alive may become resistant to those drugs. TB that is resistant to drugs is harder and more expensive to treat. In some situations, staff of the local health department meet regularly with patients who have TB to watch them take their medications. This is called directly observed therapy (DOT). DOT helps the patient complete treatment in the least amount of time.

Source:
http://www.cdc.gov/tb/pubs/tbfactsheets/tb.htm

Nursing Study #3

Any substance that is breathed in affects what happens to the lungs. Many of these substances can be hazardous and threaten the lungs' ability to work properly. Such hazards may include:

• 1. Cigarette Smoking - The major cause of chronic obstructive pulmonary disease (COPD) and lung cancer is cigarette smoking. When someone inhales cigarette smoke, irritating gases and particles cause one of the
  lungs' defenses - the cilia - to slow down. Even one puff on a cigarette slows the cilia, weakening the lungs' ability to defend themselves against infections. Cigarette smoke can cause air passages to close up and make breathing more difficult. It causes chronic inflammation or swelling in the lungs, leading to chronic bronchitis. And cigarette smoke changes the enzyme balance of the lungs, leading to destruction of lung tissue that occurs in emphysema. Macrophages-scavenger cells in the lung-are also harmed.
• 2. Triggers of Asthma - Asthma, the temporary blocking of the small air passages of the lungs, has many possible triggers and can be life-threatening. Infections, lung irritants, cold weather, allergies, over-exertion, excitement, inherited factors, even workplace chemicals and other irritants play a part in this disease.
• 3. Tuberculosis (TB) - Tuberculosis is caused by a bacterium spread by the coughing or sneezing of a person who has active TB germs in his or her mucus (sputum). Many people who develop TB today were infected years ago when the disease was more widespread.
  
  Years or decades later, if the natural defense systems of people's bodies begin to weaken, the barriers they built up around the germs begin to crumble, and the TB germs escape and multiply. Such latent (waiting-to-attack) infection can become real illness when a person's defenses are weakened by HIV (Human Immunodeficiency Virus) infection or other chronic illnesses such as cancer.
  
  A related problem is that outbreaks of TB involving newly infected people are becoming more common in high-risk populations. These groups include individuals who have limited access to health care. In fact, worldwide, TB has become a major international health concern.
• 4. Occupational Hazards - Substances you breathe at work can cause lung disease, too.
  Workers who are exposed to occupational hazards in the air - dusts like those from coal, silica, asbestos, or raw cotton and metal fumes or chemical vapors-can develop lung disease, including occupational asthma.
• 5. , Virus, Fungus, Bacterium (other than TB)Hundreds of germs like these are carried in the air at all times. If they are inhaled into the lungs, the germs can cause colds, influenza, pneumonia, and other respiratory infections. When these germs lodge in your lungs, your breathing can be disrupted and you can become ill. Some of these illnesses can be prevented with vaccination.
• 6. Air Pollution - Particles and gases in the air can be a source of lung irritation. Do whatever you can to reduce your exposure to air pollution. Refer to radio or television weather reports or your local newspaper for information about air quality. On days when the ozone (smog) level is unhealthy, restrict your physical activity to early morning or evening because smog is increased in sunlight. When pollution levels are dangerous, limit activities as necessary. People with chronic heart and lung disease should remain indoors.
• Air pollution can be a problem indoors, too. Check your home for irritants that you can control like dust, household chemicals, and cigarette smoke. You may also want to test your home for the presence of the gas, radon, which is the second leading cause of lung cancer.

Source:
http://www.smokehelp.org/html/lung_disease.html

Nursing Study #2

Cough
Coughing is a defense mechanism that is used to clear the airways of mucus, inhale toxins, or a foreign body. Coughs can be productive or unproductive depending on how it is done. A productive cough should result in the clearing of mucus or secretions from the airways. A persistent or worsening cough hay be accompanied by a high fever, dyspnea, or bloody or copious sputum requiring immediate medical attention. Coughing is one of the most common lung disease symptoms.

Chronic Mucus Production
Mucus, or sputum, is produced by the lungs as a defense response to infection or irritants. If your mucus production has lasted a month, this could indicate lung disease.

Dyspnea
Dyspnea (shortness of breath) is sometimes a result of a problem with the respiratory system, heart disease, anxiety, or other condition. Sudden bouts of shortness of breath, particularly if is is persistent or accompanied by other symptoms, may indicate disease, and should be evaluated by a doctor immediately. Shortness of breath is NOT a natural part of aging. It should be taken seriously and reported to your doctor.

Wheezing
Wheezing is a high pitched sound produced while inhaling or exhaling. It occurs when airways are narrowed or obstructed by abnormal tissue or inflammation, excessive secretions or mucus, or when a foreign material has been inhaled and is obstructing the airways. Wheezing may also be a signal that a lung condition is worsening.

Lung Disease Symptoms - Chest Pain
Chest pain generally indicates a problem in the lungs, pleura, or muscles and bones of the chest wall. The problem may be minor or severe, or even life-threatening, and may be constant or experienced only during inhalation. Pain in the chest may indicate infection if it is accompanied by cough or fever. If you are experiencing chest pain, you should immediately seek medical attention.

Lung Disease Symptoms - Hemoptysis
Hemoptysis (coughing up blood) may appear as pinkish froth, mucus with a bloody streak or clot, or pure blood. It may occur as a result of a persistent cough or it may be indicative of a serious lung disease. If you are experiencing hemoptysis, you should consult your doctor immediately. Hemoptysis is a serious lung disease symptom.

Lung Disease Signs - Cyanosis
Cyanosis is when the skin becomes a bluish or purplish color, most apparent around the lips and nail beds. It is a sign that the blood is not receiving enough oxygen. Cyanosis may appear suddenly as a result of acute lung disease or slowly as lung disease progressively worsens.

Lung Disease Signs - Swelling
Swelling of the arms, legs, and ankles may indicate lung disease. Swelling is typically associated with heart disease and accompanied by shortness of breath. Many times, the heart and lungs produce similar symptoms because many disorders affect both organs. (Read: Why Does Lung Disease Cause Swollen Ankles?)

Lung Disease Symptoms - Respiratory Failure
Respiratory failure is the most severe sign of lung disease, acute and chronic. Acute respiratory failure may be due to massive infection, lung inflammation, cessation of the heartbeat, or severe lung disease. Chronic respiratory failure is when the lungs cannot oxygenate the blood and/or remove carbon dioxide normally.

Sources:
http://lungdiseases.about.com/od/generalinformation1/a/signsoflungdis.htm
http://www.smokehelp.org/html/lung_disease.html

Nursing Study #1

Does nicotine have a strong hold over you? It’s one of the most addictives substances on the planet - found naturally in tobacco. Although not illegal, it’s equally as addictive as cocaine or heroine, two illegal drugs known for their strong addictive qualities.

When you use nicotine, your body begins to rely on it both mentally and physically. You can’t quit smoking because you have to face both the psychological and physical issues facing you at this point, which is often overwhelming for anyone.

It’s not the smoke itself that wreaks havoc on your addictions and makes it nearly impossible for you to quit smoking – it’s the nicotine that gets carried in the smoke deep into your lungs where it plants itself in your bloodstream and then moves to every available part of your body to affect your internal health.

Your heart and blood vessels, your brain, your hormones, and your metabolism are all directly affected by nicotine. Even though you may logically know the damage being done, your ability to quit smoking is diminished because the drug has the same effect as endorphins, releasing mood-elevating feelings that cause you to crave more.

But nicotine has another result. When you try to quit smoking, or even stay at the same number of cigarettes you currently smoke, your body triggers you to smoke more, telling you that you’ve become tolerant of your current usage. Nicotine can cause your body to react faster than if you were given a drug intravenously.

If you are able to quit smoking, nicotine will still reside in your body for up to four days after you stop using it. Your body will go into withdrawal, which is both a mental and physical obstacle you have to overcome.

While the physical portion of the addiction has to be dealt with through symptoms such as sleep disturbance, headaches, and dizziness, when someone quits smoking, the mental portion is noticeable when the newly ex-smoker starts dealing with depression, frustration, and anger that results from nicotine withdrawal.

Because of the pressure felt in both the mind and body, many smokers return to the bad habit so that the nicotine will erase the symptoms they’re feeling. The dilemma of withdrawal symptoms when someone quits smoking can last for days or weeks, depending on the severity of the addiction.

Eventually, the symptoms disappear and the strong hold nicotine has over the user loosens up its grip and allows the ex-smoker to break the habit for good. Most smokers have to try several times before they’re able to quit smoking forever, although many do it on the first try using smoking cessation aids.