|
|||||||
|
|
||||||||||||||||||||||||||||||||||||||||||
The basic function of the lungs is to take oxygen out of the air we breathe in exchange for the carbon dioxide dissolved in the blood. This exchange takes place across a very thin membrane that separates the blood in the lungs from the air we inhale. As we age, the lungs become stiffer and less elastic, the airways shrink, and the chest muscles weaken. These and other changes cause the total flow of air into and out of the lungs to decrease. Cigarette smoking, air pollution, and previous occupational exposures to hazards (eg, soot or asbestos) also have a negative effect on lung health. Other illnesses also affect lung health. For example, heart failure often causes fluid to back up into the lungs, causing poor air exchange and difficulty breathing. All together, these changes and conditions increase the chances of developing breathing problems as we age.
Common SymptomsWe all have respiratory symptoms from time to time, such as occasional coughing from a cold or flu. Because these symptoms are so common, we sometimes ignore them, even when they persist and begin to interfere with daily activities. This is especially true for older adults, who tend to downplay the importance of chronic coughing or a breathing problem until it becomes serious. We often tend to think these problems are simply caused by being old, overweight, or out of shape. We also tend to adjust our lifestyle and activity level to make up for less ability to exercise, often without thinking about it. For example, we may cut down on walking to the store or on performing self-care activities downstairs instead of upstairs. Not being able to exercise as much and the other changes in lifestyle described above are usually caused by underlying heart (see Disorders of the Heart and Circulatory System) or respiratory problems. Severe or frequent coughing, wheezing, or being out of breath are early warning signs of a potentially serious problem. Coughing is part of the body’s normal respiratory defenses. Short bouts of coughing are usually caused by mild respiratory infections (eg, colds). Coughs that last more than 3–4 weeks should be evaluated. One of the most common causes of persistent cough is cigarette smoking, which irritates the airways and can lead to emphysema or lung cancer. Unfortunately, older smokers become used to this cough and tend not to seek medical attention for it. In nonsmokers, 90% of persistent coughs are caused by mild respiratory problems, such as postnasal drip, asthma, or heartburn. Persistent cough has also been linked to certain medications widely used for treating high blood pressure or heart failure. Early medical attention for persistent cough is important, because early diagnosis and treatment can keep a mild problem from becoming serious. Sometimes, the underlying problem is much more serious (eg, cancer, pneumonia, or heart failure), again warranting medical evaluation. The air we breathe passes through flexible airways that get smaller and smaller on their way to the air sacs of the lungs (Figure: The Lungs and Chronic Lung Problems). Muscles in the thin walls of these airways contract when they are irritated, making it more difficult to breathe out. When we try to force air through these narrower airways, we wheeze. The muscles in the airways spasm, which temporarily blocks airflow. Asthma and post-nasal drip are common causes of wheezing in all age groups. Inflammation of the larger airways (bronchitis) is also a common cause of wheezing, especially in smokers. In older adults, heart failure is also a common cause when fluid backs up into the lungs from the circulation (see also Disorders of the Heart and Circulatory System). This latter condition is sometimes called “cardiac asthma,” because people may have symptoms resembling asthma, including wheezing, chest tightness, sweating, and a gray complexion. All of the above conditions can be potentially serious in older adults, and medical evaluation is needed. Difficult or labored breathing refers to shortness of breath after only a small amount of activity. Depending on the underlying problem, this can range from being out of breath after mild exercise to being unable to get out of a chair without gasping for air. Labored breathing is often accompanied by cough, wheeze, or other symptoms, depending on the underlying problem. Common causes in older adults include heart disease, asthma, obesity, and lung problems, including chronic obstructive pulmonary disease (COPD). The term COPD covers any lung problem that makes it difficult to breathe out or exhale, including asthma and emphysema. The diagnosis and treatment of persistent respiratory symptoms depends on the underlying problem. Your healthcare provider will ask about your symptoms, review your current medications, and perform a physical examination. This may suggest a treatment that can be tried to see if it resolves the problem. For example, otherwise healthy people with a persistent cough might first be prescribed medication to control asthma or post-nasal drip, depending on their history and physical examination. If the condition does not improve or worsens, further diagnostic tests may be necessary, such as x-rays, bacterial culture of the sputum, an electrocardiogram (ECG), examination of the airways (by endoscopy), or sophisticated breathing studies. Major Breathing Disorders in Older Adults See also Cancer for a discussion of lung cancer, and Infectious Illness for discussions of pneumonia and tuberculosis. Chronic obstructive pulmonary disease (COPD) Breathing problems that involve difficulty in exhaling or breathing air out of the lungs are referred to as chronic obstructive pulmonary disease (COPD). Common examples of COPD include emphysema and chronic bronchitis. In emphysema, the small air spaces in the lungs collapse, leaving holes in the lungs like Swiss cheese (Figure: The Lungs and Chronic Lung Problems). In bronchitis, inflammation of the airways causes phlegm buildup and scarring over time. This makes it more difficult to breathe and increases the chance of infection. Typically, people with chronic bronchitis cough up mucus or phlegm every day for months to years. Cigarette smoking is the most common cause of chronic bronchitis, although genetics and exposure to hazardous substances in various occupations also play a role. Distinguishing between specific conditions that cause COPD can be difficult in older adults. For example, the signs and symptoms of asthma are often hard to distinguish from the less treatable disorders of emphysema and chronic bronchitis. In addition, many older adults have a combination of emphysema and chronic bronchitis. People with COPD usually become short of breath on exertion and cough frequently, bringing up phlegm. These symptoms develop gradually over time, so that breathing problems may not be noticed until another illness (eg, flu) adds to the burden on the respiratory system. Sometimes people with COPD develop a large “barrel-shaped” chest because the body has difficulty emptying air from the lungs. Diagnosis: Your healthcare provider can usually get a good idea about possible COPD from your history and physical examination. For example, smokers with a history of chronic wheezing and phlegm production usually have COPD. Other signs that suggest COPD include a barrel-shaped chest and a very resonant sound when the chest is thumped on physical examination. However, lung function tests are often used to confirm a diagnosis of COPD. The simplest and most useful lung function test is called a spirogram. The spirogram measures the amount of air in the lungs and the rate at which the lungs empty as a person breathes into the machine. Other tests that may be useful include chest x-rays and blood samples to determine the amount of oxygen, carbon dioxide, and acid in the blood. Treatment: The goal of treatment for COPD is to maintain independent function, while preventing infection and more lung injury. The most important step is quitting smoking. Quitting at any age slows down the loss of lung function. Drug treatment can make breathing easier and can reduce wheezing, cough, and phlegm. The main drugs used to treat COPD include the class of drugs known as beta-agonists and another drug called ipratropium bromide. Beta-agonists and ipratropium are often used in combination and are inhaled to help expand the airways. Pulmonary rehabilitation in the form of exercise training, respiratory therapy, and education may also help people with COPD. Exercise has many health benefits, including reducing depression and anxiety. Clinical depression (see Depression) and anxiety (see Anxiety Disorders) are common problems for people with COPD. Anxiety attacks often result in hospitalization that can be possibly avoided with proper treatment and education. Asthma is common in children and young adults and can affect 10% of older adults over age 65. Most asthma is caused by respiratory allergy to particles in the air, such as indoor molds and house dust. The airways become inflamed and irritated, which causes them to spasm, making it difficult to breathe (especially to exhale). This produces a feeling of tightness in the chest and a characteristic wheeze. Asthma episodes can also be triggered by general respiratory irritants, such as tobacco smoke, air pollution, and even cold air or exercise. Asthma differs from COPD because it is reversible. Spasms usually quiet down after a few minutes, and breathing becomes normal again. However, each asthma attack can cause considerable discomfort and a feeling of panic from not being able to catch your breath. Asthma attacks can also occasionally lead to life-threatening breathing problems. In addition, frequent asthma attacks make the airways smaller and less elastic, which leads to breathing problems that are not reversible. Diagnosis: A tentative diagnosis of asthma can be based on a characteristic history of episodes of wheezing. However, making sure the problem is asthma requires knowing that the breathing difficulty can be reversed. This usually means running a “spirogram” before and after inhaling medication that opens up the airways. A spirogram is a breathing test that measures how well air moves out of the lungs. A large improvement in the spirogram test indicates that the airways are responding to the medication, and that the problem is asthma. Another diagnostic approach involves actually trying to bring on an asthma attack by inhaling a substance that constricts the airways. A large drop in lung function shows that the airways are constricting, again suggesting asthma. This latter test is done only in otherwise healthy people who do not have asthma attacks that are severe. Treatment: Two types of inhaled drugs form the mainstay of asthma treatment in older adults. Corticosteroids decrease the inflammation and prevent frequent asthma attacks. Corticosteroids that are inhaled have fewer serious side effects than when taken orally or injected. However, it is still important to inhale the lowest dose that prevents attacks to keep the potential for side effects at a minimum. You should also rinse your mouth after inhaling a corticosteroid product to prevent oral fungal infections (thrush). “Rescue” inhalers are used to relieve symptoms of an asthma attack. These inhalers usually contain drugs called beta-agonists, which open up the airways by relaxing the muscles in the airway walls. Rescue inhalers should be used only when needed to minimize potential side effects and lessen the chance of becoming too dependent on these drugs. Possible side effects include low blood potassium and interaction with other drugs (eg, digitalis). Metered-dose inhalers take some getting used to and require practice to use properly. A certain amount of manual dexterity (use of the hands and fingers) is needed, which may be limited in older adults with arthritis, muscle problems, or nerve problems. It is a good idea to have your healthcare provider watch as you use the inhaler to make sure you are using it correctly. Your pharmacist can also instruct you on proper use. Breathing problems related to sleep are very common in older adults. The most common problem is obstructive sleep apnea, in which someone stops breathing for brief periods during the night. Obstructive sleep apnea is usually caused when tissue in the back of the throat collapses and blocks the airway during sleep. Usually, the person snores heavily. Often, people fall back to sleep quickly and are not even aware that they stopped breathing and woke up. Sleep apnea results in less restful sleep and has been linked to serious health effects, including stroke, heart problems, and death. Risk factors include the following:
Many people with obstructive sleep apnea are never diagnosed. Although your history may suggest sleep apnea, diagnosis and treatment may require going to a sleep clinic or specialist. It is a good idea to check with your health insurance company before visiting a sleep specialist, because diagnosis and treatment of sleep apnea is not always covered. Some simple approaches can sometimes help correct sleep apnea. These include losing weight, avoiding alcohol and sedatives, sleeping on your side or propped upright, and correcting metabolic disorders (eg, underactive thyroid). However, people often need a treatment called continuous positive airway pressure (CPAP) to control sleep apnea. While you sleep, CPAP delivers continuous air pressure to your airways through a nasal mask. This may take some getting used to, but it can greatly improve the quality of your sleep over time. In pulmonary fibrosis, there is scarring of the lungs. The air sacs become filled with scar tissue. This causes them to thicken so that they are less able to give oxygen to the blood. The damage is not reversible. Common symptoms include shortness of breath, weakness, chronic dry cough, chest discomfort, loss of appetite, and loss of weight. Symptoms usually begin gradually, but always progress. Pulmonary fibrosis usually begins in people who are 40–60 years old but can develop at any age. The causes are not fully known but may include genetics (inherited), autoimmune processes (ie, the body’s own defenses attack the lungs), or chronic injury to the lungs (eg, exposure to asbestos on the job). Diagnosis is based on history, physical examination, and specialized tests such as lung function tests (eg, spirograms), blood gas (eg, oxygen) measurements, “lung washes,” and lung biopsy. There is currently no cure. Initial treatment often consists of oral corticosteroids for 3–6 months, but unfortunately, a good response is seen in only 10%–20% of cases. In addition, adverse side effects from corticosteroids are common and sometimes severe. Supplemental oxygen is usually helpful. Medications to treat possible autoimmune processes or experimental therapies may help some people. Early referral to a lung specialist is important. In pulmonary thromboembolism, a blood clot from somewhere else in the circulation (eg, usually a leg vein) travels to the lung and suddenly blocks blood flow, which damages a section of lung tissue. This can be life threatening. Pulmonary thromboembolism is most common after age 65 and comes back within 1 year in about 10% of people. Risk factors include the following:
Along with history and physical examination, specialized imaging studies (such as CAT scans, angiography, etc) are usually needed to confirm the diagnosis. Treatment involves thinning the blood with anticoagulants. Usually, intravenous or subcutaneous heparin is followed by warfarin (or another oral blood thinner) for at least 6 months. People with multiple risk factors are often treated for 2 years or longer to help prevent the condition from coming back. Side effects from blood thinners include bleeding from stomach ulcers, nose bleeds, and slow wound clotting. Blood thinners can also cause interact with other medications commonly given to older adults (eg, anti-inflammatory drugs). Aspiration of liquid or other materials from the mouth into the airways can be a serious problem. Substances such as bacteria in the mouth, vomit, or food material can irritate the air passages, which may progress to pneumonia (see Infectious Illness). Everyone occasionally aspirates small amounts of saliva and oral bacteria (ie, something goes down the wrong “pipe”), but the immune system usually prevents infection. Serious lung infection results when the amount of aspirated material is too great for the immune system to handle, or when the body is already weaker than normal. Symptoms can be subtle but may include rapid breathing, fever, wheezing, or breathing that is more difficult at night (aspiration is more common while lying down). Important risk factors include the following:
Treatment for aspiration is aimed at the underlying pneumonia (see Infectious Illness). Of course, prevention is the best. Measures to prevent aspiration include keeping the head and shoulders slightly elevated at all times (especially at night) and minimizing drugs that decrease the level of consciousness (eg, alcohol, antihistamines, or sedatives). Proper oral and dental care is also important to minimize the bacteria living in the mouth that can be potentially aspirated. |
|
|||||||||||||||||||||||||||||||||||||||||
;){kind=link}
Published: 8/5/2005