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Introduction

You may take breathing for granted, thinking that it is just an involuntary reflex action. But for the millions of people who suffer from respiratory diseases, each breath is a major accomplishment. Those people include patients with chronic lung problems, such as asthma, bronchitis, and emphysema, but they also include heart attack and accident victims, premature infants, and people with cystic fibrosis, lung cancer, or AIDS. In this booklet, however, we propose to discuss some of the common respiratory diseases.

The human respiratory system not only provides oxygen to each cell of the body but also removes body wastes, filters out infectious agents, and provides air needed for speech. Although the lungs are able to with stand abuse in the form of smoke and other pollutants, a number of disorders impair its function. Some of these maladies are temporary and relatively harmless; others may be life-threatening. Any chronic breathing problem or other cough should be checked promptly. Take care of your lungs and they will take care of you.

The information in this booklet is not intended as medical advice – the doctor knows best. This booklet only intends to help patients make informed decisions.

Common Cold
What we call the common cold is actually a set of symptoms of upper respiratory infection caused by a wide range of infectious viruses. Symptoms include watery nasal discharge, sneezing, stuffiness, sore throat, fatigue, muscle aches and headache, and – occasionally – fever. If the doctor suspects a cold, he will look out for inflamed nasal lining, a swollen turbinate, clear mucus or a red throat. In any case, call him if your fever fails to subside in 48 to 72 hours or if it exceeds 102 degrees F.

Because of the large number of viruses that can cause viral rhinitis, it is impossible for the body to develop immunity against a cold. The body may become immune to a particular virus. However, another one may come along producing the same symptoms. That is also the reason why no preventive vaccine has been developed for the common cold.

Colds do not arise because you become chilled or wet. The viruses that cause colds pass from person to person, usually through body contact with nasal secretions or because viruses come into contact with nasal secretions or branes. A cold usually takes 7 to 10 days to subside.

Over the counter decongestant medications and acetaminophen can temporarily reduce the symptoms of a cold. Recent studies suggest that the zinc, taken in the form of lozenges three or four times a day, may help reduce the length of the cold. However, these studies are inconclusive. Prevention, therefore, is the best defence against colds. Except for symptomatic treatments, there is no effective medical therapy for colds.

Asthma

Perhaps the most commonly discussed respiratory disease after the common cold is asthma. The word asthma is derived from a Greek work meaning “breathlessness” or “panting”, both of which accurately describe an asthma attack. It is, however, not just another “breathing problem”. To physicians who treat asthma, it is a serious medical condition” untreated asthma can be fatal.

Asthma is a condition in which the airways of the lungs become either narrowed or completely blocked, obstructing normal breathing. This obstruction of the lungs, however, is reversible, either spontaneously or with medication. That is why asthma is technically called Reversible Obstructive Airway Disease (ROAD)

Air reaches the lung through the windpipe (trachea), which divides into two large tubes (bronchi), one for each lung. Each bronchi further divides into many little tubes (bronchioles), which eventually lead to tiny air sacs (alveoli), in which oxygen from the air is transferred to the bloodstream, and carbon dioxide from the bloodstream is transferred to the air.

Although everyone’s airways have the potential for constricting in response to allergens or irritants, the asthmatic’s airways may become obstructed by constriction of the muscles surrounding the airway or inflammation and swelling of the airway or increased mucus production which clogs the airway.

Once the airways have become obstructed, it takes more effort to force air through them and breathing becomes laboured. This forcing of air through constricted airways can make a whistling sound, called wheezing. Irritation of the airways by excessive mucus may also provoke coughing.

Because exhaling through the obstructed airways is difficult, too much stale air remains in the lungs after each breath. This decreases the amount of fresh air which can be taken in with each new breath, so not only is there less oxygen available for the whole body, but more importantly, the high concentration of carbon dioxide in the lungs causes the blood supply to become acidic. This acidity in the blood may rice to toxic levels if the asthma remains untreated.

Asthma episodes can be triggered by a variety of factors, most notably allergens, infections, environmental pollutants, and nonspecific stimuli such as exercise and emotional states.

Anatomy of an asthma attack

When the respiratory system is working properly, the air we breathe passes in and out of the lungs through a network of airways. But for people with asthma, even a minor irritant will set off an immune response that can shut down the airways.

Asthmatic symptoms are usually quite variable, someone with asthma may go for periods of time without symptoms, and then suddenly have severe episodes for days at a time. The most common symptom is wheezing.

Routine treatment for asthma includes inhaled bronchodilators, injected epinephrine (adrenalin), or intravenous theophylline.

Bronchodilators are drugs which open up or dilate the constricted airways.

Taking anti-inflammatory drugs, aimed at reducing asthma is a relatively new approach to treating asthma. The idea behind it is that if the underlying inflammation of the airways is reduced, the bronchi may become less hyperactive, making future attacks less likely.

For asthma which is strongly triggered by allergies, allergen avoidance can often greatly reduce the amount of medication needed to control the asthma. Taking anti-allergic medications or taking shots for allergy desensitization are other alternatives.

Bronchitis

Bronchitis is an inflammation of the bronchi, the large airways inside the lungs. (Bronchiolitis is the inflammation of the bronchioles, the small airways.) The inflammation causes these passages, or bronchial tubes, to increase their production of mucus that is thick and yellow or grey in color, which is then coughed up. Bronchitis may be either acute or chronic.

Symptoms of acute bronchitis include fever, chest pain, and a cough that brings up mucus. Acute bronchitis can be caused by a respiratory infection, such as a cold. It also can result from breathing irritating fumes, such as those of tobacco smoke or polluted air.

Doctors consider the condition chronic if such coughing lasts for several months in each of two or more successive years. Chronic bronchitis may produce shortness of breath and, in severe cases, heart failure. The most common cause of chronic bronchitis is cigarette smoking. Either type of bronchitis may lead to asthma or pneumonia.

Bronchitis may be treated with drugs that expand the bronchial tubes, or with compounds that loosen mucus so it can be coughed up more easily. Moist air also helps loosen mucus. Antibiotics are prescribed if a bacterial infection is present. Most cases of acute bronchitis clear up within weeks. Chronic bronchitis cannot be cured.

The doctor may recommend cough medicines, antibiotics and plenty of bed rest. Chronic bronchitis usually persists for long periods of time and occurs most often in heavy smokers or as the result of recurring episodes of acute bronchitis. If you have bronchitis and smoke, you should stop. Smoking puts you at risk of emphysema, a life-threatening disease that deteriorates the lungs.

An antibiotic or inhaler is often prescribed. Cough medicines should not be used with chronic bronchitis because coughing is the only way the lungs can get rid of the mucus.

Influenza

Influenza, commonly called the flu, is an acute, contagious, respiratory tract infection, which is caused by one of the influenza viruses. The severity of influenza symptoms depends on the type of influenza virus, and the age and health of the patient. Influenza may produce no symptoms, mild-to severe symptoms, or fatal illness.
 

The common cold and influenza share many symptoms. However, colds are more likely to cause sneezing and a stuffy nose, while influenza is characterized by fever, coughs and muscle aches. Flu symptoms also develop rather suddenly, and are more severe. A person with influenza may experience chills, moderate to high fever (101o F to 103o) sore throat, runny nose, muscle and headaches, fatigue, cough, diarrhoea and dizziness.
 

The specific type of influenza is determined by the type of influenza virus (A, B, or C) that is causing the illness. Types A and B influenza viruses are responsible for epidemics that occur especially in winter.