Asthma-Free Naturally: Everything you need to know about taking control of your asthma. Patrick McKeown
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stress, and weather types such as fog and damp. In some instances an asthma attack may be triggered by a combination of catalysts. Anxiety can be caused by the variations on the asthma theme, particularly where a child is involved. Sometimes, there may be confusion between doctor and patient when a diagnosis is being made.
There is also a wide variety in the symptoms of asthma. The following is a list of those most commonly experienced by sufferers.
♦ Wheeze
This is a high pitched whistling sound produced when air is forced through narrowed airways. If you blow through a Biro pen when the ink refill is removed, the sound is similar.
♦ Breathlessness
This is the feeling of not being able to take in enough air. There is a need to breathe out while, at the same time, a compulsion to breathe in. If this symptom develops to an extreme level it can be frightening for the sufferer and very distressing for those close to him or her.
♦ Coughing
This may be either a repetitive dry cough or a cough with phlegm, often occurring during the night or early morning. Repetitive coughing can put a strain on the heart and drives sputum deeper into the lungs. Patients with this symptom may feel like they are on a conveyor belt: the more they cough, the more they feel the need to cough again.
♦ Chest tightness
Trapped air in the lungs generates a feeling that the chest is over inflated. This is often described as someone squeezing or sitting on one’s chest.
♦ Frequent yawning
When asthma symptoms are at their worst, sleep is interrupted by difficult periods of breathing which contributes to tiredness.
Non-asthmatics can, of course, observe these symptoms, but they will not appreciate the feelings of tension, panic, uncertainty and helplessness which accompany them, particularly when the asthmatic struggles to breathe. If you are not an asthmatic, imagine trying to breathe while a pillow is being pressed firmly over your face. That feeling you imagine is the feeling someone with asthma has during an attack. In your case, the imaginary pillow can be easily removed to allow you to breathe effortlessly; for an asthmatic, the remedy is not so simple.
Given the variety of symptoms and their severity, diagnosing a condition that has no commonly accepted definition is not an exact science. Many asthma symptoms are also the symptoms of other conditions, such as chronic bronchitis or bronchiectasis, for example. Diagnosis has to take into account the chronic nature of asthma and the constriction of the airways due to inflammation by various cells and chemicals. Generally, diagnosis of asthma is based on the following factors.
♦ History of the patient
This includes establishing if the patient has experienced asthma symptoms while at rest, during exercise or after exposure to a known trigger.
♦ Lung function tests
The peak flow meter measures the maximum speed at which the patient can exhale air in one second. A person with asthma usually produces a lower reading, and, generally speaking, a more inconsistent range of results than a person who doesn’t suffer from the condition. Spirometry measures both the speed and volume of air which is exhaled with each breath, thereby providing additional airway obstruction information.
♦ Effect of reliever or steroidal medication
In part, diagnosis of asthma is based on the effects of medication, and whether or not it leads to a temporary reversal of symptoms. Other conditions which demonstrate common asthma-type symptoms, such as emphysema, include irreversible airway obstruction.
♦ Provocation test
The patient inhales a broncho-constricting agent, such as histamine or methacholine. The airways of people with asthma are far more responsive to inhalation of these substances; agents like these will provoke more extensive narrowing of air passages in people with asthma.
♦ Skin tests to determine allergies
A number of common allergens are selected, such as dust mites, pollen or animal dander. One at a time, the allergens are placed on the forearm, and the skin is then gently pierced to allow the substances to penetrate. After fifteen minutes, the skin surrounding this spot may develop a small rash. While this test is not always conclusive, the presence of a rash and the size of the weal indicate an allergy to a specific substance.
♦ Chest x-ray
X-ray is used to rule out other respiratory diseases in a person who has the symptoms of severe chronic asthma. X-ray charts show irreversible damage to the airways, and this aids the diagnoses of other respiratory disorders.
Your respiratory system
Before you commence breathing retraining, it is important for you to have a basic understanding of the roles played by the respiratory system and carbon dioxide in your body. Your respiratory system consists of the parts of your body used for the delivery of oxygen from the atmosphere to your cells and tissues, and for transporting the carbon dioxide produced in your tissues back into the atmosphere. If cells and tissues are to function properly – if you are to live – your body needs the atmosphere’s oxygen. Your nose, mouth, pharynx, larynx, trachea, bronchi and lungs are all part of your respiratory system.
Part of your airways is your nose and mouth. Through them, air enters your body and flows down a flexible tube called the trachea. This tube eventually divides into two branches called bronchi: one branch enters the left lung and the other branch enters the right. Within your lungs, the bronchi further subdivide into an estimated twenty-five smaller branches called bronchioles. The bronchioles run into alveolar ducts and at the end are small air sacs called alveoli.
Look at it another way. Imagine an upside-down tree. The trachea is the trunk; at the top of the trunk are the two large branches of the bronchi. From each of these large branches grow the smaller branches of the bronchioles. At the end of each smaller branch are the ‘leaves’, the round balloon-shaped sacs called alveoli.
When you breathe in, air enters through your nose or mouth and flows into the trachea, the bronchi, bronchioles and eventually alveoli. The grape-like alveoli – after which they are named – are surrounded by tiny blood channels called capillaries. Oxygen enters the blood by passing through a very thin barrier between the capillaries and air sacs. It is then carried by what is called haemoglobin within
Our lungs
A close-up of Alveoli (air sacs)
the blood to tissues and cells. There are approximately three hundred million alveoli in the lungs, each of which is surrounded by tiny blood vessels.
To put this huge number in context, think of Wimbledon and imagine a tennis court. The area of contact between your alveoli and blood capillaries is equivalent to the size of a tennis court; as you can imagine, this massive area provides scope for an efficient transfer of oxygen from the air to your blood. Carbon dioxide is produced as an end product of the process of breaking down the fats and carbohydrates that you eat, and this gas is brought by your venous blood vessels to your lungs where the excess is exhaled. Crucially, part of your body’s quotient of carbon dioxide is retained when you exhale, and correct breathing results in the required amount of carbon dioxide being retained in your lungs.
There are two main aspects to the way you breathe. Your rate is the number of breaths you take in one minute and your volume is the amount of air drawn into your lungs.