History and Diagnosis of Asthma
Today there is no universal definition of asthma. In any good medical book, it describe more technically whereby any sufferer will not understand the technical terms. Whereas in a dictionary, it describes as ‘a disese of respiration related to difficult breathing, cough and etc which any asthma sufferer is familiar even if it varies from uncomfortable condition to life threatening.
Today asthma is a wide spread news. In the late twentieth century the condition of asthma increased to the extent that an estimated 100 to 150 million people in the world are affected.
The term “asthma” is a Greek translation of gasping or panting and the problem was treated as far back as 2000 BC by Chinese doctors with the herb Ma Huang. The first known recording of the symptoms was about 3,500 years ago in an ancient Egyptian manuscript called Ebers Papyrus. Throughout the ages, asthma has received varying degrees of attention, the symptoms and their accompanying anxiety have been described by many prominent historical figures, one to mention is the famous Greek physician, Hippocrates.
Over the centuries, there has been variety of different theories about the causes of asthma. An vast range of remedies has been advised such as horse riding, strong coffee, tobacco, faith healing, chloroform and even drinking the blood of owls in wine as practiced by the ancient Romans. Van Helmont who lived in the early part of the seventeenth century claimed that asthma was epilepsy of the lungs due to the sudden and unpredictable nature of an attack. An English physician Thomas Willis basing on his own experience of asthma said that “the blood boils” and that “there is scarce anything more sharp or terrible than the fits thereof”.
However in the eighteenth century Lavoisier provided the first real account of the functioning of the lungs, the basis of modern-day understanding of the respiratory system. It was commonly believed that air was drawn into the lungs to cool the body. Lavoisier’s contribution was that air is drawn in to be converted to energy by the metabolism and that carbon dioxide and heat are produced as end products of the process. Lavoisier’s work recognized that oxygen is essential to sustaining life.
Asthma now affects more people throughout the world, particularly in more developed countries, than at any other time in evolution. According to the World Health Organisation’s (WHO) April 2002 report on the links between ill health in children and the deteriorating environment, asthma inflicts greater economic and social damage than TB or HIV in Western Europe.
According to the 1998 International Study of Asthma and Allergies in Childhood (ISAAC), the countries with the highest twelve-month incidence of asthma were the UK, Australia, New Zealand and the Republic of Ireland followed by North, Central and South America. The same report found that the lowest rates were in centres in several Eastern European countries, followed by Indonesia, Greece, China, Taiwan, Uzbekistan, India and Ethiopia. Other studies show that the rate of asthma among rural Africans who migrate to cities and adopt a more ‘western’ urbanised lifestyle increases dramatically. According to the UCB Institute of Allergy in Belgium, the incidence of asthma in Western Europe has doubled in the last ten years.
In the Western world, asthma crosses all class, race, geography and gender boundaries. Although it causes persistent symptoms among seventy per cent of all people diagnosed with it, asthma causes only minor discomfort to the majority. In fact, some of the most influential people of our time were asthmatic, including Russian Tzar Peter the Great, actors Liza Minnelli, Jason Alexander and Elizabeth Taylor, revolutionary Che Guevara, and former US presidents John F Kennedy, Calvin Coolidge and Theodore Roosevelt. All these people have lived long or are still living.
What are the symptoms?
The condition consists of inflammation, tightening and swelling of the airways in the respiratory system, resulting in obstruction of the flow of air to and from the lungs. The symptoms of asthma also include breathlessness, wheezing, coughing and chest tightness. Sufferers may also have a blocked nose and hay fever, or rhinitis. The symptoms and their severity are peculiar to the individual, and they vary from season to season and according to the individual’s susceptibility to a wide range of triggers.
An ‘asthma attack’ is characterised as an episode of breathing difficulty. In some cases, this may be an exposure to a specific trigger such as dust, pollen or certain foods, however in certain cases there appears to be no particular trigger. Some people may experience wheezing and a very little cough while other may have cough but no wheezing, however each case is accompanied by some level of breathing difficulty. Symptoms may occur periodically, daily or seasonal basis, otherwise more or less continuous.
A ‘trigger’ is something that makes asthma worse. The most common triggers include (in alphabetical order): allergies; cigarette smoking (and cigarette smoke for non-smokers); colds and ‘flu; cold air; dust mites; exercise under certain circumstances; moulds; noxious fumes; pollens; stress, and bad weather such as fog and damp. In some instances an asthma attack may be triggered by a combination of catalysts. Anxiety, particularly in children can be caused by the variations on the asthma theme. Sometimes even confusion arises between the doctor and the patient when a diagnosis is being made.
There is also a wide variety in the symptoms of asthma. The following is the most commonly experienced by sufferers.
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.
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 threatening for the sufferer and very distressing for those close to him or her.
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 critical stage, sleep is interrupted by difficult periods of breathing which contributes to tiredness.
Non-asthmatics can observe these symptoms, but they will no longer tolerate the feelings of tension, panic, uncertainty and helplessness which accompany them, particularly when the asthmatic patient is breathless. If you want to experience the feelings of someone with asthma attack, imagine trying to breathe while a pillow is being pressed firmly over your face. In your case, the imaginary pillow can be easily removed to allow you to breathe effortlessly but for an asthmatic, the remedy is not so simple.
Inspite of 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 for example chronic bronchitis or bronchiectasis. 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
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 to provide additional airway obstruction information.
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 symptoms of asthma is emphysema that relates to 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 also aids the diagnoses of other respiratory disorders.