Asthma or Bronchial Asthma is a common disease. About 75 % cases start in childhood before 10 years of age. A large no of patients stop having symptoms at the time of puberty and some may again have the disease in the later years. It is uncommon after 50 years of age. It can be troublesome, disabling and if not treated properly may be dangerous.
The disease results from heightened reactivity of the airways in response to irritants, allergens, fumes and at times exercise. It is typically intermittent and a person feels well when there is no ongoing attack of asthma.
Symptoms of asthma are shortness of breath, difficulty in breathing, cough and whistling sounds during breathing. These symptoms may also be seen in a no of heart, lung or infective conditions. Hence the diagnosis is usually made by experienced doctors after a few episodes have occurred!
The important markers of the disease are rapid reversibility of the signs and symptoms with appropriate treatment or spontaneously. Patients or their relatives often give a history of allergy.
The allergy may be due to seasonal pollens, pets in the house, dust from the carpets, molds, mites and many other substances. A person may be allergic to medicines. Aspirin can sometimes precipitate asthmatic attacks.
Attacks may come after short bursts of physical activity or after sustained effort. It can come after a few minutes of exercise and lasts for ½ to 1 hour. Since heart conditions (valvular and ischemic) may also cause shortness of breath or difficulty in breathing, the distinction between these conditions is necessary. The time profile here may provide a clue to the doctor. If examined during an attack of asthma, physicians or nurses hear musical sounds (called rhonchi ) during exhalation. These occur at varying frequency and loudness in different parts of the chest. These are absent in between attacks. These may be absent during very severe attacks.
Blood tests are of little value in diagnosis. Eosinophils are often increased in the blood. In severe cases, level of oxygen and carbon dioxide in the blood is required.
Spirometry is carried out by the patient inhaling maximally and breathing out as fast as possible. The amount of air expelled in the 1st second as a percentage of the total inhaled volume is low. The importance of diagnosis is mainly in demonstrating the reversibility rapidly after drugs used to widen the bronchial airways. The drugs used are albuterol, salbutamol or terbutaline. This demonstration is sometimes required in cases where the diagnosis is not clear.
Chest X Rays are usually normal.
This consists of drugs used to widen airways and prevention of allergens and precipitating agents. These are beta agonists or anticholinergics. In severe cases, steroids and anti-inflammatory and immunosuppressing drugs are required for short periods. The drugs are preferably administered by inhalation after atomization through various devices. This reduces the amount of medicines as these go directly to the area of the disease. This curtails the bronchitis side effects of the medicines. Nebulisation is used for sustained delivery of drugs. In severe cases even mechanical ventilation is required during acute stages. Early treatment of episodes of asthma may ward off complications and hospitalizations.