What is Asthma?
Asthma is a clinical syndrome which can manifest as shortness of breath, coughing, wheezing and chest tightness. When all of these symptoms occur together, asthma is more likely. However, patients can have only one or two of these symptoms, and still have asthma. The symptoms of asthma arise from constriction and swelling of the airways, which tends to occur intermittently for most people. As a result, most people with asthma have intermittent symptoms.
What causes asthma?
Asthma can be allergic or non-allergic in nature. In allergic asthma, patients usually have features of other allergic diseases also, such as seasonal hay fever, or eczema, or a past history of such diseases. This is not universally true though, and some people can just have allergic asthma. The allergies of significance vary for different people, but house dust mites would be the most common allergen of interest. Others can include pollens, grasses, pet dander (cats especially) or domestic molds. A family history is also common, as asthma often runs in families. Non-allergic asthma may occur as a result of exposure to certain pollutants, cigarette smoking or frequent chest infections. Some people are also sensitive to certain medications, such as anti-inflammatory medications.
What to do in case of Asthma Emergency (Adult and Children)?
Asthma attacks, otherwise known as exacerbations, or “flare-ups” can be a medical emergency. This can occur in the context of infections, usually viral in nature, or from high level allergen exposure, as we saw with the thunderstorm asthma events of last year in Melbourne. It is important for a patient to recognise when their asthma symptoms are becoming uncontrolled, and to implement their GP derived asthma action plan. Having an asthma action plan has been shown to reduce the likelihood of a patient ending up in the hospital with their asthma. If the instructions on the asthma action plan are not effective, then the patient should visit their GP or, if they are struggling with their breathing, call an ambulance.
How is Asthma managed?
It is very important that a patient regularly uses their asthma preventer inhaler, as prescribed, and not just when they are starting to feel unwell, as often, it will not work effectively if the asthma attack has already occurred. These medications are referred to as “preventers” as we want the patient to use them when they are well, to “prevent” the patient from becoming unwell.
In addition to using inhaled medications as prescribed, patients should avoid cigarette smoking and avoid allergen triggers which are known to affect them, such as cat dander or excessive dust.
Patients with asthma should remain up to date on their vaccinations and have an asthma action plan, which has been personalised for them, with their GP.
When asthma symptoms are still an issue or exacerbations remain frequent, we have additional management strategies for asthma patients available now. An example is Bronchial Thermoplasty (BT), which is a day procedure, which reduces the smooth muscle in a patient’s airway. This can significantly improve asthma symptoms and exacerbation frequency in appropriately selected patients.
What is bronchial thermoplasty (BT)?
As mentioned, asthma is a disease of the airways, whereby the smooth muscle within the patients air tubes becomes swollen, and constricts the airways. This results in difficulty breathing, as the lumen of the air tube is now smaller than it should be. To date, we have relied on medications to treat this, by reducing the inflammation within the airway, and by relaxing the smooth muscle.
Bronchial Thermoplasty (BT) is a novel procedure that involves inserting a camera (bronchoscope) into the patient’s airway, under light sedation. A special catheter is then deployed, which emits low level radiofrequency energy into the smooth muscle of the airway, leading to shrinkage of the muscle. Over time, there will be much less smooth muscle within the airway, and therefore, much less airway narrowing or constriction. This has been shown to significantly reduce the burden of asthma symptoms and medication usage, in appropriately selected patients.