Asthma (Children)

Respiratory system

Asthma is a common condition that affects the small airways or tubes in the lungs called bronchioles, making it difficult to breathe.

Asthma is a very common condition, estimated to affect one person out of every 5 households in the UK. Currently, there are over 5.4 million people receiving treatment for asthma in the UK, of which over 1.1 million are children. Worryingly, the number of children affected by asthma is on the increase. There are over 1200 deaths per year in the UK caused by asthma.

No one knows exactly why some people develop asthma and others do not. It is probably a combination of genetic and environmental factors. Children are more likely to develop asthma if there is a history of asthma, allergy or eczema in the family. Environmental factors such as house dust mite, pollution, passive smoking, or a viral infection probably combine with genetic factors to increase the chances of getting asthma.

When a child develops asthma, the cells in the airways become overly sensitive and are easily irritated. When this happens, it becomes difficult for the child to breathe and the child is said to be suffering from an asthma attack

To understand what is happening during an asthma attack, it is important to know something about the structure of the airways.

The small airways in the lungs, called the bronchioles, have an outer muscular wall and a soft inner lining. The outer muscular wall controls the size of the opening of the airway. When the muscles relax the opening of the airways gets bigger, making it easier to breathe and allowing more air into the lungs. This process is referred to as bronchodilatation. When the muscles contract the opening of the airways gets smaller, making it harder to breathe and allowing less air into the lungs. This process is referred to as bronchoconstriction or bronchospasm. The cells of the soft inner lining of the bronchioles produce mucus that traps dust and other small particles in the air that is breathed, helping to clear these unwanted substances from the lungs.

During an asthma attack, the muscles in the walls of the airway contract (bronchospasm) making it difficult to breathe. At the same time, the inner lining of the airway becomes swollen or inflamed and produces lots of mucus. The swelling of the lining and the increased amount of mucus make the narrowed airway even narrower and breathing even more difficult.

Many things may trigger an asthma attack. These include things that are breathed into the lungs, such as dust, pollen, cigarette smoke and animal fur. Cold air or exercise may trigger an attack, as can stress or a chest infection. Some medicines are also capable of triggering an asthma attack if the person is sensitive to them. Everybody is different, not everyone will respond to the same triggers and some children may have several triggers.

Symptoms of asthma may vary from the very mild to the life threatening. In their mildest form, the child may have a slight cough or a wheeze. More severe symptoms include tightness in the chest and shortness of breath. Symptoms vary from day to day and are often worse during the night or during exercise. In its severest form, an asthma attack may come on very suddenly and the child will not be able to breathe.

The treatment of asthma falls into two main categories - relievers and preventers. Relievers work quickly to ease the symptoms of an asthma attack. They should be used at the first signs of an asthma attack beginning. Preventers help reduce the number of asthma attacks by reducing the sensitivity of the airways to triggers. Preventers need to be taken all of the time, even when the child is breathing normally. Most relievers and preventers are available as inhaler devices that deliver the active medicine directly into the lungs. Some are also available in liquid or tablet form to be taken by swallowing.

Relievers
Relievers include drugs known as short-acting beta2 agonists, for example salbutamol and terbutaline. These drugs act on the muscles in the airways making them relax, producing bronchodilatation and so making breathing easier. For this reason, these drugs are also called bronchodilators. Both salbutamol and terbutaline act quickly, so when taken at the first sign of an asthma attack can help relieve symptoms. The actions of both drugs may only last for a few hours which means that doses may need to be repeated to control the asthma attack.

Other relievers include drugs known as anticholinergics, for example ipratropium bromide. This drug also causes bronchodilatation but it is not as fast acting as salbutamol and is not used for the relief of asthma attacks. Instead, it is usually used with other treatments when asthma symptoms fail to improve.

Preventers
Preventers include drugs known as inhaled steroids, for example beclometasone, budesonide, ciclesonide, fluticasone and mometasone. These drugs act to reduce the sensitivity of the airways to triggers. When taken regularly they reduce inflammation of the airways and reduce mucus secretion. They need to be taken regularly to be effective.

Long-acting beta2 agonists, for example formoterol and salmeterol also cause bronchodilatation but because they act slowly they are not suitable to relieve acute asthma attacks. They are normally used with inhaled steroids to help the long term control of asthma symptoms. They should not be used to replace steroids as this may cause life threatening asthma attacks. The long-acting beta2 agonists may also be useful in controlling asthma attacks that occur during the night.

Montelukast and zafirlukast, drugs known as leukotriene antagonists, may also be added to standard bronchodilator and steroid therapy to control asthma. These drugs come in tablet from rather than as inhalers, and inhibit the action of a chemical called leukotriene that is released in the lungs during an asthma attack and which is responsible for causing inflammation.

As the various asthma treatments have different actions or are used for different purposes, several products are often used together to help control asthma. Most children with asthma will require regular treatment everyday to reduce their symptoms, and also treatment for relief if an asthma attack suddenly occurs. Treatment will depend on the severity of the asthma, and it may change from time to time as symptoms ease or get worse.

Asthma is a long term condition that may require treatment for years. In such circumstances it is worth registering with your pharmacist for the repeat dispensing of your child's prescriptions. By doing so, your pharmacist will get to know the medicines your child is taking and is always available to offer advice. At regular intervals, your pharmacist may suggest that he or she reviews the medicines being taken to ensure that they are being used properly. It also provides an opportunity for you to discuss any questions about your child's medicine and how it should be used. If your pharmacist considers that your child's asthma is not being controlled, you will be advised to visit your doctor or asthma specialist nurse.

With good advice and modern medicines, it is possible for most children to control their condition and lead a life unrestricted by their asthma. Most of the treatments available now are easy to take and, in the recommended doses, are effective and carry little risk of causing any side effects.

Asthma can not be cured, but with the avoidance of triggers, proper monitoring and the correct treatment it can be controlled, allowing a child to live a full and normal life and to do the things all children do.

Try not to be over-protective, asthma should not be used as an excuse to prevent your child playing with friends or taking part in activities. These are an important part of any child's development.

Teaching your child as soon as possible to recognise the symptoms and causes of asthma and to understand the importance of using treatments as the doctor or nurse has advised is the best way of controlling asthma and allowing your child eventually to lead an independent life.

Develop a Personal Asthma Action Plan. It will help your child understand the medicines and what to do if symptoms get worse and it will give you peace of mind.

Help your child to identify the things that trigger an asthma attack. You cannot be with your child every minute of every day and so it is important that your child knows what to avoid.

Encourage your child to eat a healthy, balanced diet rich in fresh fruit and vegetables, and to keep weight under control. Unless specific foods are known to make your child's asthma symptoms worse, there is no need to have a special diet.

Inform the school that your child has asthma and provide written instructions on any medicines that need to be taken during the school day. Make sure that the school has adequate supplies of all medicines, including a spare reliever, clearly marked with your child's name. Also provide written instructions of what to do in the event of your child having an asthma attack, and tell the school if there has been any change in your child's asthma.

Get to know your child's symptoms. It will help you recognise how well asthma is being controlled. If your child is using a reliever inhaler more than once a day, if coughing or wheezing regularly, waking up at night or just not able to do things that other children can do without getting out of breath, then it may mean that your child's asthma is not as well controlled as it might be. Make another visit to your doctor as a change in your child's treatment may be necessary.

Ask yourself if you child is achieving the following goals, if not see your doctor or asthma specialist nurse:

• Free from symptoms day and night
• Has normal or best possible lung function, and maintains it
• Has reduced the risk of severe attacks
• Has minimised absence from school

Asthma UK is the charity dedicated to improving the health and well-being of people in the UK whose lives are affected by asthma. Asthma UK runs an advice line operated by asthma specialist nurses. Its website provides comprehensive information about asthma and gives practical advice for parents.
Asthma UK Adviceline
Asthma UK
Summit House
70 Wilson Street
London
EC2A 2DB
Helpline: 0800 121 62 44
www.asthma.org.uk

Reviewed on 6 December 2010