lunes, 7 de abril de 2014

COPD (Chronic Obstructive Pulmonary Disease)

COPD is a disabling condition affecting the lungs and involving irreversible lung damage, so that the lungs can no longer function at full capacity.
COPD comprises two related lung diseases:
-Chronic bronchitis: results from inflammation and irritation of the airways in the lung. This causes airway narrowing, which can cause shortness of breath or wheezing. It is characterised by the presence of cough and phlegm production for more than three months in two consecutive years.

-Emphysema; air sacs deep within the lungs, where oxygen is absorbed into the bloodstream, are prone to damage from toxins such as tobacco smoke. Emphysema develops when the air sacs enlarge and are no longer able to function properly. This results in poor oxygen delivery to the blood circulation.
The chest muscles that are involved in breathing in people with emphysema have to work harder in order to sustain an adequate oxygen level in the blood. This contributes to breathlessness, which is made worse by the associated collapse in the surrounding airways caused by the loss of the lungs natural elasticity as a consequence of lung tissue destruction. Air gets trapped in the lungs when the airways collapse during exhalation and this leads to hyperinflation of the lungs where the volume of the lungs becomes larger than normal.

There is ongoing inflammation in the airways in COPD. The onset of breathlessness is gradual over time.

Symptoms of COPD
-Many people get used to their COPD without realising it, especially in the early stages of the condition.
-You may find that you become tired easily when gardening or get out of breath when walking on an incline.
-People with COPD also tend to produce phlegm, particularly in the mornings.
-You may find that you always need to bring up phlegm by constantly coughing.
-You may also find it hard sometimes to shift phlegm from your lungs.
-The phlegm is usually clear in colour. Green or brown discoloration of thickened phlegm usually indicates an infection. Chest infection is common in people with COPD, especially during winter months. It is important to recognise infection early and to seek medical treatment.

Causes of COPD
-Smoking is the main cause of COPD.
-Other causes of COPD: alpha-1-antitrypsin deficiency, chest infections, bronchiectasis, chronic asthma and occupational exposures.

Other complications from COPD
-Breathlessness, is a frequently occuring symptom of heart failure.
-Swollen ankles, can be also a symptom of heart failure.
COPD can be very disabling; there is currently no known cure but appropriate treatment and support will help.

Treatment
The main aim of treatment is to relieve breathlessness. It does not reverse or cure the underlying condition but may improve symptoms and reduce flare-ups.
There are several forms of treatment available divided into two categories:
  • Inhaled therapy: reliever (when the need arises) and preventer (they need to be taken regularly) medication.
Class of medication:
-Corticosteroids (preventer, usually twice daily): beclometasone (AeroBec), budesonide (Pulmicort) and fluticasone (Flixotide).
-Beta-2 agonists short acting like salbutamol (Ventolin) and terbutaline (Bricanyl), they are taken when the need arises and their effects last for around 2 hours.
-Beta-2 agonists long acting like formoterol (Oxis) and salmeterol (Serevent), they keep the airways opened for up to 12 hours, used as a preventer medication usually twice a day.
-Anticholinergics short acting; can relieve breathlessness for up to 6 hours, usually used four times daily like ipratropium (Atrovent).
-Anticholinergics long acting: can keep the airway open for up to 24 hours, used once daily like tiotropium (Spiriva).

Examples of combination inhalers are:
-Combivent (ipratropium plus salbutamol).
-Seretide (fluticasone plus salmeterol).
-Symbicort (budesonide plus formoterol).

Types of inhaler devices:
-Pressurised metered-dose inhalers.

-Dry powder inhalers.

-Nebulisers.

-Using a spacer.

  • Oral therapy:
-Corticosteroids: are used mainly during a flare-up. They control inflammation of the lungs and may help in hastening recovery.

-Methylxanthines: may be used in addition to inhaler medication. They inhibit enzymes (phosphodiesterases) involved in the inflammatory process in the body and by doing so help reduce inflammation in the airways. They need to be taken daily and regular blood tests will be required. An example is theophylline (Phyllocontin).
-Mucolytics: they loosen the phlegm in the lungs making it easier to cough up. Carbocisteine (Mucodyne) and mecysteine (Visclair) are mucolytics.
-Antibiotics: may be used during a flare-up because they kill bacteria and prevent it from multiplying. They should not be used routinely to prevent infections as this may cause antibiotic resistance. Some antibiotics used are amoxicillin and clarithromycin.
-Antidepressants: may be prescribed to help with anxiety and depression related to COPD. Usually taken once daily like citalopram and paroxetine.
-Anti-phosphodiesterases: they reduce inflammation in the airways and may help with breathlessness, roflumilast and cilomilast are some examples.

  • Oxygen therapy: can be used either continuously or qhen the need arises but it may not be suitable for everyone with COPD.

Source: COPD Chronic Obstructive Pulmonary Disease, Dr Daniel Lee, Family Doctor Publications 2008.

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