Chronic obstructive pulmonary disease (COPD)

The purpose of this website is to provide general information on COPD to patients and their carers, although healthcare workers - such as nurses, physiotherapists and pharmacists involved in the care of patients with COPD - may find the sections on inhaler technique useful. Management of this group of patients is based on the recommendations of the NICE guidelines on COPD published in June 2010. Please note that patients may experience some of these symptoms at times of exacerbations, but not everything you read here will be applicable to each individual patient. A summary of the NICE guidelines is available from: www.nice.org.uk/nicemedia/live/13029/49399/49399.pdf

What is COPD?

Why is COPD important?

What is the size of the problem?

Who develops COPD?

How is COPD diagnosed?

How is the severity of COPD assessed?

What other tests will I need?

What is the management of COPD?

What treatments are available for COPD?

How do I take my inhalers?

Oxygen therapy

Acute exacerbation of COPD

Follow up after a hospital admission

Other considerations

COPD self management plan

Surgery

COPD services at West Middlesex hospital

We are continually looking to improve the information we give to patients. If you have any comments or feedback on this section, please email them to communications@wmuh.nhs.uk  

What is COPD?

COPD is a condition characterised by narrowing of the airways in the lung (airflow obstruction) and lung tissue damage, which is usually progressive, not fully reversible, and does not change markedly over several months. The disease is predominantly caused by smoking in 90% of cases. It can result in symptoms of shortness of breath, chronic cough and wheeze. Approximately 15-20% of all smokers will develop this condition.

Worsening of COPD symptoms (known as exacerbations) can occur, and are characterised by sometimes rapid and sustained worsening of symptoms. Patients may need to see their GP, or else go to hospital if their usual inhalers and treatments are not helping. They may need treatment with steroid tablets (prednisolone), antibiotics, nebulisers and oxygen.

COPD is a general term which includes conditions such as chronic bronchitis, emphysema, and some cases of chronic asthma. It excludes certain conditions in which there may also be airflow obstruction such as Cystic fibrosis (usually presents in childhood) and bronchiectasis (thickening and dilation of the airways usually following chest infections).

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Why is COPD important?

COPD is a big problem, not just in this country, but around the world. It accounts for approximately 30,000 deaths per year in UK and is the 4th main cause of death worldwide.  It accounts for 1 in 8 of all hospital admissions and £1,500 million per year in lost productivity through sickness and time off work. The 2008 Royal College of Physicians/ British Thoracic Society audit of COPD exacerbations has revealed significant variations in outcomes between different hospitals in England and Wales implying that there is scope to improve outcomes by standardising care. In this audit, the usual average length of stay in hospital was 5 days. The audit also showed that at 3 months follow up after an admission, 14% of patients had died and 33% had been readmitted to hospital.

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What is the size of the problem?

COPD is significantly under diagnosed worldwide. In England and Wales, it is estimated that there are 3 million people with suspected COPD, but it is thought that only 900,000 have been diagnosed. National data suggests that 10% of adults over 45 years will have COPD, and this approximates to 8,200 potential cases of COPD in Hounslow. Hounslow PCT data however, shows that there are only 1,798 patients on COPD registers in 2008-9, so there are many patients who smoke in whom COPD has not been diagnosed.

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Who develops COPD?

The NICE guidelines for COPD published in 2010 recommends that COPD should be considered in any one aged 35years or over who is a smoker or has smoked in the past, and who has symptoms of chronic cough, regular sputum production, shortness of breath (dyspnoea) on walking, or frequent episodes of winter ‘bronchitis’ (cough and sputum) and wheeze. These symptoms are usually present on a daily basis and can become worse if the patient has a bacterial or viral infection, or inhales fumes or dust (for example, pollution) which can make their symptoms worse. There should be no features of asthma, which include variable symptoms of cough, shortness of breath and wheeze which can be triggered by certain allergens such as exposure to animals, strong smells such as perfumes, pollen, cold weather or exertion. Asthmatics usually feel unwell at times of exacerbations but symptoms usually improve either by themselves or with treatment and they are well in between attacks. They may wake up night due to breathlessness or cough and need to use their inhalers, but generally do not produce sputum. Some asthmatics may smoke, and this can make the diagnosis of asthma or COPD difficult at times, and some patients may have both asthma and COPD.

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How is COPD diagnosed?

The airflow obstruction in COPD is detected by asking the subject to blow into a machine called a spirometer which measures how narrow the airways are. After taking a deep breath in, the subject breaths out (exhales) into a mouth piece connected to the spirometer and breaths out as hard and for as long as they can (ideally for 6 seconds). This is carried out 3 times and the best attempt recorded. The important reading is the forced expiratory volume in 1 second (FEV1), and this measures the amount of air that can be expelled from the lungs in the first second of exhalation. The total volume of air that can be exhaled in 6 seconds is known as the forced vital capacity (FVC). The ratio between these readings, FEV1 divided by the FVC (FEV1/FVC) is usually less than 70% in patient who have COPD. If it is more than 70%, then the patient may not have COPD and another condition may be present. The following diagram shows the typical results from a spirometer displayed in a graph called a spirogram.  

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How is the severity of COPD assessed? 

The severity of the airflow obstruction can be assessed is by looking at the level of the FEV1. Before spirometry, patients are given a salbutamol (ventolin) inhaler in to open their  airways, and then the best FEV1 from 3 attempts will be recorded. The amount of airway narrowing can be classified as follows: 

Post ventolin                           FEV1 %                      Severity

FEV/FVC ratio                        predicted

<70%                                       ≥ 80%                          stage 1-mild (if symptoms)

<70%                                       50-79                           stage 2 –moderate

<70%                                       30-49                           stage 3-severe

<70%                                       <30%                           stage 4-very severe

(or FEV1<50%, with respiratory failure)                                                                                              

It is now known that COPD does not just affect your lungs but can affect you in other ways. For example, patients with more severe disease can lose muscle mass and lose weight, and may also develop anxiety or depression. A number of factors determine how severe your COPD is, and not just the level of airflow obstruction (FEV1). Other important factors to consider include the number of exacerbations (flare ups) and the level of breathlessness. This can usually be graded using the MRC (medical research council dyspnoea (breathless) scale which is recommended for the assessment of disability of COPD depending on the amount of exertion that it takes to make you breathless:

MRC score 1-short of breath on strenuous exertion

MRC Score 2-short of breath on hurrying on a level surface or walking up a slight hill

MRC Score 3-walking slower than people of the same age on the level, or stops for breath while walking at own pace on the level 

MRC Score 4- stops for breath after walking about 100 yards

MRC Score 5- too short of breath to leave the house or short of breath when dressing

Other factors that are important to consider when assessing severity of COPD include exercise capacity, body mass index (BMI- weight in kilograms divided by height in meters squared: kg/m2), gas transfer level as measured by full lung function tests (gives a measure of how good your lungs are at getting oxygen from the air into your blood stream); the amount of oxygen in your blood stream as measured by a pulse oximeter or an arterial blood gas sample; the presence of right heart failure, which usually is a sign of more advanced disease and indicated strain on the heart.

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What is the management of COPD?

Stopping smoking is the most important first step in treating this condition. By giving up smoking, the rate which your lung function declines is reduced and this helps to prevent any further deterioration in lung function. You may be prescribed nicotine replacement products such as patches, gum or lozenges, or else, your GP may prescribe other products such as Bupropion (Zyban) or Varenicline (Champix). The choice of treatment will depend on what you have tried before, and the side effect profile of the drug.

This graph above shows the natural decline in lung function as subjects get older. Approximately 15% of smokers will develop COPD and show a greater decline in lung function (bottom line, as measured by FEV1 using spirometry). The dotted lines show that by stopping smoking, the rate of decline of the FEV1 can be slowed and this effect is seen at any age.

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What treatments are available for COPD?

The main form of treatment are inhalers called bronchodilators. These help to open up the airways and make it easier to breathe. The short acting bronchodilators (last 4-6 hours) include salbutamol (ventolin) and Ipratropium bromide (atrovent). Long acting bronchodilators (last 12 hours) include salmeterol (servent), and formoterol (oxis), while tiotropium (spiriva) is taken once a day and lasts for 24 hours. If symptoms are mild, then the short acting bronchodilators are used in the first instance, but if symptoms persist, the long acting inhalers are added. In some instances, combination inhalers such as seretide or symbicort are used. These inhalers contain a long acting bronchodilator and an inhaled corticosteroid, which are better than a long acting bronchodilator used alone.

Inhalers come in different devices and it is important that patients are confident in using their inhalers correctly. 

The algorithm below summaries the use of these inhalers in the treatment of COPD. 

KEY:

LABA-long acting bronchodilator (e.g. Salmeterol, formoterol)

LAMA- long acting muscurinic agent (e.g. Tiotropium)

ICS- inhaled corticosteroid (e.g. beclometasone, budesonide, fluticasone)

≥ - greater than or equal to

< - less than

LABA+ICS - usually given as a combination inhaler containing the two drugs e.g. symbicort or seretide.

If symptoms are not relieved with inhalers, then a tablet called aminophylline (theophylline) may be tried. This helps to open up the airways in a different way than inhalers. The drug has some side effects if the dose is too high, and thus a blood test is necessary after a few days to make sure that the level of drug is correct. Common side effects include nausea, vomiting, tremor and palpitations. The drug can also interact with other drugs such as antibiotics.

Mucolytics (for example, carbocysteine) are tablets that are sometimes used in patients who have a chronic cough productive of sputum. They can help to loosen up sputum and make it easier to cough up sticky sputum and have been shown to reduce infections.

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How do I take my inhalers?

Click here for inhaler techniques

Meter dose inhalers are best used with inhalers (aerochamber) to increase the amount of drug delivered to the lung. Many patients are unable to use a meter dose inhaler device.

If patients remain very short of breath despite using their inhalers and other treatments, then a trial of nebulised treatment may be tried. A nebuliser creates an aerosol of drug which is inhaled and may provide additional relief of breathlessness.  A trial of nebulisers is usually given in the hospital clinic, and if there is evidence of  improvement in symptoms and exercise capacity, then the patient will benefit from long term regular nebulisers. Not all patients find nebulisers beneficial, and some patients may find that they are more short of breath, or that it makes them cough more. Nebulisers may be given through a facemask or mouth piece. In general, nebulisers should be continued only if there is improvement in symptoms, exercise capacity, and lung function.

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Oxygen therapy

There are three types of oxygen supplies available.

Short burst oxygen   is given through cylinders in the patient’s home, and is usually prescribed if patients remain severely short of breath after minimal exertion despite other treatments, and should be continued only if breathlessness improves. This form of oxygen is usually used for 15-20 minutes after exertion if needed.

Long term oxygen therapy (LTOT) is usually prescribed in patients who have more severe disease (for example, FEV less than 30%, or those who have evidence of right heart failure or significant shortage of oxygen in their blood). Patients will usually have significant reduction in their exercise capacity. LTOT has been shown to improve survival in these more severe patients if used for more than 15 hours per day, using special tubing that is inserted into the nostrils. The aim is not to make the patient feel symptomatically better, but to keep the level of oxygen above a certain level (Pa02 above 8.0kPa) to prevent any an increase in pressure within the blood vessels in the lungs (pulmonary hypertension), which in turn puts the right side of the heart under strain.

Patients are assessed for LTOT if their resting oxygen saturations are below 92% when breathing room as measured with a pulse oximeter. This is carried out by taking an arterial blood gas analysis from an artery in the wrist, twice, 3 weeks apart. If the oxygen level is below a certain level (less than 7.3 kPa), then the patient is eligible for LTOT.

The UK MRC trial showed that using LTOT for 15 hours or more per day if there is  persistent Pa02 <7.3kPa on air improves survival compared to patients who do not use LTOT.

It is important that patients are warned not to smoke when they use oxygen, as there is a risk of facial burns, and fire or explosion. In a small proportion of patients, oxygen therapy cannot be given without causing an increase in carbon dioxide level (a waste product gas), and these patients need to use a non invasive ventilation machine with their oxygen.

Ambulatory 02

Ambulatory oxygen is the provision of portable oxygen cylinder for use outside the home. This can be prescribed for patients who are using LTOT but wish to go out of the house. Ambulatory oxygen can also be prescribed for patients who do not qualify for LTOT, but show a reduction in oxygen levels when they walk (drop in oxygen saturation level by 4% to a level below 90%). This should be prescribed only if there is evidence of improvement in exercise capacity and breathlessness. The aim is to keep the oxygen saturation level above 90%.

Click here to see images of oxygen cylinders/concentrator

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Acute exacerbation of COPD

An exacerbation (or flare up) of COPD is characterised by an increase in breathlessness, wheeze, and cough, with an increase in sputum volume or purulence (green/yellow coloured sputum), chest tightness, fluid retention (swelling of the legs). This may be treated either by the GP or in hospital. An exacerbation is usually treated with an increase in bronchodilators. In hospital, this is usually in the form of salbutamol and atrovent nebulisers which are given regularly. In addition, controlled  oxygen therapy is given. Patients are usually prescribed steroid tablets (prednisolone 30mg per day) for 7 days.

Antibiotics are usually given if 2 or more of the following features are present: increased breathlessness, increased sputum volume or purulence, or clinical signs of pneumonia when examined by a doctor. Patients are usually admitted to hospital for an average of 5 to 7 days, depending on the severity of the exacerbation.

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Follow up after a hospital admission

After discharge from hospital, patients are reviewed by their GP or in the hospital clinic after 4-6 weeks. During this visit, their ability to cope at home, inhaler technique and understanding of their treatment is checked. In addition, they are assessed for nebuliser therapy or need for home oxygen if appropriate.

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Other considerations

It is important that inhaler technique is checked and that patients are prescribed the appropriate device, including a spacer (aerochamber) if appropriate. Patients using nebulisers should have access to a back up machine in case their nebuliser breaks down.

All patients should be encouraged to participate in a smoking cessation programme

Appropriate patients should be enrolled into an exercise/pulmonary rehabilitation programme.

Patients who are overweight or underweight should be seen by a dietician to encourage them to lose weight, or else, take food supplements if they are underweight.

Influenza vaccination is important in all COPD patients to reduce the risk of developing influenza or pneumonia.

A pneumococcal vaccine is recommended for all patients with chronic lung disease to reduce the risk of developing pneumonia.

It is important to identify and treat anxiety and depression in patients with COPD as these have been shown to be associated with this condition, especially in those patients who are severely limited in their exercise capacity due to shortness of breath. Social circumstances should also be assessed and social services involved. Help can be provided in the form of home adaptations or extra care is needed.

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Self management plan

Contact your surgery in plenty of time to ensure you don’t run out of any of your medication. AT ALL TIMES REMEMBER TO:

• Eat a varied diet – you may find that eating small amounts more often is helpful

• Drink adequate fluids (approx 2-3 litres a day) especially in hot weather

• Try to do some exercise every day – remember ‘if you don’t use it, you’ll lose it!’

• Plan ahead and allow enough time to do things

• Watch the weather forecast – for hot weather get your fans out ready. For cooler and windy weather remember to wear a muffler over your face if walking outside

• Avoid going out at all when it is very cold

• Avoid people with colds

WORSENING COPD:

Steroid Tablets: A course of these may be prescribed during an exacerbation and are taken in one morning dose, usually for one week.

Antibiotics: Not all exacerbations are caused by infection therefore they are not always prescribed. They may be prescribed if you have symptoms of infection such as increased breathlessness with coloured sputum and/or increased sputum volume.

WARNING SIGNS:

• Increased sputum production

• Change of sputum colour to green/brown

• Increased breathlessness or cough

WHAT SHOULD I DO?

• If you have increased breathlessness but no change in sputum, use your short acting bronchodilator regularly

• If no improvement in 24 hours or getting worse, start steroid tablets

• If your sputum changes colour or increases in amount commence antibiotics

• Do not stop any of your usual medicines

• If there is no improvement in 2-3 days – contact your GP

 YOU MAY BE HAVING A SEVERE ATTACK IF:

• Your symptoms are getting worse

• You are very short of breath with no relief from your inhalers

• You develop chest pains

• You have a high fever·

• You have a feeling of agitation, panic, drowsiness or confusion

RING YOUR EMERGENCY GP OR 999 FOR AN AMBULANCE

Surgery

In patients with severe or advanced COPD, operative procedures may be beneficial in carefully selected patients. These patients are usually assessed in a specialist hospital (patients from West Middlesex hospital are referred to the Brompton hospital) for assessment and treatment. The types of surgical procedures available can be summarised as follows:

1. Bullectomy. A bulla is a large pocket of air which develops from damaged lung tissue and is surrounded by a thin membrane. The bulla does not take part in process of breathing or respiration, and compresses the surrounding normal lung tissue, so it is not able to function as well. This bulla can be removed by surgery, thus allowing the surrounding lung to expand. The operation is suitable for those patients in whom the carbon dioxide level is normal and FEV1 is less than 50%.

2. Lung volume reduction surgery- usually carried out in patients with advanced COPD who have severe exercise limitation. Put simply, the diseased areas of emphysematous lungs in the upper portions of each lung are removed at surgery, so that the remaining normal lung tissue can expand and function normally. Usual criteria include FEV1 greater than 20%, dominant upper lobe emphysema on CT scan, TLCO (gas transfer) greater than 20%, carbon dioxide level of less than 7.3 kPa. In some circumstances when the patient is not suitable for an operation, this procedure can be carried out using a bronchoscope (camera) which is inserted into the lungs, with similar results.

3. Lung transplant- usually carried out in patients with advanced COPD who have progressive disease despite maximal treatment. Assessment of suitable patients is important due to complications of surgery. Usual criteria include FEV1 less than 25% and/or carbon dioxide level of less than 7.3 kPa  and/or right heart failure (cor pulmonale), equally distributed emphysema throughout the lungs, and pulmonary hypertension. The age limit for a single lung transplant is usually 65 years. The operation restores up to 70% predicted exercise capacity and normal resting oxygen levels, but the patient needs to take anti-rejection medication indefinitely, and there are significant post operative complications such as infection and rejection of the transplant.

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COPD services at West Middlesex hospital

Early COPD discharge scheme - patients admitted with COPD who have improved after hospital admission, but still require nebulisers and/or oxygen for a few days, can be discharged home early using the early COPD discharge scheme. These patients can be managed at home with nebulisers and oxygen, with a team of community matrons who visit them on a daily basis for a week to ensure they are improving.

Safe COPD discharge care bundle- West Middlesex hospital, working with Imperial college and CLAHRC (collaboration for applied health research and care), has been piloting a safe discharge COPD care bundle since May 2010. This consists of a checklist which is completed every time a patient with COPD is discharged. The checklist is designed to ensure that smoking cessation advice is given to current smokers, and inhaler technique is checked and demonstrated so that patients are using their inhalers correctly. Written information about COPD in the form of the British lung foundation booklet is given to each patient which contains useful information on self management and an oxygen alert card, which warns healthcare professionals not to use too much oxygen when patients are admitted to hospital. In addition, after discharge, patients receive a phone call 3 days after they have left hospital to ensure that they are continuing to improve and managing at home. Finally, all patients are given a date for review in the chest clinic within 4 weeks of discharge, prior to discharge or within 3 days of discharge.

Nebuliser assessments- patients with severe COPD who remain breathless despite maximal treatment are given a trial of nebuliser to see if this makes them less breathless and if it improves their exercise capacity. This is carried out by the respiratory nurse specialist.

Oxygen assessments - if patients have reduced levels of oxygen in their blood and remain short of breath despite their usual treatment, they are assessed for home oxygen. This is usually done by the respiratory nurse specialist.

Acute non invasive ventilation for COPD exacerbations presenting with respiratory failure- patients with COPD who develop respiratory failure due to an exacerbation (decreased oxygen levels and raised carbon dioxide levels due to difficulty in breathing), are treated with a bedside non invasive ventilator machine which is applied using a mask and provides respiratory support to the patients on the ward. Patients usually use this form of treatment for 3-5 days and this is weaned off as their condition improves.

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Guide to terms

An exacerbation of COPD is an acute severe worsening of the symptoms of COPD. Patients can present with worsening breathlessness, cough and/or sputum, beyond the usual day to day variation in symptoms. It may require a change in the patient’s usual treatment.  The top two causes of an exacerbation are infection of the airways or lungs and air pollution. In one-third of all COPD exacerbation cases, however, the cause cannot be identified.

Prednisolone is a synthetic corticosteroid drug that is used to treat inflammatory diseases such as asthma and COPD.  In these conditions, it is used to treat a flare up of the condition, and is usually given for 1-2 weeks in COPD, and a maintenance dose of steroids is not recommended. You may be given six very small tablets to take (each tablet is 5mg) to take on a daily basis to treat the exacerbation.  

Salbutamol is a short-acting β₂ (beta 2) -adrenergic receptor agonist drug used for the relief of bronchospasm (narrowing of the airways) in conditions such as asthma and COPD. It is usually given by the inhaled route and causes relaxation and dilation of bronchial smooth muscle in the airway walls. This causes the airways to open up to allow air to enter and leave more easily. This is usually given through a metered dose inhaler (MDI) or a nebulizer. The maximal effect of Salbutamol can take place within five to twenty minutes of dosing, though some relief is immediately seen. The most common side effects are of fine tremor, nervousness, headache, and palpitations. Other symptoms may be tachycardia, (rapid heart rate).

Ipratropium (atrovent) is an anticholinergic drug. It works by blocking specific  receptors (muscarinic cholinergic receptors) in the smooth muscles of the bronchi in the lungs. This opens the bronchi, and provides relief of breathlessness in conditions such as COPD and asthma. Side effects include dry mouth, skin flushing, tachycardia, acute angle ocular glaucoma, nausea, palpitations and headache. In COPD, atrovent is usually given through a metered dose inhaler (MDI) device if symptoms are mild and the patient needs only occasional treatment for relief of symptoms. In acute exacerbations, it is given by nebuliser.

Salmeterol is a long-acting beta 2 –adrenergic receptor agonist drug that is currently prescribed for the treatment of COPD and asthma. The main difference of salmeterol to salbutamol is that the duration of action lasts approximately 12 hours in comparison with 4–6 hours of salbutamol.

Formoterol is a long-acting beta 2adrenergic receptor agonist (LABA) used in the management of asthma and COPD. It has an extended duration of action (up to 12 hours) compared to short-acting β₂ agonists such as salbutamol, which are effective for 4–6 hours. It works faster than salmeterol. It works by relaxing the bronchial smooth muscle and causing dilation of the airways.

Seretide is a combination inhaler consisting of fluticasone (an inhaled corticosteroid which reduces inflammation) and salmeterol (which dilates the airways). It is used in the management of patients with asthma and COPD and help to relievethe symptoms of coughing, wheezing and shortness of breath.

Symbicort is a combination inhaler containing budesonide (an anti-inflammatory corticosteroid) and formoterol (a rapid and long lasting bronchodilator, which opens up the airways) used in the management of COPD and asthma.

Tiotropium (Spiriva) is a long-acting, 24 hour, anticholinergic bronchodilator used in the management of COPD. It is usually taken once a day and its effects last all day. It helps to open up the airways and give relief of breathlessness.

Theophylline is a drug used in the treatment of respiratory diseases such as asthma and COPD. The main actions of theophylline include relaxing bronchial smooth muscle, thus causing dilation of the airways. It also has some anti-inflammatory effects.

Nicotine replacement therapy (NRT) is used to help to reduce the urge to smoke that most smokers have in the early days and weeks after quitting, rather than remove them totally. It allows a more comfortable exit from the smoking habit. NRT however is best used with some form of support, ideally from someone who knows something about smoking cessation. It comes in many formulations such as a nicotine patch, inhaler, lozenge, nasal spray, and sublingual tablet, and has side effects depending on the type of product used. For example, nicotine gum can cause jaw pain and hiccoughs, while the nasal spray causes nasal/sinus irritation and a runny nose.

Bupropion (Zyban) was initially researched and marketed as an antidepressant drug, but was subsequently found to be effective as a smoking cessation aid. Initially it was thought to cause seizures in patients with epilepsy, but at the recommended dose the risk of seizures is comparable to that observed for other antidepressants. The common adverse effects are dry mouth, nausea, insomnia, tremor, excessive sweating and tinnitus. It is given as a tablet, and is as effective as NRT.

Varenicline(Champix) is a prescription medication used to treat smoking addiction. It is a nicotinic receptor partial agonist drug and it both reduces cravings for and decreases the pleasurable effects of cigarettes and other tobacco products. Side effects include depression and suicidal thoughts. Varenicline has been shown to be superior to NRT and bupropion. It is usually given for twelve weeks. If smoking cessation has been achieved, it may be continued for another twelve weeks. Varenicline has not been tested in those under 18 years old, or pregnant women, and therefore is not recommended for use by these groups. Women currently breastfeeding should also avoid this product, since Varenicline may pass into the breast milk.

A mucolytic agent  is an agent which reduces the thickness of sputum so that it can be coughed up more easily. It is useful in patients with COPD who have chronic sputum production.It is usually given for a month, and is continued if there is evidence of benefit.

Emphysema is a long-term, progressive disease of the lungs that primarily causes shortness of breath. It is the result of destruction of the lung tissue by continued smoking and is generally irreversible. Emphysema is called an obstructive lung disease because the destruction of lung tissue around smaller sacs, called alveoli, makes these air sacs unable to hold their functional shape on breathing out. This causes the airways to become narrowed.

Chronic bronchitis is a chronic inflammation of the medium-size airways (bronchi) in the lungs. It is defined clinically as a persistent cough that produces sputum (phlegm) and mucus, for at least three months in two consecutive years. Smoking is the most common cause.

Cystic fibrosis is a genetic disease which affects the entire body, causing progressive disability and often early death. It causes shortness of breath, frequent lung infections, sinus infections, poor growth, and diarrhea. It is usually detected in childhood.

Bronchiectasis is a condition characterized by localized, irreversible dilation of part of the airways (bronchi) in the lung. It is classified as an obstructive lung disease. Involved bronchi are dilated, inflamed, and easily collapsible, resulting in airflow obstruction, and impaired clearance of secretions. Bronchiectasis is associated with a wide range of disorders, but it usually results from severe bacterial infections.

A chronic disease is a disease that is long-lasting or recurrent.

A bronchus is a passage of airway in the respiratory tract that conducts air into the lungs.

Airway obstruction is a condition characterized by narrowing of the smaller airways which reduces the amount of air inhaled in each breath. Airway obstruction can be measured using a special medical device called a spirometer.

Pulmonary hypertension refers to an increase in blood pressure in the pulmonary artery, pulmonary vein or pulmonary capillaries, which form a network of blood vessels within the lungs. This can lead to shortness of breath, dizziness, fainting and other symptoms, all of which are made worse by exertion. Pulmonary hypertension has a number of causes, and severe disease can cause a markedly decreased exercise tolerance and right heart failure.

Heart failure is due to the inability of the heart to supply sufficient blood flow to meet the body's needs. Common causes of heart failure include heart attacks, high blood pressure, and abnormalities of the valves of the heart. Symptoms of heart failure include shortness of breath, (typically worse when lying flat, which is called orthopnoea), ankle swelling, tiredness and reduced exercise capacity.

Cor pulmonale is an enlargement of the right ventricle (chamber) of the heart as a response to increased resistance or high blood pressure in the lungs. If untreated, this can lead to failure of the right side of the heart.

The pulmonary airway comprises those parts of the respiratory system through which air flows. It begins at the nose and mouth, and terminates in tiny breathing sacs called alveoli. From the mouth or nose, inhaled air passes through the pharynx into the trachea, where it separates into the left and right main bronchi at the carina. The main bronchi then branch into large bronchioles, one for each lobe of the lung. Within the lobes, the bronchioles further subdivide some twenty times, ending in clusters of alveoli, where oxygen from the air is absorbed, and the waste gas, carbon dioxide is expelled from the lungs.

Pulmonary rehabilitation is a rehabilitation programme that is specifically structured for ill patients with chronic respiratory problems whose pulmonary function has decreased, even after medical treatment. It is also for patients who remain symptomatic despite medical treatment. The programme consists of physical (exercise) therapy, and there is usually input from a physiotherapist, dietician, social worker, respiratory nurse and sometimes a doctor, all of whom also provide education about COPD. It is usually carried out twice weekly for 6-8 weeks, and has been shown to increase quality of life, improve exercise capacity, reduce hospital admissions and reduce length of hospital stay if admitted.

Arterial blood gas - this is when an arterial blood sample is taken from the wrist, usually using a small needle and syringe. It allows doctors to measure the amount of oxygen and carbon dioxide in the blood. This is important to help doctors decide how to manage patients who are admitted to hospital with respiratory failure, and also in deciding which COPD patients need oxygen at home.

A CT scan is a special machine that uses computers to generate a three dimensional image of the inside of an object from a large series of two-dimensional X-ray images taken around a single axis of rotation. It allows doctors to look at the inside of your lungs in more detail than a simple chest X-ray.

A Pulse oximeter - is a small medical device that indirectly monitors the oxygen saturation (amount of oxygen) of a patient's blood, by putting a small portable probe on the patient’s finger. Most monitors also display the heart rate. They can be used for home blood-oxygen monitoring.

Right heart failure- occurs when the right sided chambers of the heart are dilated or cannot contract normally, because there is back pressure of blood due to build up of pressure in the blood vessels of the lungs. This causes back pressure on the right side of the heart. Physical examination usually reveals swelling of the legs and abdomen, and enlargement of the liver. The neck veins are also distended due to the pressure of blood in them (jugular venous pressure).

Polycthaemia - refers to an increase in the number of red blood cells in the blood. There are a number of causes of this, including conditions that cause a shortage of oxygen in the blood such as COPD. In this situation, the bone marrow produces more red blood cells in order to carry the maximum amount of oxygen in the blood and around the body where oxygen is used.

Bronchodilators - these are drugs that dilate the airways (bronchi and bronchioles), and thus increase airflow into and out of the lungs. They are useful for treating obstructive lung diseases such as asthma and COPD.  Bronchodilators are either short-acting or long-acting. Short-acting medications provide quick or "rescue" relief from acute bronchoconstriction (narrowing of the airway). Long-acting bronchodilators help to control and prevent symptoms. The three types of prescription bronchodilating drugs are β2 (beta-2)-agonists (short- and long-acting), anticholinergics (short-and lon-acting), and theophylline (long-acting).

kPa – a kilopascal (=1000 pascals) is a unit of pressure. It can be used as a unit of measurement of how much of a particular gas, such as oxygen or carbon dioxide, is present is a blood sample.

Non invasive ventilation (NIV) – this is a method of providing respiratory support to patients with respiratory failure by using a small portable bed side ventilator that is applied using a face mask fitted around the patient’s face. This works by giving an extra amount of air to the patient every time the patient breaths in, and thus helps to improve the patient’s ventilatory (breathing) effort. This helps to increase the oxygen level and reduce carbon dioxide levels in the blood. An advantage of NIV is that the patient remains conscious throughout and this form of treatment can be given on the general ward. This type of ventilation avoids the need to insert a tube into the main airway (trachea) while the patient is unconscious on a ventilator in the intensive care unit. 

A metered-dose inhaler (MDI) is a device that delivers a specific amount of medication to the lungs in the form of a short burst of aerosolized medicine that is inhaled by the patient. It is the most commonly used delivery system for treating asthma and COPD and other respiratory diseases. The medication in a metered dose inhaler is most commonly a bronchodilator or cortcosteroid or a combination of these drugs. It is important that the device is used correctly if the patient is to benefit from this. In COPD, patients are often prescribed a spacer (areochamber) to use with the MDI, so that they use the MDI correctly and inhale the maximum amount of drug into their lungs.

A spacer is an add-on device used to increase the ease of administering aerosolized medication from a metered-dose inhaler (MDI). The spacer is a small tube between the MDI and the patient’s mouth, allowing the patient to inhale the medication by breathing in slowly and deeply for approximately 5 breaths. The back end of the chamber is closed off by a back-piece. After removing the MDI’s cap, the MDI is inserted into the back-piece. The front part of the chamber is closed off by a mouthpiece that goes onto the patient’s mouth. To administer the medication, the patient brings the mouthpiece to the face and depresses the metered-dose inhaler once, resulting in the release of one dose of medication. The medication from the MDI is then briefly suspended in the spacer’s chamber while the patient inhales the aerosolized medication by breathing in and out deeply slowly.

Different types of oxygen cylinders