6. COPD and Infection Flashcards
What is chronic obstructive pulmonary disease?
A chronic, slowly progressive disorder characterised by airflow obstruction, which does not change markedly over several months.
How are FVC and the FEV1/FVC ratio affected in COPD?
Normal FVC but reduced FEV1/FVC ratio.
How many people in the UK are affected by COPD?
3.7 million.
How many deaths are caused by COPD in the UK?
30000.
How many hospital inpatient days a year does COPD account for?
1 million.
What is COPD commonly caused by?
Abnormal inflammatory response of the lung to noxious particles or gases, such as cigarette smoking and atmospheric pollutants.
What is a rare cause of emphysema?
Inherited deficiency of a1-antitrypsin.
What are the symptoms of COPD?
Productive cough with white or clear sputum, wheeze, breathlessness.
What are the signs of COPD?
Could be non, or hyperventilation with prolonged expiration, accessory muscles of respiration used, hyperinflation of the lungs.
What should be used in history taking to assess COPD?
The MRC dyspnoea scale.
How is a chest X ray useful in the assessment of COPD?
Not to diagnose COPD but more to rule out other causes, like cancer.
What lung function tests should be used to assess COPD?
FEV1/FVC ratio, lung volumes, loop.
What can a high resolution CT scan detect in COPD?
Emphysema.
What is the basic premise of simple spirometry?
The patient does maximum inhalation and then breathes out as far and fast as possible through a spirometer.
What can simple spirometry measure?
Lung volumes and capacities.
What will the blood gas results be for type I respiratory failure?
Increased respiratory rate, decreased pO2, normal or decreased CO2.
What will the blood gas results be for type II respiratory failure?
Increased respiratory rate, decreased pO2, increased CO2.
What is oxygen therapy given as treatment for?
Hypoxaemia.
What are the features of oxygen therapy?
It has to be used long term (16hrs/day), and portable.
What is the most useful measure in management of COPD?
Smoking cessation, even in advanced disease, it may slow down rate of deterioration.
What are the pharmacological interventions for COPD?
Bronchodilators (B2-adrenoagonists), corticosteroids (immunosuppressive), and antibiotics (shorten exacerbations if sputum is yellow/ green).
What is the purpose of oxygen therapy in COPD?
It increases blood oxygen saturation by administering oxygen.
What is pulmonary rehabilitation?
Using exercise training to increase exercise capacity.
Why is pulmonary rehabilitation needed in COPD?
COPD causes breathlessness which makes a patient less likely to exercise, this means muscles aren’t used and waste so it is even harder to exercise causing more breathlessness and it’s a viscous cycle.
When is a1-antitrypsin replacement therapy useful in COPD?
When the cause is a1-antitrypsin deficiency.
What are the co-morbidities often found in patients with COPD?
Cardiac, metabolic, nutritional, osteoporosis, anxiety/depression.
What are the normal common flora in the respiratory tract?
Viridans streptococci, neisseria species, anaerobes, candida species.
What are some of the less common normal respiratory tract flora?
Streptococcus pneumonia, streptococcus pyogenes, haemophillus influenza, pseudomonas, and E. coli.
What are the natural defences of the respiratory tract against infection?
Cough and sneezing reflex, muco-ciliary clearance mechanisms, respiratory mucosal immune system.
What are the muco-ciliary clearance mechanisms of the respiratory tract against infection?
Cilliated columnar epithelium and nasal hairs.
What are the respiratory mucosal immune system mechanisms of the respiratory tract against infection?
Lymphoid follicles of pharynx and tonsils, alveolar macrophages, secretary IgA and IgG.
What are the common upper respiratory tract infections?
Rhinitis (common cold), pharyngitis, epiglottits, laryngitis, tracheitis, sinusitis, otitis media.
What are the upper respiratory tract infections commonly caused by viruses?
Rhinovirus, coronavirus, influenza/parainfluenza, and respiratory syncytial virus.
What bacterial super-infections can be a results of sinusitis or otitis media?
Mastoiditis, meningitis, brain abscess.
What is pneumonia?
General term for inflammation of the gas-exchanging region of the lung, usually due to infection. It is infection of the lung parenchyma.
What is lobar pneumonia?
Pneumonia localised to a particular lobe of the lung.
What is the normal causative organism of lobar pneumonia?
Streptococcus pneumoniae.
What is bronchopneumonia?
Pneumonia that is diffuse and patchy. The infection starts in the airways and spreads to adjacent alveoli and lung tissue.
What are the common causative organisms of bronchopneumonia?
Streptococcus penumoniae, haemophilus influenza, staphylococcus aureus, anaerobes, and coliforms.
What is aspiration pneumonia?
Pneumonia from aspiration of food, drink, saliva, or vomit..
What are the common causative organism of aspiration pneumonia?
Oral flora and anaerobes.
What is interstitial pneumonia?
Inflammation of the intersticium of the lung.
What is chronic pneumonia?
Inflammation of the lungs that persists for an extended period of time.
What are the common bacteria of community acquired pneumonias?
Streptococcus pneumoniae, haemophilus influenza, klebsiella pneumoniae.
What are the atypical bacteria of community acquired pneumonias?
Chlamydia pneuophilia, mycoplasma pneumoniae, legionella pneumophilia.
What is the common profile of bacteria causing hospital acquired pneumonia?
Gram negative enteric bacteria.
What are the common bacteria causing hospital acquired pneumonia?
Pseudomonas, staphylococcus aureus, MRSA.
What are the associated features of pneumonia caused by streptococcus penumoniae?
Elderly, co-morbidities, acute onset, high fever, pleuritic chest pain.
What are the associated features of pneumonia caused by haemophilus influenze?
COPD.
What are the associated features of pneumonia caused by legionella pneumophilia?
Recent travel, younger patient, smokers, illness, multi-system involvement.
What are the associated features of pneumonia caused by mycoplasma pneumoniae?
Young, prior antibiotics, extra-pulmonary involvement.
What are the associated features of pneumonia caused by staphylococcus aureus?
Post viral, intra-venous drug user.
What are the associated features of pneumonia caused by chlamydia pneumophilia?
Contact with birds.
What are the associated features of pneumonia caused by coxiella?
Animal contact, namely sheep.
What are the associated features of pneumonia caused by klebsiella pneumoniae?
Thrombocytopenia, leucopenia.
What are the associated features of pneumonia caused by S. milleri?
Dental infections, abdominal source, aspiration.
What are the common symptoms of pneumonia?
Malaise, fever, and a productive cough - sputum clear, purulent (yellow/ green), rusty coloured (little blood), or stained with lots of blood. Pleuritic chest pain and breathlessness.
What are the chest signs of pneumoniae?
Bronchial breath sounds, crackles, wheeze, dullness to percussion, reduced vocal resonance.
What counts as hospital acquired pneumonia?
Pneumonia occurring 48hrs after hospital admission.
What percentage of hospital acquired infections does pneumonia make up?
15%.
Which patients particularly is hospital acquired pneumonia common in?
Ventilated or post surgical.
How can the severity of pneumonia be assessed?
Using the CURB 65 score.
What are the features of a CURB 65 score?
C - new mental confusion U - urea >7mmol/L R - respiratory rate >30/minute B - blood pressure systolic <90mmHg or diastolic <60mmHg Aged 65 or over.
What are the consequences of a CURB 65 score of 2 or more?
Requires hospital admission.
What samples can be collected to investigate pneumonia?
Sputum, nose and throat swabs, endotracheal aspirates, broncho alveolar lavage fluid, open lung biopsy, blood culture (before antibiotics), urine, serum.
What are the categories of microbiological investigation for pneumonia?
Macroscopic, microscopic, culture, PCR, antigen detection, and antibody detection.
What are the macroscopic investigations of pneumonia?
Look at sputum, is it purulent or blood stained?
What are the microscopic investigations of pneumonia?
Gram staining and acid fast test.
What do culture investigations of pneumonia look for?
Causative bacteria or virus.
What do PCR investigations of pneumonia look for?
Respiratory viruses.
What antigens can be detected in pneumonia investigations?
Legionella.
How can antibodies be detected in pneumonia investigations?
By serology.
What are the common opportunistic pathogens causing pneumonias in immunosuppressed hosts?
Virulent infection with common organism or infection with opportunistic pathogen: viruses - cytomegalovirus (CMV), bacteria - mycobacterium avium intracellular, fungi - aspergillus, candida, pneumocystic jiroveci, or protozoa - cryptosporidia, toxoplasma.
How are pneumonia managed?
Oral fluid/ IV fluids if severe to avoid dehydration. Ant-pyretic drugs to reduce fever and malaise. Stronger analgesic to deal with pleuritic pain. Oxygen is there is cyanosis. Antibiotics depending on type of pneumonia.
What is the common antibiotic used for community acquired pneumonia and why?
Penicillin or related antibiotics are target organism is normally pneumococcus.
What is the common antibiotic used for hospital acquired pneumonia and why?
Gram negative antibiotics like co-amoxiclav IV, as the target organism is likely gram negative.
What are the possible outcomes for pneumonia?
Resolution with possible organisation (fibrous scarring), or complications like lung abscess, bronchiectasis (airways widened), or empyema (pus in pleural cavity).
How can pneumonia be prevented?
With immunisation with the flu vaccine (annually to high risk patients), or pneumococcal vaccine (two vaccines). With chemoprophylaxis - oral penicillin/erythromycin to patients with higher risk of lower respiratory tract infections.
