COPD Flashcards
what is COPD
COPD is a preventable and treatable (but not curable) respiratory condition that is characterised by persistent respiratory symptoms and airflow obstruction.
What conditions does COPD encompass? (these are the old terms used to describe COPD)
emphysema and chronic bronchitis
what is emphysema
its a pathological term referring to loss of parenchymal (functional aka helping gas exchange aka alvioli) lung texture
what is chronic bronchiolitis
clinical term referring to cough and sputum production for at least 3 months in each of 2 consecutive yrs
modifiable risk factors of COPD
Smoking - accounts for 90% of COPD cases. cigs but also water pipe, marijuana, and other types
Occupational exposure - coal or silica dust, welding fumes, industrial chemicals etc.
Air pollution
Childhood or in-utero lung damage - maternal or passive smoking, preterm birth, severe respiratory infections.
non modiafiable COPD risk factors
Alpha-1-antitrypsin deficiency - a rare, congenital cause of COPD, present in 2% of COPD cases. It should be considered in those diagnosed under 45 years.
Asthma
what are the key COPD symptoms
cough: often productive
dyspnoea (SOB)
wheeze
a history of recurrent lower resp tract infections
nature and progression of SOB
progresses over time and worse on exertion
other symptoms of COPD
weight loss
fatigue
reduced exercise tolerance
waking at night with dyspnoea
barrel chest (hyperinflation
pursed lip breathing
in severe cases, right-sided heart failure may develop resulting in peripheral oedema
signs on physical examination
- Hyper-resonance on percussion
- End-expiratory wheeze on auscultation
- Coarse crackles
- Reduced breath sounds
What are the key investigations?
spirometry
standardised symptoms score (mMRC/ CAT: latter more detailed but less widely used)
Pulse oximetry
ABG
CXR
FBC
BMI calculation
how to use spirometry data for COPD diagnsosis
1) -post-bronchodilator spirometry to demonstrate airflow obstruction: FEV1/FVC ratio less than 70%
2) after obstruction is demonstrated:
-The severity of COPD is categorised using the FEV1*:
FEV1%= observed/ predicted value-
>80% stage 1 mild
50-79= stage 2 moderate, 30-49% stage 3 severe
<30% stage 4 very severe
3) Measuring peak expiratory flow is of limited value in COPD, as it may underestimate the degree of airflow obstruction.
4) symptoms SHOULD be present to diagnose COPD in these patients
what does CXR show
- Hyperinflation (>6 anterior ribs seen above diaphragm)
- Bullae- If large may mimic a pneumothorax
- Hyperlucent lung fields
- Flat hemidiaphragm
- can exclude lung cancer
Alpha-1-antitrypsin levels- when do we do this?
If young patient, who has never smoked
What would we see on CT for A1AT deficiency and how does this differ to COPD?
would see Emphysema in lower lobes while COPD has upper lobe emphysema
why do we do an FBC as an investigation for COPD?
Exclude secondary polycythaemia
when do we do an ABG and why
If acute exacerbation to check O2 and CO2 levels because COPD causes CO2 retention and type 2 respiratory failure
What’s the first step of MANAGEMENT and why?
Smoking cessation because its the most effective COPD management
what are the options of smoking cessation therapy
Nicotine replacement therapy -patches or as shorter acting oral forms (lozenges, chewing gum) or nasal sprays; reduces urges and withdrawal symptoms by substituting for nicotine inhaled via tobacco smoke1
oral varenicline- a nicotinic receptor partial agonist that binds less effectively than nicotine
oral buproprion (seems to be a nicotinic receptor antagonist with dopaminergic and adrenergic actions; it may work by blocking effects of nicotine, relieving withdrawal, or reducing depressed mood)
what is the most appropriate smoking cessation drug for pregnant women
NRT since varenicline and bupropion are contraindicated
Bupropion- who is this contraindicated in?
Epilepsy patients
what is the most effective smoking cessation therapy
Varenicline and combination NRT (a patch plus a short acting form)
what should be monitored in patients taking varenicline and buproprion
adverse psychological reactions
What other non-pharmacological management is there?
- Annual influenza vaccine
- One-off pneumococcal vaccine
- Pulmonary rehabilitation for people who view themselves as functionally disabled by COPD
what is the first line TREATMENT (not management) of COPD
a short-acting beta2-agonist (SABA) or short-acting muscarinic antagonist (SAMA) is first-line treatment
if breathlessness/ symptoms + exacerbations don’t settle with first line what to do?
next step is determined by whether the patient has ‘asthmatic features/features suggesting steroid responsiveness’
what are the NICE criteria used to determine whether a patient has asthmatic/ steroid features?
NOT formal asthma reversibility testing JUST consider these:
-any previous, secure diagnosis of asthma or of atopy
-a higher blood eosinophil count - note that NICE recommend a full blood count for all patients as part of the work-up
-substantial variation in FEV1 over time (at least 400 ml)
-substantial diurnal variation in peak expiratory flow (at least 20%)
what is the action if there are no asthmatic features
add a long-acting beta2-agonist (LABA) ANDDD
long-acting muscarinic antagonist (LAMA)
if already taking a SAMA, discontinue and switch to a SABA
what is the action if there are asthmatic features
LABA + inhaled corticosteroid (ICS)
IN THOSE with asthmatic features that have taken the LABA+ ICS second line, what to do if they still have exacerbations?
-offer triple therapy i.e. LAMA + LABA + ICS
-if already taking a SAMA, discontinue and switch to a SABA
definition of COPD exacerbration
An exacerbation of COPD may be defined as an event characterised by increased dyspnoea and/or cough and sputum that worsens in <14 days and may be accompanied by tachypnoea and/or tachycardia.
other relevant stable management treatments in COPD not used on everyone/ use dependent on each patient
-Oral theophylline only if failed inhaled therapies or cant use them (reduce those if antibiotics together)
-Oral prophylactic antibiotic therapy: azythromycin prophylaxis only in people that have optimal management and still have exacerbrations + CT thorax + sputum uclutre + lFTs + ECG bc risk heart
- standby medications (short course oral corticosteroids and AB) for people who have had an execerbration in last year and know how to handle this treatment
-mucolytics - if chronic productive cough and continue if it works
- phosphodiesterase-4 inhibitors (PDE-4) INHIBITORS
they can reduce exacerbrations in people that have very severe copd and lots of exacerbrations despite optimal treatment - in people with cor pulmonale: use a loop diuretic for oedema, consider long-term oxygen therapy
cor pulmonale what is it
(right sided heart failure)
features include peripheral oedema, raised jugular venous pressure, systolic parasternal heave, loud P2
Factors which may improve survival in patients with stable COPD
smoking cessation - the single most important intervention in patients who are still smoking
long term oxygen therapy in patients who fit criteria
lung volume reduction surgery in selected patients
how is an acute exacerbation managed?
24% oxygen (blue venturi mask)-
- Nebulised bronchodilators (Salbutamol & ipratropium bromide)
- Corticosteroids (Oral prednisolone for 5 days or IV hydrocortisone if clinically unstable)
- IV theophylline
- Antibiotics- (with criteria)
- NIV (BiPAP)- (with criteria)
Antibiotics- when and which ones?
- Only if evidence of infection such as green sputum or signs of pneumonia
- Amoxicillin, doxycycline or clarithromycin
When do we not give clarithromycin?
In patients with congenital long QT syndrome
NIV (BiPAP)- when?
if respiratory acidosis with high CO2 despite maximum medical treatment
pH range 7.25-7.35
most common cause of an acute exacerbation of COPD?
Haemophilus influenzae
What do we give to critically ill (including CO2 retaining) patients?
High flow oxygen → reservoir mask at 15 l/min
complications of COPD
- ACUTE EXACERbations
- cor pulmonale
- lung cancer
- reccurent pneumonia
- pheumothorax
-resp. failure
What is the reported prognosis of COPD based upon?
FEV1- significant correlation between increased FEV1 and lower risk of COPD exacerbation
