Case 10 - COPD Flashcards
What is COPD?
Airway obstruction due to inflammation of the small airways
What 2 diseases is COPD made up of?
- Chronic bronchitis
- Emphysema
What is chronic bronchitis?
What are the symptoms?
- Inflammation of the bronchi
- Cough, chest pain, headache, malaise
- Productive cough at least 3 months each year for 2 consecutive years
What is emphysema?
- Permanent dilation of the alveoli and lose elasticity
- Difficulty exhaling
- Structural changes of the alveoli
What are the exogenous causes of COPD?
- Smoking/ passive smoking
- Air pollution
- Occupational exposure: coal miners
- Biomass fuel: industrialised countries
- Recurrent pulmonary infections + TB
What are the endogenous causes of COPD?
- α1-antitrypsin deficiency
- Antibody deficiency syndrome (IgA deficiency)
- Matrix metalloproteinases
- TNF – α
- Glutathione S transferase
- Primary ciliary dyskinesia
How to classify COPD?
- GOLD 1: Mild syx: ≥ 80%
- GOLD 2: Moderate syx: 50–79%
- GOLD 3: Severe syx: 30–49%
- GOLD 4: V severe syx: < 30%
Below which FEV1/FVC ratio is there airflow limitation in patients?
<70%
What are the 2 types of emphysema?
- Panlobular (panacinar)
- Centrilobular (centriacinar)
What are the signs and symptoms of COPD?
- Chronic cough with expectoration (clear sputum) in the morning
- Dyspnoea
- Cyanosis
- Barrel chest
- Accessory muscle use
- Peripheral oedema
- Palpable liver edge
- Reduced lung expansion
- No diurnal variation
What is present on percussion of chest in COPD?
- Hyper-resonant lungs: due to hyperinflation of lungs
- Reduced lung expansion
What is present on auscultation of chest in COPD?
- Inspiratory wheeze
- Corse crackle
- Silent chest in advanced COPD
- Decreased breath sounds advanced COPD
What is the normal oxygen saturations of COPD patients?
88%-92%
If FEV1 changes are <12% post bronchodilator, what does this mean?
- Irreversible bronchoconstriction
- COPD
What are the signs of COPD on chest x-ray?
- Flattened ribs
- Flattening of diaphragm
- Hyperlucency of lungs – appear blacker
- Narrow cardiac diameter – lungs expanded so push into heart
What are the differentials for COPD?
- Asthma
- Bronchial carcinoma
- Bronchiectasis
- Congestive heart failure
What is bronchiectasis?
How to diagnose it?
- Copious purulent sputum and mid inspiration coarse crackles
- HR CT
How to conservatively manage COPD?
- Smoking cessation
- Nicotine replacement therapy
- Nicotine receptor blockers (varenicline and bupropion)
- Pneumococcal and influenza vaccination
What changes in breathing helps in COPD?
Pursed lip breathing - Breathe through nose and out slowly through lips
- Increases airway pressure
What differential would you consider in an older person presenting with asthma-like symptoms?
- Asthma differentials in older people
- Idiopathic pulmonary fibrosis
- Churg-Strauss
What differential would you consider in a younger person presenting with COPD-like symptoms?
- Alpha 1 antitrypsin deficiency
What investigations are conducted with COPD?
- CXR
- ABG: respiratory failure
- FBC: polycythaemia
- CT thorax: bullae, bronchial wall thickening
What is the treatment algorithm for COPD?
- Start SABA/SAMA then use PRN
- LABA
- FEV1 > 50% = add LABA and LAMA
- FEV1 < 50% = add LAMA, LABA, and ICS
- Triple therapy: LABA + LAMA + ICS
What are other treatment options for COPD patients?
- Theophylline: aminophyillne
- LTOT: PaO2 ≤ 55 mm Hg or SaO2 ≤ 88 % at rest
- Mucolytics: Carbocisteine
What surgical options are there for COPD patients?
- Lung volume reduction
- Lung transplant
- Bullae removal
What are the features of an acute exacerbation of COPD?
- Increased SOB
- Increased cough and wheeze
- Increase in sputum/puerility (change in colourless sputum of COPD to more yellow/green)
- Hypoxia and related confusion
What investigations are done in COPD exacerbation?
- ABG
- CXR (excludes other diagnoses and provides evidence of infection)
- FBC
- U&E
- CRP
- ECG
How to treat COPD exacerbation?
- Salbutamol and ipratropium via nebuliser
- Oxygen: Do not give 100% as it stops hypoxic drive
- Steroids: IV hydrocortisone and oral prednisolone (continued for 1-2 weeks after)
- Antibiotics (usually amoxicillin, doxycycline, or clarithromycin –
- If nebulisers and steroids don’t help, add theophylline + NIV
What is the pathophysiology of cor pulmonale?
Hypoxia -> pulmonary arterial vasoconstriction -> pulmonary hypertension -> RV hypertrophy -> RV failure
Which lung volume increases in COPD?
Residual volume and total lung capacity
What is the FEV1/FVC for restrictive disease?
What changes are there in residual volume and lung capacity?
- > 70%
- Reduced residual volume and lower total lung capacity
What is a pack year?
Number of cigarettes smoked a day/ 20 (in a pack) X number of years smoked for
What is type 1 respiratory failure?
Decreased pO2
Normal pH
What is type 2 respiratory failure (hypercapnia)?
- Decreased pO2
- Increased pCO2 >7 kPa
- Lower pH
What are the clinical features of hypercapnia?
- Dilated pupils
- Bounding pulse
- Hand flap
- Myoclonus
- Confusion
- Drowsiness
- Coma
What are the names of salbutamol inhalers?
Ventolin, airomir, salamol easi-breathe (blue inhalers)
What is the name of terbutaline inhaler?
Bricanyl
What is the name of salmeterol inhaler?
Serevent
What is the name of formoterol inhaler?
Oxis
What is the name of ipotropium bromide (SAMA) inhaler?
Atrovent
What is the name of tiotropium (LAMA) inhaler?
Spiriva
How is theophylline administered?
Modified release tablet
What are the names of inhaled glucocorticoids?
- Beclomethasone: becotide
- Fluticasone: Flixotide
- Budesonide: Pulmicort
What is the MRC dyspnoea scale?
- 0: only strenuous exercise
- 1: Level ground/walking up a slight hill
- 2: Walks slower than people of same age from dyspnoea, or has to stop for breath when walking at own pace on level ground
- 3: Stops for breath after walking 100, or after a few minutes on level ground
- 4: Too breathless to leave house
What are the causes of
metabolic acidosis?
- Increased acid production: = Diabetic ketoacidosis = Lactic acidosis = Aspirin overdose - Decreased acid excretion or loss of HCO3-: = GI loss of HCO3- :diarrhoea, ileostomy, colostomy = Renal tubular acidosis (retaining H+) - Addisions disease (retaining H+)
What are the causes of metabolic alkalosis?
- Gastrointestinal loss of H+ ions: vomiting/diarrhoea
- Renal loss of H+ ions – loop and thiazide diuretics / heart failure / nephrotic syndrome / cirrhosis / Conn’s syndrome
- Iatrogenic – addition of alkali
What are the causes of respiratory acidosis?
- Pneumonia
- Guillain Barre syndrome
- Asthma
- COPD
- Latrogenic (excessive mechanical ventilation)
What are the causes of respiratory alkalosis?
- Anxiety – often referred to as a panic attack
- Pain – causing an increased respiratory rate
- Hypoxia – resulting in increased alveolar ventilation in an attempt to compensate
- Pulmonary embolism
- Pneumothorax
- Latrogenic (excessive mechanical ventilation)
What is respiratory alkalosis?
Hyperventilation leading to more CO2 being exhaled.
- What % of oxygen does a venturi mask deliver?
- What is it used in?
- Delivers 24-60% oxygen
- COPD and when correct oxygen saturation are essential
- What % of oxygen does a non rebreathe mask deliver?
- What is the flow rate?
- How does it work?
- When is it used?
- What is the ideal saturation?
- Delivers 85-90% oxygen
- 15L flow rate
- Bag on mask with valves stopping almost all rebreathing of expired air
- Used for acutely unwell patients
- 94-98%
- What is CPAP used for?
Acute pulmonary oedema, sleep apnoea, HF, pneumonia
- What are the indications for NIV/BiPAP?
- pH <7.35, pCO2 >6.5 despite controlled oxygen therapy
- Moderate to severe breathlessness with accessory muscle use
- Respiratory rate >25/min
- Used in exacerbations of COPD (without pneumonia) and ARDS
What are the contraindications for NIV/BiPAP?
- pH <7.25
- Confusion
- Recent upper GI surgery
- Vomiting
- Fixed airway obstruction
- Life threatening hypoxemia
- Haemodynamically unstable
- How long is LTOT used for?
- What should the PaO2 be kept above?
- What are the indications?
- 15 hours a day
- 8 kPa
- Cyanosis
- Polycythaemia
- Peripheral oedema
- Raised JVP
- Oxygen saturations of 92% or less breathing air
