Respiratory 2 Flashcards
What are the main risk factors of COPD?
Smoking
enviromental factors: •Climate, air pollution, urbanisation, social class and occupation (dust & silica) also play a role
alpha 1 antitrypsin deficiency
Infections
Low birth weight
What is the diseases within COPD?
CHronic bronchitis
Emphysema
Pathophysiology of chronic bronchitis breifly?
•Increased number of mucous secreting goblet cells in bronchial mucosa due to smoke irritation
- causes: narrowing of airway, hypertrophy (increase in the size of the mucous glands-bigger), hyperplasia (more mucous)
- Ciliary dysfunction: Globlet cells also have damage/motility in cilia so mucous build up more
- Air trapping: less oxygen getting in due to mucous block and less CO2 leaving body
•Hypersecretion à immobile cilia à mucous plugs à airflow obstruction à retention of CO2 and less O2 à hypoxia + acidosis à blue bloaters
- could lead to hypoxemia and hypercepnia
- risk of developing pneumonia because mucous plug might contain hemophilus influenza or moraxella which cause infection
-
Pathophysiology of emphysema?
- structural issue
- smoking and pollutants causes phagocytosis
- this releases cytokines
- cytokines activates neutrophils due to inflammation
- neutophils starts release specifc protease elastase which breaks down elastin
- macrophages to releases proteases and chemokines which attract neutrophils that release elastases, nicotine inhibits protease inhibitors (alpha 1 antitrypsin)
- since you dnt have much alpha 1 antitrypsin to oppose elastase, elastase causes damage to the alveoli.
Complications from chronic bronchitis?
- could lead to hypoxemia and hypercepnia
- risk of developing pneumonia because mucous plug might contain hemophilus influenza or moraxella which cause infection
Function of elastin?
Helps increase the recoil of the lungs
When you inhale it is a active process but when you exhale it is passive and so the lungs recoil and go back to its normal shape
What is the function of alpha 1 antityrpsin
What happens when you are deficient in it?
it is a protease inhibitor made in the liver.
it opposes elastase
•Alpha antitrypsin deficiency
- Protein accumulates in liver meaning low levels in the lungs à cant inhibit neutrophil elastases à destruction of alveolar wall connective tissue
- 2% of UK cases of emphysema
- Usually causes COPD in < 40 y/o
Complications from emphysema?
- damage to the alveoli
- airways will narrow and wont be able to keep open due to the lack of elastin
- start to lose sA from alveoli and blows up- Destruction of septa between alveoli creating distended bullae – deceased SA
- Enlarged air spaces distal to terminal bronchiolesalso build up of Co2 leads to hypoxia and hypercepnia
• loss of elastic recoil in lungs – hold more air (elastases > anti elastases)
What are the different types of emphysema?
centriacinar- dilated pockets of air in the proximal airway
panacinar- distal airways
Distal acinar-distal alveoli can cause spontaneous pneumothorax
Epidemiology of COPD?
Approximately 3 million people in the UK are diagnosed with COPD and a suspected 2 million more may be undiagnosed.
Clinical features of COPD?
Chronic productive cough and dyspnea are the hallmarks of COPD.
Symptoms:
- Chronic cough: usually productive
- Sputum production
- Breathlessness: usually on exertion in early stages
- Frequent episodes of ‘bronchitis’: usually in the winter
- Wheeze
- Pursed lip breathing: (prevents alveolar collapse by increasing the positive end expiratory pressure)
- Bronchial sounds
What does this scan show?
CXR demonstrating COPD with hyperinflation
Investigations for COPD?
Bedside
- Observations: including pulse oximetry
- Body mass index (BMI)
- Sputum culture (if purulent)
- Arterial blood gas (if hypoxia or hypercapnia is suspected): needed in acute exacerbations or work-up for long-term oxygen therapy
- ECG (if cor pulmonale suspected)
Bloods
- Full blood count: important to assess for anaemia and polycythaemia
- Alpha-1 antitrypsin levels
Imaging
Chest x-ray (CXR):
Hyperexpanded
Flattened hemidiaphragms
Hypodense
Saber-sheath trachea
CT scan: consider performing if
Symptoms disproportionate to spirometric assessment
Alternative diagnosis suspected (e.g. bronchiectasis, fibrosis)
Lung cancer suspected or to investigate abnormalities on chest x-ray
Echocardiogram: if cor pulmonale suspected.
Management for COPD patients?
All patients with COPD should be offered education, smoking cessation, vaccinations(influenza vaccine and pneumococcal), pulmonary rehabilitation (if indicated) and pharmacotherapy (e.g. inhalers).
Drugs for COPD
Beta-receptor agonists: bind to beta receptors of the sympathetic nervous system. Causes relaxation of airway smooth muscle and subsequent bronchodilation. May be short or long-acting.
Muscarinic receptor antagonists: these drugs prevent the activation of muscarinic receptors by acetylcholine. This prevents airway smooth muscle contraction and causes bronchodilation. Can be short or long-acting.
Corticosteroids: inhaled corticosteroids work by reducing inflammation within the lungs. They are thought to reduce the number of exacerbations, improve the efficacy of bronchodilators and decrease dyspnoea in stable COPD.
Inhaler types for COPD?
- Short-acting beta-agonists (SABA): Salbutamol
- Long-acting beta-agonists (LABA): Salmeterol
- Short-acting muscarinic antagonists (SAMA): Ipratropium
- Long-acting muscarinic antagonists (LAMA): Umeclidinium / tiotropium
- Inhaled corticosteroid (ICS): Beclomethasone
- LABA-ICS: Seretide (salmeterol/fluticasone)
- LABA-LAMA: Ultibro (indacaterol/glycopyrronium)
- LABA-LAMA-ICS: Trimbow (formoterol/glycopyrronium/beclometasone
What is Pulmonary embolism?
acute/chronic occlusion of pulmonary arteries. Clot breaks off and travels to the lungs (emboli).
Occlusion maybe due to a blood clot, fat, air or tumour
What is deep vein thrombosis?
acute/chronic occlusion of deep vein(s). Commonly affects the lower limbs through the formation of a clot forms (thrombus).
Venous thromboembolism (VTE) is a term that encompasses two conditions:
Pulmonary embolism
Deep vein thrombosis
What is incidence like with PE?
increases with age–doubles everydecade after 20 years
What is the aetiology of PE?
The typical cause of PE is an emboli that arises from a DVT. The DVT itself may be provoked or unprovoked based on the same risk factors of PE (it is also a thromboembolic disease). A history of unilateral leg swelling that precedes the onset of chest pain and dyspnoea is classical for the diagnosis of PE.
What are the major risk factors of PE?
- DVT
- Previous VTE
- Active cancer
- Recent surgery (e.g. within last 2-3 months)
- Significant immobility (e.g. hospitalisation, bed-rest)
- Lower limb trauma/fracture
- Pregnancy (+ 6 weeks postpartum)
What are additional risk factors to PE?
- Combined oral contraceptive pill
- Long-distance sedentary travel (e.g. long-haul flights)
- Thrombophilia
- Obesity
- Others









