Resp Session 6 Flashcards
What two conditions is COPD a combination of?
Emphysema and chronic bronchitis
What is the pathogenesis of chronic bronchitis?
Inflammation in large always causes:
Remodelling and narrowing of airways
Hyper secretion of mucus and proliferation of goblet cells
Chronic productive cough and frequent infections
What is the pathogenesis of emphysema?
Terminal bronchioles and distal airspaces destroyed causing:
Loss of elastic tissue –> hyperinflation
Small airways collapsing on expiration
Bullae due to large redundant air spaces
What causes COPD?
Smoking
Alpha-1 antitrypsin deficiency (esp
What are the S/S if COPD?
Cough with sputum Purse lip breathing SoB Use of accessory muscles in breathing Tachypnoea Wheeze --> quiet breath sounds --> silent chest
What are the S/S of more advanced cases of COPD?
Silent chest Peripheral +/- central cyanosis CO2 retention flap Cor pulmonale Oedema
What are the 5 stages of the MRC dyspnoea score used to assess COPD?
- SoB on strenuous exercise only
- SoB on hurrying/walking up slight hill
- Walks slower due to SoB
- Stops for breath after walking ~100m on level ground
- Too SoB to leave house/SoB on dressing
What investigations can be used in COPD?
Spirometry CXR HRCT ABG Alpha-1-antitrypsin blood test
Why is HRCT used in investigation of COPD?
Gives detailed assessment of macroscopic alveolar destruction in emphysema, useful if considering surgery
Why is CXR mandatory in COPD investigation?
To exclude other diagnoses
What do NICE guidelines state are mild, moderate and severe levels of airflow obstruction detectable by spirometry?
Mild: FEV1 = 50-80%
Moderate: FEV1 = 30-49%
Severe: FEV1
How is COPD diagnosed?
Hx: smoker, >40 y.o. with onset of symptoms later in life, chronic productive cough, persistent and progressive SoB
AND
obstructive pattern on spirometry
How is stable COPD managed?
Smoking cessation Pulmonary rehabilitation Bronchodilators Antimuscarinics Steroids Mucolytics Dietary review Supportive Tx Long term O2 and surgery if appropriate
What is the cycle of reconditioning seen in stable COPD pts?
Feel SoB –> avoid activities that worsen SoB –> do less –> muscles weaken –> worsened SoB –> feel depressed –> avoid activities etc.
What are some of the S/E associated with treatment of stable COPD?
Beta-2 agonist: tachycardia, anxiety, hypokalaemia, tremor
Antimuscarinics: urinary difficulty, dry mouth, URT, glaucoma
Steroidal S/E
How is an acute COPD exacerbation managed?
Aim for sats of 88-92% with titrated O2 therapy
Nebulised bronchodilators
Oral steroids
Abx if blood tests indicate infection
Consider IV bronchodilator
Repeat ABG to assess need for ventilation
How can COPD generally be distinguished from asthma by using clinical features?
Pts tend to be smokers
S/S >65 y.o.
Chronic productive cough
Persistent and progressive SoB
Night time waking with cough/wheeze uncommon
Diurnal pattern/day-to-day variability uncommon
What characterises COPD?
Airflow obstruction which is usually progressive, not fully reversible and does not change markedly over several months
What are common microbial flora of the URT?
Viridans streptococci
Neisseria sp.
Candida sp.
What are URTIs most commonly caused by?
Self limiting viruses
Why can viral URTI lead to secondary bacterial infection?
Due to viral action on cilia
Give some examples of common URTIs.
Rhinitis Tracheitis Pharyngitis Sinusitis Laryngitis Otitis media
What deferences does the respiratory tract have against infection?
Nasal hairs Ciliated columnar epithelium Cough+sneeze reflexes Respiratory mucosa Lymphoid follicles of pharynx and tonsils Alveolar macrophages Secretory IgA and IgG
Give some examples of LRTIs.
Bronchitis Pneumonia Bronchiolitis Empyema Bronchiectasis Lung abscess
How does a poor swallow lead to aspiratory pneumonia?
Allows secretory pool in pharynx which can enter LRT
What is acute bronchitis?
Inflammation of medium sized airways often seen in smokers
