Respiratory Flashcards
What is an ABG?
Measures blood gas tension values of arterial PO2 and PCO2 and blood’s pH
Arterial O2 saturation can be determined
Requires a small volume of blood be drawn from radial artery with syringe and thin needle
Sometimes femoral artery or arterial catheter
What are the indications for an ABG?
- Respiratory failure
- Identification of acid-base disorders
- Any severe illness which may lead to a metabolic acidosis: cardiac/liver/renal/multiorgan failure, hyperglycaemic states in DM, sepsis, burns, poisons/toxins
- Ventilated patients
- Sleep studies
- Severely unwell patients - affects prognosis
What are the possible complications of an ABG?
- Local haematoma
- Arterial vasospasm
- Arterial occlusion
- Air or thrombus embolism
- LA anaphylactic reaction
- Infection at puncture site
- Needle stick injury to healthcare professional
- Vessel laceration
What is aspergillus lung disease?
Lung disease associated with Aspergillus fungal infection
Summarise the epidemiology of aspergillus lung disease
Uncommon
Mainly occurs in elderly and immunocompromised
Explain the aetiology of aspergillus lung disease
Inhalation of Aspergillus spores can produce 3 different clinical pictures:
1. Aspergilloma - growth of an A. fumigates mycetoma ball in pre-existing lung cavity (eg post-TB, old infarct or abscess)
- Allergic bronchopulmonary aspergillosis (ABPA) - colonisation of airways by Aspergillus –> IgE/G-mediated immune responses; occurs in asthmatics; release of proteolytic enzymes, mycotoxins and antibodies –> airway damage + central bronchiectasis
- Invasive aspergillosis - invasion of aspergillus into lung tissue and fungal dissemination in immunosuppressed patients
What are the risk factors for aspergillus lung disease?
Asthma
CF
Elderly
Immunocompromised
What are the presenting symptoms of aspergillus lung disease?
Aspergilloma:
Asymptomatic
Haemoptysis - potentially massive
ABPA:
Difficult to control asthma
Recurrent episodes of pneumonia w wheeze, cough, fever, and malaise
Invasive aspergillosis:
Dyspnoea
Rapid deterioration
Septic picture
What are the signs O/E of aspergillus lung disease?
Tracheal deviation (only w v large aspergillomas) Dullness in affected lung Reduced breath sounds Wheeze (in ABPA) Cyanosis (in invasive aspergillosis)
How is aspergillus lung disease investigated?
Aspergilloma:
- CXR - upper zone round mass w crescent of air around
- CT/MRI if CXR unclear
ABPA:
- Immediate skin test reactivity to Aspergillus antigens
- Eosinophilia
- Raised total serum IgE
- Raised specific serum IgE and IgG to A. fumigatus
- CXR
- CT
- Lung function tests
Invasive aspergillosis:
- Culture/histo or bronchoalveolar lavage fluid/sputum - Aspergillus
- Chest CT - nodules surrounded by ground-glass appearance (halo sign)
What does a CXR of ABPA show?
Transient patchy shadows
Collapse
Distended mucous-filled bronchi
What does a CT of ABPA show?
Lung infiltrates
Central bronchiectasis
What do lung function tests in ABPA show?
Reversible airflow limitation
Reduced lung volumes/gas transfer
What does a CXR of aspergilloma show?
Round mass with a crescent of air around it in upper zones
What does a chest CT of invasive aspergillosis show?
Nodules surrounded by ground-glass appearance (halo sign)
Due to haemorrhage into tissue surrounding fungal invasion
What is asthma?
Chronic inflammatory airway disease characterised by variable reversible airway obstruction, airway hyper-responsiveness and bronchial inflammation
Summarise the epidemiology of asthma
10% of children
5% of adults
Increasing prevalence
Explain the aetiology of asthma
Genetic factors:
FHx
Atopy
Environmental factors: House dust mites Pollen Pets Cigarette smoke Viral RTIs Aspergillus fumigatus spores Occupational allergens
What are the presenting symptoms of asthma?
Recurrent episodes
Wheeze
SOB
Cough (worse in morning and at night)
What are the signs O/E of asthma?
General inspection: May be normal Nasal polyposis Tachypnoea Use of accessory muscles Prolonged expiratory phase Hyper-inflated chest
Auscultation:
Wheeze (polyphonic)
What are the precipitating factors of asthma?
Cold Viral infection Drugs - B blockers, NSAIDs Exercise Emotions
How is asthma investigated?
- FEV1/FVC ratio <80% of predicted
- FEV1 <80% of predicted
- Reduced peak expiratory flow rate
- CXR - normal or hyper-inflated
- FBC - normal or raised eosinophils and/or neutrophilia
What are the possible complications of asthma?
Exacerbations - asthma attacks
Airway remodelling
Oral candidiasis, dysphonia, and oesophageal candidiasis secondary to ICS use
What is bronchiectasis?
Lung airway disease characterised by chronic bronchial dilation, impaired mucociliary clearance and frequent bacterial infections
Summarise the epidemiology of bronchiectasis
Most often arises initially in childhood
Incidence has decreased with use of ABx
1/1000 per year
Explain the aetiology of bronchiectasis
Chronic lung inflammation –> fibrosis + permananet dilation of bronchi –> mucus pooling –> predisposes to further cycles of infection, damage, and fibrosis of bronchial walls
Causes:
Idiopathic (50%)
Post-infections - eg pneumonia, whooping cough, TB
Host-defence defects - eg Kartagener’s syndrome, CF
Obstruction of bronchi - eg foreign body, enlarged LNs
GORD
Inflammatory disorders - eg RA
What are the presenting symptoms of bronchiectasis?
Productive cough w purulent sputum or haemoptysis
Breathlessness
Chest pain
Malaise
Fever
Weight loss
Symptoms usually begin after acute respiratory illness
What are the signs O/E of bronchiectasis?
Clubbing
Coarse crepitations (usually at lung bases) that shift with coughing
Wheeze
How is bronchiectasis investigated?
Sputum:
Culture and sensitivity
CXR: Dilated bronchi - tramline shadows (parallel lines from hilum to diaphragm) Fibrosis Atelectasis Pneumonic consolidations May be normal
High-res CT:
Best diagnostic method
Dilated bronchi w thickened walls
How is bronchiectasis managed?
Conservative:
Maintain hydration
Flu vaccination
Physiotherapy - enable sputum and mucus clearance
Medical:
Acute exacerbation - 2 IV ABx which cover Pseudomonas aeruginosa
Prophylactic ABx w >3 exacerbations/yr
ICS eg fluticasone - to reduce inflammation and sputum volume
Bronchodilators
Surgical:
Bronchial artery embolisation - if life-threatening haemoptysis
Localised resection
Lung/heart-lung transplantation
What are the possible complications of bronchiectasis?
Life-threatening haemoptysis Persistent infections Empyema Respiratory failure Cor pulmonale Multi-organ abscesses
What is the prognosis of bronchiectasis?
Most patients continue to have symptoms after 10 years
Which organisms commonly cause bronchiectasis?
Pseudomonas aeruginosa Haemophilus influenzae Staphylococcus aureus Streptococcus pneumoniae Klebsiella Mycobacteria
What is extrinsic allergic alveolitis?
Interstitial inflammatory disease of the distal gas-exchanging parts of the lung
AKA hypersensitivity pneumonitis
Summarise the epidemiology of extrinsic allergic alveolitis
Uncommon
2% of occupational lung disease
50% of reported cases affect farm workers
Geographical variation
Explain the aetiology of extrinsic allergic alveolitis
Inhalation of antigenic dusts induce a hypersensitivity response in susceptible individuals
Antigenic dusts include microbes and animal proteins
Eg
Farmer’s Lung - mouldy hay containing thermophilic actinomycetes
Pigeon Fancier’s Lung - blood on bird feathers and excreta
Maltworker’s Lung - barley/maltings containing Aspergillus clavatus
What are the risk factors for extrinsic allergic alveolitis?
Smoking
Viral infection
Exposure to avian protein/mould/bacterial antigen
Exposure todiisocyanate
Exposure to acid anhydride antigen
Exposure to metal-working fluid
Nitrofurantoin, methotrexate, roxithomycin, rituximab
Herbal supplements with ayurvedic medicine
What are the presenting symptoms of extrinsic allergic alveolitis?
Dyspnoea Non-productive/productive cough Fever/chills Malaise Weight loss/anorexia
What are the signs O/E of extrinsic allergic alveolitis?
Acute:
Rapid shallow breathing
Pyrexia
Inspiratory crepitations
Chronic:
Fine inspiratory crepitations
Clubbing
How is extrinsic allergic alveolitis investigated?
- Bloods
FBC - neutrophilia, lymphopenia
ABG - reduced PO2 + PCO2 - Serology
- IgG to fungal/avian antigens - CXR
- often normal in acute episodes
- fibrosis in chronic - High-rest CT thorax
- patchy ‘ground glass’ shadowing and nodules - Lung function tests
- restrictive defect (low FEV1, low FVC)
- preserved or increased FEV1:FVC
- reduced TLC - Bronchoalveolar lavage
- increased cellularity
- biopsy
What is idiopathic pulmonary fibrosis?
Inflammatory condition of the lung resulting in fibrosis of the alveoli and interstitium
Summarise the epidemiology of idiopathic pulmonary fibrosis
Rare
6/100,000
More common in males
Explain the aetiology of idiopathic pulmonary fibrosis
Genetically predisposed host (e.g. surfactant protein mutations); recurrent alveolar damage results in cytokine release, activating fibroblasts, differentiating into myofibroblasts and increased collagen synthesis
Drugs can produce similar illnesses (bleomycin, methotrexate, amiodarone)
What are the risk factors for idiopathic pulmonary fibrosis?
Smoking
Occupational exposure to metal or wood
Chronic microaspiration
Animal and vegetable dusts
What are the presenting symptoms of idiopathic pulmonary fibrosis?
Gradual-onset, progressive SOB on exertion
Dry cough
No wheeze
Symptoms may be preceded by viral-type illness
What are the signs O/E of idiopathic pulmonary fibrosis?
Clubbing
Bibasal fine late inspiratory crackles
Signs of RHF in advanced disease
How is idiopathic pulmonary fibrosis investigated?
Bloods:
ABG - normal early, PO2 decreases w exercise, normal PCO2, rises in late disease
ANA/RF - 1/3 pts +ve
CXR:
Normal at presentation
Early disease - ground glass shadowing
Later disease - reticulonodular shadowing, signs of cor pulmonale, honeycombing
High-res CT:
More sensitive in early disease than CXR - ground- glass
Lung function tests: Restrictive features - reduced FEV1 and FVC, w preserved or increased FEV1:FVC Decreased lung volumes Decreased lung compliance Decreased TLC
Lung biopsy - gold standard for diagnosis
What is obstructive sleep apnoea?
A disease characterised by recurrent prolapse of the pharyngeal airway and apnoea (cessation of airflow > 10s) during sleep, followed by arousal from sleep
AKA Pickwickian Syndrome
Summarise the epidemiology of obstructive sleep apnoea
Common
5-20% of men > 35 years
2-5% of women > 35 years
Prevalence increases with age
Explain the aetiology of obstructive sleep apnoea
Occurs due to narrowing of the upper airways because of the collapse of soft tissues of the pharynx
Due to decreased tone of pharyngeal dilators during sleep
What are the risk factors for obstructive sleep apnoea?
Weight gain Smoking Alcohol Sedative use Enlarged tonsils and adenoids in children Macroglossia Marfan's syndrome Craniofacial abnormalities
What are the presenting symptoms of obstructive sleep apnoea?
Excessive daytime sleepiness Unrefreshing or restless sleep Morning headaches Dry mouth Difficulty concentration Irritability and mood changes Partner reporting snoring, nocturnal apnoeic episodes or nocturnal choking
What are the signs O/E of obstructive sleep apnoea?
Large tongue Enlarged tonsils Long or thick uvula Retognathia (pulled back jaws) Neck circumference > 42 in males/40 in females Obesity Hypertension
How is obstructive sleep apnoea investigated?
Sleep study - monitor airflow, respiratory effort, pulse oximetry and HR
Bloods - TFTs, ABG
What is pneumoconicoses?
Fibrosing interstitial lung disease
What are the risk factors for pneumoconicoses?
Occupational exposure to silica, coal, beryllium
High cumulative dose of inhaled silica or coal
Cigarette smoking
Chronic beryllium disease: glutamic acid at position 69 of the HLA-DP1 beta chain
What is presenting symptoms of pneumoconicoses?
Insidious onset SOB Dyspnoea on exertion Dry cough Black sputum (melanoptysis) Pleuritic chest pain
What are the signs O/E of pneumoconicoses?
Normal chest exam
Silicosis: decreased breath sounds, signs of RHF
Asbestosis:
Bi-basal, inspiratory crepitations
Clubbing
Signs of pleural effusion or RHF (cor pulmonale)
How is pneumoconicoses investigated?
- CXR
Simple: micronodular mottling
Complicated: nodular opacities in upper zones, micronodular shadowing, eggshell calcification of hilar LNs (characteristic of silicosis), bilateral lower zone reticulonodular shadowing and pleural plaques (in asbestosis) - CT scan - fibrotic changes
- Bronchoscopy
- Lung function tests - restrictive pattern (reduced FEV1 and FVC)
What is sarcoidosis?
A chronic gramulomatous disorder of unknown aetiology, commonly affecting the lungs, skin, and eyes.
Characterised by accumulation of lymphocytes and macrophages and the formation of non-caseating granulomas in the lungs and other organs.
What are the risk factors for sarcoidosis?
Age 20-40 years
FHx sarcoidosis
Scandinavian origin
What are the presenting symptoms of sarcoidosis?
Cough Dyspnoea Chronic fatigue Arthralgia Wheeze Rhonchi - bronchospasm Photophobia Red painful eye Blurred vision
What are the signs O/E of sarcoidosis?
Lymphadenopathy
Red eye
How is sarcoidosis investigated?
- CXR
Hilar and/or paratracheal adenopathy with upper lobe predominant, bilateral infiltrates; pleural effusions (rare) and egg shell calcifications (very rare)
2. Bloods FBC: anaemia, leukopenia Serum urea: elevated Creatinine: elevated Liver enzymes: elevated Serum Ca: elevated
- Lung function tests
Restrictive/obstructive/mixed pattern - ECG - conduction defects
- Purified protein derivative of tuberculin (PPD) - negative
What is tuberculosis?
Granulomatous disease caused by Mycobacterium tuberculosis
Summarise the epidemiology of tuberculosis
Annual mortality = 3 million (95% in developing countries)
Annual UK incidence = 6000
Asian immigrants are highest risk group in UK
What are the presenting symptoms of tuberculosis?
Primary TB: Mostly asymptomatic Fever Malaise Cough Wheeze Erythema nodosum Phlyctenular conjunctivitus
Miliary TB: Fever Weight loss Meningitis Yellow caseous tubercles spread to other organs
Post-primary TB:
Fever/night sweats
Malaise
What are the risk factors for tuberculosis?
Exposure to infection Born in Asia, Latin America, Africa HIV infection Immunosuppressive medicines: systemic CS, TNF-alpha antagonists Silicosis 30x risk Apical fibrosis
Explain the aetiology of tuberculosis
Infection by Mycobacterium tuberculosis (IC organism)
Survives after being phagocytosed by macrophages
What are the signs and symptoms of primary TB?
Mostly asymptomatic Fever Malaise Cough Wheeze Erythema nodosum Phlyctenular conjunctivitus
What are the signs and symptoms of miliary TB?
Fever
Weight loss
Meningitis
Yellow caseous tubercles spread to other organs
How is tuberculosis investigated?
- CXR: abnormal typical for TB; abnormal atypical for TB; or normal
- Sputum acid-fast bacilli smear: positive for acid-fast bacilli
- Sputum culture: positive; no growth; or other mycobacteria
- FBC: raised WBC, low Hb
- Nucleic acid amplification tests: +ve for M tuberculosis
What are the signs of symptoms of post-primary TB?
Fever Night sweats Malaise Weight loss Breathlessness Cough Sputum Haemoptysis Pleuritic chest pain Signs of pleural effusion Collapse Consolidation Fibrosis
What causes miliary TB?
Haematogenous dissemination of TB
What causes post-primary TB?
Reinfection or reactivation of TB
What is primary TB?
Initial infection may be pulmonary or, more rarely, gastrointestinal
What are the gastrointestinal signs and symptoms of TB?
Subacute obstruction Change in bowel habit Weight loss Peritonitis Ascites
What are the gastrointestinal signs and symptoms of TB?
Subacute obstruction Change in bowel habit Weight loss Peritonitis Ascites
What is pneumonia?
Infection of distal lung parenchyma
Summarise the epidemiology of pneumonia
5-11/1000
Community-acquired pneumonia is responsible for > 60,000 deaths per year in UK
What are the risk factors for pneumonia?
Age Smoking Alcohol Pre-existing lung disease Immunodeficiency Contact with patients with pneumonia
What are the presenting symptoms of pneumonia?
Fever Rigors Sweating Malaise Cough Sputum Breathlessness Pleuritic chest pain Confusion
What are the signs O/E of pneumonia?
Pyrexia Respiratory distress Tachypnoea Tachycardia Hypotension Cyanosis Decreased chest expansion Dull to percuss over affected area Increased tactile vocal fremitus over affected area Bronchial breathing over affected area Coarse crepitations on affected side
How is pneumonia investigated?
1. Bloods FBC - raised WCC U+Es LFTs Culture ABG - assess pulmonary function Film - Mycoplasma causes red cell agglutination
- CXR
Lobar or patchy shadowing
Pleural efusion
Note: Klebsiella often affect upper lobes
May detect complications, eg lung abscess - Sputum/pleural fluid - MC&S
- Urine - Penumococcus and Legionella antigens
- Atypical viral serology
- Bronchoscopy and bronchoalveolar lavage - if Penumocystis carinii pneumonia suspected, or if pneumonia fails to resolve
How is pneumonia managed?
- Assess severity using BTS guidelines
- Empirical ABx
- oral amoxicillin (0 markers)
- oral/IV amoxicillin + erythromycin (1 marker)
- IV cefurozime/cefotaxime/co-amoxiclav + erythromycin (>1 marker)
- add metronidazole if: aspiration, lung abscess, empyema
- switch to appropriate antibiotic based on sensitivity - Supportive treatment
- oxygen
- IV fluids
- CPAP, BiPAP, ITU care for resp failure
- surgical drainage for abscess/empyema - Discharge planning
If 2+ features of clinical instability present (high temp, tachycardia, tachypnoea, hypotension, low O2 sats) - high risk of readmission and mortality
Consider other causes if pneumonia not resolving
What are the possible complications of pneumonia?
Pleural effusion Epyema Localised suppuration, eg abscess - swinging fever, persistent pneumonia, copious/foul-smelling sputum Septic shock ARDS Acute renal failure
What is the prognosis of pneumonia?
Most resolve with Tx within 1-3 weeks
Severe pneumonia has high mortality
How can pneumonia be characterised?
Community-acquired Hospital-acquired/nosocomial Aspiration Pneumonia in the immunocompromised Typical Atypical (Mycoplasma, Chlamydia, Legionella)
What are the atypical pneumonia symptoms?
Headache
Myalgia
Diarrhoea/abdo pain
Dry cough
What is the CURB-65 score?
Used to assess severity of pneumonia
Confusion < 8 AMTS Urea > 7 mmol/L Respiratory rate > 30/min Blood pressure: systolic < 90mmHg or diastolic < 60mmHg Age > 65 years
How can pneumonia be prevented?
Pneumococcal vaccine
Haemophilus influenzae type B vaccine
Given to high risk groups, eg elderly, spenectomy
How can pneumonia be prevented?
Pneumococcal vaccine
Haemophilus influenzae type B vaccine
Given to high risk groups, eg elderly, splenectomy
What is pneumothorax?
Air in the pleural space
Summarise the epidemiology of pneumothorax
Annual incidence: 9/100,000
20-40yos
4x more common in males
Explain the aetiology of pneumothorax
Spontaneous:
- occurs in people w typically normal lungs
- typically in tall, thin males
- probably caused by rupture of subpleural bleb
Secondary:
- pre-existing lung disease, eg COPD, asthma, TB
Traumatic:
- penetrating injury to chest
- often iatrogenic, eg during jugular venous cannulation, thoracocentesis
What are the risk factors for pneumothorax?
Smoking FHx Tall and slender <40yo Recent invasive medical procedure Chest trauma Acute severe asthma COPD TB AIDS-related Pneumocystis jirovecii infection CF Lymphangioleiomyomatosis Birt-Hogg-Dube syndrome Pulmonary Langerhans cell histiocytosis Erdheim-Chester disease
What are the presenting symptoms of pneumothorax?
May be asymptomatic if small
Sudden-onset breathlessness
Pleuritic chest pain
Distress w rapid shallow breathing in tension pneumothorax
What are the signs O/E of pneumothorax?
No signs if small Signs of respiratory distress Reduced expansion Hyper-resonance to percussion Reduced breath sounds
Tension pneumothorax: Severe resp distress Tachycardia Hypotension Cyanosis Distended neck veins Tracheal deviation away from side of pneumothorax
How is pneumothorax investigated?
CXR:
- dark area of film w no lung markings
- fluid level may be seen if there is any bleeding
ABG: check for hypoxaemia
How is pneumothorax managed?
Oxygen
Chest-tube thoracostomy
Immediate needle decompression (tension)
Suction
What are the possible complications of pneumothorax?
Recurrent pneumothoraces
Bronchopleural fistula
What is the prognosis of pneumothorax?
20% have another pneumothorax
Frequency increases w repeated pneumothoraces
What is pulmonary embolism?
Occlusion of pulmonary vessels, most commonly by a thrombus that has travelled to the pulmonary vascular system from another site
Summarise the epidemiology of pulmonary embolism
Relatively common (especially in hospitalised patients) Occur in 10-20% of patients with confirmed proximal DVT
Explain the aetiology of pulmonary embolism
Thrombus
95% arise from DVT in lower limbs
Rarely arises in right atrium (in AF patients)
Other causes of embolus: Amniotic fluid Air Fat Tumour Mycotic
What are the risk factors for pulmonary embolism?
Surgical patients Immobility Obesity OCP Heart failure Malignancy
What are the presenting symptoms of pulmonary embolism?
Depends on site and size of embolus
Small - may be asymptomatic
Moderate - sudden onset SOB, cough, haemoptysis, pleuritic chest pain
Large (or proximal) - as above + severe central pleuritic chest pain, shock, collapse, acute RHF, sudden death
Multiple small recurrent - symptoms of pulmonary HTN
What are the signs O/E of pulmonary embolism?
Small - often no clinical signs, may be some tachycardia and tachypnoea
Moderate - tachypnoea, tachycardia, pleural rub, low O2 sats despite supplementation
Massive - shock, cyanosis, signs of right heart strain (raised JVP, left parasternal heave, accentuated S2)
Multiple recurrent PE - signs of pulmonary HTN, signs of RHF
How is pulmonary embolism investigated?
Well’s Score used to determine best investigation for PE
Low probability (Wells 4 or less) - use D-dimer
High probability (Wells>4) - requires imaging (CTPA)
Also:
Bloods - ABG, thrombophilia screen
ECG - normal, tachycardia, right axis deviation or RBBB, S1Q3T3 pattern
CXR - often normal but helps exclude other diagnoses
VQ scan - shows areas of mismatch –> infarcted lung
Doppler US of lower limb - VTE
Echocardiography - may show right heart strain
How is pulmonary embolism managed?
Primary prevention:
Compression stockings
Heparin prophylaxis for those at risk
Good mobilisation and adequate hydration
If haemodynamically stable: O2 Anticoagulation w heparin or LMWH Switch over to oral warfarin for at least 3 months Maintain INR 2-3 Analgesia
If haemodynamically unstable (massive PE):
Resuscitate
O2
IV fluids
Thrombolysis with tPA considered if cardiac arrest imminent
Surgical/radiological:
Embolectomy
IVC filtres - sometimes used for recurrent PEs despite adequate anticoagulation/when CI
What are the possible complications of pulmonary embolism?
Death
Pulmonary infarction
Pulmonary hypertension
Right heart failure
What is the prognosis of pulmonary embolism?
30% mortality in those left untreated
8% mortality with treatment
Increased risk of future thromboembolic disease
What is lung cancer?
Primary malignant neoplasm of the lung
Small cell - 20%
Non-small cell - 80%
Summarise the epidemiology of lung cancer
Most common fatal cancer in the west
18% of cancer mortality worldwide
3x more common in males
What are the risk factors for lung cancer?
Smoking
Asbestos exposure
Other occupational exposure: polycyclic hydrocarbons, nickel, radon
Atmospheric pollution
What are the presenting symptoms of lung cancer?
May be asymptomatic
Primary:
Cough, haemoptysis, chest pain, recurrent pneumonia
Local invasion:
Brachial plexus invasion –> shoulder/arm pain
Left recurrent laryngeal nerve invasion –> hoarse voice and bovine cough
Dysphagia
Arrhytmias
Horner’s syndrome
Metastatic disease/paraneoplastic phenomenon: Weight loss Fatigue Fractures Bone pain
What are the presenting symptoms of lung cancer?
May be asymptomatic
Primary:
Cough, haemoptysis, chest pain, recurrent pneumonia
Local invasion:
Brachial plexus invasion –> shoulder/arm pain
Left recurrent laryngeal nerve invasion –> hoarse voice and bovine cough
Dysphagia
Arrhytmias
Horner’s syndrome
Metastatic disease/paraneoplastic phenomenon: Weight loss Fatigue Fractures Bone pain
What are the signs O/E of lung cancer?
May be NO SIGNS
Fixed monophonic wheeze (single obstruction)
Signs of lobar collapse or pleural effusion
Signs of metastases - Virchow’s node
What is COPD?
Chronic, progressive lung disorder characterised by airflow obstruction that is not fully reversible, with the following:
Chronic bronchitis - chronic cough and sputum production on most days for at least 3 months per year over 2 consecutive years
Emphysema - pathological diagnosis of permanent destructive enlargement of air spaces distal to terminal bronchioles
Summarise the epidemiology of COPD
Very common - 8% prevalence
Presents in middle age or later
More common in males
Increasingly common in females
What are the risk factors for COPD?
Smoking
What are the presenting symptoms of COPD?
Chronic cough Sputum production SOB Some wheeze Reduced exercise tolerance
What are the signs O/E of COPD?
General inspection:
Tar staining
Cyanosis
Barrel chest
Palpation:
Reduced expansion
Percussion:
Hyper-resonance
Auscultation:
Reduced air mvmt
Wheezing
Coarse crackles (hair-like)
Other:
Signs of RHF
How is COPD investigated?
Spirometry and lung function tests:
Obstructive picture - reduced PEFR, FEV1:FVC, increased lung volumes, decreased CO gas transfer coefficient
CXR: May appear normal Hyperinflation (>6 anterior ribs, flattened diaphragm) Reduced peripheral lung markings Elongated cardiac silhouette
Bloods:
FBC - increased Hb and hct due to secondary polycythaemia
ABG: hypoxia, normal/raised PCO2
ECG and echocardiogram: check for cor pulmonale
Sputum and blood cultures: useful in acute infective exacerbations
A1 antitrypsin levels (deficiency)
What are the possible complications of COPD?
Acute respiratory failure Infections Pulmonary hypertension Right heart failure Pneumothorax - secondary to bullae rupture Secondary polycythaemia
What is the prognosis of COPD?
High morbidity
3-year surivial of 90% if < 60 years, FEV1 > 50% predicted
3-year survival of 75% if > 60 years, FEV1: 40-49% predicted
What is asbestosis?
Diffuse interstitial fibrosis of the lung as a consequence of exposure to asbestos fibres
Explain the aetiology of asbestosis
Inhalation of asbestos fibres
A fibrous silicate, a naturally occurring mineral
The more asbestos inhaled, the greater the risk of developing asbestosis
What are the risk factors for asbestosis?
Cumulative dose of inhaled asbestos
Smoking (reduces ability of lung to clear asbestos fibres)
What are the presenting symptoms of asbestosis?
SOB on exertion
Dry, non-productive cough
What are the signs O/E of asbestosis?
Dyspnoea
Crackles - initially at bases
Clubbing in advanced disease
How is asbestosis investigated?
- CXR: PA and lateral
Lower zone linear interstitial fibrosis; progressively involves entire lung; pleural thickening - Lung function tests
Restrictive changes
May have obstructive picture - esp if Hx of asbestos exposure and smoking
What is mesothelioma?
An aggressive epithelial neoplasm arising from the lining of the lung, abdomen, pericardium, or tunica vaginalis
Summarise the epidemiology of mesothelioma
More common in men and white people
Typically occurs in 60-90yos
In UK, incidence increasing rapidly since 60s
Country-to-country variation due to disparities in asbestos use and regulation
Explain the aetiology of mesothelioma
Asbestos exposure
Dose-response relationship
Latency period between exposure and development of malignancy = 20-40 years
Also:
Radiotherapy
Genetic - BAP1 mutation, SV-40
What are the risk factors of mesothelioma?
Asbestos exposure
60-85 yo due to latency period (20-40 years)
Male
FHx
What are the presenting symptoms of mesothelioma?
Increasing SOB
Chest pain
Dry, non-productive cough
Constitutional: fever, fatigue, sweats, weight loss
What are the signs O/E of mesothelioma?
Laboured breathing
Diminished breath sounds (due to effusion, trapped lung, bronchial obstruction)
Dullness to percussion (effusion)
How is mesothelioma investigated?
- CXR
- unilateral pleural effusion
- irregular pleural thickening
- reduced lung volumes
- parenchymal changes, eg lower zone linear interstitial fibrosis - Chest CT
- pleural thickening and/or discrete pleural plaques
- pleural and/or pericardial effusions
- enlarged hilar and/or mediastinal LNs
- chest wall invasion and/or spread along needle tracts - Thoracentesis
- exudate
- malignant cells in pleural fluid
How is asthma managed?
- SABA - salbutamol
- SABA + ICS - salbutamol + beclomethasone
- LABA + ICS - salmeterol + beclomethasone
- Trials - theophylline, oral beta-agonists, oral leukotriene receptor agonists (Montelukast)
- Oral CS
How is an acute asthma attack investigated?
PEF
Moderate = 50-75%
Acute-severe = 33-50
Life-threatening = <33
Near fatal = raised pCO2
How is an acute asthma attack managed?
- Basic obs - HR, SpO2
- Measure and record PEF
- O2 saturation and maintain SpO2 at 94-98%
- ABG
- Serum K and glucose
Repeat ABG if PaO2 <8kPa, unless SpO2 >92%; or initial PaCO2 is normal or raised; or if patient deteriorates
How is chronic COPD managed?
- SABA or SAMA - salbutamol or ipratroprium bromide - MILD
- Add LABA or LAMA - salmeterol or tiotropium - MODERATE
- LAMA + LABA or LABA + ICS - symbicort (budesonide (ICS) and formoterol (LABA)) - SEVERE
- LAMA + LABA + ICS - VERY SEVERE
Also: Smoking cessation Annual flu vaccine Pneumoccocal vaccine Long term O2 therapy Lung volume reduction surgery
What are the long-term O2 therapy guidelines?
pO2 < 7.3kPa and one of the following:
- secondary polycythaemia
- nocturnal hypoxaemia
- peripheral oedema
- pulmonary HTN
How do you manage an infective exacerbation of asthma?
- O2
- Neb salbutamol 5mg/Neb ipratropium bromide 0.5mg
- Oral prednisolone 40-50mg + IV hydrocortisone 100mg
- IV magnesium sulphate + SENIOR HELP
- IV aminophylline
- ITU + intubation
How do you manage an infective exacerbation of COPD?
- (Blue Venturi) 24% O2
- Neb salbutamol 5mg, neb ipratropium bromide 0.5mg
- Oral prednisolone 40-50mg, IV hydrocortisone 200mg
- IV amoxicillin
- 500mg IV aminophylline
- BiPAP (NIV)
How is the severity of COPD classified?
FEV1 % > 80% - mild 50-79% - moderate 30-49% - severe < 30% very severe
What are the respiratory causes of clubbing?
Malignancy
Empyema lung abscess
ILD
CF
