Respiratory Flashcards
FEV1/FVC ratio interpretation
> 0.70 - restrictive lung disease
<0.70 - obstructive lung disease
kCO (gas transfer per unit volume) is reduced in
Emphysema
Interstitial lung disease
kCO (gas transfer per unit) is increased in
Pulmonary haemorrhage
- SLE
- Wegener’s
- Goodpasture’s
Severity of COPD
Medical Research Council Dyspnoea Scale
MRC Dyspnoea Scale 1
Not breathless except on exertion
MRC Dyspnoea Scale 2
SOB on hurrying or walking up slight hill
MRC Dyspnoea Scale 3
Stops for breath at 100m or after a few minutes on level ground
MRC Dyspnoea Scale 4
Too breathless to leave house or getting dressed
GOLD Staging of airflow obstruction
I - mild - FEV1 >80% predicted
II - moderate - FEV1 50-80% predicted
III - severe - FEV1 30-50% predicted
IV - very severe - FEV1 <30% predicted OR FEV1 <50% with respiratory failure
Best predictor of outcome in COPD
BODE index
- FEV1
- 6 minute walk distance
- MRCDS
- BMI
Treatment for COPD - non-pharmacological
Pulmonary rehabilitation
- MDT approach
- statistically significant increase in exercise tolerance
Optimise nutrition
Vaccination
Treatment for COPD - pharmacological
Short acting bronchodilators
- beta2 - salbutamol/terbutaline
- anticholinergic - ipratropium bromide
Inhaled corticosteroids (FEV1 <50%)
Oral corticosteroids
- associated with increased morbidity and mortality
Combined treatment
Theophylline
Oxygen
NIV in COPD indication
Consider in patients with type II respiratory failure despite adequate treatment
Role of surgery in COPD
Lung volume reduction surgery
- select group of patients (very severe disease with predominantly upper lobe emphysema)
Bullectomy
- bullae >1/3 of hemithorax
Lung transplant
- 51% 5 year survival
Contraindications for NIV
Life threatening hypoxaemia
Confusion
Facial injury
Vomiting
Fixed upper airway obstruction
Inability to protect airway
Undrained pneumothorax
Haemodynamic instability
Bowel obstruction
Upper GI surgery
Initial NIV pressures
IPAP 12-16
EPAP 4-5
Repeat ABG at 1 hour
Most common cause of CAP
Streptococcal pneumonia
Most common cause of CAP in COPD
Haemophilus influenza
Moxarella also common
Most common cause of CAP in Sep-Oct
Legionella
Most common cause of CAP in winter
Staphylococcus aureus
- associated with viral infection
Most common cause of HAP
Gram-negative bacilli
Pseudomonas
Anaerobes
Respiratory causes of clubbing
ABCDEF
Abscess and asbestosis
Bronchiectasis
Cystic fibrosis
Dirty tumours (bronchiogenic carcinoma, mesothelioma)
Empyema
Fibrosing alveolitis
Causes of clubbing and crackles
FAB
Fibrosing alveolitis
Asbestosis
Bronchiectasis, bronchiogenic carcinoma
Lab investigations bronchiectasis
Sputum MCS, AFB, cytology
FBC
Serum immunoglobulins (hypogammaglobulinaemia)
Alpha-1 antitrypsin levels
Aspergillus precipitans and IgE (ABPA)
Autoantibodies (CTD)
Definitive test for bronchiectasis
HRCT
Reid classification
- cylindrical (most advanced)
- varicose
- saccular (cystic)
Bronchial thickening and dilatation
- tram tracking
Signet ring sign
Pus/fluid levels
Mucus plugging
Lack of normal tapering
Tree in bud appearance
Bronchiectasis - tests for aetiology
Cystic fibrosis
- sweat test (chloride >60mmol)
- genotyping
Kartagener’s syndrome
- nasal brushing
- electron microscopy
Tuberculosis
- tuberculin skin test
- interferon gamma release assay
Clinical features: cystic fibrosis
Young, Caucasian, short, thin, pale
Clubbing
PEG feeding
Long term vascular access
Diarrhoea
Diabetes
Clinical features: Young’s syndrome
Similar to CF
No abnormal sweat or pancreatic insufficiency
Often middle aged men
Kartagener’s syndrome: clinical features
Ciliary dyskinesia
Dextrocardia
Situs invertus
Subfertility
Sinusitis
Otitis media
Clinical features: yellow nail syndrome
Yellow nails
Pleural effusion
Lymphoedema
‘Asthma’ resistant to bronchodilators plus cough could be
Allergic bronchopulmonary aspergillosis
Treatment for bronchiectasis
Treat underlying cause
Education
Nutrition
- CF may need pancreatic enzyme replacement and fat soluble vitamin supplements
Smoking cessation
Vaccinations
Sputum clearance/physiotherapy
Prophylactic antibiotics (azithromycin)
Bronchodilators if evidence of reversibility
Steroids (inhaled and oral)
Mucolytics
- RhDNAase in CF
Surgery
Transplantation in CF
Pathogenesis of CF
Autosomal recessive
Defect in CFTR gene
CFTR gene located in all exocrine tissues
Prevents chloride moving out of cells
Dehydration of extra cellular surfaces as water drawn into cells
Thick viscous secretions
Most common mutation in CFTR gene on chromosome 7
^F508
Systems affected by cystic fibrosis
GI:
- pancreatic enzyme deficiency with malabsorption of fat and protein
- diabetes
- meconium ileus
- focal biliary cirrhosis and portal hypertension
- cholelithiasis
Reproductive:
- male subfertility -> spermatogenesis is normal
Musculoskeletal:
- osteoporosis
ENT:
- sinus disease and nasal polyposis
Organism that is CI to transplant for CF
Burkholderia cepacia complex
Conditions associated with bronchiectasis
CF
COPD
Connective tissue disease (RA)
Chronic sinusitis
IBD
Marfan’s syndrome
Main pathogens associated with bronchiectasis
Pseudomonas aeruginosa
Haemophilus influenza
Streptococcus
Complications of old pulmonary tuberculosis
Apical fibrosis
Bronchiectasis
Aspergilloma in old TB cavity
Pleural effusion/thickening
Old techniques to manage TB
Plombage - inserting inert substance into lungs to block O2 supply
Thoracoplasty - ribs resected to reduce intrathoracic volume
Phrenic nerve crush - paralyse diaphragm of affected side
Gibbus deformity
Kyphosis
Sign of spinal TB (Pott’s disease)
Mantoux testing versus interferon gamma release assay
IGRA more sensitive and specific
Management of pulmonary TB
Notifiable disease
Check LFTs, visual acuity, colour vision
Advise side effects of medication
Safety net - vomiting/jaundice
Consider Vitamin D supplementation
Commence pharmacological management:
Rifampicin (6)
Isoniazid (6)
Pyrazinamide (2)
Ethambutol (2)
Side effects of isoniazid
Hepatitis
Peripheral neuropathy
Side effects of rifampicin
Increased activity of liver enzymes - reduced effectiveness of some medications (OCP, anti-epileptics etc)
Red discolouration of secretions and urine
GI disturbance
Side effects of pyrazinamide
GI disturbance
Hepatitis
Peripheral neuropathy
Gout
Side effects of ethambutol
Optic neuritis
Crepitations in pulmonary fibrosis
May disappear if leaning forward
Unaffected by coughing
Fine late inspiratory creps
Symmetrical upper zone fibrosis pneumonic
CHARTS
Symmetrical upper zone fibrosis causes
Coal worker’s pneumoconioses
Histoplasmosis
Hypersensitivity pneumonitis
Histiocytosis X
Ankylosing spondylitis
ABPA
Radiation
Tuberculosis
Sarcoidosis
Silicosis
Symmetrical lower zone fibrosis causes
Rheumatoid arthritis
Asbestosis
Connective tissue disease
Idiopathic pulmonary fibrosis
Other (drugs, chemicals, bronchiectasis)
Symmetrical lower zone fibrosis pneumonic
RATIO
Asymmetrical pulmonary fibrosis causes
Treated TB
Malignant disease
Rheumatological causes of fibrosis
RA
SLE
Polymyositis
Dermatomyositis
Systemic sclerosis
Sjögren’s syndrome
Ankylosing spondylitis
Mixed connective tissues disease
All lower zone fibrosis apart from AS
Pnemocomioses definition
Group of chronic respiratory diseases caused by inhalation of metal or mineral particles
Pneumoconioses causing fibrosis
Coal worker’s - apical
Silicosis - apical, hilar calcification
Berylliosis - granulomatous similar to sarcoidosis
Asbestosis - lower zone with pleural plaques/mesothelioma
Granulomatous disease causing fibrosis
TB - apical, caseating granulomas
Sarcoidosis - non-caseating, may have hilar lymphadenopathy
Treatment of extrinsic allergic allveolitis/hypersensitivity pneumonitis
Acute - steroids
Chronic - avoidance of precipitating factors
Allergic/pneumonitis causes of fibrosis
Farmer’s lung - mouldy hay
Bird-fancier’s lung - pigeons
Byssinosis - cotton dust
Mushroom worker’s lung - mushroom spores
Malt worker’s lung - mouldy barley
Chemical causes of fibrosis
Metals:
- steel, brass, lead, mercury, beryllium
Chemicals:
- vinylchlorides
Poisons:
- paraquat
Iatrogenic/medication causes of fibrosis
Bleomycin
Busulphan
Cyclophosphamide
Methotrexate
Amiodarone
Nitrofurantoin
Sulphasalazine
Gold
Histological subtypes of idiopathic interstitial pneumonias
Usual interstitial pneumonia (12% steroid responsive) - IPF, asbestosis, drug toxicity, hypersensitivity, collagen vascular disease
Desquamative interstitial pneumonia (62%) - associated with smoking
Non-specific interstitial pneumonia (~60%)
Cryptogenic organising pneumonia - RA, amiodarone. Treat with steroids over 6-12 months
Respiratory bronchiolitis-associated interstitial lung disease - exaggerated bronchiole response to cigarette smoke
Acute interstitial pneumonia - Hamman-Rich syndrome
Investigations in pulmonary fibrosis
ABG - improves of lying down
FBC - eosinophils
Precipitins
ANA, RF, anti-centromere, anti-Scl70, anti-Jo1
Serum immunoglobulins
ACE
CK
Lung function tests
6 minute walk test
CXR
HRCT
ECHO
Bronchoscopy
Hamman Rich syndrome
Acute, rapidly progressive lung fibrosis (AIP)
Poor overall outcome - 6 month survival 22%
Treatment for pulmonary fibrosis
Corticosteroids
Immunosuppressives
- cyclophosphamide, azathioprine, methotrexate, cyclosporine
Anti-oxidant
- NAC
Supplemental oxygen
Lung transplantation
Anti-fibrotics rarely used
Bosentan for pulmonary hypertension
Median survival for idiopathic pulmonary fibrosis
2.8 years
Favourable subtype = NSIP
5 main respiratory manifestations of rheumatoid arthritis
Pleural effusions/pleurisy
- low glucose, RF positive
Pulmonary nodules
- upper lobe typically
Fibrotic lung disease
- from disease or treatment
Caplan syndrome
- coal worker pneumoconioses and RA
Obliterative bronchiolitis
- small airways obstruction
Main causes of transudate pleural effusions
CHAM
Congestive cardiac failure
Hypoalbuminaemia
All failures (cardiac, liver, renal)
Meig’s syndrome
Main causes of exudate pleural effusions
PINTS
Pneumonia
Infarction
Neoplastic
Tuberculosis/Trauma
Sarcoidosis/Scleroderma and other CTD
Drugs causing pleural effusion
Drug-induced lupus (quinidine, procainamide, hydralazine)
Dopamine agonists (bromocriptine)
Disease modifying antirheumatics (MTX)
Anti migraine
Antibiotics (nitrofurantoin)
Chemotherapy
Processes leading to pleural effusion
Increased hydrostatic pressure or reduced oncostatic pressure (transudate)
Increased capillary permeability (exudate)
Disruption of the lymphatic duct (chylothorax)
Infection within the pleural space (empyema)
Bleeding into the pleural space
Low glucose effusions
MEAT
Malignancy
Empyema
Arthritis
Tuberculosis
Light’s criteria for exudates
Pleural:serum albumin ratio >0.5
Pleural:serum LDH ratio >0.6
Pleural LDH >2/3 UL normal serum LDH
Pleural effusion protein concentrations
> 30g/dL - exudates
<30g/dL - transudate
Pleural effusion pH <7.2
Empyema
Pleural effusion TGs >1.3mmol/L
Chylothorax
Para-pneumonic effusions
Educative effusions that accompany ~40% of bacterial pneumonias
Can be simple or complex
Pleurodeisis mechanism
Performed medically with talc or surgically with VATS
Agents instilled into pleural cavity
Induces fibrosis of pleural space
Three components of obesity hypoventilation/Pickwickean syndrome
Obstructive sleep apnoea
Hypercapnia
Restrictive deficit on PFTs
Causes of airway obstruction in OSA
Upper airway narrowing
- obesity, macroglossia, macrognathia etc
Upper airway collapse
- excess pressure from inhalation
- nasal obstruction (rhinitis/septal deviation)
Abnormal muscle tone
Management of OSA and Pickwickian syndrome
Weight loss
Reduce/stop smoking and alcohol
CPAP (or NIV in PS with severe hypercapnia)
LTOT
Oral appliances
Surgery
Drugs
- modafenil
- fluoxetine (suppresses REM sleep)
- orlistat
Complications associated with OSA
OHS (Pickwickian syndrome)
Cardiac arrhythmias
Hypertension
- pulmonary and systemic
Stroke
MI
Increased mortality
Small horizontal scar in suprasternal notch
Mediastinoscopy scar
Think cancer investigation
Complications of tumour extension in lungs
Hoarse voice
- laryngeal nerve palsy
Stridor
Horner’s syndrome
SVCO
MSK paraneoplastic syndromes
Polymyositis
Hypertrophic pulmonary osteoarthropathy
- clubbing, pain and swelling in wrists
- all cell types but mostly squamous and adenocarcinoma
Neurological paraneoplastic syndromes
Lambert Eaton myasthenic syndrome
- antibodies against voltage-gated calcium channels
- small cell lung cancer
Proximal myopathy
Peripheral neuropathy
Cerebellar syndrome
Endocrine paraneoplastic syndromes
Hypercalcaemia
- squamous cell
- PTH-related peptide release
- treat with rehydration and bisphosphonates
SIADH
- small cell lung cancer
Ectopic ACTH secretion
- small cell lung cancer
HCG secretion
- gynaecomastia
Dermatological paraneoplastic syndromes
Thrombophlebitis migrans
Acanthosis nigrans
Erythema gyratum repens
Dermatomyositis
Histological classification of lung cancer
Non-small-cell lung cancer
75-80%
Squamous cell > adenocarcinoma > alveolar cell > large cell
Small-cell lung cancer
20-25%
Most common paraneoplastic syndromes affecting lung cancer patients
Hypercalcaemia
SIADH
Indications for surgery in patients with NSCLC
Stage I and II
Sometimes in Stage III A
Adequate lung function and comorbidities:
FEV1>2L - pneumonectomy
FEV1>1.5L - lobectomy
DLCO >80%
VO2 max >15mL/kg/min
OR
Predicted postoperative FEV1>40%
Management of NSCLC
MDT approach
Surgery offers best long-term survival
- adjuvant chemotherapy increases survival
Radical RT (I, II, or III)
Chemotherapy (III or IV)
- platinum + 3rd generation drugs
Combination RT/chemo (III)
Palliative (IV)
- RT
- chemo
- symptom control
Management of SCLC
RT and platinum based chemotherapy
Prophylactic cranial RT
Common causes of SVCO
Lung cancer
Lymphoma
Thymoma
Primary mediastinal germ cell tumours
Solid tumours with lymph node metastases
Fibrosing mediastinitis (uncommon)
Post-radiation fibrosis
Thoracic aortic aneurysm
Thrombosis
Management of SVCO
Treat underlying cause
Steroids
- may be helpful in steroid-responsive malignancies
Stent
- rapid relief of symptoms
Chemo/RT
Signs of pneumonectomy/lobectomy
Thoracotomy scar
Asymmetrical chest flattening/deformity
Tracheal deviation
- towards lesion in pneumonectomy and upper lobectomy
Displaced apex beat
- towards lesion
Reduced chest expansion
Dull percussion note
Decreased/absent breath sounds
Look for underlying cause
Posterolateral thoracotomy scar: pneumonectomy
Fluid filled cavity
Dull percussion note
Decreased/absent breath sounds
Posterolateral thoracotomy scar: lobectomy
Compensatory hyperinflation of ipsilateral lobes - difficult to interpret clinical signs
Posterolateral thoracotomy scar: open lung biopsy
Shorter scar (3-4cm)
Reasons for pneumonectomy/lobectomy
Lung malignancy
Pulmonary metastasis
Localised bronchiectasis
Old TB
Fungal infections
Traumatic lung injury
Large emphysematous bullae
Congenital lung disease
Bronchial obstruction
Subtypes of pneumonectomy
Simple
- removal of affected lung
Extrapleural
- removal of affected lung plus part of the diaphragm, pleura, and pericardium on ipsilateral side
- linings then replaced with surgical Gortex
- mainly used in treatment of mesothelioma
Proportion of NSCLC suitable for surgery
25%
Mortality rates for pneumonectomy and lobectomy
Lobectomy 2-4%
Pneumonectomy 6%
Right side 10-12%
- higher rates of complications
Left side 1-3.5%
Post-pneumonectomy syndrome pathogenesis
Dyspnoea, cough, inspiratory stridor, pneumonia
Most common in right side pneumonectomy
6 months post surgery (can be years)
Extrinsic compression of distal trachea and main-stem bronchus due to mediastinal shift and compensatory hyperinflation of remaining lung
Management of post-pneumonectomy syndrome
Surgical repositioning of mediastinum and filling of post-pneumonectomy space
Using non-absorbable material and possible stenting of bronchi
Definition of cor pulmonale
Alteration in structure and function of the right ventricle and fluid retention due to pulmonary hypertension caused by disease affecting the lung and its vasculature
Gold standard investigation for pulmonary hypertension
Right heart catheterisation
Definition of pulmonary hypertension
Mean pulmonary artery pressure >25mmHg
Pulmonary capillary or left atrial pressure <15mmHg
Caused by increase in pulmonary blood flow, vascular resistance, or elevated pulmonary venous pressure
Common causes of cor pulmonale
COPD
Interstitial lung disease
Obstructive sleep apnoea
Hypoventilation disorders
Management of cor pulmonale
Optimise management of underlying condition
LTOT
Overnight NIV for hypoventilation syndromes
Diuretics
