Resp conditions basics Flashcards
COPD epidemiology
Common in smokers, rarely symptomatic before middle age.
COPD signs and symptoms
Cough with production of sputum, wheeze and breathlessness.
Often lean forward, barrel chested, prolongued expiration.
May have secondary pulmonary hypertension, raised JVP and oedema.
Cachexia can occur.
COPD investigations
Spirometry
FEV1 reduced more than FVC
Diagnosis for COPD
FEV1 less than 80% predicted (unless mild)
FEV1:FVC less than 0.7 (all COPD sufferers)
Little or no reversibility.
COPD pathology
Chronic bronchitis is inflammation
Emphysema is enlargement of air spaces accompanied by destruction of their walls.
Single greatest factor is cigarette smoking.
How does cigarette smoking cause COPD
Irritant causing hypertrophy of submucosal glands and hypersecretion of mucus in large airways, and respiratory bronchiolitis in small airways.
Alters oxidant/anti-oxidant balance and protease/antiprotease balance (due to increased inflammation) leading to emphysema.
Low α1-antitrypsin leads to emphysema with/w’out smoking.
Complications of COPD
Cor pulmonale
Respiratory failure.
Treatment of COPD
Smoking cessation Bronchodilators (B2-agonists and antimuscarinic ipratropium bromide) Corticosteroids sometimes Vaccination to prevent IECOPD. Oxygen.
Treatment of IECOPD
Oxygen
Bronchodilators
Antibiotics
BiPAP (Bilevel positive airway pressure)
Bronchiectasis epidemiology
In developed countries most common cause is cystic fibrosis, but can be caused by infections.
Bronchiectasis clinical picture
Cough and sputum production; if severe, latter is green and foul-smelling.
Possible massive haemoptysis, breathlessness and wheeze
Bronchiectasis OE
clubbing and coarse inspiratory crackles.
Bronchiectasis investigations.
Chest X-ray can be normal or dilated bronchi with thickened walls, and multiple fluid containing cysts.
CT may show airway dilatation, bronchial wall thickening and cysts.
In infective exacerbration do sputum culture.
Spirometry often shows obstructive pattern.
Bronchiectasis treatment
Physiotherapy for postural drainage
Antibiotics
Bronchodilators if airway limitation
Steroids to decrease progression
Cystic fibrosis definition
An autosomal recessive condition caused by mutations in CFTR gene resulting in a defective chloride channel in epithelial cell membranes and hence an increase in viscosity and tenacity of mucus on epithelial surfaces in the pancreas, respiratory, GI and reproductive tracts.
Cystic fibrosis epidemiology
1:2000 live births.
Cystic fibrosis clinical picture.
Normal at birth, respiratory symptoms normally present.
Bronchiectasis and obstructive disease are primary causes of morbidity and mortality.
Meconium ileus in 1/5 of CF newborns: pathognomic.
Causes of infections in cystic fibrosis
Gram -ives, Staph aureus and H. influenzae in infants.
Pseudomonas in adult.
Cystic fibrosis treatment
Management of bronchiectasis and exocrine pancreatic insufficiency
Cystic fibrosis investigation
Family history
High sweat sodium and chloride (more than 60 mmol/l)
Blood DNA analysis of gene defect
Absent vas deferens and epididymis.
Asthma definition
A common chronic inflammatory condition characterised by reversible airflow limitation, airway hypersensitivity and inflammation of the bronchi.
Asthma epi
Common, especially in teenage
Asthma pathogenesis
Narrowing of airway is due to smooth muscle contraction, thickening of for airway wall and increased secretion within the lumen.
Asthma clinical features
Wheezing, cough, chest tightness and shortness of breath; intermittent, worse at night.
Asthma treatment
B-agonists Antimuscarinic bronchodilators Corticosteroids Anti-inflammatory agents such as sodium cromoglicate (in mild) leukotriene receptor antagonists.
Emergency treatment of acute severe asthma
O2
Salbutamol or terbutaline by oxygen driven nebs
Hydrocortisone 100 mg IV or 60mg oral
NO SEDATIVES
Abx
CXR to exclude pneumothorax or pneumonia.
Definition of pneumonia
An inflammation of lung tissue usually caused by infection. It is defined both anatomically and by aetiology.
Clinical features of pneumonia
How to assess severity.
Very variable: pyrexia, cough, sputum, pleurisy and dyspnoea.
Consolidation, pleural rub, pleural effusion.
Assess severity using CURB 65
Pneumonia investigations
CXR for outpatients
For inpatients: bloods (WBC, liver biochem, U&Es, serology), ABGs, CXR,
Pneumonia treatment
Mild CAP: oral amoxicillin or clarithromycin.
Severe CAP: both above
CURB-65 > 3: IV cefuroxime and clarithromycin
Fluids.
Pneumonia complications
Pleural effusion,
Respiratory failure
Lung abscess
Empyema.
Lung abscess definition
Localised suppuration of the lung associated with cavity formation.
Lung abscess clinical features
Worsening pneumonia
Copious amounts of foul smell sputum.
Lung abscess investigations
Bacteriological investigation on aspiration or bronchoscopy samples.
TB clinical features
Malaise, anorexia, weightloss, fever and cough
Mucoid, purulent or blood stained sputum
TB investigations
CXR (patchy shadows in upper zones) Ziehl-Neelsen stain for acid fast bacilli (sputum) PCR testing (not entirely reliable)
In miliary TB: lumbar puncture and CSF examination.
HIV testing.
TB management
6 months: rifampicin and isoniazid.
2 months at start: pyrazinamide and ethambutol
Sarcoidosis def
A multisystem granulomatous disorder of unknown aetiology.
Sarcoidosis epi
All ethnicities, but rare in Japanese and severe in African blacks. Peak incidence in 30s. More women than men.
Sarcoidosis clinical features
Bilateral hilar lymphadenopathy
Erythema nodosum
Uveitis
Polyarthralgia
Sarcoidosis complications
Progressive fibrosis of lungs leading to increased effort, cor pulmonale and death.
Blindness.
Sarcoidosis investigations
CXR
Transbronchial biopsy
Lung function tests show restrictive lung defect
ACE is raised in 75% of patients (not diagnostic)
Sarcoidosis differential diagnoses
Lymphoma, TB, Bronchial carcinoma w secondary spread.
Sarcoidosis management
Steroid use contested.
Topical steroids used for eye involvement.
Wegener’s granulomatosis def
This is a vasculitis of unknown aetiology characterised by lesions involving the upper resp tract, the lungs and the kidneys.
Wegener’s granulomatosis clinical picture
Often starts with rhinorrhea, progresses to nasal mucosal ulceratoin, cough, haemoptysis and pleuritic pain.
Wegener’s granulomatosis investigations
ANCA in 90% of active cases.
CXR (nodular masses, pneumonic infiltrates with cavitation)
Wegener’s granulomatosis treatment
Cyclophosphamide
Idiopathic pulmonary fibrosis epi
rare
Idiopathic pulmonary fibrosis def
Rare disorder of unknown aetiology characterised by sequential acute lung injury resulting in scarring, which generally presents in middle age.
Idiopathic pulmonary fibrosis presenting clinical features
Exertional dyspnoea and non-productive cough.
Idiopathic pulmonary fibrosis end-stage clinical features
Respiratory failure, pulmonary hypertension and cor pulmonale.
Idiopathic pulmonary fibrosis investigations
Blood gases (hypoxaemia w normal PaCO2) CXR (ground glass, honeycombing) CT (irreg linear opacities and honeycombing) Resp fuction tests (restrictive defect) Histology biopsy (Autoantibodies in 1/3)
Idiopathic pulmonary fibrosis treatment
Oxygen, pulmonary rehab, opiates and palliative. No high dose steroids unless diagnosis in doubt.
Lung transplantation.
Extrinsic allergic alveolitis def
A disease of widespread diffuse inflammation in the alveoli and small airways of the lung in response to an inhaled antigen.
Type 1 resp failure definition
PaO2 less than 8, PaCO2 less than 6
Type 2 resp failure definition
PaO2 less than 8, PaCO2 more than 6.
Type 1 resp failure definition
PaO2 less than 8, PaCO2 less than 6
Type 2 resp failure definition
PaO2 less than 8, PaCO2 more than 6.
Normal PaO2
10.5-13.5 kPa
Spirometry results showing restrictive defect
FVC decreased and FEV1/FVC ratio is normal or raised
Causes of restrictive defect
Sarcoidosis, Pneumoconiosis, interstitial pneumonias, connective tissue diseases, pleural effusion, obesity, kyphoscoliosis, neuromuscular problems.
Common organisms causing CAP
Strep pneumoniae
Haemophilus influenzae
Mycoplasma pneumoniae.
Common organisms causing HAP
Staph aureus, pseudomonas, klebsiella, bacterioides and etc.
Describe CURB-65 score
Confusion. Abbreviated mental test score less than 8.
Urea of more than 7 mmol/L
Resp rate of more than 30 breaths per minute
BP of less than 90 systolic.
Age above 65.
One point for each of the above:
Pneumococcal pneumonia (basic and treatment)
Commonest bacterial pneumonia. Treat with amoxicillin, benzylpenicillin or cephalosporin.
Staphylococcal pneumonia
Bilateral cavitating bronchopneumonia
Who gets Pseudomonas pneumonia?
People with bronchiectasis or CF. Also those in ITU or after surgery.
Symptoms for mycoplasma pneumonia?
Headaches, myalgia, arthralgia.
Dry cough.
Complications of mycoplasma pneumonia.
Skin rash (erythema multiforme), SJS, meningococcal encephalitis, Guillan-Barre syndrome.
Legionella pneumonia symptoms
Fever, malaise, myalgia,
Dry cough, dyspnoea
Extrapulmonary features of legionella infection
Anorexia, D&V, hepatitis, renal failure, confusion and coma.
Blood tests in legionella infection
Lymphopenia, hyponatraemia, and deranged LFTs.
What are Light’s criteria to diagnose exudative pleural fluid?
Pleural fluid is an exudate if one or more of the following
criteria are met:
Pleural fluid protein divided by serum protein is >0.5
Pleural fluid lactate dehydrogenase (LDH) divided by
serum LDH is >0.6
Pleural fluid LDH >2/3 the upper limits of laboratory
normal value for serum LDH.
Congenital diseases causing bronchiectasis
CF, Young’s syndrome, primary ciliary dyskinesia, Kartagener’s syndrome.
Infections causing bronchiectasis
Measles, pertusis, bronchiolitis, pneumonia, TB, HIV
Non-congenital, non-infective causes of bronchiectasis
Obstruction, allergic bronchopulmonary aspergillosis, hypogammaglobulinaemia, rheumatoid arthritis, ulcerative colitis, idiopathic.
5 ways aspergillus can affect the lung
Asthma in response to spores Allergic bronchopulmonary aspergillosis Aspergilloma Invasive aspergillosis Extrinsic allergic alveolitis
Allergic bronchopulmonary aspergillosis
Type I and III hypersensitivity reactions to aspergillus fumigatus. Occurs in 1-5% of asthmatics, 2-25% of CF.
Initially constriction, then bronchiectasis.
Risk factors for invasive aspergillosis
Immunocompromise (HIV, leukaemia, burns, Wegener’s and SLE)
Broad-spectrum antibiotic use.
COPD pink puffers tend to progress to…
Type 1 respiratory failure
COPD blue bloaters tend to progress to…
Cor pulmonale.
Causes of type 1 resp failure
Pneumonia, pulmonary oedema, PE, asthma, emphysema, pulmonary fibrosis, ARDS.
Causes of type 2 resp failure
Pulmonary disease such as asthma, COPD, pneumonia, fibrosis,
Reduced respiratory drive due to sedative drugs, CNS tumour or trauma.
Neuromuscular disease
Thoracic wall disease (flail chest, kyphoscoliosis)
Neuromuscular diseases causing type 2 resp failure
Cervical cord lesion, diaphragmatic paralysis, poliomyelitis,, myasthenia gravis, Guillain-Barre syndrome
When to consider an ABG
Any sudden deterioration in an ill patient
Any acute exacerbation of resp condition
Any impaired consciousness or impaired resp effort.
Any signs of CO2 retention
Cyanosis, confusion, visual hallucinations.
Causes of transudative pleural effusions
Increased venous pressure or hypoproteinaemia.
Also hypothyroidism and Meigs’ syndrome.
Increased venous pressure: causes of transudative pleural effusion
cardiac failure, constrictive pericarditis, fluid overload.
Hypoproteinaemia: causes of transudative pleural effusion
cirrhosis, nephrotic syndrome, malabsorption
Causes of exudative pleural effusion
infection, inflammation or malignancy.
Extrinsic allergic alveolitis - causes
Proteins in bird droppings,
Farmer’s and mushroom worker’s lung
Malt worker’s lung
Sugar worker’s lung
Extrinsic allergic alveolitis - clinical features
4-6 h after exposure: fever, rigors, myalgia, dry cough, dyspnoea and crackles (no wheeze)
Chronically: dyspnoea, weight loss, type 1 resp failure.
Obstructive sleep apnoea
Intermittent closure of pharyngeal airway causing apnoeic episodes during sleep.
Obstructive sleep apnoea classical presentation
Obese middle-aged man presenting due to snoring and/or daytime somnolence, with partner describing apnoeic episodes during sleep.
Probable pathogen in 6-month-old who is ‘chesty’, has rhinitis and is off her feeds. Auscultation of her chest reveals bibasal crackles and an expiratory wheeze.
Respiratory syncytial virus
Disease caused by Mycoplasma pneumoniae
Atypical pneumonia
Flu-like symptoms classically precede a dry cough. Complications include haemolytic anaemia and erythema multiforme
Disease caused by Legionella pneumophilia
Atypical pneumonia
Classically spread by air-conditioning systems, causes dry cough. Lymphopenia, deranged liver function tests and hyponatraemia may be seen
Disease caused by Pneumocystis jiroveci
Common cause of pneumonia in HIV patients. Typically patients have few chest signs and develop exertional dyspnoea
Disease caused by Haemophilus influenzae
Community-acquired pneumonia
Most common cause of bronchiectasis exacerbations
Acute epiglottitis
