Respiratory System Flashcards
What are the causes of an ipsilateral trachea on CXR?
- Pneumonectomy
- Lobar or total lung collapse
3.
Borders of the chest drain site? - triangle of safety (4)
- Anterior border of lat dorsi
- Lateral border of pectorals major
- Line superior to horizontal level of nipple
- Apex below axilla
What do these symptoms suggest an infection of?
- Flu-like symptoms with fever and dry cough
- Patient recently been on package holiday to Greece
- Deranged LFTs and hyponatraemia labs
Legionella pneumophila - Legionnaire’s disease
What is the treatment for Legionnaire’s disease?
Erythromycin
What is the most likely diagnosis for a young person with a dry cough and flu-like symptoms for one week, with tender red patches on shins?
Mycoplasma pneumoniae
What are the red, tender patches on shins from mycoplasma pneumoniae?
Erythema nodosum/multiforme
What will be seen on investigations (CXR/bloods) for someone with mycoplasma pneumoniae?
Bilateral consolidation on CXR
Thrombocytopenia and low Hb on bloods
What is the management of mycoplasma pneumoniae?
Erythromycin/clarithromycin
What are the three main atypical pneumonias?
- Mycoplasma pneumoniae
- Legionella pneumophilia
- Chlamydia pneumoniae
What are the most common causes of CAP? (3)
- Staph aureus
- Strep pneumoniae
- Legionella pneumophila
What are the three common causes of HAP? (3)
- Pseudomonas aeruginosa
- Klebsiella
- Haemophilus influenza
What is the CURB65 scores boundaries?
C - confusion AMTS <8 U - urea >7 R - RR >30 B - <90/60 65
What is the mnemonic helpful to learn acute life threatening asthma?
33, 92 CHEST PEFR<33% predicted O2 sats <92% C - cyanosis H - hypotension E - exhaustion S - silent chest T - tachycardia
What are the boundaries for acute severe asthma? (4)
- PEFR 33-50%
- Can’t complete sentences
- RR >25/min
- Pulse >110pm
What are the boundaries for moderate acute asthma? (4)
- Peak flow predicted 50-75%
- RR <25/min
- Pulse <110bpm
- Normal speech
When decided if someone needs long-term oxygen therapy, how many ABG measurements need to be taken and how many weeks apart?
2 measurements, at least 3 weeks apart, and not sooner than 4 weeks after an acute exacerbation of disease
When is long-term oxygen therapy considered for patients? (9) …good luck with those
- COPD with PaO2 <7.3kPa
- COPD with PaO2 7.3-8kPa with secondary polycythaemia, nocturnal hypoxaemia, peripheral oedema or evidence of pulmonary hypertension
- Severe chronic asthma PaO2<7.3kPa (or persistent disabling dyspnoea)
- Interstitial lung disease with PaO2<8
- Cystic fibrosis when PaO2<7.3 or the secondary problems described above
- Obstructive sleep apnoea despite continuous CPAP
- Pulmonary malignancy
- Heart failure with daytime PaO2<7.3kPa
- Paediatric respiratory disease
How is legionella pneumophila diagnosed?
Urinary antigen
What is the atypical infection associated with farm animals?
Coxiella burnetti
What is the atypical infection associated with exposure to birds?
Chlamydia psittaci
What are the characteristics associated with squamous cell cancer? (4)
- Typically central tumours
- Most present as obstructive lesions of the bronchus, leading to infection
- Local spread is common but widespread mets occur relatively late
- Squamous ell has the strongest association with smoking out of all the lung cancers
What is the lung cancer least associated with smoking? most common type affecting non-smokers?
adenocarcinoma
Where do adenocarcinomas most commonly metastasise to? (2)
Brain and bone
How can bronchiectasis present?
A chronic cough with production of think, yellow sputum, sometimes tinged with blood. Recurrent episodes of fever and pleuritic chest pain requiring antibiotics.
What is bronchiectasis?
A condition where there is permanent dilatation of the bronchi and bronchioles due to the destruction of elastic and muscular components of the bronchial wall. It is often a consequence of recurrent infections secondary to an underlying condition.
What are the causes of bronchiectasis?
- 50% idiopathic
- TB, pneumonias, flu
- Childhood infection e.g. measles, pertussis, RSV
- Immunodeficiency e.g. HIV
- Connective tissue disorders e.g. SLE, Marfan’s, systemic sclerosis, RA, sjogrens
- Congenital: CF, kartegener’s
What are the symptoms of bronchiectasis? (3)
- Chronic productive cough
- Large volume of purulent sputum
- Haemoptysis, SOB, chest pain
What investigations may be carried out for suspected bronchiectasis?
- CXR
- CT
- Sputum cultures
What is the treatment for bronchiectasis? (5)
- Lifestyle changes
- Chest physio
- Bronchodilators
- Short term antibiotics for exacerbations e.g. cipro/taz
- Long term antibiotics e.g. azithromycin
How can sarcoidosis present? (6)
- Breathlessness
- Cough
- Skin lesions around nose with indurated plaques and discolouration (lupus pernio)
- Painful red eyes with blurred vision and photophobia
- Low grade fever
- Arthralgia
What is the treatment for sarcoidosis? (3)
- Corticosteroids
- Cytotoxics
- Lung transplant
What would be the top differential for a middle aged male presenting with gradually progressive dyspnoea on exertion and a non-productive cough, with no history of underlying lung disease or other systemic symptoms like rash or arthralgia, with restrictive pattern on spirometry?
Idiopathic pulmonary fibrosis
What are the classic descriptions seen on CT for idiopathic pulmonary fibrosis?
Ground glass appearance that develops into honeycombing - interstitial thickening
What are the two types of pleural effusions that can occur/
They are fluids that collect between the parietal and visceral pleural surfaces of the thorax, and are either transudative or exudative.
What is the difference between transudative and exudative pleural effusions?
Exudative effusions are from local inflammatory sources, while transudative arise from more systemic factors.
Which have more protein, exudative or transduative?
Exudative
What is the Light’s criteria?
If the pleural fluid protein is between 25-30g/L, Light’s criteria is used to differentiate between exudate and transudate.
Using Light’s criteria how is exudative effusion defined?
- Pleural protein to serum protein ratio >0.5
- Pleural LDH to serum LDH ratio >0.6
- Pleural LDH greater than two-thirds of upper limit or normal for serum
What is the treatment for pleural effusions?
It depends on the cause…
- Malignancy = further imaging and therapeutic drainage
- Infective (empyema) = IV antibiotics, chest drain and supportive therapy
- Congestive heart failure = diuretic and supportive therapy
Which TB medication is most likely to cause optic neuritis?
Ethambutol
Which of the anti-TB drugs are only given for 2 months as opposed to 6?
- Pyrazinimide
2. Ethambutol
Which bacteria is the most likely cause of an infective exacerbation of COPD with no features evident on CXR?
Haemophilus influenzae
What are the pulmonary causes of acute respiratory distress syndrome (ARDS)? (3)
- Pneumonia
- Gastric aspiration
- Inhalation injury
What are the systemic causes of ARDS? (9)
- Shock/sepsis
- Haemorrhage
- Pancreatitis
- Acute liver failure
- Head injury
- Malaria
- Fat embolism
- Burns
- Drugs/toxins
What happens in ARDS?
There is release of inflammatory mediators which cause increased capillary permeability and non-cardiogenic pulmonary oedema (often accompanied by multi-organ failure)
What are the clinical features of ARDS? (5)
- Cyanosis
- Tachypnoea
- Tachycardia
- Peripheral vasodilatation
- Bilateral fine inspiratory crackles
What investigations are performed for ARDS?
- CXR
- FBC, U&Es, LFTs, amylases, clotting, CRP, blood cultures, ABG
- Pulmonary artery catheter to measure capillary wedge pressure
What is the management for someone with ARDS?
Normally requires CPAP for respiratory support, and then treat the underlying cause/support circulation with haemodynamic monitoring in ITU.
What is the mortality rate of ARDS?
50-75%
What are the symptoms of a PE? (4)
- Acute SOB
- Pleuritic chest pain
- Haemoptysis
- Dizziness/Syncope
What are the signs of a PE? (8)
- Pyrexia
- Cyanosis
- Tachypnoea
- Tachycardia
- Hypotension
- Raised JVP
- Pleural rub
- Pleural effusion
What is the management for a patient who is repeatedly getting PEs despite on adequate anticoagulation?
Placement of a vena cava filter
Which drug is indicated if the patient has a massive PE?
Thrombolysis - alteplase
Which HLA is sarcoidosis associated with?
HLA-DRB1
How does acute sarcoidosis commonly present?
Erythema nodosum +/-polyarthralgia
What is seen on CXRs of people with sarcoidosis?
Bilateral hilar lymphadenopathy +/- fibrosis
What symptoms of pulmonary disease will people with sarcoidosis present with? (4)
- Dry cough
- Progressive dyspnoea
- Reduced exercise tolerance
- Chest pain
What are the non-pulmonary signs of sarcoidosis? (10)
- Lymphadenopathy
- Hepatomegaly
- Splenomegaly
- Uveitis
- Conjunctivitis
- Sicca
- Glaucoma
- Erythema nodosum
- Lupus pernio
- Arrhythmias
Which bloods are often raised in someone with sarcoidosis? (4)
- Raised ESR
- Raised LFT
- Raised calcium
- Immunoglobulins
What would a tissue biopsy of someone with sarcoidosis show?
Non-caseating granulomata
In someone with sarcoidosis, what may be seen on X-ray of the hands?
Punched out lesions in terminal phalanges
What is the treatment for acute sarcoidosis?
NSAIDs, bed rest
When are corticosteroids (prednisolone 40mg) indicated for someone with sarcoidosis? (4)
If they have…
- Parenchymal lung disease
- Uveitis
- Hypercalcaemia
- Neurological/cardiac involvement
What is the prognosis for sarcoidosis?
60% of patients with thoracic sarcoidosis resolve over 2 years. 20% respond to steroid therapy and the rest don’t improve despite therapy.
What are the causes of bilateral hilar lymphadenopathy? (5)
- Sarcoidosis
- Infection e.g. TB
- Malignancy e.g. lymphoma, carcinoma
- Organic dust disease e.g. silicosis
- Extrinsic allergic alveolitis
What is the commonest cause of interstitial lung disease?
Idiopathic pulmonary fibrosis
What are the symptoms of idiopathic pulmonary fibrosis? (5)
- Dry cough
- Exertional dyspnoea
- Malaise
- Weight loss
- Arthralgia
What are the signs associated with idiopathic pulmonary fibrosis? (3)
- Cyanosis
- Finger clubbing
- Fine end-inspiratory crepitations
What are the complications of idiopathic pulmonary fibrosis? (2)
- Respiratory failure
2. Increased risk of lung cancer
Which antibody blood test is positive in 30% of patients with idiopathic pulmonary fibrosis?
ANA
On CXR, what is seen in someone with idiopathic pulmonary fibrosis?
- Decreased lung volume
- Bilateral lower zone reticulonodular shadows
- Honeycomb lung
What is the management for idiopathic pulmonary fibrosis? (3)
- Oxygen
- Pulmonary rehabilitation
- Opiates
- it is strongly recommended that steroids are NOT used unless the diagnosis is in doubt
What is the prognosis for someone with idiopathic pulmonary fibrosis?
50% 5 year survival rate
What is obstructive sleep apnoea syndrome?
This disorder is characterised by intermittent closure/collapse of the pharyngeal airway, causing apnoeic episodes during sleep. These are terminated by partial arousal.
What are the features of obstructive sleep apnoea syndrome? (6)
- Loud snoring
- Daytime somnolence
- Poor sleep quality
- Morning headache
- Decreased libido
- Decreased cognitive performance
What are the complications of obstructive sleep apnoea syndrome?
- Pulmonary hypertension
2. Type II respiratory failure
What constitutes significant sleep apnoea?
15 or more episodes of apnoea or hypopnea during 1 hour of sleep
What is the management for obstructive sleep apnoea? (4)
- Weight loss
- Avoidance of tobacco and alcohol
- CPAP via a nasal mask - recommended by NICE for those with moderate to severe disease
- Surgery to relieve pharyngeal obstruction is occasionally needed
What is cor pulmonale?
Right heart failure caused by chronic pulmonary arterial hypertension
What are the causes of cor pulmonale? (3 categories, lots of causes)
- Chronic lung disease (COPD, bronchiectasis, pulmonary fibrosis, chronic asthma, lung resection)
- Pulmonary vascular disorders (emboli, vasculitis, ARDS, sickle-cell disease)
- Neuromuscular/skeletal diseases (myasthenia gravis, poliomyelitis, motor neurone disease, scoliosis, kyphosis)
What are the complications of pneumonia? (9)
- Respiratory failure
- Hypotension
- Atrial fibrillation
- Pleural effusion
- Empyema
- Lung abscess
- Sepsis
- Pericarditis/myocarditis
- Jaundice
What is bronchiectasis?
Chronic infection of the bronchi and bronchioles leading to permanent dilatation of these airways. The main causes are: H. influenzae Step. pneumoniae Staph. aureus Pseudomonas. aeruginosa
What are the signs and symptoms of bronchiectasis? (6)
- Persistent cough
- Copious purulent sputum
- Intermittent haemoptysis
- Finger clubbing
- Coarse inspiratory crepitations
- Wheeze
What is the management for type II respiratory failure?
- Treat the underlying cause
- Controlled oxygen therapy - start at 24% O2
- Recheck ABG after 20 minutes – if CO2 decreasing continue O2 and consider increasing concentration, however if CO2 still high and hypoxic, then consider NIV.
Why do transudative pleural effusions occur? causes? (5)
Normally due to increased venous pressure –> cardiac failure, constrictive pericarditis, fluid overload. Other causes include Meig’s syndrome and hypothyroidism.
Why do exudative pleural effusions occur? causes? (3)
Normally due to increased leakiness of pleural capillaries secondary to infection, inflammation or malignancy
What are the signs of pleural effusion? (3)
- Decreased expansion
- Stony dull percussion
- Diminished breath sounds
What is a lung abscess?
A severe, localised suppurative infection in the substance of the lung, associated with necrotic cavity formation
If multiple small abscess formations occur in the lungs what can this sometimes be known as?
Necrotising pneumonia
What is the most common cause of lung abscesses?
The most frequent cause is aspiration of anaerobic organisms from the mouth in those predisposed to aspiration pneumonia with immunodeficiency and cough reflex. A pneumonitis develops which progresses to abscess formation over a period of days or weeks
What are the precipitating mechanisms for lung abscess formation?
- Inhalation of a foreign body
- Bacteraemia seeding in the lungs
- Tricuspid endocarditis –> septic pulmonary embolus
- Extension of hepatic abscess
- Association with lung cancer
- Penetrating pulmonary trauma
What are two classifications of lung abscesses?
Primary and secondary
What is primary lung abscess?
Occurs in previously normal lungs and may follow aspiration
What is a secondary lung abscess?
Occurs in patients with an underlying lung abnormality
What organisms are known to cause lung abscess most commonly? (6)
- Staph aureus
- Klebsiella pneumoniae
- Anaerobes
- TB
- Fungal - aspergillus
- Parasites
What are the risk factors for developing a lung abscess? (8)
- Alcoholism/drug misuse
- Following general anaesthesia
- Diabetes mellitus
- Severe periodontal disease
- Stroke/cerebral palsy/cognitive impairment –> increased risk of aspiration
- Immunosuppression
- Congenital heart disease
- Chronic lung disease - cystic fibrosis
How does a lung abscess present? (5)
- Onset of symptoms is often insidious (though more acute in following pneumonia)
- Spiking temperature with rigors and night sweats
- Cough +/- phlegm production
- Pleuritic chest pain
- Breathlessness
What type of phlegm is commonly produced in someone with a lung abscess?
Frequently foul tasting, foul smelling and often blood-stained
What are the signs of a lung abscess? (8)
- Tachypnoea
- Tachycardia
- Finger clubbing in chronic cases
- Dehydration
- High temperature
- Localised dullness to percussion (if consolidation is also present or effusion)
- Bronchial breathing and/or crepitations
- Look for signs of severe periodontal disease and infective endocarditis
What are the differential diagnosis for lung abscess? (6)
- Other causes of chest infection e.g. pneumonia or TB (without abscess)
- Neoplasisa
- Pulmonary embolism
- Vascilutis (WEGENER)
- Sarcoidosis with cavities
- Infected bronchogenic cyst
What investigations should be done for someone with suspected lung abscess? (7)
- Bloods - FBC (anaemia/neutrophilia), U&Es (renal function), LFTs, CRP/ESR
- Blood cultures
- Sputum cultures
- CXR
- Tapping or draining of fluid or empyema with microbiology/cytology samples
- Fibre-optic bronchoscopy
- Trans-thoracic biopsy/aspiration
What is the management of lung abscess? (4)
- Analgesia
- Oxygen if required
- Rehydration if required
- Postural drainage with chest physiotherapy
- Antibiotics (80-90% successfully treated with these)
Which antibiotics are recommended to treat lung abscess?
First-line therapy includes:
Beta-lactam inhibitor or cephalosporins (3rd generation)
+
Clindamycin
What is the management option if the antibiotics don’t work to treat the lung abscess?
Surgery - drainage via a bronchoscope, CT-guided percutaneous drainage or cardiothoracic surgical intervention
What are the associated complications with surgery for lung abscess drainage?
- Empyema
2. Broncoalveolar air leak (especially in children)
What is cyanosis?
An abnormal blue discolouration of the skin and mucous membranes, caused by an increase in the deoxygenated haemoglobin level to above 5g/dl.
In patients with what common would cyanosis occur at lower levels of oxygen saturation compared to standard level?
People with anaemia
Cyanosis can be divided into central and peripheral. What are the features? of central cyanosis? (causes, signs) (7)
Caused by diseases of the heart, lungs or abnormal haemoglobin. 1. Pulmonary oedema 2. Pulmonary embolism 3. COPD 4. Acute severe asthma 5. ARDS 6. Eisgenmenger's syndrome 7. Polycythaemia rubra vera Cyanosis is seen in the tongue and lips and is due to desaturation of the central arterial blood - often associated with shunting of deoxygenated venous blood into the systemic circulation.
What symptoms/signs may be associated with central cyanosis?
Depends on cause, but possibly…
- Dyspnoea
- Tachypnoea
What causes peripheral cyanosis? (4)
Decreased local circulation and increased extraction of oxygen in the peripheral tissues. Isolated peripheral cyanosis occurs in conditions associated with peripheral vasoconstriction and stasis of blood in the extremities, leading to increased peripheral oxygen extraction:
- Congestive heart failure
- Circulatory shock
- Exposure to cold temperatures
- Abnormalities of the peripheral circulation (Raynaud’s phenomenon, peripheral arterial disease)
What are the cardiac causes of cyanosis in neonates? (5)
- Transposition of the great arteries
- Fallot’s tetralogy
- Stenosis or atresia of the pulmonary valve or tricuspid valve
- Truncus arteriosus
- Persistent fetal circulaiton - patent ductus arteriosus and foramen ovale
What are the respiratory causes of central cyanosis in neonates?
- Respiratory distress syndrome
- Birth asphyxia
- Pneumothorax
- Meconium aspiration
- Pulmonary oedema
If someone with central cyanosis is on high flow oxygen, yet their sats do not increase above 95%, what does this suggest is happening?
There is likely to be pulmonary intravascular shunting of blood bypassing the alveoli
What is haemoptysis?
Coughing of blood originating from the respiratory tract below the level of the larynx.
What should haemoptysis be differentiated from?
- Haematemesis (vomiting of blood from the GI tract)
- Pseudohaemoptysis (where a cough reflex is stimulated by blood not derived from the lungs or bronchial tubes. This may be from the oral cavity or nasopharynx e.g. following epistaxis) or following aspiration of haematemesis into the lungs)
What are the causes of haemoptysis? (10)
- Malignancy
- Bronchitis/bronchiectasis
- Foreign body
- Airway trauma
- Lung abscess
- Pneumonia (bacterial or viral)
- TB
- Goodpasture’s syndrome
- Wegener’s granulomatosis
- Behcet disease
What is Behcet disease characterised by? (6)
- Recurrent oral ulcers
- Recurrent genital ulceration
- Eye lesions - anterior uveitis
- Skin lesions - erythema nodosum
- Pathergy (exaggerated skin injury occurring after a minor trauma)
+
non specific symptoms e.g. fatigue, muscle pains, transient fevers, headaches
What are the differentials for Behcet disease? (4)
- Sarcoidosis
- MS
- Crohn’s disease
- Takayasu’s arteritis
