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Respiratory 

Respiratory
Chapter:
Respiratory
Author(s):

Tanya M. Monaghan

and James D. Thomas

DOI:
10.1093/med/9780198830849.003.0002
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date: 27 October 2021

18 COPD

Examination Findings

Inspection

  • Inhalers or nebulizers.

  • Sputum pot.

  • Tar-stained fingers.

  • Thin skin and bruising (disease and steroid use).

  • Proximal muscle wasting.

  • Use of accessory muscles of breathing.

  • Tachypnoea.

  • Prolonged expiratory phase.

  • Hyperinflation (‘barrel chest’).

Auscultation

  • Quiet breath sounds.

  • Polyphonic wheeze.

  • Heart sounds often quiet.

  • Heart rate may be irregular:

    • AF or multifocal atrial tachycardia.

The Essentials

  • COPD is characterized by airflow limitation which is associated with exposure to noxious inhaled material, predominantly cigarette smoke.

  • Features include:

    • Not fully reversible.

    • Progressive.

    • Characterized by exacerbations.

    • Associated with an inflammatory response that has adverse effects on other organs.

The Extras

Complications

Look for additional signs suggesting:

  • Cor pulmonale.

  • Lung cancer (these patients are usually smokers >60 years).

  • Ischaemic heart disease (greatly increased risk of cardiac morbidity and mortality).

BODE Index

  • Document independent predictors of mortality:

    • BMI (high risk if <19).

    • Obstruction (FEV1 as a percentage of predicted).

    • Dyspnoea (e.g. by MRC score).

    • Exercise capacity (e.g. by 6-minute walk test).

Showing Off

α‎-1 antitrypsin deficiency

  • α‎-1 antitrypsin deficiency is a recessively inherited problem with a carrier frequency of 1 in 10.

  • Impaired secretion of the glycoprotein α‎1AT which normally protects against tissue damage from enzymes such as neutrophil elastase.

  • Patients who smoke have wheeze in their 20s, bronchiectasis in their 30s, and limiting lower lobe emphysema by their 40s.

  • α‎1AT deficiency also causes impaired liver function in some patient and may lead to cirrhosis and liver failure.

19 Interstitial Lung Disease

The following describes idiopathic pulmonary fibrosis.

Examination Findings

Inspection

  • Signs of respiratory distress?:

    • Tachypnoea, cyanosis.

  • Digital clubbing:

    • Seen in 50% of patients with idiopathic pulmonary fibrosis. Its presence may be helpful but its absence is non-diagnostic.

  • Signs of thoracic deformity (e.g. kyphosis, scoliosis).

  • Signs of pulmonary hypertension or underlying connective tissue disease.

Palpation

  • Reduced chest expansion.

Percussion

  • Percussion note is not usually altered unless secondary pathology such as pneumothorax or collapse.

Auscultation

  • Fine mid- to late-inspiratory crackles (like ‘Velcro’) heard in the bases or mid zones is characteristic:

    • Signs may be localized to affected lobes.

    • Expiratory wheeze is less common but can occur in types of ILD.

  • Reduced air entry may be noted.

Signs of decompensation

  • Cyanosis.

  • Pulmonary hypertension.

    • Giant ‘V’ waves in the JVP, parasternal heave, loud pulmonary component of the second heart sound.

  • Right heart failure.

    • Raised JVP, peripheral oedema, pulsatile hepatomegaly, ascites.

The Essentials

Signs of underlying connective tissue disease

  • Sarcoidosis: lymphadenopathy, salivary gland enlargement, erythema nodosum, lupus pernio, hepatosplenomegaly, uveitis, neurological signs.

  • Systemic sclerosis: sclerodactyly, microstoma, ‘beak’-shaped nose, telangiectasia, calcinosis, arthropathy, myopathy, Raynaud’s syndrome.

  • Rheumatoid arthritis: rheumatoid nodules, ulnar deviation, MCP joint swelling, swan neck and boutonnière deformities.

  • Systemic lupus erythematosus: ‘butterfly’ malar rash, oral ulcers, alopecia, arthritis, pleural effusion, neurology.

  • Dermato-/polymyositis: muscle weakness, characteristic rash.

Differential diagnosis

  • Any pathology that can produce bibasal crackles on auscultation with or without clubbing (e.g. bronchiectasis, infection, COPD).

  • If the signs are mainly in the lung apices then consider:

    • Old TB.

    • Previous infection (especially fungal).

    • Ankylosing spondylitis (look for the ‘question mark’ posture and reduced anteroposterior movement of the chest wall in respiration).

    • Previous radiotherapy (look for burns, scars, and marker tattoos).

    • Sarcoidosis.

The Extras

Complications of treatment

  • Steroids: interscapular fat pad (‘buffalo hump’), rounded ‘moon-shaped’ facies, thin skin, bruising, proximal muscle wasting, cataracts, kyphosis or scoliosis secondary to osteoporotic fractures.

  • Azathioprine: bruising due to thrombocytopenia, jaundice if hepatotoxic.

  • Cyclophosphamide: hair loss, easy bruising (bone marrow suppression).

  • ▶ Always look for signs of active infection in anyone taking regular immunosuppressant therapy.

20 Lobectomy

Examination Findings

Inspection

  • May have chest wall deformity with flattening on the side of the surgery (ribs pulled in over site of surgery).

  • Reduced chest expansion on the side of the lobectomy.

  • Thoracotomy scar:

    • VATS lobectomy is a minimally invasive procedure that may only leave three small scars of port insertion.

  • A scar from insertion of a chest drain post lobectomy may be evident.

Palpation

  • Tracheal displacement towards the side of the surgery.

  • Displacement of the cardiac apex towards the side of the surgery.

  • Reduced expansion on the side of the surgery.

Percussion

  • Hyper-resonance on the side of the lobectomy:

    • Remaining lung expands to fill the thoracic cavity.

  • Dull percussion note in a previously resonant area as upward diaphragmatic displacement fills an area of the thoracic cavity previously occupied by lung parenchyma.

Auscultation

  • Reduced air entry over the area of the lobectomy.

The Essentials

Potential indications for lobectomy

  • Lung cancer.

  • Bronchiectasis.

  • Chronic lung abscess.

  • TB.

  • Benign tumours.

  • Fungal infections (e.g. life-threatening haemoptysis due to Aspergillus infection).

  • Congenital abnormalities.

Signs suggestive of the indication

  • Finger clubbing may suggest bronchiectasis or lung cancer (it does not resolve following lobectomy for neoplasia).

  • Peripheral calcified lymph nodes may suggest old TB.

Differential diagnosis

The main differential will be between a lobectomy and pneumonectomy. Signs are more localized with lobectomy, and tracheal and cardiac apex displacement less common. In addition, because the lung fills with fluid after a pneumonectomy, percussion note may be stony dull or dull, when it should be normal following a lobectomy operation.

The Extras

Other causes of thoracotomy scars

  • Oesophageal surgery.

  • Heart valve replacement.

  • Diaphragmatic repair.

  • Thoracic aortic aneurysm repair.

  • Anterior spinal tumour excision.

  • Latissimus dorsi flaps.

Showing Off

  • VATS is increasingly used for the diagnosis and treatment of lung and pleural disease:

    • A camera and other instruments are inserted via ports to enable a variety of procedures including lung and pleural biopsy, pleurodesis, decortications for empyema, wedge lung resection, and lobectomy.

    • The main advantage of VATS for patients is the lower occurrence of postoperative pain and shorter length of hospital stay.

21 Pleural Effusion

Examination Findings

Inspection

  • Reduced chest expansion unilaterally (if large).

Palpation

  • Trachea may be pushed away from the effusion.

  • Apex beat:

    • A large right effusion will displace the cardiac apex to the left.

    • A large left effusion may make the apex beat difficult to palpate.

Percussion

  • Percussion note is stony dull.

Auscultation

  • Markedly reduced breath sounds.

  • Reduced vocal resonance.

  • Collapsed or consolidated lung above the effusion may produce an overlying region of bronchial breathing.

  • ▶ Signs are anterior and posterior and do not conform to usual surface markings of lobar boundaries.

The Essentials

Possible causes can be split into those giving exudative or transudative effusions:

Exudates (increased capillary permeability)

  • Infection (bacterial pneumonia, mycobacterial).

  • Malignancy (commonest cause in over 60s).

  • Pulmonary embolism.

  • Autoimmune multisystem disorders (commonly rheumatoid or lupus).

  • Pancreatitis (may be haemorrhagic).

  • Drugs (check at http://www.pneumotox.com).

  • Post CABG (occurs in almost all cases).

Transudates (increased hydrostatic or reduced oncotic pressure)

  • Cardiac failure (commonest cause overall, usually bilateral).

  • Cirrhotic liver disease.

  • Peritoneal dialysis.

  • Nephrotic syndrome.

  • Hypothyroidism.

The Extras

Unless gross cardiac failure is present, a diagnostic tap should be performed and sent for:

  • Microscopy and culture.

  • Cytology (diagnoses >2/3 of malignant effusions).

  • pH (unless purulent):

    • <7.2 indicates the need for a chest drain in a parapneumonic effusion.

    • Lower pH in malignancy indicates pleurodesis is more likely to fail.

Showing Off

  • A cause of pleural effusion not to be missed is that of oesophageal rupture or ‘Boerhaave’s syndrome’. This is life-threatening and usually occurs after gastroscopy, however >10% occur after vigorous vomiting:

    • Named after the eighteenth-century Dutch physician that described the death of an Admiral after regurgitating a gluttonous feast.

22 Pneumothorax

Examination Findings

Inspection

  • Is the patient relatively high risk:

    • Young, tall, and thin?

    • Older with COPD?

    • Subject to recent trauma, biopsy, or central line?

  • Tachypnoea.

Palpation

  • Tachycardia.

  • Reduced vocal resonance on affected side.

Percussion

  • Increased percussion note if pneumothorax is very large.

Auscultation

  • Reduced breath sounds on affected side.

Tension pneumothorax

  • Cyanosis.

  • Hypotension.

  • Trachea and apex pushed away from affected side.

The Essentials

  • Primary spontaneous pneumothorax usually results from the rupture of a subpleural bleb after coughing or straining:

    • These blebs are commoner if tall and lean, and more so in smokers (×10 increased risk), especially if smoking drugs other than tobacco.

  • A relatively small secondary pneumothorax (i.e. one in the presence of underlying lung disease or after trauma or procedure) may produce marked symptoms and compromise in the absence of classical chest signs, e.g. in CF.

  • ▶ A suspected tension pneumothorax is a medical emergency and must be decompressed by the placement of a large-bore cannula in the second intercostal space in the midaxillary line without waiting for a chest radiograph.

The Extras

  • Around half of patients with spontaneous pneumothorax will present >48 hours after symptom onset.

  • Around half of patients with a pneumothorax will have a recurrence.

Management

  • Primary pneumothoraces require initial needle aspiration unless small (<2 cm rim on chest radiograph) and relatively asymptomatic.

  • An intercostal drain is placed in the first instance for a secondary pneumothorax, though there is no evidence that large tubes (>20 F) are more likely to lead to improvement.

  • After discharge, patients must avoid pressure changes such as air travel (risk diminishes with time), and diving (must never SCUBA dive).

Showing Off

  • A 2 cm rim of pneumothorax on chest radiograph still equates to around 50% of the volume of the hemithorax.

  • Some mutations in the fibrillin-1 gene cause classical Marfan’s syndrome (see 100: Marfan’s Syndrome), but others produce more mild phenotypes with no aortic root dilatation but an increased risk of pneumothorax.

23 Previous Tuberculosis

Examination Findings

Old TB can present clinically in a variety of ways depending on where the infection was localized to and what treatments were used.

As upper lobe fibrosis

  • Reduced air entry apically.

  • Apical crepitations/bronchial breathing.

  • Deviated trachea towards the affected side.

  • Reduced expansion on affected side.

  • Dull percussion note on affected side.

  • The apex beat may be displaced towards the affected side.

With evidence of a phrenic nerve crush

  • Supraclavicular scar of procedure.

  • Evidence of raised hemidiaphragm ipsilaterally.

  • Dull percussion note.

  • Reduced or absent breath sounds at the lung base.

  • Reduced chest wall expansion.

With evidence of previous thoracoplasty

  • Obvious chest wall deformity with flattening of the chest wall on the side of the procedure.

  • Palpable absence of ribs on the side of the deformity.

With evidence of previous lobectomy

  • Thoracotomy scar with evidence of lobectomy clinically (see 20: Lobectomy).

With evidence of longstanding pleural thickening (from TB effusion/empyema)

  • Reduced (but not absent) breath sounds over the area of pleural thickening.

  • Reduced chest wall expansion.

  • Dullness to percussion.

The Essentials

Extrapulmonary signs (acute infection)

  • Include lupus pernio, pleural effusion, pericarditis, lymphadenopathy.

Extrapulmonary signs (previous/chronic infection)

  • Palpable hard calcified axillary or supraclavicular lymph nodes.

  • Constrictive pericarditis: raised JVP, increase in JVP on inspiration (Kussmaul’s sign), prominent ‘y’ descent in JVP, pericardial knock, pulsatile hepatomegaly, ascites, and peripheral oedema.

  • Spinal TB: thoracic kyphosis or scoliosis.

    • The lumbar or lower thoracic vertebrae are most commonly affected.

    • Compression of the spinal cord by previous TB abscess can lead to a permanent paraplegia.

  • Ocular TB: visual loss, optic atrophy, secondary glaucoma, blue sclera.

  • CNS TB: persisting hydrocephalus, mononeuritis multiplex.

The Extras

Surgery for TB

  • Artificial pneumothorax: air introduced into the pleural space to cause partial collapse of the lung.

  • Phrenic nerve crush: elimination of nerve supply to one hemidiaphragm causing it to relax into the raised position, thereby compressing the apex on the same side and reducing oxygen supply to the infection.

  • Thoracoplasty: removal of rib bones to cause collapse of underlying lung. Most required 7–8 ribs removed in a staged procedure.

  • Plombage: insertion of inert materials into the pleural space in order to collapse the underlying infected lung. Materials included Lucite balls which have a characteristic appearance on radiography.

  • Lobectomy or pneumonectomy: surgical removal of an infected lobe or whole lung.

Showing Off

  • The treatment of pulmonary TB was revolutionized in the 1940s with the discovery of effective chemotherapy:

    • Major and deforming surgery was not uncommon for advanced TB. Procedures declined rapidly in the 1950s.

    • Presently, surgery for TB is usually only indicated for complications such as an empyema, as an aid to uncertain diagnosis, or as an additional treatment for multidrug-resistant TB organisms.

24 Pneumonia

Examination Findings

Inspection

  • Look for sputum pot at bedside.

  • Is patient on oxygen?

  • Tachypnoeic, tachycardic, or hypotensive?

  • Warm peripheries.

  • Bounding pulse.

  • Sweaty and clammy.

Palpation

  • Reduced expansion on the affected side.

  • Increased tactile vocal fremitus if consolidation.

Percussion

  • Dull (but not ‘stony dull’) percussion note of consolidation.

Auscultation

  • Coarse crackles.

  • Bronchial breathing.

  • Whispering pectoriloquy (increased loudness of whispering when listening with stethoscope (see Respiratory OHCEPS for more)).

  • Reduced air entry.

  • Increased vocal resonance.

  • Pleural rub:

    • Sign of pleurisy.

The Essentials

Aetiology

  • The aetiological agent cannot be predicted by clinical presentation alone.

  • Consider the possibility of fungal infection or atypical pathogens (such as Klebsiella, Mycobacterium tuberculosis, or Pneumocystis jirovecii) in patients with known or suspected immunocompromise (e.g. HIV, transplant recipients, those on immunosuppressant therapy or with underlying malignancy).

Differential diagnosis

  • On clinical examination, pneumonia can be difficult to distinguish from:

    • Lower respiratory tract infection (infection without consolidation).

    • Infective exacerbation of COPD (signs of obstructive airways disease).

    • Bronchiectasis (clubbing, copious sputum in the bedside pot).

  • Post-obstructive (associated with a bronchial tumour): look for cachexia, anaemia, clubbing, lymphadenopathy, hepatomegaly, jaundice:

    • British Thoracic Society guidelines recommend a repeat chest radiograph at 6 weeks in patients with persisting symptoms or signs, or those at higher risk of malignancy (smokers or age >50).

The Extras

Complications

  • Parapneumonic effusion: stony dull percussion note, reduced air entry.

  • Empyema: signs of effusion with pyrexia or evidence of chest drain scar.

  • Lung abscess: clubbing, frank pus in sputum pot.

  • Respiratory failure: cyanosis, CO2 retention tremor.

  • Severe sepsis/septic shock: tachycardia, tachypnoea, hypotension, prolonged capillary refill time, cool peripheries, and mottled skin.

Showing Off

Panton–Valentine leucocidin (PVL)

  • An exotoxin associated with some Staphylococcus aureus which causes lysis of leucocytes, increasing the virulence of the S. aureus species.

  • Infection can present with cellulitic and necrotic skin and mucosal lesions but can also manifest as a necrotizing pneumonia associated with a low white cell count which has a mortality of up to 75%.

  • It often affects otherwise healthy children and young adults and its incidence has increased steadily over the last 10 years.

25 Obstructive Sleep Apnoea

While clinical examination is often unrewarding in OSA, it is important not to miss comorbid disease that can present with similar symptoms or disease that may have developed as a consequence.

Examination Findings

Inspection

  • Calculate BMI.

  • Measure neck circumference:

    • If increased, can predict a higher risk of OSA.

  • Assess nasal patency.

  • Look for an abnormally small mandible.

  • Look at the tongue for macroglossia.

  • Look for presence/absence of teeth and dentures.

  • Look at the pharynx for a small lumen size, enlarged tonsils or uvula, and any soft tissue tumours.

  • Check BP as hypertension and OSA are commonly associated.

Palpation

  • Palpate for neck nodes and masses.

Percussion

  • Usually unrevealing but a dull percussion note over the anterior chest wall in a retrosternal thyroid goitre or other anterior mediastinal mass may be evident.

Auscultation

  • Listen for crackles suggesting cardiac failure.

The Essentials

Signs of associated diseases

  • Hypothyroidism (see 112: Hypothyroidism):

    • Dry, thickened skin, hair loss, puffy face, flaking splitting nails, bradycardia, pale conjunctiva of anaemia, palpable/visible goitre.

  • Acromegaly (see 113: Acromegaly):

    • Protrusion of brow and lower jaw, skull enlargement, thickened lips, nose and skin, macroglossia, enlarged ‘spade-shaped’ hands and enlarged feet, bitemporal hemianopia(?), carpal tunnel syndrome.

  • Marfan’s syndrome (see 100: Marfan’s syndrome):

    • Tall, increased arm span, pectus excavatum or pectus carinatum, hypermobile joints, arachnodactyly, long face, high-arched palate, and retrognathia.

  • OSA is also more common in patients with Down’s syndrome.

The Extras

Differential diagnosis

  • Anaemia, COPD, asthma, cardiac failure, underlying malignancy.

Complications arising from OSA

  • Respiratory failure (CO2 retention):

    • Tachypnoea, cyanosis, drowsiness, and asterixis (flapping tremor of outstretched hands). May manifest as early morning headaches and should prompt arterial blood gas sampling.

  • Cor pulmonale:

    • Signs of respiratory distress coupled with a raised JVP, marked hepatojugular reflex, parasternal heave, third or fourth heart sounds, pansystolic murmur of tricuspid regurgitation, peripheral oedema, ascites and jaundice, and pulsatile hepatomegaly.

  • Patients are at higher risk of complications such as stroke, diabetes, and ischaemic heart disease.

Showing Off

  • OSA has previously been known as Pickwickian syndrome after the character Joe ‘the fat boy’ who exhibited classical symptoms of daytime somnolence in Charles Dickens’s first novel The Pickwick Papers published in 1837.

  • The first description of the OSA syndrome in the medical literature did not appear until 1965.

26 Cystic Fibrosis

Examination Findings

Inspection

  • At the bedside:

    • Nebulizer.

    • Sputum pot.

    • Airway clearance devices (e.g. Acapella).

    • Older patients may have non-invasive ventilation at night.

  • Digital clubbing.

  • Low BMI ± short stature.

  • Portacath?:

    • Less frequently a PEG.

  • May be scars of lung or liver transplant.

Auscultation

  • Crackles (may be few):

    • Usually signs most evident anteriorly and apically.

  • Wheeze is common.

The Essentials

Pathophysiology

  • CF is a multisystem disease caused by mutations in a chloride channel gene (the cystic fibrosis transmembrane regulator or CFTR) resulting in impaired salt and water movement across membranes.

  • The most common mutation is ∆F508 (leads to a deletion of a phenylalanine residue at position 508 within the protein).

  • Autosomal recessive inheritance. 1 in 25 Caucasians have CFTR gene mutations, giving 1 in 2500 live births with clinical disease.

  • Viscous secretions lead to:

    • Progressive bronchiectasis, airflow obstruction, and sinusitis.

    • Pancreatic insufficiency requiring enzyme and fat-soluble vitamin supplementation and often insulin.

    • Biliary obstruction.

    • Intermittent distal intestinal obstruction syndrome.

    • Subfertility in females.

    • Respiratory Males are infertile. This is not due to viscous secretion but due to congenital absence of the vas deferens.

The Extras

Mortality

  • Patients are no longer just breathless teenagers.

  • Predicted median lifespan for infants diagnosed with CF is well over 40.

  • Many patients currently function very well in their 30s, and referral for lung transplant is usual as FEV1 declines.

Complications

  • Diabetes is common in adult CF patients, and control is difficult to achieve in the face of altered absorption and recurrent infections.

  • CF-related liver dysfunction and subsequent cirrhosis affects around 10%, and some patients will proceed to liver transplantation.

Infection control

  • Patients are isolated from one another to prevent the transmission of multiresistant Pseudomonas aeruginosa and especially Burkholderia spp. which are difficult to treat and accelerate lung function decline.

Showing Off

  • 5% have CF-related arthritis which may be accompanied by purpura and erythema nodosum.

27 Kartagener’s Syndrome

Kartagener’s syndrome consists of a triad of:

  • Situs inversus (transposition of the viscera).

  • Abnormal frontal sinuses (producing sinusitis).

  • PCD.

Examination Findings

Inspection

  • Digital clubbing?

  • Mucoid rhinorrhoea.

Chest

  • Hyperinflated.

  • Bibasal wheeze.

  • Bibasal crackles.

  • Possibly signs of consolidation.

  • Right-sided apex beat and heart sounds.

Abdomen

  • Left-sided liver.

The Essentials

Primary ciliary dyskinesia

  • Genetically heterogeneous disorders (with autosomal recessive inheritance pattern) that result from the loss of function of a part of the ciliary apparatus, most commonly the dynein arms.

The Extras

Complications

  • Children are often debilitated by their recurrent infections, but morbidity decreases greatly with age and adults are relatively healthy.

  • Recurrent or chronic otitis media are common so otoscopy may reveal a middle ear effusion or grommets and hearing tests show bilateral conductive hearing loss.

  • Transposition of the abdominal organs is not always complete, and patients may have evidence of intervention for diaphragmatic hernia, horseshoe kidney, or polysplenia.

Showing Off

  • Manes Kartagener described a family with dextrocardia, wheeze, and nasal polyps in the 1930s while an intern in Zurich, Switzerland.

  • PCD is now recognized to have a prevalence of 1 in 16,000 with Kartagener’s being half as common.

  • Secondary dyskinesias are common in acute infection, so mucosal biopsies must be obtained when a patient is well to prevent a false-positive result.

Pathophysiology of situs inversus

  • Specialized monocilia lack the microtubules of ordinary motile cilia and so rotate clockwise rather than beat. This normal cilial function in embryo has been shown to generate a net leftward flow at the anterior end of the primitive streak, sweeping the sonic hedgehog protein (SHH) to the left, triggering normal asymmetrical development.

  • In PCD, mutations in the gene for the structural protein left–right dynein (LRD) result in the SHH moving at random and 50% of those affected develop situs inversus where the laterality of the internal organs is the mirror-image of normal.

28 Bronchiectasis

Examination Findings

Inspection

  • Sputum pot:

    • Usually purulent.

    • May be blood-streaked (haemoptysis).

  • Nebulizer or airway clearance device (e.g. Acapella).

  • Digital clubbing may be present.

  • Low BMI.

  • Breathlessness.

  • Central cyanosis?

Auscultation

  • Wheeze:

    • >1/3 of patients.

  • Coarse crackles:

    • ‘Deciduous’ in that the noise falls away.

    • Usually bibasal but can be in any lobe.

The Essentials

Pathophysiology

  • Whatever the precipitant, there is a cycle of:

    • Infection and bronchial oedema.

    • Inflammation and remodelling, hypertrophy and tortuosity of airways and vessels, and neovascularization.

    • Difficulty clearing secretions and increased propensity to acute and chronic infection, and to haemoptysis.

  • Chronic colonization with difficult-to-eradicate (antibiotic-resistant, biofilm-producing) bacteria is usual as patients age.

Causes

  • Genetic (e.g. CF, Marfan’s syndrome, Kartagener’s syndrome).

  • Chronic lung disease (e.g. COPD).

  • Connective tissue disease (1/3 of rheumatoid patients).

  • Chronic inflammatory disease (e.g. inflammatory bowel disease).

  • Chemical damage (e.g. recurrent acid reflux aspiration).

  • Focal bronchial obstruction (e.g. foreign body inhalation, cancer, lymph nodes).

  • Infection (e.g. Klebsiella spp., Staphylococcus aureus, Mycobacterium tuberculosis, Mycoplasma pneumoniae, non-tuberculous mycobacteria, measles virus, pertussis virus, influenza virus, herpes simplex virus).

  • Hypogammaglobulinaemia.

  • Allergic bronchopulmonary aspergillosis.

The Extras

Allergic bronchopulmonary aspergillosis

  • Predominantly proximal and upper lobe bronchiectasis.

  • This exuberant immune response to a ubiquitous fungus usually presents as loss of symptom control in an asthmatic.

  • Mucus plugging is common, and serum eosinophilia with raised specific IgE and IgG (‘precipitins’) are the norm.

  • Treatment is with long-term steroids and antifungals.

29 Superior Vena Cava Obstruction

Examination Findings

Inspection

  • Patient will always prefer to be sat upright.

  • Swollen, plethoric face.

  • Sometimes confused.

  • Stridor:

    • May be present from laryngeal oedema.

  • Engorged, non-pulsatile neck veins.

  • Dilated chest wall veins.

  • Arm swelling:

    • Present but not always striking.

Signs of underlying malignancy

  • Cachexia.

  • Digital clubbing.

  • Supraclavicular lymph nodes.

  • Signs of lobar collapse or of pleural effusion (see 21: Pleural Effusion).

Symptoms

  • Shortness of breath.

  • Head ‘fullness’.

  • Cough.

  • Chest pain.

  • Dysphagia.

  • Orthopnoea.

  • Distorted vision

  • Hoarseness.

  • Headache.

  • Nausea.

  • Light-headedness.

The Essentials

Aetiology

Caused by the obstruction of flow in the SVC from external compression, malignant invasion, or thrombus.

  • 90% of cases caused by:

    • Lung cancer (10% of small cell lung cancers at presentation).

    • Lymphoma.

  • 10% of cases are non-malignant:

    • Thrombus post central line.

    • Aortic aneurysm.

    • Mediastinal fibrosis.

    • Retrosternal goitre.

Investigations

  • In around half of cases, SVC obstruction is the presenting feature. Unless the patient is in extremis, an urgent procedure to obtain histology to allow appropriate treatment to be commenced is preferred to pre-histology radiotherapy.

The Extras

Pemberton’s triad

▶ Not to be tried in patients who already have stridor! Raising the arms above the head induces:

  • Facial plethora.

  • Breathlessness.

  • Stridor.

Showing Off

  • Pemberton’s triad (or sign) is named after Hugh Spear Pemberton, an English physician (1890–1956) who worked in Liverpool. He described the triad in a letter to The Lancet in 1946.

  • Raising the arms above the head is known as ‘Pemberton’s manoeuvre’.

30 Chronic Cor Pulmonale

Examination Findings

Inspection

  • Likely to have supplemental oxygen.

  • Plethoric facies.

  • Central cyanosis.

  • Good peripheral perfusion.

  • CO2 retention flap (asterixis) may be present.

Chest

  • Signs of underlying causative lung problem:

    • Chronic airways disease (COPD is commonest cause).

    • Obesity hypoventilation syndrome.

    • Chest wall deformity.

    • Neuromuscular disorder (chronic hypoventilation).

    • Pulmonary vascular disease (e.g. chronic thromboembolism, vasculitis) is rare.

Cardiac

  • Raised JVP, sometimes giant ‘v’ waves.

  • Widely split second heart sound with loud pulmonary component.

  • May be tricuspid regurgitation murmur.

  • Pitting lower limb oedema.

The Essentials

Definition and aetiology

  • Cor pulmonale refers to the cardiovascular consequences of chronic (almost always type 2) respiratory failure:

    • Pulmonary hypertension.

    • Peripheral vasodilatation and increased vascular permeability (hence oedema) from hypercapnia.

    • Salt and water retention from effect of hypoxia on the kidney and sympathetic stimulation.

    • As vasodilatation and oedema worsen there is stimulation of antidiuretic hormone and renin–angiotensin axis, effectively reduced circulating volume.

The Extras

Cor pulmonale vs right ventricular failure

Respiratory The signs of cor pulmonale are similar but not the same as those of right ventricular failure (despite what some books may say).

  • Right ventricular failure is usually an ischaemic, low-output state from a dilated ventricle giving the following signs:

    • Poor peripheral perfusion.

    • Marked tricuspid regurgitation

    • Hepatomegaly and ascites.

  • Cor pulmonale is a near-normal output state with right ventricular hypertrophy, and although it can progress to right ventricular failure, this is not common without additional ischaemia.

Treatment

  • Treatment involves improving the underlying problem of hypoxia and hypercapnia, including:

    • Supplemental oxygen.

    • Standard medication for any underlying COPD.

    • Non-invasive ventilation (in many cases).

  • Respiratory Unless these measures are instituted first, diuretic therapy will cause intravascular depletion, hypotension, and worsen tissue hypoxia.

  • Often a large diuresis (>10 litres) can be produced without diuretic medication when oxygen and non-invasive ventilation are commenced for long-standing obesity-hypoventilation syndrome.