Respiratory Flashcards
1
Q
What is type 1 respiratory failure?
A
Low PaO2 with normal/low PaCO2
2
Q
What is type 2 respiratory failure?
A
Low PaO2 with raised PaCO2
3
Q
What 3 things can cause a raised alveolar-arterial gradient?
A
- V/Q (ventilation/perfusion) mismatch
- Diffusion limitation
- Shunt (right to left)
4
Q
What causes a normal alveolar-arterial gradient but low PaO2?
A
Low oxygen tension, caused by hypoventilation or reduced FiO2 e.g. at high altitudes
5
Q
What acute adaptations to high altitude does the body make?
A
Increased heart rate
Hyperventilation
6
Q
Give an example of an adaption to chronic high altitude
A
Increase haemoglobin concentration
7
Q
What is high altitude pulmonary oedema?
A
Pulmonary oedema caused by exaggerated hypoxic pulmonary vasoconstriction that can happen to some individuals 2-3 days after ascent.
8
Q
What is the treatment for high altitude pulmonary oedema?
A
Descent, oxygen and pulmonary vasodilators
9
Q
What is the most common monogenic recessive disorder?
A
Cystic fibrosis
10
Q
What are the features of cystic fibrosis?
A
- Abnormal ion transport
- Impaired mucociliary clearance
- Recurrent and chronic infections
- Impaired digestion
- Fertility problems
- Liver disease and diabetes
11
Q
How is obstructive lung disease classified?
A
Low FEV1 (i.e. <80% predicted) FEV1/FVC ratio <0.7
12
Q
How is restrictive lung disease classified?
A
Low FVC (i.e. <80% predicted) FEV1/FVC ratio normal
13
Q
Which type of lung disease affects the airways?
A
Obstructive
14
Q
Which type of lung disease can affect the lung parenchyma and chest wall/pleura?
A
Restrictive
15
Q
What is TLCO?
A
A measurement of the lung’s diffusing capacity (by measuring uptake of CO)
16
Q
What causes low TLCO?
A
- Thickening of the alveolar-capillary membrane
- Reduced lung volumes
17
Q
What causes raised TLCO?
A
- Bronchiectasis
- Pulmonary vasculitis
- Obstructive sleep apnoea
18
Q
In healthy individuals, how much fluid is present in the pleural space?
A
5-10ml
19
Q
What is pneumothorax?
A
Collapse of the lung, caused by the presence of air in the pleural space
20
Q
What are the four categories of pneumothorax?
A
- Primary spontaneous pneumothorax
- Secondary spontaneous pneumothorax
- Traumatic pneumothorax
- Iatrogenic pneumothorax
21
Q
What causes primary spontaneous pneumothorax?
A
Rupture of an apical pleural bleb, which forms a pin-prick size hole. (No underlying lung disease)
22
Q
What are the risk factors for primary spontaneous pneumothorax?
A
Male, smoker, tall and thin, age 20-40
High risk of recurrence
23
Q
What causes secondary spontaneous pneumothorax?
A
- Known lung disease, usually COPD but can also be caused by asthma, ILD, cancer, cystic lung disease.
- Infection (anything that causes cysts in the lungs)
- Genetic predisposition e.g. from Marfan’s syndrome
24
Q
Give some examples of procedures that could lead to iatrogenic pneumothorax
A
Pacemakers, CT lung biopsies, central line insertion, mechanical ventilation, pleural aspiration
25
How can pneumothorax present?
Can be asymptomatic, but can also cause sudden breathlessness, pleuritic chest pain and a cough. Rarely presents with life threatening respiratory failure/cardiac arrest.
26
What are the signs of pneumothorax?
- Small pneumothorax may have no clinical signs
- Tachypnoea
- Hypoxia
- Unilateral chest wall expansion
- Reduced breath sounds
- Hyper-resonant percussion note
27
What potentially life-threatening condition can cause tracheal deviation, surgical emphysema, distended neck veins and cardiovascular compromise?
Tension pneumothorax
28
What causes tension pneumothorax?
A valve-like mechanism forms and air enters the pleural space, increasing pressure in the chest and causing compression and reduced blood flow back to the heart.
29
How is tension pneumothorax managed?
Urgent decompression by inserting cannula then removing the needle, followed by chest drain insertion as longer term measure.
30
What is surgical emphysema?
When air leaks out of the pneumothorax via a breach in the parietal pleura and finds its way under the skin, causing the skin to feel like bubble wrap. Auscultation reveals a crepitus type noise.
31
How is surgical emphysema treated?
By making little cuts in the skin to let the air out
32
What is pleural effusion?
Collection of fluid in the pleural space (will collect at the bottom if patient is sitting up so will show up better on x-ray if patient is upright)
33
What causes pleural effusion?
Imbalance in hydrostatic and oncotic pressure differences, therefore caused by anything that affect oncotic pressures e.g. inflammation.
34
What are the two categories of pleural effusion?
Transudates
| Exudates
35
What is transudative pleural effusion?
Pleural effusion caused by increased hydrostatic pressure or reduced osmotic pressure in microvascular circulation
--> pleural fluid protein <50% of serum protein
36
Give some examples of conditions that can cause transudative pleural effusion
```
Heart failure
Cirrhotic liver disease
Renal failure
Hypoalbuminaemia
Myxoedema (thyroid failure)
Ascites/peritoneal dialysis
Meig's syndrome
```
37
What is exudative pleural effusion?
Pleural effusion caused by increased capillary permeability and impaired reabsorption
--> pleural fluid protein is > 50% of serum protein
38
Give some examples of conditions that can cause exudative pleural effusion
```
Pneumonia
Cancer
TB
Autoimmune conditions e.g. rheumatoid arthritis, SLE
Pulmonary embolism
Asbestos
Post cardiac surgery
Drug induced e.g. amiodarone, beta blockers, methotrexate, phenytoin
```
39
What are the symptoms of pleural effusion?
```
Breathlessness
Cough
Fever
Pain
Others dependent on underlying cause
```
40
What are the signs of pleural effusion?
Reduced chest wall expansion
Quiet breath sounds
'Stony' dull percussion
Reduced tactile/vocal fremitus
Shows up on x-ray once about 250ml of fluid is present
41
How is pleural effusion investigated?
Initial chest x-ray
Thoracic USS with pleural aspiration
CT chest for cysts
Pleural aspirate can be sent for microscopy, culture and cytology.
42
What does turbid/foul smelling pleural aspirate indicate?
Empyema/parapneumonic effusion
43
What does bloodstained pleural aspirate indicate?
Haemothorax/trauma/PE
44
What do food particles in pleural aspirate indicate?
Oesophageal fistula
45
What procedures can be carried out during a medical thoracoscopy for pleural effusion?
Pleural fluid drainage
Biopsies for diagnosis
Talc poudrage for pleurodesis
46
How is pleural effusion managed?
Depends on size, symptoms and underlying cause
- Small --> treat conservatively
- Infection --> antibiotics, chest drain if pus present
- Malignant effusion --> consider chest drain +/- talc
- Treat underlying cause
47
What features of pleural aspirate would suggest infection?
```
Low pH <7.2
Glucose <3.4mmol/L
PF LDH > 1000IU/L
Bacterial growth on culture
Macroscopic appearance of pus (also smell)
```
48
What is empyema?
Pus in the pleural space
49
What organisms are usually responsible for community acquired empyema?
Streptococcus milleri
Streptococcus pneumoniae
Staphylococcus aureus
Anaerobes
50
What organisms are usually responsible for hospital acquired empyema?
MRSA
Staphylococcus aureus
Enterococcus
51
What are the symptoms of empyema?
- Patient feels unwell, not improving
- Swinging fevers/rigor
- Cough/chest pain
52
How is empyema treated?
- Prolonged course of antibiotics
- Chest drain
- Surgery (pleurodesis with talc, indwelling pleural catheter)
53
What is haemothorax?
Blood in the pleural cavity with a haematocrit ratio >50% of that of serum
54
What are some of the possible causes of haemothorax?
```
Trauma
Post-op
Bleeding disorders
Lung cancer
PE
Aortic rupture
Thoracic endometriosis
```
55
How is haemothorax managed?
Large bore chest drain
Possible vascular intervention
?Surgery
56
What is hydropneumothorax?
Fluid and air in the pleural space
57
What are the causes of hydropneumothorax?
Iatrogenic (e.g. introduction of air during pleural aspiration)
Gas forming organisms
Thoracic trauma
58
What causes pleural thickening?
Asbestos
Cancer
Post infection
59
What are the symptoms of oesophageal rupture?
Severe chest pain after vomiting
Dyspnoea
Fever
60
What are the signs of oesophageal rupture?
Surgical emphysema
Pneumothorax
Pleural effusion
61
How is oesophageal rupture managed?
Antibiotics, surgery
62
What are the features of the asthmatic bronchus?
Chronic inflammation
Mucous secretion
Narrowing of airway
Constriction
63
What is atopy?
The tendency to develop IgE mediated reactions to common aeroallergens
64
What are the two types of asthma?
Eosinophilic
| Non-eosinophilic
65
What is eosinophilic asthma?
Severe, more rare type of asthma where TH2 cells activate B cells, resulting in an inflammatory response with mast cell migration and degranulation. Can be atopic or non-atopic.
66
What is non-eosinophilic asthma?
TH1 cells (which normally appear to help fight infection), activates monocytes and macrophages. Triggered by cigarette smoke and pollutants.
67
What other conditions are associated with asthma?
```
Eczema
Hayfever
Nasal disease
Allergies
Reflux disease (irritates airway, can trigger asthma)
```
68
How can asthma be distinguished from COPD?
- COPD tends to occur later in life
- COPD usually caused by smoking
- COPD less variable day to day and diurnally
- COPD more problematic in winter
69
What sort of wheeze might be heard in a patient with asthma (if not well controlled)?
Polyphonic
Expiratory and inspiratory
Widespread
No crackles
70
Asthma may increase responsiveness to which challenge agents?
Mannitol
| Methacholine
71
What might lung function tests show in a person with asthma?
Spirometry may show airway obstruction - reduced FEV1, reduced FEV1/FVC ratio
Bronchodilator reversibility should be present
72
What other conditions can often complicate co-existing asthma?
Bronchiectasis
Breathing pattern disorders
Vocal cord dysfunction
73
What kind of asthma treatments are available?
Bronchodilators (SABA, LABA, leukotriene receptor antagonists, theophyllines)
Anti-inflammatory drugs (steroids)
New biologics (omalizumab, mepolizumab)
74
What is the role of steroids in asthma?
Reduce airway inflammation and decrease mortality risks
75
What kind of asthma are new biologic treatments useful for?
Severe eosinophilic asthma, e.g. omalizumab is anti-IgE injection therapy
76
What is classified as moderate asthma?
PEF 50-75% of best/predicted
| SpO2 > 92%
77
What is classified as acute/severe asthma?
PEF 33-50% of best/predicted
SpO2 > 92%
Respiration > 25
Pulse > 110
Unable to complete sentence in one breath
78
What is classified as life threatening asthma?
```
PEF < 33% best or predicted
SpO2 < 92%
Silent chest, cyanosis, poor respiratory effort
Arrythmia, hypotension
Exhaustion, altered consciousness
```
79
How is a moderate asthma attack managed?
- Give b2 bronchodilator via spacer (one puff every 60s up to 10 puffs) to see if PEF > 75%
- -> monitor for 2 hours, consider discharge
- If not, follow acute severe asthma protocol
80
How is acute severe asthma managed?
- Give b2 bronchodilator via oxygen-driven nebuliser
- Repeat and give 40-50mg oral prednisolone if PEF remains < 75%
- If PEF > 75% after first dose of nebulised salbutamol, monitor for 2 hours and consider discharge
- Observe and monitor for signs of severe asthma or PEF < 50%
81
How is life threatening asthma managed?
- Immediately give O2 and nebulised b2 bronchodilator with ipratropium and steroids (oral prednisolone/IV hydrocortisone)
- Check ABGs
- Repeat nebuliser after 15 minutes (may need continuous nebuliser)
- Consider IV magnesium sulphate
- Correct fluid/electrolytes
- Chest x-ray
- Repeat ABG
- Admit patient
82
What are the two main categories of bronchodilators?
1. Adrenergic - act via sympathetic system to cause bronchodilation
2. Anticholinergic - block parasympathetic pathways, thereby blocking bronchoconstriction
83
How do beta-2 adrenoreceptor agonists work?
Act on beta2 adrenoreceptors to cause smooth muscle relaxation in the airways and inhibit histamine release from lung mast scells
84
Name a short-acting beta agonist
Salbutamol
85
Name a long acting beta agonist
Formoterol
| Salmeterol
86
Name an ultra long acting beta agonist (once daily)
Indacaterol
| Olodaterol
87
How do anticholinergics work?
Prevent ACh from binding to muscarinic receptors in airway smooth muscle, thereby preventing bronchoconstriction.
88
Atropine is a naturally occurring anticholinergic. What are the newer synthetic derivatives of atropine?
Ipratropium bromide
| Tiotropium bromide
89
How do inhaled corticosteroids reduce inflammation in asthma patients?
- Suppressing the production of chemotactic mediators (thus preventing recruitment of inflammatory cells such as neutrophils and eosinophils)
- Reduce adhesion molecule expression
- Inhibit inflammatory cell survival in the airway
90
What long term side effects can occur as a result of overuse of corticosteroids?
Loss of bone density
Adrenal suppression
Cataracts, glaucoma
91
What types of drugs can be used to help treat more severe inflammatory lung disease?
Monoclonal antibodies e.g. anti-TNF alpha
92
What is bronchiectasis?
An obstructive lung disease whereby abnormal dilation of the bronchi results in excessive sputum production, chest pain and increased likelihood of infection
93
What disease is bronchiectasis commonly associated with?
Cystic fibrosis
94
How is bronchiectasis treated?
- Antibiotics to treat infections
- Physical therapy to clear airways
- Mucolytics to treat hypersecretion
- Severe disease may require surgical intervention
95
What is the hallmark of interstitial lung diseases?
Fibrosis
96
What is the interstitium of the lung?
A network of tissue that extends through the lungs and supports the alveoli
97
Name 4 interstitial lung diseases
Idiopathic pulmonary fibrosis
Interstitial pneumonia
Hypersensitivity pneumonitis
Sarcoidosis
98
Why do interstitial lung diseases generally present with cough and/or breathlessness on exertion?
Due to impaired gas exchange caused by thickening of the interstitium
99
What is thought to be the mechanism behind idiopathic pulmonary fibrosis?
Activated lung epithelium produces mediators of fibroblast migration, proliferation and differentiation into active myofibroblasts, which then secrete loads of ECM that remodels the lung architecture.
100
What are two new drugs that slow the progression of idiopathic pulmonary fibrosis?
Pirfenidone
| Nintedanib
101
How does pirfenidone slow the progression of IPF?
Reduces fibroblast proliferation, collagen production and the production of fibrogenic mediators
102
How does nintedanib work?
Tyrosine kinase inhibitor
| Inhibits VEGFR and other growth factor receptors, which drive fibrotic process.
103
What features are present in interstitial lung disease?
1. Restriction of lung volume (measured by FVC)
2. Reduction in lung gas transfer efficiency (TLCO)
3. Hypoxia
4. Reduction in exercise capacity
104
What happens in hypersensitivity pneumonitis?
Lymphocytes produce antibodies (including IgG) in response to antigens. IgG bound to antigen can be deposited in the airways and not adequately cleared, resulting in a type III hypersensitivity reaction
105
What test is useful for distinguishing hypersensitivity pneumonitis from other interstitial lung diseases?
Lymphocytes in bronchoalveolar lavage
106
What might a CT scan show in a patient with hypersensitivity pneumonitis?
White nodules (collections of inflammatory lymphocytes)
107
How is hypersensitivity pneumonitis treated?
Identification and removal of antigen if possible
Steroids for acute/subacute disease
Nintedanib slows rate of decline
108
What autoimmune connective tissue disorder can cause interstitial lung disease?
Systemic sclerosis
109
What can be used to treat patients with systemic sclerosis with interstitial lung disease?
Cyclophosphamide with nintedanib to reduce progression of disease
110
What are the most common culprits of drug-induced interstitial lung disease?
Nitrofurantoin
Methotrexate
Amiodarone
Bleomycin
111
What is typically heard on auscultation in IPF (and sometimes other ILDs)?
Bibasal crackles
112
What are the symptoms of COPD?
Morning 'smokers' cough and sputum
Progressive dyspnoea on exertion
Wheeze/noisy breathing
Ankle swelling
113
What are the signs of COPD?
Pursed lips
Accessory muscles used to support ventilation
Increased respiratory rate
Hyperexpanded chest with decreased expansion
End expiratory wheeze
Cyanosis
Weight loss
Signs of cor pulmonale e.g. increased JVP, ankle swelling
114
What are the causes of COPD?
1. Cigarette smoking
2. Occupational e.g. coal dust
3. Alpha-1 antitrypsin deficiency
115
Give 5 causes of respiratory failure
1. Low oxygen delivery (e.g. high altitude)
2. Airway obstruction (e.g. asthma, COPD)
3. Gas exchange/diffusion limitation (e.g. lung fibrosis)
4. Ventilation/perfusion mismatch (e.g. pneumonia, PE, pulmonary hypertension)
5. Alveolar hypoventilation (e.g. emphysema, muscular weakness, reduced respiratory drive)
116
Give 3 causes of acidaemia
1. Increased CO2 production (ventilatory failure)
2. Loss of HCO3- (e.g. salicylate poisoning)
3. Increase in H+ production (e.g. ketoacidosis, Kussmaul breathing)
117
Why does obstructive sleep apnoea occur?
The supine position increases the passive load on the thorax, diaphragm is not aided by gravity
118
Why does obstructive sleep apnoea cause fatigue?
Blood O2 levels drop, rise in CO2 is detected, which leads to arousal - can happen several times a night
119
What is the treatment for obstructive sleep apnoea?
CPAP (continuous positive airway pressure)
| Air is blown into the nasopharynx, holding the airway open
120
What is CPAP used for other than OSA?
Type 1 respiratory failure
Acute cardiac failure
Covid pneumonitis
121
What is BiPAP?
Non-invasive ventilation that delivers two pressures, for breathing in and out (increased pressure on inhalation, decreased pressure on exhalation).
122
When is BiPAP used?
```
Type 2 respiratory failure
COPD
Neuromuscular disease
Obesity hyperventilation syndrome (where CPAP fails)
Chest wall deformity
```
123
Why are individuals with defective swallowing more prone to respiratory tract infection?
Pathogens are usually swallowed rather than spat out and are destroyed as a result.
124
Apart from impaired swallowing, what other factors increase susceptibility to respiratory tract infections?
- Colonisation of upper airway with certain bacteria
- Altered lung physiology e.g. CF, bronchiectasis, emphysema, ILD, spinal disease, weakness, obesity, surgery
- Immune dysfunction e.g. immunodeficiency, immunosuppression
125
What complications can occur as a result of upper respiratory tract illnesses?
```
Sinusitis
Pharyngitis
Otitis media
Bronchitis
Pneumonia (rarely)
```
Systemic symptoms (particularly influenza and covid)
126
What usually causes pharyngitis?
Viruses such as rhinovirus, adenovirus
| Can also be caused by EBV, acute HIV infection
127
Most individuals are vaccinated against corynebacterium diphtheria. When should this be suspected in unvaccinated individuals?
If a greyish membrane is seen on the tonsils.
128
How is corynebacterium diphtheria infection treated?
Antitoxin
| Clarithromycin/erythromycin
129
What are the Centor criteria?
Criteria to indicate the likelihood of a sore throat being due to bacterial infection:
- Tonsillar exudate
- Tender anterior cervical adenopathy
- Fever >38C
- Absence of cough
Positive predictive value 40-60% if 3/4 criteria met
130
Sinusitis is usually viral. Which bacteria can also cause it?
Strep pneumoniae
| Haemophilus influenzae
131
What sign is seen on x-ray to denote acute epiglottitis?
"Thumb sign" on lateral view
132
How does epiglottitis present?
Inspiratory stridor due to blocked airway
133
What usually causes epiglottitis?
Hib - used to be common in young children but now rare due to vaccine
134
What antimicrobials can be used to treat Hib infections?
Doxycycline or co-amoxiclav
| 20% produce beta-lactamases, not susceptible to macrolides
135
What does Bordatella pertussis look like on culture?
Gram negative bacillus
136
How is Bordatella pertussis diagnosed?
Culture
PCR
ELISA for IgG against pertussis toxin
137
How does Bordatella pertussis present?
1-2 weeks catarrhal phase with rhinorrhoea and conjunctivitis
1-6 weeks paroxysmal phase with coughing spasms, inspiratory 'whoop', vomiting and cough lasting >14 days
138
What antibiotic is used to treat Bordatella pertussis?
Clarithromycin
139
What is croup?
Acute laryngotracheobronchitis
140
What normally causes croup?
Most commonly parainfluenza virus
| also RSV, influenza A and other 'respiratory' viruses
141
What is pneumonia?
Inflammation of the lungs
142
Which groups of people are most at risk of pneumonia?
- Infants and the elderly
- COPD and other chronic lung diseases
- Nursing home residents
- Impaired swallow (e.g. from neurological conditions)
- Diabetes
- Congestive heart disease
- Alcoholics and intravenous drug users
143
Describe the pathogenesis of pneumonia
If macrophages in the alveoli become overwhelmed by pathogens, they recruit neutrophils to the site, resulting in collateral damage. The alveoli become inflamed and filled with pus.
144
What does rust-coloured sputum suggest?
Strep pneumoniae infection
145
What signs may be present on percussion and auscultation in patients with pneumonia?
```
Dullness on percussion
Decreased air entry
Bronchial breath sounds
Crackles +/- wheeze
Increased vocal resonance
```
146
What investigations should be carried out for pneumonia?
```
Chest x-ray
FBC
U&E
CRP
Pulse oximetry
Microbiological tests (sputum culture)
```
147
What is lung consolidation?
When the small airways in the lungs get filled with something other than air
148
What should you always test for when a patient presents with pneumonia?
HIV
149
What features indicate severe pneumonia?
Features of sepsis:
- Vasodilation
- Reduced BP
- Impaired oxygen perfusion
- Tissue hypoxaemia
- Delirium/confusion
- Renal impairment (increased urea)
- Increased oxygen demand (high respiratory rate)
150
What scoring system is used to assess the severity of community-acquired pneumonia?
```
CURB65 (or CRB65 if urea not available)
One point for:
- Confusion
- Urea > 7mmol
- Respiratory rate > 30/min
- BP low (systolic <90 or diastolic <60)
- Age >65
```
If patient is 2+ admit to hospital
If patient is 4/5, admit to critical care
151
S pneumoniae is a gram positive coccus that is the most common cause of pneumonia requiring hospitalisation in the UK. Which antibiotics is it sensitive to?
Beta lactams - amoxicillin
Cephalosporins - cefuroxime, cefotaxime
Also macrolides - clarithromycin
Also fluoroquinolones - ciprofloxacin
152
Klebsiella pneumoniae is a gram negative bacillus that is associated with hospital acquired pneumonia and is more prevalent amongst homeless individuals and alcoholics. Which antibiotics is it sensitive to?
Co-amoxiclav
Also, cephalosporins (ceftriaxone, cefotaxime)
153
Mycoplasma pneumoniae causes epidemics every four years and is usually found in younger adults. What extrapulmonary features are sometimes found?
- Haemolytic anaemia
- Raynaud's
- Bullous myringitis
- Encephalitis
- Erythema multiforme
154
What pneumonia-causing organism is often found in still, warm water?
Legionella
155
What extra-pulmonary features may be seen in a patient with pneumonia caused by Legionella?
- Diarrhoea
- Abnormal LFTs
- Hyponatraemia
- Myalgia
- Raised creatinine kinase
- Interstitial nephritis
- Encephalitis
- Confusion
156
What microbiological tests can be performed to ascertain the cause of pneumonia?
- Sputum culture and sensitivities
- Blood culture
- Serology
- Urinary antigen
- PCR for viruses
- Consider AFB stain and culture if suggestive of TB
157
Which antibiotics can be given empirically in the case of mild community-acquired pneumonia (CRB65 0-1)?
Amoxicillin (because it's probably S pneumoniae)
| Clarithromycin/doxycycline if patient is allergic to penicillin
158
Which antibiotics can be given empirically for moderate severity (CURB65 2) pneumonia?
Amoxicillin + clarithromycin
159
Which antibiotics can be given empirically for severe pneumonia (CURB65 3-5)?
IV co-amoxiclav + clarithromycin
Alternatively cefuroxime + clarithromycin
160
Which patients are most at risk of lung abscesses?
- Alcoholics
- Poor dentition
- Aspirators
161
Which organisms tend to cause lung abscesses?
Strep milleri
Anaerobes
Klebsiella pneumoniae
Other gram negative bacteria
162
What is the definition of hospital-acquired pneumonia?
Pneumonia acquired at least 48 hours after hospital admission.
163
Who are most at risk of hospital-acquired pneumonia?
- Elderly
- Ventilated patients
- Post-op patients
164
What antibiotics would you normally start with for treatment of hospital-acquired pneumonia?
Doxycycline + piperacillin-tazobactam (or cefuroxime)
165
What antibiotics can be given if MRSA is suspected?
Linezolid or vancomycin
166
What antibiotics can be given as a last resort for treatment of hospital-acquired pneumonia if patient fails to improve?
Meropenem
| IV colistin can be given for multi-drug resistant gram negatives
167
Which virus causes 80% of bronchiolitis infections?
Respiratory syncytial virus
168
What are the symptoms of acute bronchitis?
- Cough +/- phlegm and breathlessness caused by inflammation of the bronchial epithelium
- Wheeze often present
- No fever/other systemic features
- No signs of consolidation
169
What pathogens usually cause acute bronchitis?
Usually viruses e.g. adenoviruses, RSV
170
What are the local symptoms of lung cancer?
- Cough
- Increasing shortness of breath
- Recurrent chest infections
- Haemoptysis
171
What are the systemic symptoms of lung cancer?
- General malaise
- Weight loss
- Paraneoplastic syndrome
172
What is paraneoplastic syndrome?
Syndrome affecting 3-10% of lung cancer patients, which results in inappropriate secretion of various hormones (ADH, ACTH, PTH etc).
173
What are the possible complications of paraneoplastic syndrome?
- Periostitis, digital clubbing, painful arthropathy
- Myaesthenic syndrome (LEMS)
- Finger clubbing
- Migratory thrombophlebitis
- Non-infective endocarditis
- Disseminated intravascular coagulation
174
What proportion of lung tumours are carcinomas?
90%
175
Non small cell lung carcinomas make up around 85% of primary lung carcinomas. What are the 3 main types?
1. Adenocarcinoma
2. Squamous cell carcinoma
3. Large cell carcinoma
176
What is the gold standard treatment for non small cell lung carcinoma?
Resection of tumour and lymph nodes +/- chemotherapy
177
What can be seen on histological examination of squamous cell carcinomas?
Balls of keratin
178
What can be seen on histological examination of adenocarcinomas?
Glandular structures e.g. small lumens
179
How do small cell carcinomas appear on histology?
"All nuclei" - high grade, aggressive neoplasm
180
What is the primary treatment for small cell lung carcinoma?
Urgent chemotherapy
181
What is a carcinoid tumour?
A neuroendocrine tumour with malignant potential - can be surgically excised to prevent malignant change
182
How is lung cancer definitively diagnosed?
Biopsy for histology - can be retrieved via bronchoscope, CT-guided biopsy, FNA
183
What are the risks of lung tumour biopsy?
Pneumothorax
| Haemorrhage
184
What system is used to stage lung cancers?
TNM staging
T1-4
N1-2
M0-1
185
What are the two main primary tumours of the pleura?
1. Pleural fibroma (localised tumour of the pleura)
| 2. Mesothelioma (malignant)
186
What is the most common cause of mesothelioma?
Asbestos
187
What is the hallmark of TB?
Bloodstained phlegm
188
How can you catch TB?
- Breathing in droplets from an infected person
| - Drinking unpasteurised milk from a cow with TB (Mycobacterium bovis)
189
How does the immune system deal with a TB infection?
Alveolar macrophages make contact with the bacilli, macrophages activated, granulomata form predominantly in lung apex, where macrophages and lymphocytes seal in and contain bacilli, killing the majority of them.
190
What happens in 2-5% of individuals with TB?
- Granuloma grows and develops into a cavity
- Bacilli and macrophages coalesce to form a granuloma called the primary (ghon) focus
- Mediastinal lymph nodes enlarge
- Primary focus + mediastinal lymph node = Ghon complex
- Primary pulmonary disease develops
191
What are the systemic features of TB?
- Weight loss
- Low grade fever
- Anorexia
- Night sweats
- Malaise
192
What are the features of pulmonary TB?
- Chronic cough (at least 3 weeks)
- Chest pain
- Breathlessness
- Haemoptysis
193
How can TB result in pleural effusion?
If the focus ruptures into the pleural space
194
What can happen if TB is not contained?
It can spread beyond the lungs via haematogenous dissemination, leading to e.g. TB meningitis, miliary TB, pleural TB, bone and joint TB, genitourinary TB
195
What is miliary TB?
TB that goes everywhere all at once
196
What might blood results show in active TB?
- Normochromic normocytic anaemia
- Thrombocytosis
- Raised ESR/CRP
- Hypoalbuminaemia
- Hypercalcaemia
197
What is the definitive test for TB?
Acid-fast bacilli detected in sputum/urine/CSF/pleural fluid or in biopsy specimen (e.g. lymph nodes)
198
What tests are used to diagnose latent TB?
'Mantoux' tuberculin skin test - stimulates type 4 delayed hypersensitivity reaction
Interferon gamma release assay (IGRA)
- better than Mantoux
- demonstrates exposure to M tuberculosis
199
What is the standard treatment for TB?
```
RIPE
Rifampicin
Isoniazid
Pyrazinamid
Ethambutol
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All four for 2 months, R and I for further 4 months
