Respiratory Flashcards
1
Q
What centres and receptors are involved in respiration?
A
- Central regulatory centres
- Central and peripheral chemoreceptors
- Pulmonary receptors
2
Q
where are three respiratory regulatory centres?
A
- Medullary respiratory centre
- Apneustic centre (lower pons)
- Pneumotaxic centre (upper pons)
3
Q
Describe how central and peripheral chemoreceptors cause respiration?
A
- Central: raised [H+] in ECF stimulates respiration
* Peripheral: carotid + aortic bodies, respond to raised pCO2 & [H+], lesser extent low pO2
4
Q
Describe the three types of pulmonary receptors and how these affect respiration?
A
- Stretch receptors, lung distension causes slowing of respiratory rate (Hering-Bruer reflex)
- Irritant receptor, leading to bronchoconstriction
- Juxtacapillary receptors, stimulated by stretching of the microvasculature
5
Q
What is the ‘chloride shift’ in respiration?
A
- CO2 diffuses into RBCs
- CO2 + H2O —- carbonic anhydrase -→ HCO3- + H+
- H+ combines with Hb
- HCO3- diffuses out of cell,- Cl-replaces it
6
Q
What is the bohr effect?
A
• Increasing acidity (or pCO2) means O2 binds less well to Hb
7
Q
What is the haldane effect?
A
• ↑ pO2 means CO2 binds less well to Hb
8
Q
what does tidal volume mean? how much is it males/female?
A
- Volume inspired or expired with each breath at rest
* 500ml in ♂s, 350ml in ♀s
9
Q
What is the inspiratory reserve volume in L? what volume is this?
A
Inspiratory Reserve Volume (IRV) = 2-3 L
• Maximum volume of air that can be inspired after normal tidal inspiration
• Inspiratory capacity = TV + IRV
10
Q
what is the Expiratory Reserve Volume (ERV) in L? what does this mean?
A
Expiratory Reserve Volume (ERV) = 750ml
• Maximum volume of air that can be expired after normal tidal expiration
11
Q
what is the residual volume? how much is this in L?
A
Residual volume (RV) = 1.2L
• Volume of air remaining after maximal expiration
• ↑ with age
• RV = FRC – ERV (Functional Residual Capacity - Expiratory Reserve Volume)
12
Q
what is the vital capacity? how much is this in L?
A
Vital Capacity (VC) = 5L • Maximum volume of air that can be expired after a maximal inspiration • 4,500ml in ♂s, 3,500 mls in ♀s • ↓ with age • VC = IC + ERV
13
Q
What is FVC?
A
forced vital capacity
This is the volume of air that can forcibly be blown out after full inspiration, measured in liters.
14
Q
What is FEV1?
A
Forced expiratory volume in 1 second
This is the maximum volume of air that can forcibly blow out in the first second during the FVC manoeuvre, measured in liters. Along with FVC it is considered one of the primary indicators of lung function.
15
Q
What is the FEV1/FVC
A
This is the ratio of FEV1 to FVC. In healthy adults this should be approximately 75–80%.
16
Q
What is the PEF?
A
Peak expiratory flow
This is the maximal flow (or speed) achieved during the
maximally forced expiration initiated at full inspiration,
measured in liters per second.
17
Q
what is FEF 25–75% or 25–50%?
A
Forced expiratory flow 25-75% or 25-50%
This is the average flow (or speed) of air coming out of the lung during the middle portion of the expiration (also sometimes referred to as the MMEF, for maximal mid-expiratory flow).
18
Q
What is FIF 25–75% or 25–50%?
A
This is similar to FEF 25–75% or 25–50% except the
measurement is taken during inspiration.
19
Q
What is FET?
A
Forced Expiratory Time This measures the length of the expiration in seconds.
20
Q
What is SVC?
A
Slow Vital capacity
Maximum volume of air that can be exhaled slowly after slow maximum inhalation.
21
Q
What is MVV?
A
Maximum Voluntary Ventilation
A measure of the maximum amount of air that can be inhaled and exhaled in one minute, measured in liters/minute.
22
Q
What is FRC?
A
functional residual capacity FRC The amount of air left in the lungs after a tidal breath out. The amount of air that stays in the lungs during normal breathing. ERV+RV = 2.4 / 1.9 L
23
Q
What happens in PFTS in obstructive lung disease?
A
FEV1 - significantly ↓
FVC - ↓ or normal
(FEV1/FVC) - ↓
24
Q
What happens in PFTs in restrictive lung disease?
A
FEV1 - ↓
FVC - significantly ↓
(FEV1/FVC) - normal or ↑
25
what is lung compliance?
is defined as change in lung volume per unit change in airway pressure
26
what are 2 causes of increased compliance?
Causes of ↑ compliance
• Age
• Emphysema
27
What are causes of decreased compliance in the lungs?
```
Causes of ↓ compliance
• Pulmonary edema
• Pulmonary fibrosis
• Pneumonectomy
• Kyphosis
```
28
Describe what happens to Hb saturations if the oxygen saturation curve shifts right?
Shifts to right = for given oxygen tension there is ↓ saturation of Hb with oxygen i.e. Enhanced
oxygen delivery to tissues
Left shift of the curve is a sign of hemoglobin's ↑ affinity for oxygen (eg. at the lungs). Similarly, right
shift shows ↓ affinity,
29
Describe what happens to Hb saturations if the oxygen saturation curve shifts left?
Shifts to left = for given oxygen tension there is ↑ saturation of Hb with oxygen i.e. ↓ oxygen
delivery to tissues
Left shift of the curve is a sign of hemoglobin's ↑ affinity for oxygen (eg. at the lungs). Similarly, right
shift shows ↓ affinity,
30
Describe 4 things that shift oxygen dissociation right?
```
Shifts to Right = Raised oxygen delivery
• Raised [H+] (acidity)
• Raised PCO2
• Raised 2,3-DPG
• Raised temperature
```
31
Describe 5 things that shift oxygen dissocation left?
```
Shifts to Left = Lower oxygen delivery
• HbF, methemoglobin, carboxyhemoglobin
• Low [H+] (alkali)
• Low PCO2
• Low 2,3-DPG
• Low temperature
```
32
What is transfer factor?
The transfer factor describes the rate at which a gas will diffuse from alveoli into blood. Carbon
monoxide is used to test the rate of diffusion. Results may be given as the total gas transfer (TLCO) or
that corrected for lung volume (transfer coefficient, KCO)
33
what are 6 causes for a raised TLCO?
```
Causes of a raised TLCO
• Asthma
• Pulmonary hemorrhage (wegener's, goodpasture's)
• Left-to-right cardiac shunts
• Polycythemia
• Hyperkinetic states
• ♂ gender, exercise
```
34
what are 7 causes for a low TLCO?
```
Causes of a lower TLCO
• Pulmonary fibrosis
• Pneumonia
• Pulmonary emboli
• Pulmonary edema
• Emphysema
• Anemia
• Low cardiac output
```
35
what conditions may cause ↑ KCO with a normal or ↓ TLCO?
KCO also tends to ↑ with age (used to diagnose or R/O interstitial lung disease). Some conditions may
cause ↑ KCO with a normal or ↓ TLCO
• Pneumonectomy/lobectomy
• Scoliosis/kyphosis
• Neuromuscular weakness
• Ankylosis of costovertebral joints e.g. Ankylosing spondylitis
36
what happens to pulmonary arteries in the presence of hypoxia?
A fall in the partial pressure of oxygen (pO2) in the blood leads to vasoconstriction of the pulmonary
arteries. This allows blood to be divered to better aerated areas of the lung and improves the efficiency
of gaseous exchange
37
describe some contraindications to thoracentesis?
An uncooperative patient or coagulation disorders that can not be corrected are absolute
contraindications.
```
Relative contraindications include cases in which the site of insertion has known bullous disease (e.g.
emphysema), use of positive end-expiratory pressure (PEEP, in mechanical ventilation) and only one
functioning lung (due to diminished reserve). The aspiration should not exceed 1L as there is a risk of
development of pulmonary edema.
```
38
name some causes of asthma
```
The following can cause Asthma:
• Isocyanates - the most common cause. Example occupations include spray painting and foam moulding using adhesives
• Platinum salts
• Soldering flux resin
• Glutaraldehyde
• Flour
• Epoxy resins
• Proteolytic enzymes
```
39
describe features that would increase the probability of asthma diagnosis
• Wheeze, breathlessness, chest tightness and
cough, worse at night/early morning
• History of atopic disorder
• Wheeze heard on auscultation
• Unexplained peripheral blood eosinophilia
40
describe some features that would reduce the probability of asthma
• Prominent dizziness, light-headedness, peripheral
tingling
• Chronic productive cough in the absence of
wheeze or breathlessness
• Repeatedly normal physical examination
• Significant smoking history (i.e. > 20 pack-years)
• Normal PEF or spirometry when symptomatic
41
What investigation would you do if a patient had an intermediate probability of asthma?
For patients with an intermediate probability of asthma further investigations are suggested. The
guidelines state that spirometry is the preferred initial test:
• FEV1/FVC < 0.7: trial of treatment
• FEV1/FVC > 0.7: further investigation/consider referral
42
When would a >400ml improvement in FEV1 be significant?
A > 400 ml improvement in FEV1 is considered significant
• Before and after 400 mcg inhaled salbutamol in patients with diagnostic uncertainty and airflow
obstruction present at the time of assessment
• If there is an incomplete response to inhaled salbutamol, after either inhaled corticosteroids
(200 mcg twice daily beclomethasone equivalent for 6-8 weeks) or oral prednisolone (30 mg
once daily for 14 days)
43
How is peak flow interpreted in Asthma?
It is now advised to interpret peak flow variability with caution due to the poor sensitivity of the test
• Diurnal variation % = [(Highest – Lowest PEFR) / Highest PEFR] x 100
• Assessment should be made over 2 weeks
• Greater than 20% diurnal variation is considered significant
44
How is complete control of asthma defined as?
The aim of asthma management is control of the disease. Complete control is defined as:
• no daytime symptoms
• no night-time awakening due to asthma
• no need for rescue medication
• no asthma attacks
• no limitations on activity including exercise
• normal lung function (in practical terms FEV1 and/or PEF >80% predicted or best)
• minimal side effects from medication.
45
Describe the inital therapy for asthma
Prescribe an inhaled short-acting β2 agonist as short-term reliever therapy for all patients with symptomatic asthma.
Inhaled corticosteroids are the recommended preventer drug for adults and children for achieving overall treatment goals.
Give inhaled corticosteroids initially twice daily (except ciclesonide which is given once daily).
Once-a-day inhaled corticosteroids at the same total daily dose can be considered if good control is established.
Clinicians should be aware that higher doses of inhaled corticosteroids may be needed in patients who are smokers or ex-smokers
46
Describe the initial add on therapy for asthma after initial therapy is established
SABA + low-dose ICS + leukotriene receptor antagonist (LTRA)
47
Describe the secondary add on therapy for asthma after initial therapy has started and initial add on therapy has been trialled
SABA + low-dose ICS + long-acting beta agonist (LABA)
Continue LTRA depending on patient's response to LTRA
48
what should be considered in patients which excersize is a specific problem in asthma?
If exercise is a specific problem in patients taking inhaled corticosteroids who are otherwise well controlled, consider adding one of the following therapies:
• leukotriene receptor antagonists
• long-acting β2 agonists
• sodium cromoglicate or nedocromil sodium • theophyllines.
Immediately prior to exercise, inhaled short-acting β2 agonists are the drug of choice.
49
Describe the stages of COPD
1 - mild FEV1 >80% of predicted
2- moderate FEV1 50-80%
3- severe 30-49% FEV1
4- very severe <30% FEV1
50
What vaccinations are used in COPD?
* Annual influenza vaccination
| * Pneumococcal vaccination
51
What is the initial COPD therapy
Bronchodilator therapy
• Short-acting β2-agoinst (SABA) or short-acting muscarinic antagonist (SAMA) is 1st line Rx.
Salbutamol/ipratropium
52
How is further management of COPD after inital therapy determined?
FEV1
53
If the FEV1 is more than 50% but patient is still need add on COPD therapy what can be used?
• Long-acting β2-agoinst (LABA), for
example salmeterol, or:
• Long-acting muscarinic antagonist
(LAMA), for example tiotropium
54
If the FEV1 is less than 50% in COPD what is the further treatment?
FEV1 < 50% (stage III and IV)
• LABA + inhaled corticosteroid (ICS) in a
combination inhaler, or:
• LAMA
55
when should oral theophylline be used in COPD?
• NICE only recommends theophylline after trials of short and long-acting bronchodilators or to
people who cannot use inhaled therapy
• The dose should be reduced if macrolide or fluroquinolone antibiotics are coprescribed
56
What are the features of cor pulmonale?
• Features include peripheral oedema, raised
JVP, systolic parasternal heave, loud P2
• Use a loop diuretic for oedema, consider
long-term oxygen therapy
• ACE-inhibitors, calcium channel blockers
and alpha blockers are NOT recommended
by NICE
57
When should COPD patients be assessed for LTOT?
```
The 2010 NICE guidelines on COPD clearly
define which patients should be assessed for and
offered long-term oxygen therapy (LTOT).
Patients who receive LTOT should breathe
supplementary oxygen for at least 15 hours a day.
Assess patients if any of the following:
• Very severe airflow obstruction (FEV1 <
30% predicted). Assessment should be
'considered' for patients with severe
airflow obstruction (FEV1 30-49%
predicted)
• Cyanosis
• Polycythaemia
• Peripheral oedema
• Raised jugular venous pressure
• Oxygen saturations ≤ 92% on room air
```
58
What is included in the assessment of COPD patients for LTOT?
Assessment is done by measuring arterial blood
gases on 2 occasions at least 3 weeks apart in
patients with stable COPD on optimal
management.
Offer LTOT to patients with a pO2 of < 7.3 kPa or
to those with a pO2 of 7.3 - 8 kPa and one of the
following:
• Secondary polycythaemia
• Nocturnal hypoxaemia
• Peripheral oedema
• Pulmonary hypertension
59
What are the benefits of LTOT?
• ↓ secondary polycythemia
• ↓ sympathetic activity → ↓ cardiac
arrhythmia
• Improve sleep quality
60
what is emphysema? what is seen on PFTs?
Emphysema is an irreversible degenerative
condition; it is a known complication of COPD.
• ↑ Residual Volume (RV)
• ↑ Total Lung Capacity (TLC)
• Giving typical obstructive pathology
61
what is seen on CXR of patients with emphysema?
* Flattening of diaphragms: ↑ lung volumes
* Enlarged left pulmonary artery
* Attenuation of vessels
* Diffuse hyperlucency
62
what is panacinar emphysema?
Panacinar (panlobular): entire respiratory
acinus, from respiratory bronchiole to alveoli,
is expanded. > In the lower lobes.
63
what is centriacinar emphysema?
Centriacinar (centrilobular): respiratory
bronchiole (proximal and central part of the
acinus) is expanded. The distal acinus or
alveoli are unchanged. > In the upper lobes.
64
What is congenital lobar emphysema?
Congenital lobar emphysema (CLE): results in
overexpansion of a pulmonary lobe and
resultant compression of the remaining lobes of
the ipsilateral lung, and possibly contralateral
lung. There is bronchial narrowing because of
weakened or absent bronchial cartilage. There
may be congenital extrinsic compression,
commonly by an abnormally large pulmonary
artery. CLE is potentially reversible, yet
possibly life-threatening, causing respiratory
distress in the neonate.
65
what is paraseptal emphysema?
Paraseptal emphysema: involves the alveolar
ducts and sacs at the lung periphery. The
emphysematous areas are subpleural in
location and often surrounded by interlobular
septa (hence the name). It may be an incidental finding in young adults, and may be associated
with spontaneous pneumothorax. It may also
be seen in older patients with centrilobular
emphysema. Both centrilobular and paraseptal
emphysema may progress to bullous
emphysema.
66
What is emphysematous bulla?
Emphysematous Bulla is defined as being at least
1 cm in diameter, and with a wall less than 1mm
thick. Bullae are thought to arise by air trapping in
emphysematous spaces, causing local expansion
67
How do you manage COPD patients in the acute scenario with oxygen?
Prior to the availability of blood gases, use a 28% Venturi mask at 4 l/min and aim for an
oxygen saturation of 88-92% for patients with risk factors for hypercapnia but no prior history
of respiratory acidosis
• Adjust target range to 94-98% if the pCO2 is normal
68
what are the 4 indications for NIV AKA bipap
Non-invasive ventilation - key indications
• COPD with respiratory acidosis pH 7.25-7.35
• Type II respiratory failure secondary to chest wall deformity, neuromuscular disease or
obstructive sleep apnoea
• Cardiogenic pulmonary edema unresponsive to CPAP
• Weaning from tracheal intubation.
69
What are the Recommended initial settings for bi-level pressure support in COPD:
- EPAP
- IPAP
- Fi02
- back up rate
- back up inspiration:expiration ratio
- keep SP02 between?
• Expiratory Positive Airway Pressure (EPAP): 4-5 cm H2O
• Inspiratory Positive Airway Pressure (IPAP): RCP advocate 10 cm H20 whilst BTS suggest 12-
15 cm H2O
• FiO2: not > 40%
• Back up rate: 15 breaths/min
• Back up inspiration:expiration ratio: 1:3
• Keep SpO2: 88-92%
• ABG every 1-2 hours
70
Is V/Q scan for PE sensitive? specific?
| what are other causes of V/Q mismatch?
• Sensitivity = 98%; specificity = 40% - high negative predictive value, i.e. If normal virtually
excludes PE
• Other causes of mismatch in V/Q include:
o Old pulmonary embolisms
o AV malformations
o Vasculitis
o Previous radiotherapy
• COPD gives matched defects
71
What is a limitation of CTPA?
Peripheral emboli affecting subsegmental arteries may be missed
72
What should all asthma patients be investigated with?
patients should be asked if their symptoms are better on days away from work/during holidays. If so, patients should be referred to a specialist as possible occupational asthma
all patients should have spirometry with a bronchodilator reversibility (BDR) test
all patients should have a FeNO test
73
What are the causes for upper zone fibrosis?
```
C - Coal worker's pneumoconiosis
H - Histiocytosis/ hypersensitivity pneumonitis
A - Ankylosing spondylitis
R - Radiation
T - Tuberculosis
S - Silicosis/sarcoidosis
```
74
What are the causes of lower zone fibrosis?
idiopathic pulmonary fibrosis
most connective tissue disorders (except ankylosing spondylitis) e.g. SLE
drug-induced: amiodarone, bleomycin, methotrexate
asbestosis
75
What antibiotic is recommended for COPD patients?
azithromycin prophylaxis is recommended in select patients
other prerequisites include a CT thorax (to exclude bronchiectasis) and sputum culture (to exclude atypical infections and tuberculosis)
LFTs and an ECG to exclude QT prolongation should also be done as azithromycin can prolong the QT interval
76
How long should anticoag be continued for in patients with transient risk factors?
3 months
77
How long should anticoag be continued for in patients with permanent risk factors or idiopathic?
6 months
78
what are 5 organisms which cause CAP
* Streptococcus pneumoniae (accounts for around 80% of cases)
* Hemophilus influenzae
* Staphylococcal aureus
* Atypical pneumonias (e.g. due to Mycoplasma pneumoniae)
* Viruses
79
what can strep. pneumoniae cause? what is it assoc. with?
Streptococcus pneumoniae commonly causes reactivation of the herpes simplex virus resulting in 'cold sores and associated with foreign travel
80
Who does klebsiella pneumoniae affect classically? what cxr appearances may be seen? what is the mortality?
```
Klebsiella pneumoniae (Friedlander's pneumonia) is classically in alcoholics. CXR features may
include abscess formation in the middle/upper lobes and empyema. The mortality approaches 30-50%
```
81
what are 4 characteristic features of pneumococcal pneumonia
```
Characteristic features of pneumococcal pneumonia
• Rapid onset
• High fever
• Pleuritic chest pain
• Herpes labialis
```
82
what are different antibiotic choices for CAP
Antibiotic choices The British Thoracic Society published guidelines in 2009:
• Low or moderate severity CAP: oral amoxicillin. A macrolide should be added for patients
admited to hospital
• High severity CAP: intravenous co-amoxiclav + clarithromycin OR cefuroxime +
clarithromycin OR cefotaxime + clarithromycin
83
how do you assess severity of CAP?
| -what other factors are also assoc with poor prognosis?
CURB-65 criteria of severe pneumonia
• Confusion (abbreviated mental test score < 8/10)
• Urea > 7 mmol/L
• Respiratory rate = 30 / min
• BP: systolic < 90 or diastolic < 60 mmHg
• age > 65 years
Patients are stratified for risk of death as follows:
0: low risk (less than 1% mortality risk)
1 or 2: intermediate risk (1-10% mortality risk)
3 or 4: high risk (more than 10% mortality risk).
Other factors associated with a poor prognosis include:
• Presence of coexisting disease
• Hypoxemia (pO2 < 8 kPa) independent of FiO2
84
what bacterial organisms cause infectious exacerbation COPD?
| -what percentage of exacerbations are assoc. with viral illness? what is the no1 viral cause?
* Hemophilus influenzae (most common cause)
* Streptococcus pneumoniae
* Moraxella catarrhalis
Respiratory viruses account for around 30% of exacerbations, with the human rhinovirus being # 1.
85
what bacteria pneumonia affects young people in boarding houses/hostels
Mycoplasma pneumoniae is a cause of atypical pneumonia which often affects younger patients frequently amongst those living in boarding houses (housings, hostels).
86
describe the clinical features of Mycoplasma pneumoniae
- what symptoms are seen?
- what is seen on CXR
- what are 7 complications?
• Flu-like symptoms classically PRECEDE a dry cough
• Bilateral consolidation on x-ray
• Complications:
o Cold agglutins (IgM) may cause an hemolytic anemia, thrombocytopenia
o Erythema multiforme, erythema nodosum
o Meningoencephalitis, Guillain-Barre syndrome
o Bullous myringitis: painful vesicles on the tympanic membrane
o Pericarditis/myocarditis
o Gastrointestinal: hepatitis, pancreatitis
o Renal: acute glomerulonephritis
• Young Patient
• Signs & Symptoms of chest infection
• Hematuria
Mycoplasma Pneumonia
87
What is used in the diagnosis of mycoplasma pneumoniae?
• Mycoplasma serology
• Can be differentiated from other types of pneumonia by the relatively slow progression of
symptoms, a positive coombs in 50-70% after 10 days of infection (should be used with caution
or not at all since 50% of the tests are false-positive), lack of bacteria in a gram-stained sputum,
and a lack of growth on blood agar.
• PCR has also been used
88
what is the antibiotic management of mycoplasma pneumoniae?
* Erythromycin/clarithromycin
| * Tetracyclines such as doxycycline are an alternative
89
what terms are used for PCP?
whilst the organism Pneumocystis carinii is
now referred to as Pneumocystis jiroveci, the term Pneumocystis carinii pneumonia (PCP) is still in
common use
90
what type of organism is PCP?
- which patients does PCP affect?
- how is the risk of this reduced?
• Pneumocystis jiroveci is an unicellular eukaryote, generally classified as a fungus but some
authorities consider it a protozoa
• PCP is the most common opportunistic infection in AIDS
• All patients with a CD4 count < 200/mm3 should receive PCP prophylaxis
91
what are 4 features of PCP pneumonia?
```
Features
• Dyspnea
• Dry cough
• Fever
• Very few chest signs
```
92
what are 3 extrapulmonary manifestations of PCP?
| -are these common or rare?
Extrapulmonary manifestations are rare (1-2% of cases), may cause
• Hepatosplenomegaly
• Lymphadenopathy
• Choroid lesions
93
what investigations are used in diagnosis of
| PCP?
• CXR: typically shows bilateral interstitial pulmonary infiltrates but can present with other x-ray
findings e.g. lobar consolidation. May be normal
• Exercise-induced desaturation
• Sputum often fails to show PCP, bronchoalveolar lavage (BAL) often needed to demonstrate
PCP (silver stain)
94
what is included in the management of PCP?
• Co-trimoxazole
• IV pentamidine in severe cases
• Steroids if hypoxic (if pO2 < 9.3kPa (9.3*7.5=71mmHg) then steroids ↓ risk of respiratory
failure by 50% and death by a third)
95
what kind of bacteria in legionella pneumonphilia? where does this usually colonise?
Legionnaire's disease is caused by the intracellular bacterium Legionella pneumophilia (Gram –ve bacilli). It is typically colonizes water tanks (hint → air-
conditioning systems, showers or foreign holidays) Person-to-person transmission is not seen
96
what are 7 features of legionnaires?
```
Features
• Flu-like symptoms
• 50% of cases have GI symptoms such as nausea, vomiting, diahrrhea and abdominal pain.
• Dry cough
• Lymphopenia
• Hyponatremia
• Deranged LFTs
• Hematuria occurs and occasionally renal failure.
```
Legionella is suggested if 3 of the following 4
features are present:
• Prodormal viral like illness
• Dry cough, confusion or diarrhea
• Lymphopenia without marked leukocytosis.
• Hyponatremia
97
what is the diagnosis of legionnaires?
Diagnosis
| • Urinary antigen
98
what is the treatment of legionnaires?
Management
| • Treat with erythromycin
99
what is extrinsic allergic alveolitis?
is a condition caused by hypersensitivity induced lung damage due to a variety of inhaled organic particles. It is thought to be largely caused by immune-
complex mediated tissue damage (type III hypersensitivity = acute phase) although delayed
hypersensitivity (type IV = chronic phase) is also thought to play a role in EAA, especially in the
chronic phase
100
what do avians proteins cause?
EAA - Bird fanciers' lung
101
what do spores of micropolyspora faeni cause?
EAA -
| spores of Saccharopolyspora rectivirgula (formerly Micropolyspora faeni)
102
what does aspergillus clavatus cause?
EAA - Malt workers' lung
103
what does thermophilic actinomycetes cause?
EAA - Mushroom workers' lung
104
what is the presentation of extrinsic allergic alveolitis?
Presentation
• Acute: occur 4-8 hrs after exposure, SOB, dry cough, fever
• Chronic
105
What do investigations show in EAA?
- CXR
- BAL
- blood
* CXR: upper lobe fibrosis
* BAL (bronchoalveolar lavage): lymphocytosis
* Blood: NO eosinophilia
* Circulating IgG precipitant
NOT ALLERGY:
• No eosinophilia
• No ↑ IgE
• No positive skin prick
106
What are 7 causes of upper lobe fibrosis?
```
Fibrosis predominately affecting the UPPER ZONES
• Extrinsic allergic alveolitis
• Coal worker's pneumoconiosis/progressive massive fibrosis
• Silicosis
• Sarcoidosis
• Ankylosing spondylitis (rare)
• Histiocytosis
• Tuberculosis
```
107
what are 4 causes of lower lobe fibrosis?
Fibrosis predominately affecting the LOWER ZONES
• Cryptogenic fibrosing alveolitis
• Most connective tissue disorders (except ankylosing spondylitis)
• Drug-induced: amiodarone, bleomycin, methotrexate
• Asbestosis
108
is the severity of asbestosis related to length of exposure?
the severity of asbestosis is related to the length of exposure.
109
what is the latent period of asbestosis?
The latent period is typically 15-30 years.
110
does asbestosis cause upper or lower lobe fibrosis?
Asbestosis typically causes lower lobe fibrosis.
111
what is the most dangerous form of asbestos?
Crocidolite (blue) asbestos As with other forms of lung fibrosis the most
112
what is the common features of absestos? what other features can also be seen?
-when are pleural plaques seen?
As with other forms of lung fibrosis the most
common symptoms are shortness-of-breath and reduced exercise tolerance.
Possible features
• Progressive SOB
• Chest pain
• Pleural effusion
* Pleural thickening in a similar pattern to that seen following an empyema or hemothorax. The underlying pathophysiology is not fully understood.
* Pleural plaques also seen (not premalignant). They are the most common form of asbestos related lung disease and generally occur after a latent period of 20-40 years.
113
what is the treatment for asbestosis?
Patients are usually offered palliative chemotherapy and there is also a limited role for surgery and radiotherapy.
Unfortunately the prognosis is very poor, with a median survival from diagnosis of 8-14 months.
114
What is asbestos a risk factor for?
| -what does this have a synergistic effect with?
Asbestos exposure is a risk factor for lung cancer and also has a synergistic effect with cigarette smoke
(this is true for lung ca not for mesothelioma).
115
What is the difference between primary and secondary pneumothora?
-if the patient is asthmatic should this be treated as primary or secondary?
A pneumothorax
is termed primary if there is no underlying lung
disease and secondary if there is.
If patient is asthmatic → treat as secondary pneumothorax
116
When can patients air travel after pneumothorax?
Pt cannot air-travel for 2 weeks post complete aspiration of the air.
117
How is primary pneumothorax managed?
* If the rim of air is < 2cm and the patient is not short of breath then discharge should be considered
* Otherwise aspiration should be attempted
* If this fails then repeat aspiration should be considered
* If this fails then a chest drain should be inserted
118
How is secondary pneumothorax treated?
* If the patient is > 50 years old and the rim of air is >2cm and the patient is short of breath then a chest drain should be inserted.
* Otherwise aspiration should be attempted. If aspiration fails a chest drain should be inserted. All patients should be admitted for at least 24 hours
119
for iatrogenic pneumothorax
- is this likely to recur
- what is the treatment
- who may need chest drains?
* Less likelihood of recurrence than spontaneous pneumothorax
* Majority will resolve with observation, if treatment is required then aspiration should be used
* Ventilated patients need chest drains, as may some patients with COPD
120
how much does smoking increase the risk of lung Ca?
Smoking
• ↑ risk of lung ca by a factor of 10
Whilst many chemicals have been implicated in the development of lung cancer passive smoking is the most likely cause. Up to 15% of lung cancers in patients who do not smoke are thought to be caused by passive smoking
121
what are 7 other factors assoc. with lung ca apart from smoking?
```
Other factors
• Asbestos - ↑ risk of lung ca by a factor of 5
• Arsenic
• Radon
• Nickel
• Chromate
• Aromatic hydrocarbon
• Cryptogenic fibrosing alveolitis
```
122
What indicates an immediate referral for patients with suspected lung Ca?
Consider immediate referral for patients with:
• Signs of superior vena caval obstruction (swelling of the face/neck with fixed elevation of
jugular venous pressure)
• Stridor
123
what indicates an urgent referral for patients with suspected lung ca?
• Persistent hemoptysis (in smokers or ex-smokers aged 40 years and older)
• A chest x-ray suggestive of lung cancer (including pleural effusion and slowly resolving
consolidation)
• A normal chest x-ray where there is a high suspicion of lung cancer
• A history of asbestos exposure and recent onset of chest pain, shortness of breath or
unexplained systemic symptoms where a chest x-ray indicates pleural effusion, pleural mass or
any suspicious lung pathology
124
when should patients be referred urgently for chest xray when considering lung ca?
Refer urgently for chest x-ray for patients with any of the following:
• Hemoptysis
• Unexplained or persistent (longer than 3 weeks): chest and/or shoulder pain, dyspnea, weight
loss, chest signs, hoarseness, finger clubbing, cervical or supraclavicular lymphadenopathy,
cough, features suggestive of metastasis from a lung cancer (for example, secondaries in the
brain, bone, liver, skin)
• Underlying chronic respiratory problems with unexplained changes in existing symptoms
125
what are the 5 types of lung ca?
- which is most common in the uk?
- which is most common in the US?
* Squamous: 35%
* Adenocarcinoma: 30%
* Small (oat) cell: 15%
* Large cell: 10%
* Other: 5%
Squamous is the most common in UK, Adenocarcinoma is the most common in US
Other tumours
• Alveolar cell carcinoma: not related to smoking, ++sputum
• Bronchial adenoma: mostly carcinoid
126
describe the paraneoplastic features of lung ca
- squamous cell
- small cell
Paraneoplastic features of lung cancer
• Squamous cell: PTHrp, clubbing, HPOA
• Small cell: ADH, ACTH, Lambert-Eaton syndrome
127
what are the features of small cell lung ca?
- anatomically
- paraneoplastic syndrome
```
• Usually central
• Arise from APUD* cells
• ADH → Hyponatremia
• ACTH → cushing's syndrome
• ACTH secretion can cause bilateral adrenal hyperplasia, the high levels of cortisol can lead to
hypokalaemic alkalosis
• Lambert-eaton syndrome: antibodies to voltage gated calcium channels causing myasthenic like
syndrome
```
*an acronym for
• Amine - high amine content
• Precursor Uptake - high uptake of amine precursors
• Decarboxylase - high content of the enzyme decarboxylase
128
describe different management options for small cell lung ca?
Management
• Usually metastatic disease by time of diagnosis
• Surgery: only used for debulking
• Radiotherapy: only used for debulking
• Chemotherapy (being the mainstay of treatment): good response to combination chemotherapy,
may extend life by approximately 4 months
129
what are 4 contraindications to lung ca surgery?
Contraindications to lung cancer surgery include SVC obstruction, FEV < 1.5, MALIGNANT pleural effusion, and vocal cord paralysis
130
what are the three main subtypes of non-small cell lung ca?
squamous cell lung ca
adenocarcinoma
large cell lung ca
131
squamous cell lung ca
- anatomical distribution
- which blood test will be raised and why
- what clinical feature is it strongly assoc with
- what bone feature is assoc
* Typically central
* Associated with ectopic PTH secretion HYPERCALCAEMIA
* Strongly associated with finger clubbing
* Hypertrophic pulmonary osteoarthropathy (HPOA)
132
adenocarcinoma
- smokers or non-smokers?
- anatomical distribution
• Most common type of lung cancer in non-smokers, although the majority of patients who
develop lung adenocarcinoma are smokers
• Typically located on the lung periphery
133
describe the management of non-small cell lung ca
* Only 20% suitable for surgery
* Mediastinoscopy prior to surgery as CT does not always show mediastinal node involvement
* Curative or palliative radiotherapy
* Poor response to chemotherapy
134
describe surgical contraindications for lung ca
* Assess general health
* Stage IIIb or IV (i.e. Metastases present)
* FEV1 < 1.5 litres is considered a general cut-off point*
* Malignant pleural effusion
* Tumour near hilum or within 2 cm of bronchus
* Vocal cord paralysis
* SVC obstruction
* However if FEV1 < 1.5 for lobectomy or < 2.0 for pneumonectomy then some authorities advocate
further lung function tests as operations may still go ahead based on the results
135
what are the paraneoplastic features of small cell lung ca
```
• ADH
• ACTH - not typical, hypertension,
hyperglycemia, Hypokalemia, alkalosis
and muscle weakness are more common
than buffalo hump etc
• Lambert-Eaton syndrome
```
136
what are the paraneoplastic features of squamous cell lung ca
```
• PTH-rP
• Clubbing
• Hypertrophic pulmonary osteoarthropathy
(HPOA)
• Hyperthyroidism due to ectopic TSH
```
137
what is the paraneoplastic feature of adenocarcinoma
• Gynaecomastia
138
Bronchial carcinoma:
- what type?
- what cells does this arise from?
- what is the tumour appearance?
20-30% of cases with bronchial carcinoma are of the small (oat) cell
type and arise from endocrine (Kulchitsky) cells.
Primary Bronchial Cancer, the tumor edge may have a fluffy or spiked appearance
139
what are the paraneoplastic features of bronchial carcinoma?
* Syndrome of inappropriate ADH secretion (SIADH) 5-10%
* Ectopic secretion of ACTH 5%
* Ectopic atrial natriuretic peptide (ANP) secretion can also occur
140
what 8 respiratory problems are seen in patients with rheumatoid arthritis?
* Pulmonary fibrosis
* Pleural effusion
* Pulmonary nodules
* Bronchiolitis obliterans
* Complications of drug therapy e.g. Methotrexate pneumonitis
* Pleurisy
* Caplan's syndrome - massive fibrotic nodules with occupational coal dust exposure
* Infection (possibly atypical) secondary to immunosuppression
141
what does lung cavitations on CXR make you think of (8)
* Tuberculosis
* Lung cancer (especially squamous cell)
* Abscess (staph aureus, klebsiella and Pseudomonas)
* Wegener's granulomatosis
* Pulmonary embolism
* Rheumatoid arthritis
* Aspergillosis, histoplasmosis, coccidioidomycosis
142
what is sarcoidosis?
| -how much will remit without treatment
is a multisystem disorder of unknown aetiology characterized by non-caseating
granulomas. It is more common in young adults and in people of African descent. Sarcoidosis remits
without treatment in approximately two-thirds of people.
143
What are the stages of sarcoidosis?
* 0 = normal
* 1 = BHL
* 2 = BHL + infiltrates
* 3 = infiltrates
* 4 = fibrosis
144
what routine blood tests are used in sarcoid?
| -what blood test may be used in monitoring of disease?
There is no one diagnostic test for sarcoidosis and hence diagnosis is still largely clinical. ACE levels
have a sensitivity of 60% and specificity of 70% and are therefore not reliable in the diagnosis of
sarcoidosis although they may have a role in monitoring disease activity. Routine bloods may show
hypercalcemia (seen in 10% if patients) and a raised ESR
145
What investigations can be used for sarcoid apart from blood tests
Other investigations*
• Spirometry: may show a restrictive defect
• Tissue biopsy: non-caseating granulomas
• Gallium-67 scan - not used routinely
*the Kveim test (where part of the spleen from a patient with known sarcoidosis is injected under the
skin) is no longer performed due to concerns about cross-infection
146
what factors in sarcoid are assoc with a poor prognosis?
```
Factors associated with poor prognosis
• Insidious onset, symptoms > 6 months
• Absence of erythema nodosum
• Extrapulmonary manifestations: e.g. Lupus pernio, splenomegaly
• CXR: stage III-IV features
• Black people
```
147
what is Mikulicz syndrome?
Mikulicz syndrome: is a chronic condition characterized by the abnormal enlargement of parotids,
lacrimal and salivary glands. The tonsils and other glands in the soft tissue of the face and neck may
also be involved. It is associated with sarcoidosis
148
what are the indications for steroids in sarcoidosis?
```
Indications for steroids
• Hypercalcemia
• Worsening lung function
• Eye (bilateral posterior uveitis is common eye manifestation)
• Heart or neuro involvement
```
149
what are the causes for BHL/bulky mediastinum?
```
Causes include:
• Sarcoidosis
• Tuberculosis
• Lymphoma/other malignancy
• Pneumoconiosis e.g. Berylliosis
• Fungi e.g. Histoplasmosis, coccidioidomycosis (VHL + Cavitation in CXR)
```
most common in TB and sarcoid
150
what is Lofgren's syndrome?
is an acute form sarcoidosis characterized by bilateral hilar lymphadenopathy (BHL), erythema nodosum, fever and polyarthralgia. It typically occurs in young ♀s
and carries an excellent prognosis
151
features of lofgren's syndrome
- CXR
- bloods
- caused by
- presenting features
- treatment
* Transient CXR shadowing and blood eosinophilia
* Thought to be due to parasites such as Ascaris lumbricoides causing an alveolar reaction
* Presents with a fever, cough and night sweats which often last for less than 2 weeks.
* Generally a self-limiting disease
152
10 causes of pulmonary eosinophilia
• Churg-Strauss syndrome (eosinophilia + asthma
+ hemorrhage)
• Allergic bronchopulmonary aspergillosis
(ABPA)
• Loffler's syndrome
• Eosinophilic pneumonia
* Hypereosinophilic syndrome
* Tropical pulmonary eosinophilia
* Drugs: nitrofurantoin, sulphonamides
* Less common: Wegener's granulomatosis
* Tropical pulmonary eosinophilia
* Associated with Wuchereria bancrofti infection
153
what does silicosis increase the risk for?
| -what are the features/
Silicosis is a risk factor for developing TB (silica is toxic to macrophages)
Features
• Fibrosing lung disease
• 'Egg-shell' calcification of hilar lymph nodes
154
what is bronchiectasis?
describes a permanent dilatation of the airways secondary to chronic infection or
inflammation.
155
what is the symptom control in non-CF bronchiectasis?
Symptom control in non-CF bronchiectasis - inspiratory muscle training + postural drainage
156
what are the causes of bronchiectasis?
* Post-infective: tuberculosis, measles, pertussis, pneumonia
* Cystic fibrosis
* Bronchial obstruction e.g. Lung cancer/foreign body
* Immune deficiency: selective IgA, hypogammaglobulinemia
* Allergic bronchopulmonary aspergillosis (ABPA)
* Ciliary dyskinetic syndromes: kartagener's syndrome, young's syndrome
* Yellow nail syndrome (associated with pleural effusion - exudates)
157
what is the management of bronchiectasis?
After assessing for treatable causes (e.g. immune deficiency) MANAGEMENT is as follows:
• Physical training (e.g. Inspiratory muscle training) - has a good evidence base for patients with
non-cystic fibrosis bronchiectasis
• Postural drainage
• IV antibiotics for exacerbations + long-term rotating antibiotics (nebulized ABX) in severe
cases
• Bronchodilators in selected cases
• Immunisations
• Surgery in selected cases (e.g. Localised disease)
158
what is the management for Pseudomonas aeruginosa:
* Insensitive for Amoxicillin
* IV Ticarcillin + IV Gentamycin
* IV Colistin for resistant cases
159
what are the four most common organisms isolated from patients with bronchiectasis
* Hemophilus influenzae (most common)
* Pseudomonas aeruginosa
* Klebsiella spp.
* Streptococcus pneumoniae
160
what are the predispositions for sleep apnoea
* Obesity
* Macroglossia: acromegaly, hypothyroidism, amyloidosis
* Large tonsils
* Marfan's syndrome
161
what can sleep apnoea cause
* Daytime somnolence
| * Hypertension
162
what is used in the diagnosis of sleep apnoea
Assessment of sleepiness
• Epworth Sleepiness Scale - questionnaire completed by patient +/- partner
• Multiple Sleep Latency Test (MSLT) - measures the time to fall asleep in a dark room (using
EEG criteria)
Diagnostic tests
• Sleep studies - ranging from monitoring of pulse oximetry at night to full polysomnography
where a wide variety of physiological factors are measured including EEG, respiratory airflow,
thoraco-abdominal movement, snoring and pulse oximetry
163
What is the management of sleep apnoea?
• Weight loss
• CPAP is first line for moderate or severe OSAHS
• Intra-oral devices (e.g. Mandibular advancement) may be used if CPAP is not tolerated or for
patients with mild OSAHS where there is no daytime sleepiness
• Limited evidence to support use of pharmacological agents
164
what is the criteria for ARDS?
* Acute onset
* Bilateral infiltrates on CXR
* Non-cardiogenic (pulmonary artery wedge pressure needed if doubt)
* pO2/FiO2 < 200 mmHg
165
what is allergic bronchopulmonary aspergillosis?
Allergic bronchopulmonary aspergillosis (ABPA) results from an allergy to
Aspergillus spores. In the exam questions often give a history of bronchiectasis and eosinophilia.
166
what are the features of allergic bronchopulmonary aspergillosis?
Features
• Bronchoconstriction: wheeze, cough, dyspnea
• Bronchiectasis (proximal)
167
what are the investigations for allergic bronchopulmonary aspergillosis?
* Eosinophilia
* Flitting CXR changes
* Positive radioallergosorbent (RAST) test to aspergillus
* Positive IgG precipitins (not as positive as in aspergilloma)
* Raised IgE
168
what is included in the management of allergic bronchopulmonary aspergillosis?
* Steroids (think.. allergy to aspergillus)
| * Itraconazole is sometimes introduced as a second line agent
169
what is aspergilloma?
Aspergilloma is a fungus ball which often colonises an existing lung cavity (e.g. secondary to TB,
lung cancer or cystic fibrosis)
170
what are the clinical features of aspergilloma?
Usually asymptomatic but features may include
• Cough
• Hemoptysis (may be severe)
171
what investigations are used in aspergilloma?
Investigations
• CXR containing a rounded opacity
• High titres Aspergillus precipitins
172
What is cystic fibrosis?
- how is it inherited?
- wat is it due to?
- what are the cytogenetics?
- how common is this?
Cystic fibrosis (CF) is an autosomal
recessive disorder causing ↑ viscosity of
secretions (e.g. lungs and pancreas). It is due
to a defect in the cystic fibrosis
transmembrane conductance regulator gene
(CFTR), which codes a cAMP-regulated
chloride channel. The most common
inherited lethal condition in Caucasians
In the UK 80% of CF cases are due to a
deletion at delta F508 on the long arm of
chromosome 7. Cystic fibrosis affects 1 per
2500 births, and the carrier rate is c. 1 in 25
173
what 4 organisms may colonise CF patients?
```
Organisms which may colonise CF patients
• Staph aureus
• Pseudomonas aeruginosa (Rx: Inhaled Tobramycin)
• Burkholderia cepacia*
• Aspergillus
```
174
what is cepacia syndrome in CF?
Cepacia Syndrome in CF: characterized by a rapidly progressive fever, uncontrolled
bronchopneumonia, septicemia, weight loss, and poor outcomes.
175
what is the management of cepacia syndrome?
Management:
• Aminoglycosides + Ceftazidime
• Ceftazidime + Cholramphenicol
• Cholramphenicol + Minocycline
176
what are the presenting features of CF?
| -name some other features?
Presenting features
• Neonatal period (around 20%): meconium ileus, less commonly prolonged jaundice
• Recurrent chest infections (40%)
• GI Manifestation: malabsorption (30%) steatorrhoea, liver disease, cholesterol gall stones,
peptic ulcers, ↑ GI malignancy.
• Other features: failure to thrive
```
Other features of cystic fibrosis
• Short stature
• Diabetes Mellitus
• Delayed puberty
• Rectal prolapse (due to bulky stools)
• Nasal polyps
• ♂ infertility, ♀ subfertility
```
177
What is the diagnosis of CF?
Diagnosis:
| • Sweat test: 2 reliable positive results on 2 separate days is diagnostic for CF. it is positive when chloride is > 60
178
what is the management of CF?
Management of cystic fibrosis involves a multidisciplinary approach. Key points:
• Regular (at least twice daily) chest physiotherapy and postural drainage. Parents are usually
taught to do this. Deep breathing exercises are also useful
• High calorie diet, including high fat intake*
• Vitamin supplementation
• Pancreatic enzyme supplements taken with meals
• Heart and lung transplant
179
What is bronchiolitis obliterans?
is the term used to describe fibrous scarring of the small airways. It is seen following: toxic-fume inhalation; mineral-dust exposure; viral infection; mycoplasma and legionella infection; bone marrow, heart–lung and lung transplantation; rheumatoid arthritis; SLE; and as a side-effect of penicillamine
180
what are the clinical features of bronchiolitis obliterans?
It presents as a dry cough and dyspnea. Physical examination is unremarkable. Expiratory wheeze may be audible.
181
what are the chest x ray findings in bronchilolitis obliterans?
- how to confirm diagnosis?
- response to steroids?
- prognosis?
The chest X-ray findings can vary from normal to a reticular or reticulonodular pattern. The diagnosis can be confirmed by lung biopsy. Patients rarely respond to steroids. The prognosis is poor
182
what are the 7 causes of an exudate pleural effusion?
Exudate - (> 30g/L protein)
• Infection: pneumonia, TB, subphrenic abscess
• Connective tissue disease: RA ( glucose < 1.6, LDH > 700, pH < 7.2,↑ R.F > 1:320, ↑ cholesterol), SLE
• Neoplasia: lung cancer, mesothelioma, metastases
• Pancreatitis
• Pulmonary embolism
• Dressler's syndrome
• Yellow nail syndrome (also known as "Primary lymphedema associated with yellow dystrophic nails
and pleural effusion. Approximately 40% will also have bronchiectasis. It is also associated with chronic sinusitis and persistent coughing. It usually affects adults and it’s very rare)
183
what are the 4 causes of a transudate pleural effusion?
Transudate - (< 30g/L protein)
• Heart failure
• Hypoalbuminemia (liver disease, nephrotic syndrome, malabsorption)
• Hypothyroidism
• Meigs' syndrome: triad of ascites, pleural effusion (right side) and benign ovarian tumor
(fibroma). It resolves after the resection of the tumor. For reasons unknown.
184
what are the indications for chest drain insertion in a pleural effusion?
Indications for chest tube insertion in patients with infected pleural effusions are: presence of organisms on a Gram stain of the pleural fluid, a frankly purulent pleural fluid, pleural pH < 7.2 in the setting of an infected pleural effusion, loculated pleural effusions and poor clinical progress despite antibiotic treatment.
185
what causes transfusion related acute lung injury?
Transfusion Related Acute Lung Injury (TRALI): caused by anti-HLA, Human Neutrophil Antigens (HNA) or antigranulocytes antibody in donor blood.
186
who is at high risk of TRALI?
Donor’s blood sensitization occurs in:
• Multiparous ♀ develop these antibodies through exposure to fetal blood
• Previous transfusion
• Transplantation patient
When blood is obtained from above mentioned donors, it carries higher risk for recipient to develop TRALI; those who have lung pathology are more susceptible. TRALI symptoms resemble ARDS.
187
what is the diagnosis of TRALI?
Diagnosis: confirmed by finding of anti-HLA or anti-Neutrophil antibody in donors’ or recipient blood.
188
What is alpha 1 antitrypsin caused by? what is the role of A1AT in the lung?
Alpha-1 antitrypsin (A1AT) deficiency is a common inherited condition caused by a lack of a protease inhibitor (Pi) normally produced by the liver. The role of A1AT is to protect cells from enzymes such as neutrophil elastase. It classically causes emphysema (i.e. chronic obstructive pulmonary disease) in patients who are young and non-smokers.
189
Which chromosome is the A1AT gene located?
- how is this inherited?
- how are allelles classified and how does this affect amounts of A1AT?
```
located on chromosome 14
inherited in an autosomal recessive / co-dominant fashion*
alleles classified by their electrophoretic mobility - M for normal, S for slow, and Z for very slow
normal = PiMM
homozygous PiSS (50% normal A1AT levels)
homozygous PiZZ (10% normal A1AT levels)
```
190
What are the features of A1AT?
- which genotype will patients most likely have who will manifest disease?
- what is seen in the lungs?
- what is seen in the liver?
patients who manifest disease usually have PiZZ genotype
lungs: panacinar emphysema, most marked in lower lobes
liver: cirrhosis and hepatocellular carcinoma in adults, cholestasis in children
191
What are the investigations for A1AT?
A1AT concentrations
| spirometry: obstructive picture
192
What is the management for A1AT?
no smoking
supportive: bronchodilators, physiotherapy
intravenous alpha1-antitrypsin protein concentrates
surgery: lung volume reduction surgery, lung transplantation
193
What are the three main types of altitude sickness?
There are three main types of altitude related disorders: acute mountain sickness (AMS), which may progress to high altitude pulmonary edema (HAPE) or high altitude cerebral edema (HACE). All three conditions are due to the chronic hypobaric hypoxia which develops at high altitudes
194
AMS
- when do features start to occur?
- how long do symptoms develop?
- how long can symptoms last?
- what are the three most common symptoms?
Acute mountain sickness is generally a self-limiting condition. Features of AMS start to occur above 2,500 - 3,000m, developing gradually over 6-12 hours and potentially last a number of days:
headache
nausea
fatigue
195
How can AMS be prevented?
Prevention and treatment of AMS
the risk of AMS may actually be positively correlated to physical fitness
gain altitude at no more than 500 m per day
acetazolamide (a carbonic anhydrase inhibitor) is widely used to prevent AMS and has a supporting evidence base
treatment: descent
196
What two conditions can AMS develop into and at what altitude?
A minority of people above 4,000m go onto develop high altitude pulmonary oedema (HAPE) or high altitude cerebral oedema (HACE), potentially fatal conditions
HAPE presents with classical pulmonary oedema features
HACE presents with headache, ataxia, papilloedema
197
What is involved in the management of HACE?
Management of HACE
descent
dexamethasone
198
What is involved in the management of HAPE?
Management of HAPE
descent
nifedipine, dexamethasone, acetazolamide, phosphodiesterase type V inhibitors*
oxygen if available
*the relative merits of these different treatments has only been studied in small trials. All seem to work by reducing systolic pulmonary artery pressure
199
what is cryptogenic organising pneumonia?
Cryptogenic organizing pneumonia (COP) is a diffuse interstitial lung disease that affects the distal bronchioles, respiratory bronchioles, alveolar ducts and alveolar walls. It affects around 2 people per 100,000. The aetiology is unknown.
200
what are the presenting features of cryptogenic organising pneumonia?
Males and females are equally affected and tend to present in the 5th or 6th decade of life and is not associated with smoking. Patients typically present with a cough, shortness of breath, fever and malaise. Symptoms can be present for weeks or months. There is often a history of non-response to antibiotics. Haemoptysis is rare. Clinical examination is often normal but inspiratory crackles can be heard. Wheeze and clubbing are rare.
201
what is kartageners syndrome
Kartagener's syndrome (also known as primary ciliary dyskinesia) was first described in 1933 and most frequently occurs in examinations due to its association with dextrocardia (e.g. 'quiet heart sounds', 'small volume complexes in lateral leads')
202
What are the features of kartageners syndromes?
Features
• Dextrocardia or complete situs inversus
• Bronchiectasis
• Recurrent sinusitis
• Subfertility (secondary to diminished sperm motility and defective ciliary action in the fallopian tubes)
203
which two conditions prevent going on an aeroplane? how long do you have to wait?
Respiratory disease
• Pneumonia: should be 'clinically improved with no residual infection'
• Pneumothorax: absolute contraindication, may travel 2 weeks after successful drainage if there
is no residual air
204
what are respiratory causes of clubbing?
```
• Lung cancer
• Pyogenic conditions: cystic fibrosis,
bronchiectasis, abscess, empyema
• Asbestosis, mesothelioma
• Fibrosing alveolitis
```
