Respiratory Flashcards
define asthma ?
- chronic inflammatory airway disease leading to variable airway obstruction
- bronchoconstriction is reversible with bronchodilators
name 3 respiratory emergencies
anaphylaxis
pneumothorax
pulmonary embolism
define ventilation
movement of air into and out of lungs during a single breathing cycle
what is alveolar ventilation and how do you calculate it?
total volume of air that reaches the alveoli and contributes to gas exchange
alveolar ventilation = RR x (tidal volume - dead space volume)
why is the concept of physiological dead space important?
physiological dead space = volume of lung that doesn’t eliminate CO2
- important because if this space increases (e.g. pneumonia) then patient needs to increase minute ventilation to maintain adequate gas exchange
what is hypoxic pulmonary vasoconstriction?
physiological response to alveolar hypoxia
- if PA02 decreases, pulmonary arterioles vasoconstrict to limit blood flow to hypoxic alveoli
what is the V/Q ration if ventilation is 4L/min and perfusion is 5L/min ?
4/5 or 0.8
what happens to V/Q ration if you decrease ventilation or perfusion?
decreased ventilation? V/Q ration decreases
increased ventilation? V/Q ratio increases
NB both V&Q are greater at the lung bases than apices
spirometry: what is FEV1?
Forced expiratory volume in 1 second (FEV1) = air a person can forcefully exhale in 1 second.
Measures how easily air can flow out of the lungs.
Reduced with airflow obstruction.
spirometry: what is FVC?
forced vital capacity = total air a person can exhale after a full inhalation
Measures volume of air someone can take into their lungs
Reduced with restricted lung capacity
when can we diagnose obstructive lung disease on spirometry?
Diagnosed when the FEV1 is less than 70% of the FVC = FEV1:FVC ratio of less than 70%
someone may have good lung volume but air can only move slowly in or out of lungs
causes of obstructive lung disease?
- asthma
- COPD
- bronchiectasis
- A1AT
- CF
when can we diagnose restrictive lung disease on spirometry?
- FEV1 and FVC are equally reduced
- FEV1:FVC ratio greater than 70%
lungs have limited ability to expand and fill with air
causes of restrictive lung disease?
fibrosis
sarcoidosis
obesity
MND
asthma risk factors?
- atopy (or FHx of atopy)
name 5 common asthma triggers?
Infection
Nighttime or early morning
Exercise
Animals
Cold, damp or dusty air
Strong emotions
name two medication classes that can worsen asthma symptoms?
- Beta-blockers, particularly non-selective beta-blockers (e.g., propranolol)
- NSAIDs (e.g., ibuprofen or naproxen)
what type o wheeze do you hear in asthma?
widespread “polyphonic” expiratory wheeze
asthma Px?
- episodic sx
- diurnal variation - worse at night
- SOB
- chest tightness
- dry cough
- wheeze - widespread, polyphonic
- reduced PEFR
asthma Ix?
NICE recommend:
1. Fractional exhaled nitric oxide (FeNO)
2. Spirometry with bronchodilator reversibility
Others to add in:
3. peak flow diary
4. direct bronchial challenge - opposite of reversibility testing
what % increase of FEV1 on reversibility testing suggests asthma?
greater than 12% increase in FEV1
BTS asthma management?
- SABA - salbutamol
- Add ICS - low dose beclometasone
- Add LABA - salmeterol / maintenance and reliever therapy (MART)
- Increase ICS dose / add leukotriene receptor antagonist (LTRA) - montelukast
- Specialist mx - eg oral prednisolone
NICE asthma management?
- SABA - salbutamol
- Add ICS - low dose beclometasone
- Add LTRA - montelukast
- Add LABA - salmeterol
- Consider changing to MART
- Increase ICS dose
- Consider high dose ICS or additional drugs - LAMA / theophylline
- Specialist mx - eg oral prednisolone
what other things are involved with asthma management other than asthma medication?
- ?occupational - refer to resp
- yearly flu jab
- yearly asthma review
- consider stepping down tx every 3mo or so
- reducing ICS dose - only by 25-30% at a time
- regular exercise, avoid smoking, avoid triggers
what medications make up MART and Trimbow?
MART - Fostair - beclometasone (ICS) + formoterol (LABA)
Trimbow - beclometasone + formoterol + glycopyrronium
example of a SABA?
salbutamol, terbutaline
name a LABA?
salmeterol, formoterol
name a SAMA?
ipratropium
Name a LAMA?
tiotropium
name some ICS used in asthma ?
beclometasone / budesonide / fluticasone
what is an acute exacerbation of asthma?
- rapid deterioration in sx in asthma
- triggers as chronic, may be infection
how might acute asthma present?
- SOB
- Cough
- Accessory muscle use
- Tachypnoea
- Global wheeze
- Reduced air entry
acute asthma grading criteria: moderate versus severe?
Moderate
- PEF 50-75%
Acute severe
- PEF 33-50% best
- RR>25
- HR>110
- Unable to complete sentences
acute asthma severity: life threatening
- PEF <33%
- Sats <92%
- Silent chest, cyanosis
- Bradycardia, low BP
- Exhaustion, confusion, coma
near fatal = raised pCO2
acute asthma Ix?
- ABG - resp alkalosis -> hypoxic -> normal pCO2
- bloods,
- CXR
when to admit with acute asthma?
- Life-threatening grade
- Acute severe grade + unresponsive to tx
- Previous near-fatal attack
- Pregnancy
- Occurring despite oral corticosteroid
- Px at night
acute asthma Mx?
Oxygen
Salbutamol - inhaler / nebs
Hydrocortisone - 100mg IV or prednisolone 40mg oral
Ipratropium - nebulised
Aminophylline - IV
Magnesium - IV
Escalate care
criteria for acute asthma discharge?
- Stable on discharge medication (no nebs / O2) for 12-24hrs
- Inhaler technique checked + recorded
- PEF >75%
why monitor serum potassium on salbutamol nebs?
salbutamol causes K+ to be absorbed from blood into cells leading to hypokalaemia
what is COPD?
- Chronic irreversible progressive condition involving airway obstruction, emphysema, chronic bronchitis
Related to:
- smoking
- A1AT deficiency
COPD: what is bronchitis and what is emphysema?
Bronchitis = long-term symptoms of a cough and sputum production due to inflammation in the bronchi
Emphysema = damage and dilatation of the alveolar sacs and alveoli, decreasing the surface area for gas exchange
how might COPD present?
long-term smoker with persistent symptoms of:
- Shortness of breath
- Cough
- Sputum production
- Wheeze
- Recurrent respiratory infections, particularly in winter
NB COPD does NOT cause clubbing!v
MRC SOB scale?
- SOB on marked exertion
- SOB on hills
- Slow or stop on flat
- Exercise tolerance 100-200 yards on flat
- Housebound / SOB on minor tasks
COPD versus asthma?
- Younger onset in asthma
- Smoking - in most with COPD
- Asthma - sx vary, less so in COPD
- Nocturnal sx in asthma
- Persistent productive cough - COPD
COPD Ix for diagnosis ?
- clinical
- spirometry - FEV1/FVC<70% with little/no response to reversibility testing
additional Ix you could do for COPD aside from spirometry?
- CXR - hyperinflation, flat hemidiaphragms, bullae
- FBC - anaemia/polycythaemia (raised Hb due to chronic hypoxia)
- ECG / ECHO - look for HF
- CT thorax - malignancy, bronchiectasis
- transfer factor for CO (TLCO)
- ?A1AT levels
how can we grade COPD severity - 4 stage scale
Using FEV1;
Stage 1 / mild - FEV1>80%
Stage 2 / moderate - FEV1 50-79%
Stage 3 / severe - FEV1 30-49%
Stage 4 - very severe - FEV1 <30%
COPD: conservative Mx?
- smoking cessation
- pneumococcal + flu jabs
- pulmonary rehab
COPD - describe stepwise medical Mx ?
1st step
- SABA / SAMA
2nd step:
if asthma/steroid responsive?
- LABA/ICS
Eg Fostair, Symbicort and Seretide =LABA and ICS combination inhalers
if not asthma/steroid responsive?
- LABA/LAMA
Eg Anoro Ellipta, Ultibro Breezhaler and DuaKlir Genuair = LABA and LAMA combination inhalers.
3rd Step:
- LABA / LAMA / ICS combination inhaler
Eg Trimbow, Trelegy Ellipta and Trixeo Aerospher
COPD: who is eligible for long term oxygen therapy?
severe COPD with chronic hypoxia (sats < 92%), polycythaemia, cyanosis or cor pulmonale.
what is cor pulmonale? why does it happen?
Right-sided heart failure caused by respiratory disease
- increased pressure and resistance in the pulmonary arteries (pulmonary hypertension) limits the right ventricle pumping blood into the pulmonary arteries. This causes back-pressure into the right atrium, vena cava and systemic venous system
causes of cor pulmonale?
COPD (the most common cause)
Pulmonary embolism
Interstitial lung disease
Cystic fibrosis
Primary pulmonary hypertension
what is an infective exacerbation of COPD?
- acute deterioration in sx in COPD pt
Causes - bacterial - H influenzae, strep pneumoniae, M catarrhalis
- Viral - human rhinovirus
IE-COPD Px?
- SOB, cough, wheeze
- increased sputum
- hypoxia, acute confusion
IE-COPD Ix?
- ABG
- Chest x-ray - pneumonia or other pathology
- ECG - arrhythmias or evidence of heart strain
- FBC to look for infection (raised white blood cells)
- U&E to check electrolytes, which can be affected by infections and medications
- Sputum culture
- Blood cultures in patients with signs of sepsis (e.g., fever
what would you see on ABG for someone with acute exacerbation of COPD?
- respiratory acidosis
Low pH indicates acidosis
Low pO2 indicates hypoxia and respiratory failure
Raised pCO2 indicates CO2 retention (hypercapnia)
Raised bicarbonate indicates chronic retention of CO2 - kidneys producing more bicarb to balance increased CO2 but cannot keep up with rate in exacerbation
IE-COPD Mx?
- regular inhalers (salbutamol / ipratropium)
- oxygen (+/- chest physio)
- 30mg prednisolone for 5d
- antibiotics
if severe …
5. IV aminophylline
6. NIV
7. Intubation and ventilation
what is asthma-COPD overlap syndrome?
clinical syndrome consisting of persistent airflow limitation (COPD) in someone >40 with a Hx of asthma/bronchodilator reversible airway disease
Mx = inhaled steroid + LABA
pneumonia - definition
- infection of lung tissue causing inflammation in alveolar space
NB inflammation + pus - impairs gas exchange
types of pneumonia?
CAP - community
HAP - >48hrs in hospital
VAP - intubated
Aspiration - fromm aspiration of foods/fluids
typical bacterial causes of pneumonia?
Most common:
- Strep pneumoniae (most common)
- H influenzae (COPD)
others:
- Moraxella catarrhalis – COPD / immunocompromised
- Pseudomonas aeruginosa – CF / bronchiectasis
- S aureus – CF
- MRSA – HAP
- Klebsiella – alcoholics
atypical causes of pneumonia?
Atypical - cannot be cultured or gram stained in normal way
Legions – Legionella pneumophila = air con units
Psittaci – Chlamydia psittaci = contact with birds
M – Mycoplasma pneumoniae = erythema multiforme
C – Chlamydophila pneumonia = mild in children
Qs – Q fever (coxiella burnetii) = animal bodily fluid
Other
- Pneumocystis jirovecii pneumonia (PCP) – immunocompromised, eg HIV with low CD4 – dry cough, SOBOE, night sweats, co-trimoxazole to tx
- COVID-19
pneumonia symptoms?
Cough
Sputum production
Shortness of breath
Fever
Feeling generally unwell
Haemoptysis (coughing up blood)
Pleuritic chest pain (sharp chest pain, worse on inspiration)
Delirium (acute confusion)
signs of pneumonia on chest examination?
- bronchial breathing
- focussed coarse crackles
- dull to percuss (lung filled with sputum)
CURB-65 scoring system?
C – confusion
U – urea >7mmol/L
R – resp rate >30
B – BP<90 systolic / 60 diastolic
65 – age >65yo
- Score 0-1 – mild, consider home tx
- Score 2– moderate, hospital admission
- Score 3-5 – severe, admit, monitor, consider ITU
pneumonia Ix?
- Chest x-ray - look for focal consolidation
- Bloods (FBC, U&E, CRP)
- sputum cultures
- blood culture
- pneumococcal / legionella urinary antigen tests
pneumonia Mx?
Mild:
usually 5 days of amoxicillin / doxy / clari
Moderate / Severe?
- IV Abx
- respiratory support
acute bronchitis - Px, Ix and Mx?
self limiting URTI involving inflammation of bronchi
- usually viral
Px
- cough +/- sputum
- sore throat
- rhinorrhoea
- wheeze
- fever
DDx from pneumonia
- may have no sputum/wheeze/SOB
- no focal chest signs
Ix - clinical dx
Mx
1. smoking cessation
2. simple analgesia
3. ABx e..g doxy or amoxicillin
lung cancer RFs?
- smoking, occupational (asbestos, coal, tar etc), radiation, pulm fibrosis, COPD
2 histological types of lung cancer?
Small cell lung cancer (SCLC) - 20%
- NE hormones released -> paraneoplastic
Non-small cell lung cancer (NSCLC) - 80%
- adenocarcinoma - 40% - often seen in non-smokers
- squamous cell - 20% - cavitating lesions
- large cell - 10%
- other - 10%
lung cancer Px?
Shortness of breath
Cough
Haemoptysis (coughing up blood)
Finger clubbing
Recurrent pneumonia
Weight loss
Lymphadenopathy – often supraclavicular nodes are the first to be found on examination
extra pulmonary manifestations of lung cancer: name 2 possible associated nerve palsies?
Recurrent laryngeal nerve palsy = hoarse voice. Caused by a tumour pressing on or affecting the recurrent laryngeal nerve as it passes through the mediastinum.
Phrenic nerve palsy, due to nerve compression, causes diaphragm weakness and SOB
what triad makes up Horner’s syndrome and what tumour can cause it?
- partial ptosis, anhidrosis and miosis
- Pancoast tumour - pressing on sympathetic ganglion
extra pulmonary manifestation caused by ectopic ADH secretion by SCLC? ectopic ACTH by SCLC?
- SIADH - ectopic ADH from SCLC - Px with hyponatraemia
- Cushing’s syndrome - ectopic ACTH from SCLC - HTN, hyperglycaemia, hypokalaemia, alkalosis
why could lung cancer manifest with hypercalcaemia?
Hypercalcaemia can be caused by ectopic parathyroid hormone secreted by squamous cell carcinoma.
lung cancer patient with proximal weakness, diplopia and ptosis - what might have happened?
Lambert-Eaton myasthenic syndrome
- ABs against SCLC also target Ca channels in presynaptic motor neurons
name 5 key signs/symptoms that warrant a 2ww CXR in patients over 40
Clubbing
Lymphadenopathy (supraclavicular or persistent abnormal cervical nodes)
Recurrent or persistent chest infections
Raised platelet count
Chest signs of lung cancer
NICE guidelines surrounding unexplained symptoms and CXR for possible lung cancer referrals?
Two or more unexplained symptoms in patients that have never smoked
One or more unexplained symptoms in patients that have ever smoked or had asbestos exposure
unexplained Sx:
Cough
Shortness of breath
Chest pain
Fatigue
Weight loss
Loss of appetite
lung cancer Ix?
- CXR
- staging CT
- peT scan
- bronchoscopy
- biopsy + histology
CXR findings suggesting lung cancer?
Hilar enlargement
Peripheral opacity (a visible lesion in the lung field)
Pleural effusion (usually unilateral in cancer)
Collapse
lung cancer Mx?
SCLC
- chemo / radio
- stents / debulking surgery
- poor prognosis
NSCLC
- surgery - segmentectomy/wedge resection, lobectomy, pneumonectomy
- radiotherapy
- chemo
mesothelioma - definition?
- Tumour of mesothelial cells - 80-90% in pleura - other sites are peritoneum, pericardium, testes
- associated w asbestos - 45yr latent period
- high-grade, may invade intercostal nerves, severe pain
mesothelioma Px?
- chest pain
- SOB
- wt loss
- finger clubbing
- recurrent pleural effusions
- mets - lymphadenopathy, hepatomegaly, bone pain/tenderness, abdo pain/obstruction
mesothelioma Ix?
- CXR/CT - unilateral pleural thickening/effusion
- pleural aspiration - bloody
- pleural biopsy
mesothelioma Mx?
- resistant to surgery/chemo/radio
- palliative chemo
PE - definition and patho?
thrombus (blood clot) in pulmonary arteries
- venous thrombus, usually from DVT
- obstructs RV outflow - sudden increase in pulmonary vascular resistance - acute RHF
- lung tissue ventilated, not perfused - V/Q mismatch
PE risk factors?
- Immobility
- Recent surgery
- Long-haul flight
- Pregnancy
- Oestrogen therapy - cOCP, HRT
- Malignancy
- Polycythaemia
- SLE
- Thrombophilia
VTE prophylaxis options
- Assess for VTE risk
- LMWH (enoxaparin) if higher risk - CI - active bleeding, warfarin/DOAC
- Anti-embolic compression (stockings CI - PAD
PE Px?
- SOB
- Cough
- Haemoptysis
- Pleuritic chest pain
- Hypoxia
- Tachycardia
- Raised RR
- Low-grade fever
- Hypotension
- May have DVT sx
PE: what is PERC rule and when is it used?
PERC is used when the clinician estimates less than a 15% probability of a pulmonary embolism to decide whether further investigations for a PE are needed
PE: what is Wells score used for?
predicts the probability of a patient having a PE - used when PE is suspected.
PE Ix?
- PERC rule
- PE Wells score
If PE likely (>4) then CTPA
- positive = dx
- negative = consider leg USS
if PE unlikely (<4) then D dimer
- positive = CTPA
- negative = stop anticoagulation, alt dx
can perform V/Q scanning - maybe if renal impairment
Possible ABG findings in PE patient?
- respiratory alkalosis
hypoxia = raised RR –> blow off CO2 –> makes blood alkaloid
PE Mx/
- oxygen, analgesia
haemodynamically stable?
- DOAC (apixaban/rivaroxaban) for 3 months
- if CI? LMWH
haemodynamically unstable?
- unfractionated heparin whilst considering thrombolysis
- thrombolysis (streptokinase/alteplase)
- post thrombolysis - switch to DOAC
anticoagulation Tx length after PE?
Anticoagulation length
- all pts - 3mo
- provoked - stop after 3mo (3-6mo if active cancer)
- unprovoked - 6mo total
- ORBIT score - assess bleeding risk
what is a pleural effusion?
- fluid in pleural space
- empyema - pus
- chylothorax - lymphatic fluid - trauma / carcinoma infiltration
definition of a exudative pleural effusion?
high protein content (more than 30g/L)
give 3 causes of exudative pleural effusion?
- related to inflammation - inflammation results in protein leaking out of the tissues into the pleural space
Cancer (e.g., lung cancer or mesothelioma)
Infection (e.g., pneumonia or tuberculosis)
Rheumatoid arthritis
definition of transudative pleural effusion?
lower protein content (less than 30g/L)
causes of transudative pleural effusion?
relates to fluid moving across or shifting into the pleural space
- Congestive cardiac failure
- Hypoalbuminaemia
- Hypothyroidism
- Meigs syndrome
what is meig’s syndrome?
triad of:
- benign ovarian tumour (usually a fibroma)
- pleural effusion
- ascites
pleural effusion Px?
- sob
- chest pain
- Dullness to percussion over the effusion
- Reduced breath sounds
- Tracheal deviation away from the effusion in very large effusions
pleural effusion Ix?
- CXR
- USS
- contrast CT
- pleural aspiration - send for pH, protein, LDH, cytology, micro
4 pleural effusion CXR findings?
- blunting of costophrenic angle
- fluid in lung fissures
- tracheal / mediastinal deviation
- large effusionnn? may see meniscus
interpreting pleural aspiration
- Low glucose - RA, TB
- Raised amylase - pancreatitis, oesophageal perf
- Blood - mesothelioma, PE, TB
- Empyema - pus, low pH, low glucose, high LDH
what is Lights criteria?
Differentiate between transudate / exudate where protein 25-35. Exudate likely if at least one of the following is met:
- Pleural fluid protein / serum protein >0.5
- Pleural fluid LDH / serum LDH >0.6
- Pleural fluid LDH >2/3 upper limit normal of normal serum LDH
pleural effusion Mx?
- tx cause
- pleural aspiration
- chest drain
Empyema
- chest drain
- Abx
Recurrent
- recurrent aspiration
- pleurodesis
- indwelling pleural catheter
- opioids for SOB
PTX definition?
- air in pleural cavity causing lungs to separate from chest wall , can collapse lung
4 causes of PTX?
Primary spontaneous PTX (PSP) - no underlying disease
Secondary spontaneous PTX (SSP) - COPD, asthma, CF, cancer, PCP, Marfan’s
Traumatic - blunt / penetrating
Iatrogenic - caused by medical intervention eg thoracentesis, CVC, ventilation
what is a tension PTX?
PTX caused by trauma to the chest wall that creates a one-way valve that lets air in but not out of the pleural space –> air is trapped and pressure in thorax increases
4 signs of a tension PTX?
- Tracheal deviation away from the side of the pneumothorax
- Reduced air entry on the affected side
- Increased resonance to percussion on the affected side
- Tachycardia
- Hypotension
Mx of tension PTX?
Insert a large bore cannula into the second intercostal space in the midclavicular line
PTX Px?
- sudden onset SOB
- pleuritic CP
- hyper-resonant
- reduced AE
- reduced chest expansion
- tachypnoea, tachycardia
- surgical emphysema
PTX Ix?
- CXR
- CT thorax
what can make a PTX patient high risk?
haemodynamic compromise, bilateral pneumothorax,
hypoxia
underlying lung disease
PTX Mx?
If no sx = conservative mx
low risk and PTX < 2cm = conservative
PTX > 2cm = conservative / pleural vent / needle aspiration / chest drain
management of recurrent / persistent PTX?
- video-assisted thoracoscopic surgery (VATS) for mechanical / chemical (talc) pleurodesis +/- bullectomy / pleurectomy
what makes up the chest drain triangle of safety?
- 5th intercostal space (or the inferior nipple line)
- Midaxillary line (or the lateral edge of the latissimus dorsi)
- Anterior axillary line (or the lateral edge of the pectoralis major)
key info to give on discharge after PTX?
- avoid smoking
- if ptx persists - cannot fly
- avoid scuba diving - unless undergone bl surgical pleurectomy, normal PFTs/chest CT post-op
bronchiectasis - definition + patho
Permanent dilation of the bronchi, the large airways that transport air to the lungs
- Sputum collects and organisms grow in the wide tubes, resulting in a chronic cough, continuous sputum production and recurrent infections
bronchiectasis causes?
Idiopathic (no apparent cause)
Pneumonia
Whooping cough (pertussis)
Tuberculosis
Alpha-1-antitrypsin deficiency
Connective tissue disorders (e.g., rheumatoid arthritis)
Cystic fibrosis
Yellow nail syndrome
OSCE: what triad makes up yellow nail syndrome ?
- yellow fingernails
- bronchiectasis
- lymphoedema
bronchiectasis: key symptoms?
Shortness of breath
Chronic productive cough
Recurrent chest infections
Weight loss
bronchiectasis signs on examination?
Sputum pot by the bedside
Oxygen therapy (if needed)
Weight loss (cachexia)
Finger CLUBBING
Signs of cor pulmonale (e.g., raised JVP and peripheral oedema)
Scattered crackles throughout the chest that change or clear with coughing
Scattered wheezes and squeaks
bronchiectasis Ix?
- sputum culture
- CXR - tram-track opacities, ring shadows
- HRCT - dilated/thickened bronchi, signet ring sign
- spirometry - obstructive
- bronchoscopy
most common infective organisms in bronchiectasis?
Haemophilus influenza
Pseudomonas aeruginosa
bronchiectasis Mx?
- vaccines
- chest physio, postural drainage
- long-term abx - azithromycin - if 3+ exacerbations/yr
- bronchodilators
- surgical resection
- lung transplant
management of infective exacerbation of bronchiectasis?
- extended abx course for exacerbations (7-14d)
- pseudomonas - cipro
- H influenzae - amoxicillin, co-amox, doxy
- S aureus - fluclox
obstructive sleep apnoea?
- collapse of pharyngeal airways whilst asleep leading to apnoeas
OSA RFs?
- middle aged, male
- obesity
- alcohol
- smoking
- macroglossia
- large tonsils
- Marfan’s
OSA Px?
- Partner may report excessive snoring, periods of apnoeas
- Morning headache
- Waking up unrefreshed from sleep
- Daytime sleepiness
- Concentration problems
- Reduced O2 sats during sleep
- Severe - HTN, HF, increased risk of MI / stroke
OSA Ix?
- Epworth sleepiness scale
- Multiple Sleep Latency Test (MSLT)
- sleep studies
OSC Mx?
- reduce alcohol, stop smoking, lose weight
- CPAP
- intra-oral devices - eg mandibular advancement
- surgery - uvulopalatopharyngoplasty (UPPP)
- inform DVLA if daytime sleepiness
name some occupational lung disorders?
Inhaling something at work, leads to:
- acute bronchitis, oedema
- Pulmonary fibrosis
- Occupational asthma
- Hypersensitivity pneumonitis
- Bronchial carcinoma
what is occupational asthma?
- asthma sx worse at work
- peak flow diary to compare work/home
what is pneumoconiosis? who is affected?
- inhalation of coal dust, fibrosis occurs
- coal mine workers -> coal-workers pneumoconiosis (CWP)
what is silicosis?
- inhalation of silica particles - fibrogenic
- upper zone fibrosis, egg-shell calcification of hilar lymph nodes
- eg stonemasons, sandblasters, pottery
- massive airways restriction
what iis asbestosis?
lung fibrosis related to asbestos exposure
asbestos inhalation causes:
- Lung fibrosis
- Pleural thickening and pleural plaques
- Adenocarcinoma
- Mesothelioma
NB can get lung cancer
what might you see on CXR of someone with asbestos related lung diseasE?
- pleural plaques - these have no potential for malignancy
- effusion
Byssinosis
- inhalation of textile fibre dust
- chest tightness, cough, SOB
- Sx worse first day back at work after break
Berylliosis
- inhalation of copper alloy
- aerospace, electrical devices
- progressive SOB, pulm fibrosis
Pulmonary siderosis
- inhalation of metallic particles - metal grinding, welding
- little effect on lung function
what is pulmonary fibrosis?
- diseases that cause lung fibrosis - scarring of lungs, loss of elasticity
- an interstitial lung disease (ILD)
what is ILD?
ILD includes many conditions that cause inflammation + fibrosis of lung parenchyma
Examples:
- Idiopathic pulmonary fibrosis
- secondary pulmonary fibrosis
- EAA
- cryptogenic organising pneumonia
- asbestosis
idiopathic pulmonary fibrosis Px?
- SOBOE
- dry cough
- fatigue
O/E bibasal fine end-inspiratory crackles, clubbing
ILD Ix?
- Clinical features
- High-resolution CT scan (HRCT) of the thorax (showing a typical “ground glass” appearance)
- Spirometry –> FEV1&FVC reduced, FEV1:FVC >70%
If in doubt:
- lung biopsy
- bronchoalveolar lavage
Mx of ILD?
- Remove or treat the underlying cause
- Home oxygen where there is hypoxia
- Stop smoking
- Physiotherapy and pulmonary rehabilitation
- Pneumococcal and flu vaccine
- Advanced care planning
what are 2 medications licensed to slow progressive of idiopathic pulmonary fibrosis?
Pirfenidone - reduces fibrosis and inflammation
Nintedanib - reduces fibrosis and inflammation by inhibiting tyrosine kinase
name 4 drugs that can cause secondary pulmonary fibrosis?
Amiodarone (also causes grey/blue skin)
Cyclophosphamide
Methotrexate
Nitrofurantoin
which conditions are associated with pulmonary fibrosis?
Alpha-1 antitrypsin deficiency
Rheumatoid arthritis
Systemic lupus erythematosus (SLE)
Systemic sclerosis
Sarcoidosis
what is hypersensitive pneumonitis / Extrinsic allergic alveolitis (EAA)?
type III and type IV hypersensitivity reaction to an environmental allergen - leads to lung inflammation and damage
- form of ILD
Bird-fancier’s lung – reaction to bird droppings
Farmer’s lung – reaction to mouldy spores in hay
Mushroom worker’s lung – reaction to specific mushroom antigens
Malt workers lung – reaction to mould on barley
EAA Px
Acute (4-8hrs post-exposure)
- SOB, dry cough, fever, rigors, chest tightness
- crackles on ausc
- resolves after Ag removed
Chronic (wks/months)
- lethargy
- SOB
- productive cough
- anorexia, wt loss
EAA Ix?
- CXR / CT - upper/mid zone fibrosis
- Bloods - assay for specific IgG
- Spirometry - restrictive
- bronchoscopy + bronchoalveolar lavage = lymphocytes in hypersensitivty pneumona
EAA Mx?
- avoid trigger
- steroids - oral prednisone
- O2 if necessary
what is pulmonary hypertension?
- increased resistance and pressure in the pulmonary arteries
- causes strain on the right side of the heart as it tries to pump blood through the lungs
- results in back pressure through the right side of the heart and into the systemic venous system.
defined as mean pulmonary arterial pressure of > 20 mmHg
what causes PAH?
Group 1 – Idiopathic pulmonary hypertension or connective tissue disease (e.g., systemic lupus erythematous)
Group 2 – Left heart failure, usually due to myocardial infarction or systemic hypertension
Group 3 – Chronic lung disease (e.g., COPD or pulmonary fibrosis)
Group 4 – Pulmonary vascular disease (e.g., pulmonary embolism)
Group 5 – Miscellaneous causes such as sarcoidosis, glycogen storage disease and haematological disorders
how might PAH Px?
- SOB
- Syncope
- Cough
- Tachycardia
- Raised JVP
- Hepatomegaly
- Peripheral oedema
- Hypotension
PAH Ix?
- ECG - RH strain, RAD, RBBB, RVH, p pulmonale
- CXR - RVH, dilated pulmonary arteries
- ECHO
- BNP raised
PAH Mx options?
Idiopathic pulmonary hypertension may be treated with:
- Calcium channel blockers
- Intravenous prostaglandins (e.g., epoprostenol)
- Endothelin receptor antagonists (e.g., macitentan)
- Phosphodiesterase-5 inhibitors (e.g., sildenafil
secondary PAH?
- Tx cause e.g. COPD, PE, SLE
what is sarcoidosis?
- Chronic multisystem granulomatous disorder of unknown cause
- granulomas = inflammatory nodules full of macrophages
NB can have non pulmonary manifestations e.g. erythema nodosum
sarcoidosis risk factors?
- Aged 20-39 or around 60
- Women
- Black ethnic origin
possible skin features of sarcoidosis?
- erythema nodosum
- lupus pernio - raised purple lesions on nose/cheeks
how might acute sarcoidosis present?
- cough
- SOB
- fatigue
- fever
- weight loss
- arthralgia
- erythema nodosum
which organ is most commonly affected by sarcoidosis?
lungs - in over 90% patients
name 3 organs (except lungs) that might be affected by sarcoidosis and explain how?
liver: nodules, cirrhosis, cholestasis
eyes: uveitis, conjunctivitis, optic neuritis
heart: BBB, heart block, myocardial involvement
kidneys: stones, interstitial nephritis
what is Lofgren syndrome?
specific presentation of sarcoidosis with a classic triad of symptoms:
- Erythema nodosum
- Bilateral hilar lymphadenopathy
- Polyarthralgia
key blood test findings in sarcoidosis?
- Raised ACE - often used as screening test
- Raised calcium
what might a lymph node biopsy show in sarcoidosis?
non-caseating granulomas with epithelioid cells.
what imaging can you do for sarcoidosis? what might you seE?
Chest x-ray may show hilar lymphadenopathy
High-resolution CT scanning may show hilar lymphadenopathy and pulmonary nodules
MRI can show central nervous system involvement
PET scan can show active inflammation in affected areas
sarcoidosis Mx?
- mild sx - conservative
1. oral steroids for 6-24m - prednisolone + bisphosphonates
2. methotrexate
3. lung transplant
NB spontaneous resaves in 50% patients
lung abscesses? most common causative organism?
- well-circumscribed infection within lung parenchyma, contains pus
- RFx: necrotising pneumonia, septic emboli, tumours, aspiration
- S aureus, Klebsiella, Pseudomonas, but typically polymicrobial
Px of lung abscess?
- swinging fevers
- foul tasting purulent sputum
- cough
- pleuritic pain
- haemoptysis
- tachypnoea
- clubbing
Ix of lung abscess?
- CXR - walled cavity +/- fluid level
- sputum + blood cultures
- sepsis workup
lung abscess Mx?
- IV abx
- bromchoscopic drainage
- surgical resection
what is TB?
- infection caused by Mycobacterium tuberculosis
- acid-fast bacilli - see with zeihl Neilson stain - bright red cells on blue background
TB pathophysiology - how is is spread? what are the 4 possible outcomes once bacteria is in bodY?
- spread by saliva droplets, then several possible outcomes:
- Immediate clearance
- most cases - Primary active TB - active infection after exposure
- Latent TB - presence of bacteria without being symptomatic or contagious
- Secondary TB - reactivation of latent TB to active infection
what is miliary TB?
when immune system can’t control infection and disseminated and severe disease develops
RFs of TB?
- close contact - household member
- relatives from high prevalence areas
- immunocompromised
- malnutrition, homelessness, drug users, smokers, alcoholics
what is the BCG vaccine?
- intradermal, live attenuated M bovis bacteria
- generates immune response
- test with Mantoux test first - only give if negative
- NOT part of routine vaccine schedule
TB Px (systemic, pulmonary and extrapulmonary symptoms)
Systemic sx
- fever, lethargy, night sweats, wt loss, lymphadenopathy
Pulm sx
- cough, haemoptysis, chest pain, consolidation, pleural effusion
Extrapulmonary sx
- Bone – bone pain, Pott’s
- Abdo – ascites, lymph nodes, ileal malabsorption
- GU – epididymitis, LUTS, pyuria
- CNS – meningitis, sx of raised ICP
- Cardiac – pericarditis, pericardial effusion
- Skin – lupus vulgaris (red/brown lesions), erythema nodosum
TB Ix - for immune response and active disease
For immune response - previous infection, latent TB, active TB
- mantoux test
- IGRA
For active disease
- CXR
- cultures - sputum (3x), blood, lymph node aspiration/biopsy - caseating granuloma on histology
- NAAT
what might you see on a TB CXR?
- primary TB: patchy consolidation, pleural effusions and hilarious lymphadenopathy
- reactivated TB: nodule consolidation
- disseminated miliary TB: ‘millet seeds’ (small nodules) distributed across lungs
Latent TB Mx?
Either:
Isoniazid and rifampicin for 3 months (with pyridoxine vit B6)
Or
Isoniazid for 6 months (with pyridoxine vit B6)
why prescribe pyridoxine / vitamin B6 with isoniazid?
isoniazid causes peripheral neuropathy
active TB mx?
R – Rifampicin for 6 months
I – Isoniazid for 6 months
P – Pyrazinamide for 2 months
E – Ethambutol for 2 months
- isolate patient and inform UKHSA
common S/E of rifampicin?
- red/orange discolouration of secretions, such as urine and tears
- induced cytochrome P450 enzymes so reduces effect of COCP
- hepatic
common S/E of pyrazinamide?
hyperuricaemia (high uric acid levels), resulting in gout and kidney stones
- hepatotoxic
common S/E of ethambutol?
- colour blindness and reduced visual acuity
- hepatotoxic
influenza?
- acute resp illness from infection with influenza virus
- RNA virus with 3 subtypes (A, B and C)
- A strains can be divided in H and N subtypes e.g. H1N1 (Spanish flu)
who is eligible for free flu vaccines?
Aged 65 and over
Young children
Pregnant women
Chronic health conditions, such as asthma, COPD, heart failure and diabetes
Healthcare workers and carers
influenze Px?
- 1-4d incubation period
- Fever
- Lethargy
- Anorexia
- Myalgia, joint pain
- Headache
- Dry cough
- Sore throat
- Coryzal sx
how can we clinically differentiate between common cold and flu?
- flu more abrupt onset
- flu typically has fever
- feel ‘wiped out’ with flu + muscle aches
influenza Ix?
- clinical dx
- POCT / viral PCR to monitor outbreaks
influenza Mx?
- self-care
if at risk of complications?
- antivirals - tamiflu (oseltamivir), inhaled zanamivir - start <48hrs of sx onset for it to be effective
ARDS - Px?
- resp distress, SOB, elevated RR
- bl lung crackles
- hypoxia
what is ARDS?
acute respiratory distress syndrome
characterised by:
1. onset within 7 days of triggering event
2. bilateral opacities seen on CXR/CT
3. respiratory failure
causes of ARDS?
- sepsis, pneumonia, trauma, massive blood transfusion, smoke inhalation, pancreatitis
ARDS - Ix and Mx?
Ix
- CXR - bilateral infiltrates
- ABG - hypoxia, resp failure
Mx
1. Tx trigger e.g. sepsis/trauma
2. oxygen
3. CPAP + O2
4. mechanical ventilation
5. prone positioning