RESP: CF, Brochiectasis and OSA Flashcards
Causes of bronchiectasis?
Post infective- Whooping cough/TB
Immune deficiency- Hypogammaglobulinaemia
Genetic- CF, primary cilary kinesia, young’s syndrome, kartagener syndrome
Obstruction- foreign body, tumour
Toxic insult- gastric aspiration,
Secondary immune deficiency- HIV
Appearance of bronchiectasis on CT?
Signet rings
What is Young’s syndrome?
Triad of bronchiectasis, sinusitis, and reduced fertility
Bronchiectasis common organisms?
Haemophilius influenzae Non- tuberculous mycobacteria Fungi- aspergillus, candida Pseudomonas aeruginosa Moraxella catarrhalis Stenotrophomonas maltophilia
Management of bronchiectasis?
Treat underlying cause
Antibiotics/ IV for severe infection
Flu and Covid vaccines
Bronchodilators
Antibiotic prophylaxis for those with recurrent infections
Physiotherapy for mucus/airway clearance
Pulmonary Rehab – MRC Dyspnoea Score >3
What is the MRC dyspnoea score?
Used to assess the degree of baseline functional disability due to dyspnoea.
Breatheless with strenuous exercise-0
Breathless when walking up slight hill 1
Walk slower than people their age due to breathlessness/ has to stop walking due to breathlessness 2
Stop walking after 100m as am breathless 3
Too breathless to leave the house/ breathless when dressing/ undressing- 4
How to identify pt with acute exacerbation of bronchiectasis
A person with bronchiectasis with a deterioration in 3 or more key symptoms for at least 48 hours:
Cough
Sputum volume and / or consistency
Sputum purulence
Breathlessness and / or exercise tolerance
Fatigue
Haemoptysis
What can CF be diagnosed based on?
One or more characteristic phenotypic features OR history of CF in a sibling OR positive newborn screening test result
PLUS:
Increased sweat chloride concentration (>60mmol/L Na+, Cl-) in sweat test
OR
Identify of two CF mutations - genotyping
OR
Demonstration of abnormal nasal epithelial ion transport
Note: Quesbook says the following:
- Neonatal heel prick day between day 5 and day 9
- Sweat test: sweat sodium and chloride >60mmol/L
- Faecal elastase: this can provide evidence for abnormal pancreatic exocrine function.
- Genetic screening: This can identify CF mutations
Pathophysiology of CF?
Autosomal receive condition.
Mutation in CFTR gene (which usually regulates sodium channel called ENAC)
Mutation in CFTR gene
—> increases Na+ absorption
—> get abnormal Chloride secretion (as CFTR usually codes cAMP regulated chloride channel) in epithelial cells lining the airways,
—>less water secreted
—> OVERALL: get thicker mucus= impair cilia function
Presenting features of CF?
Presenting features:
- Meconium ileus:
is in newborns, bowel is blocked by sticky secretions. Have signs of intestinal obstruction soon after birth - billows vomiting, abdominal distension, delay in passing meconium.
- Intestinal malabsorption:
main cause is severe deficiency of pancreatic enzymes - Recurrent chest infections
- Newborn screening
Respiratory features of CF?
Chronic sinusitis Nasal polyps Cough Wheeze Haemoptysis Recurrent LRTI Bronchiectasis Pneumothorax Cor pulmonale Respiratory failure
Apart from respiratory system, CF causes multi-organ damage. What are features of damage in:
1. GI system?
- Pancreatic insufficiency, so have DM and/or steatorrhea
Cirrhosis
Portal HTN
Gallstones
Apart from respiratory system, CF causes multi-organ damage. What are features of damage in:
2.. Reproductive system?
- Male infertility
Apart from respiratory system, CF causes multi-organ damage. What are features of damage in:
3. MSK?
- Clubbing
Arthritis
Osteoporosis
Investigations in known CF patients (to monitor disease aseverity, assess symptoms etc)?
Sputum culture - chest infection Glucose tolerance test - assess DM Bloods - FBC, U+Es, coat screen, vitamins, blood sugar, bone profile Spirometry: obstructive defect Aspergillus skin prick test or serology
Imaging: CXR - bronchiectasis, hyperinflation
Abdominal ultrasound - Distal Intestinal Obstruction, liver cirrhosis, chronic pancreatitis
Lifestyle advice for pts with CF?
No smoking
Avoid other CF pts
Avoid friends/relatives with colds and infections
Avoid jaccuzis (pseudomonas)
Clean and dry nebulisers thoroughly
Avoid stables, compost or rotting veg - Aspergillus inhalation
Annual flu vaccine
Sodium chloride tablets in hot weather/exercise
Medical management for infective exacerbation of CF?
- Antibiotics, although for patients with recurrent chest infections prophylactic long-term antibiotics may be prescribed.
- Nebulised mucolytics (Dornase Alfa)
- Bronchodilators (Inhaled corticosteroids or B2-agonists)
Medical management for pancreatic insufficiency in CF?
Insulin replacement
Creon - exocrine enzymatic replacement
Vitamins - A, D, E, K
Medical management for worsening progressive lung disease in CF?
Oxygen therapy
Ventilation
Diuretics (especially if have cor pulmonale)
Management of CF?
Physio airway clearance Exercise Mucolytic treatment Pancreatic enzyme replacement therapy Fat soluble vitamin replacement Long term abx Optimise CF related DM - insulin therapy Novel CFTR modulators = Kaftrio Long term monitoring for CF related DM, CF related liver disease, osteoporosis.
What are you differentials for Haemoptysis : infection related?
Pneumonia
Tuberculosis
Bronchiectasis / CF
Cavitating lung lesion (often fungal
What are you differentials for Haemoptysis : Malignancy related?
Lung cancer
metastases
What are you differentials for Haemoptysis : Haemorrhage related?
Bronchial artery erosion
Vasculitis
Coagulopathy
What are some differentials for Haemoptysis? Other (resp = clue)
PE!
Clinical definition of obstructive sleep apnoea?
Upper airway narrowing, provoked by sleep, causing sufficient sleep fragmentation. Results in daytime sleeping
Characteristic physical features of pt with obstructive sleep apnoea?
Male
Upper body obesity - collar size >17inches
Undersized/set back mandible
Definition and Pathophysiology of obstructive sleep apnoea?
Obstructive sleep apnoea (OSA) is a sleep disorder caused by recurrent episodes of complete or partial collapse of the upper airway, causing obstruction of airflow and therefore apnoeic episodes.
It is normal for muscle tone to reduce when asleep, in these patients the innate tone of the pharynx is overcome, which causes it to collapse on itself, obstructing the airway. This induces hypoxia and therefore a reactive episode of transient arousal to reopen the airway. Overall overnight ventilation is impaired and CO2 levels increase.
Causes of small pharyngeal size?
Obstructive Sleep apnoea
Fatty infiltration of pharyngeal tissues and external pressure from increased neck fat/muscle bulk
Large tonsils
Craniofacial abnormalities
Extra submucosal tissue = e.g in myxoedema
Causes of excessive narrowing of the airway during sleep?
Obesity
Neuromuscular disease with pharyngeal involvement - leads to greater loss of dilator muscle tone e.g stroke, myotonic dystrophy, motor neurone disease
Muscle relaxants - sedatives, alcohol
Increasing age
Clinical features (signs and symptoms) of obstructive sleep apnoea?
Unrefreshed sleep
Snoring and apnoea attacks witnessed by partner
Excessive daytime sleepiness
Nocturia
Less common in booklet: Nocturnal sweating, reduced libido, oesophageal reflux
What is Epworth sleepiness scale?
A questionnaire completed by patient +/- partner to assess chance of having obstructive sleep apnoea. 0 = would not doze. 1 = slight chance. 2 = moderate chance. 3 = high chance. 0-3 given for each question, score out of 24 given.
What kind of questions are asked in Epworth sleepiness scale?
Sleep when:
- sitting and reading
- watching tv
- sitting in public place
- passenger in a car for an hour
- lying down to rest in the afternoon
- sitting and talking
- sitting quietly after lunch without alcohol
- in a car, while stopped in traffic
What sleep studies can be done to diagnose obstructive sleep apnoea?
Overnight oximetry alone
Limited sleep study
Full polysomnography
What is included in limited sleep study to diagnose obstructive sleep apnoea?
- Oximetry
- Snoring
- body movement
- HR
- oronasal flow
What simple approaches can you suggest for obstructive sleep apnoea managed?
Note: Treatment is based on symptoms/QofL. Need to consider livelihood too
Simple approaches: Weigh loss, sleep on side (decubitus), not supine. Avoid or reduce evening alcohol intake
How to manage mild obstructive sleep apnoea/ snorers?
Mandibular advancement devices
Consider pharyngeal surgery
How to manage significant obstructive sleep apnoea?
Nasal CPAP, consider gastric bypass.
Rare: tracheostomy
How to manage severe obstructive sleep apnoea and CO2 retention?
Non-invasive ventilation before CPAP if acidotic.
Note: compensated CO2 may reverse with CPAP only. (So treatment here is individualised).
What is CPAP in obstructive sleep apnoea?
Continuous positive airway pressure - helps keep airway open so prevents sleep apnoea
How is CPAP delivered?
What is air pressure?
Via nasal mask. Can also use mouth and nose mask.
Air pressure is 10cm H2O pressure = this splints open the upper airways.
Benefit of CPAP for obstructive sleep apnoea?
Prevents airways collapse
Prevents fragmented sleep
Prevents daytime somnolence
Opens collapsed alveoli - improves V/Q match
CPAP (continous positive airway pressure) vs NIV (non-invasive ventilation)?
Biggest contrast:
CPAP supplies constant positive pressure in inspiration and expiration = so is NOT a form of ventilatory support.
NIV has two levels of positive pressure - one for inspiration and one for expiration = so IS A form of ventilatory support.
Additional from booklet:
CPAP can be used in patients with acute respiratory failure (palm oedema) to help oxygenation,
NIV can be set up with back up rates so the machine operates when RR drops below a certain level.
Gold standard investigation for bronchiectasis?
High resolution (1/2) CT (1/)
