Stridor and Sleep Apnoea Flashcards
What structures of the upper airway normally sit above the trachea?
- larynx
- subglottis
How is stridor defined?
- inspiratory wheeze
- due to large airway obstruction
=> (larynx/trachea/major bronchi)
What are the most common causes of stridor in children?
Infections
Foreign Body
Anaphylaxis / angioneurotic oedema
Other (eg burns)
What infections can cause stridor in children?
- Croup (or Pseudomembranous croup)
- Epiglottitis
- Retropharyngeal abscess
- Diphtheria
- Infectious mononucleosis
What can cause stridor in adults?
- Cancers
- Anaphylaxis
- Goitre (retrosternal)
- Foreign body
- Trauma (eg strangulation, burns, irritant gases)
- Other (eg vocal cord palsy; Wegener’s granulomatosis)
What cancers may cause stridor in adults?
- Larynx
- Trachea
- Major bronchi
What is tracheomalacia and when may this cause stridor?
- flaccidity of supporting tracheal cartilage
=> widening of the posterior membranous wall
=> reduced trachea diameter
This causes tracheal collapse
- especially during times of increased airflow
=> coughing, crying, or feeding
How is stridor investigated?
- Laryngoscopy (beware in acute epiglottitis)
- Bronchoscopy
- Flow volume loop
- CXR
- Other imaging (CT; thyroid scan)
How is laryngeal obstruction treated?
- Treat underlying cause
=> eg foreign body removal (Heimlich Manoeuvre) anaphylaxis (adrenaline) - Mask bag ventilation with high flow O2
- Cricothyroidotomy
- Tracheostomy
How is malignant airway obstruction treated?
- Tumour removal
=> laser; photodynamic therapy; cryotherapy; diathermy; surgical resection - Tumour compression
=> intraluminal stent - Radiotherapy
=> external beam; brachytherapy - Chemotherapy
What symptoms would indicate a patient is in acute anaphylaxis?
- Flushing, pruritus, urticaria,
- Angioneurotic oedema (lips, tongue, face, larynx, bronchi)
- Hypotension (vasodilatation and plasma exudation) circulatory collapse (shock)
- Stridor, wheeze and respiratory failure
WHat can potentially cause anaphylaxis in patients?
Foods eg nuts; shellfish
Insect venom (bee, wasp)
Drugs (eg penicillin, aspirin, anaesthetics)
Other eg latex
How is anaphylaxis treated?
IM Adrenaline IV antihistamine IV corticosteroid High flow O2 Nebulised bronchodilators Endotracheal intubation if necessary
How is anaphylaxis prevented?
Allergen avoidance (where possible)
Desensitisation (immunotherapy) eg venom
Self-administered epinephrine
What is meant by obstructive sleep apnoea?
- Intermittent upper airway collapse in sleep
- causes patient to stop breathing for short period (apnoea)
- patient often wakes up => fragmented sleep
What are the risk factors for sleep apnoea?
- Enlarged tonsils, adenoids OR Oropharyngeal deformity
- Obesity
- Acromegaly, hypothyroidism
- Neurological muscle problem
- Sedative Drugs: benzos, opiates, alcohol,
- Post-op. after anaesthesia
What consequences can sleep apnoea cause in a person’s daily life?
- excessive daytime sleepiness
=> driving impaired - personality change
- cognitive / functional impairment
What other medical conditions are a potential consequence of sleep apnoea?
- risk factor for hypertension (due to activating sympathetic system)
=> increased risk of stroke and cardiovascular events - Raised CRP
- Impaired endothelial function
- Impaired glucose tolerance
Consequences of Sleep Apnoea are all improved by what type of ventilation?
CPAP
What symptoms would raise a person’s Epworth Score and point towards a diagnosis of Sleep Apnoea?
- snoring
- excessive daytime sleepiness
What investigations can be used to diagnose sleep apnoea?
- Overnight sleep study
=> oximetry
=> domicillary recording (airflow, oximetry, thoracic/abdominal movement)
How is obstructive sleep apnoea treated?
- Remove underlying cause
- CPAP (continuous positive airway pressure)
=> patient wears mask over nose as they sleep
What can be used to improve snoring for a patient?
Mandibular Advancement Device
- improves snoring
AND improves apnoea-hypoapnoea index
