Stridor and Sleep Apnoea Flashcards
What is stridor?
Predominantly inspiratory wheeze due to large airway, (larynx, trachea or major bronchi) obstruction
What are the most common extrathoracic causes of stridor?
Laryngomalacia- congentital softening of the soft tissues of the larynx
Supraglottic mass- a mass above the glottis
Glotic lesions
Vocal chord paralysis (only if bilateral as the body will compensate for unilateral paralysis)
What are the most common causes of stridor in children?
Croup Epigolttisis (H. influenzae medical emergency) Pseudomembranous croups Reteropharangeal abcess Dipthiria Glandular fever Foreign body Anaphlyaxis Burns- inhaled hot vapour causing oedema and traumatic insult to upper airway
Which bronchi is a foreign body more likely to be found in?
Right bronchi as it’s more vertical than the left
What are the signs of foreign body inhalation in children and older people at high risk?
Acute onset of stridor accompanied by a chocking spell
Children’s cough reflex is not as good as adults
What are the most common causes of stridor in adults?
Neoplasms in the larynx, trachea and major bronchi
Anaphylaxis
Goitre- enlarged thyroid
Trauma- burns strangulation or irrritant gases
Bilateral vocal chord palsy
Wenger’s granulomatous- inflamatory problem
Cricoarytenoid arthritis
Tracheopathia
Tracheomalacia
What is Tracheomalacia?
Tracheomalacia- Flaccidity of the supporting tracheal cartilage, widening of the posterior membranous wall and reduced anterior-posterior airway calibre => airway collapse during times of increase air flow
What is Tracheopathia?
Tracheopathia- benign endoluminal projection of cartilaginous and bony nodules arising in the sub mucosa
If smeone presents with stridor, what investigations are needed?
Laryngoscopy- beware acute epiglotitis as will irritate airway more
Bronchoscopy
Siprometry
CXR ?CT and ?thyroid scan
What will spirometry show with an upper airway obstruction?
Low peak flow but continues for a longer period of time before dropping off- like a table top mountain
What is the treatment for laryngeal obstruction?
Treat underlying cause- remove forign body etc
Mask bag ventilation with high flow oxygen
Cricothyroidotomy if the airway is entirely blocked
Tracheotomy- surgical incission in the neck and trachea
What is the treatment for malignant airway obstruction?
Tumour removal using: Laser/photodynamic therapy Crycotherapy- freezing technique Diathermy- electrical induced heat/electromagnetic current Surgical resection Tumour compression using intraluminal stent Radiotherapy/Bracheotherapy Chemotherapy
What is acute anaphylaxis?
Type 1 sensitivity reaction- IgE mediated
Occurs when someone is already sensitised to the antigen and mast cells are already present and immediately degranulate causing inflammation and oedema
What are the signs of anaphylaxis?
Flushing, urticaria (Hives), Pruritus (severe itching of the skin)
Angioneurotic oedema (Lips, tongue, face, larynx, bronchi)
Abdominal pain and vommiting
Hypotention (casodilation and plasma exudation => shock)
Stridor, wheeze and respiratory failure
What are the most common causes of anaphylaxis?
Foods, insect venom, drugs and latex
What is the treatment for anaphylaxis?
5 micrograms of IM adrenaline-effect immediate
IV antihistamine- effect 15-20 mins
IV steriods (hydrocortisone or prednisalone)- effect hours
High flow oxygen
Nebulised bronchiodilators
Endotracheal intubation if necessary
What are the important counselling points to give someone with a severe allergic reaction?
Allegen avoidance
Desensitisation (immunotherapy- give small doses of antigen weekly to build up a tolerance)
Epipen use- self administered adrenaline
What does the epworth score assess and what is a normal score?
Sleepiness and a normal score is <10/24
8 questions scoring up to 3 for each
What causes snoring?
Relaxation of pharyngeal dilator muscles during sleep, especially REM sleep => upper airway narrowing, turbulent airflow and vibration of soft palate and tongue base
What is OSA?
Intermittant upper airway collapse in sleep
Apnoesa or hypoapnoeas +/- hypoxaemia which lead to recurrent arousals
What are the consequences of OSA?
1) Sleep fragmentation. Normal people wake 30 times a night. OSA patients wake >100 times a night
2) Excessive daytime sleepiness
3) Personality change
4) Cognative/functional impairment due to differential oxygen flow to the brain
5) probable increase in CVD and CVA
When do children get OSA?
Enlarged or infected tonsils
What proportion of the adult population is affected by OSA?
1-4%
What are the risk factors for OSA?
Obesity
Enlarged tonsils/adenoids (tissue at back of nose)
Retronathia- jaw set back
Acromegaly (excess growth hormone)/ Hypothyroidism
Neurological- anything that effects muscle tone
Drugs- benzodiazepines, opiates, alcohol
Post Op after anaesthesia
Waking up regularly increases sympathetic stimulation which has multiple effects on the body. How does this effect:
1) C reactive protein
2) blood pressure
3) glucose tolerance
1) C reactive protein- raised => more inflamation
2) blood pressure- raised => OSA is an independant risk factor for hypertention
3) glucose tolerance- impaired => diabetes
How is OSA diagnosed?
1) Snoring and excessive daytime sleepiness- high epworth score
2) Overnight sleep study including oximetry, domicillary recording (airflow oximetry and thoracic/abdominal movements
How is OSA treated?
1) Remove underlying cause- for most people there is none
2) CPAP- continuous positive airway pressure
3) Mandibular advancement device
4) Surgery- uncommon
What is CPAP?
Continuous positive airway pressure
Most effective and greatest increase in QoL
Uses a full face mask and helps to keep upper airways patent
What is a mandibular advancement device?
Brings the jaw forward and tries to open the airway at the back
Improves snoring and good for mild cases/claustrophobia
