ENT Flashcards
What are the sinuses responsible for?
Immune defence/air filtration through their mucus production.
- Ciliated nasal & sinal mucosae move mucus
- Nasal mucus traps bacteria and small particles
Describe nasal congestion.
- Excess nasal secretions
- Inflamed & swollen nasal mucosa
Causes: allergies & URT infections
What do histamine receptors do?
Mediator of allergic/ inflammatory reaction
Where are H1 receptors found and what is their function?
Smooth muscle, respiratory epithelium, endothelial cells, bronchial smooth muscle cells
F: vasodilation, bronchoconstriction, mucus secretion
Where are H2 receptors found and what is their function?
Gastric parietal cells
F: gastric acid secretion
Where are H3 receptors found and what is their function?
CNS
F: sleep/wake, cognition, neurotransmission
Where are H4 receptors found and what is their function?
Immune cells
F: immune response modulation
Describe the effects of histamine on the smooth muscle.
- Bronchial SM H1-R activation induces bronchoconstriction due to increases Ca 2+.
- Coupled to G-protein
- Activation causes increased Ca2+ leading to release of mediators
- Vascular SM H1-R activation induces vasodilation
- Relaxation of vascular SM & vasodilation increase BF and leakage from vessels into surrounding tissue leading to swelling.
- Irritation of airways and sinuses triggers mucus production which fills the sinuses.
What is the MOA of decongestants?
alpha1-R agonists - bind to receptors in URT triggering vasoconstriction
What are the two types of decongestants?
Adrenergics - largest group of sympathomimetics
Anticholinergics - less commonly used parasympatholytics
Oral decongestants
Adrenergic
- Prolonged effects but delayed onset
- Less potent than topical
- No rebound congestion
E.g. - pseudoephedrine, phenylephrine, ephedrine
What are the side effects of oral decongestants?
headaches
insomnia
dry mouth
What is the MOA of oral decongestants?
Bind to alpha1-R in URT and alpha1-R in blood vessels and some affinity for B-R in cardiac muscle - not suitable for patients with heart conditions
Topical decongestants
Adrenergic
- Constrict small blood vessels supplying URT
- Tissues shrink to open nasal passages - nasal secretion drain
- Relieves nasal stuffiness
- Prompt onset and optent effect
- Sustained use over several days causes rebound congestion
E.g. - oxymetazoline, xylometazoline
What are the side effects of topical decongestants?
CV effects
nasal dryness
headache/nausea
What are nasal steroids used for and what are some examples?
- Mainly used for allergies/hay fever for up to 3months
- Turn off immune cells, having an anti inflammatory response which leads to decreased congestion which relieves nasal stuffiness.
E.g. Beclometasone dipropionate, fluticasone
What are the side effects of nasal decongestants?
Nasal dryness and irritation
What is otitis media?
Middle ear inflammation between tympanic membrane & inner ear. Often follows URT symptoms e.g. cough
How does otitis media occur?
The middle of the ear becomes infected, pressure builds up behind eardrum causing intense pain, fever and hearing loss
What is suppurative otitis media?
Perforated tympanic membrane - otorrhoea (fluid discharge)
What is the treatment for otitis media?
1st line - analgesics e.g. paracetamol, ibuprofen
2nd line - antibiotics in some cases but not preferred
What is Glue Ear?
Chronic otitis media - inflammation of middle ear and accumulation of fluid blocking the eustachian tube
- hearing loss
- common in kids
- spontaneous resolution in 3months-1 year
What is otitis externa? treatment?
Swimmers ear - inflammation of outer ear and ear canal
Treatment: dilute acetic acid e.g. earcalm and steroid drops and antibacterial drops (POM)
What are the types of sore throat?
Pharyngitis/ acute tonsillitis
- bacterial or viral infection
- headache, muscle aches, cough, dysphagia
- Inflammation - redness & swelling
Describe strep throat and its treatment.
Rapid strep test - swab throat and test
- if group a sterp treat with penicillin
Treatment: lozenges/ throat spray - menthol/local anaesthetics e.g. lidocaine.
When should patients be. referred?
- Recurrent sore throats
- No improvement of symptoms after 2 weeks
- Persistent high temp above 38 degree not decrease by medication.
- Can develop into more serious infection
