DOHNS MCQs Flashcards
What organism is most commonly involved in peri-orbital cellulitis (i.e. child)
Streptococcus spp
What should be assessed in the eye examination of a peri-orbital cellulitis patient
Colour (discrimination) vision, pupillary reflex, visual acuity, proptosis, pain on eye movements and presence of ophthalmoplegia & diplopia
What imaging is important in a patient presenting with suspected peri-orbital cellulitis? (Be specific with the views if possible)
CT imaging of the brain, nose and paranasal sinuses/orbit with contrast.
Axial sections through the orbit to check for an abscess
What is the name of the grading system for peri-orbital cellulitis? List them.
Chandler’s grading system
1 = pre-septal cellulitis = Eyelid (anterior to tarsal plate) swelling without proptosis, ophthalmoplegia or loss of vision.
2 = Orbital cellulitis without abscess = cellulitis involving the orbit including post-septal tissues.
3 = Orbital cellulitis with subperiosteal abscess - cellulitis with abscess confined to the orbital periosteum (between ethmoid sinus and medial orbital wall). Most common medially @ the lamina papyracea which causes lateral displacement of the middle rectus muscle.
IV. Intra-orbital abscess - an abscess in the intraconal compartment (behind the globe between the extra-ocular muscles)
V. Cavernous sinus thrombosis - BILATERAL periorbital swelling with proptosis, ophthalmoplegia and neurological signs.
What is the management option for peri-orbital cellulitis?
Medical (if no abscess) = Broad-spectrum IV antibiotic (co-amoxiclav) + nasal decongestants + nasal steroids + nasal douches + IV fluids + analgesia
Surgical (if abscess) = Drainage via OPEN approach using modified Lynch Howarth incision or ENDOSCOPIC drainage by removing the partially dehiscent lamina papyracea (ethmoidectomy)
Name 6 complications associated with surgical intervention for peri-orbital cellulitis.
Immediate: Damage to orbital structures leading to bleeding and blindness.
Early: Diplopia or progressive swelling.
24 hours post-op: Disease recurrence/residual +- intracranial sepsis +- abscess formation
Late: Diplopia +- decreased acuity +- scarring +- enopthalmos.
What is the common pathophysiology of peri-orbital cellulitis?
Common in kids around age 3.5 years old.
Acute rhinosinusitis which spreads to the orbit via ethmoid sinus through the dehisced lamina papyracea.
What is the pathology of blindness in peri-orbital cellulitis?
Stretching of the intraorbital optic nerve and ischaemia.
How do you manage a child with foreign body in A&E?
APLS protocol. High flow oxygen + nebulised adrenaline and heliox + call senior (ENT paeds anaesthetist) immediately.
List 3 differentials for children presenting with respiratory distress.
Congenital: laryngomalacia
Traumatic: vocal cord palsy, subglottic stenosis
Infection: adenotonsilitis, epiglottitis, laryngotracheobronchitis (croup)
What imaging would you order for inhaled/ingested foreign body?
AP and lateral view xray of chest and neck.
What instruments will you request to manage inhaled foreign body?
Rigid ventilating bronchoscope and optical forceps
List 3 potential complications associated with FB retrieval via bronchoscopy?
- Bleeding
- Tracheobronchial perforation
- Failure of removal
- Dental injury
- Hoarse voice due to trauma to vocal folds.
Which bronchus is more likely to have FB in it and why?
Right bronchus as it is less angled than the left.
What is the ball-valve effect?
Bronchi dilating slightly during inspiration, and subsequent constriction due to increased intrathoracic pressure during expiration. This progressive air trapping (hyperinflated lung) and mediastinal shift.
