Otitis 2 Flashcards
What are benefits of ear cleaning with otitis?
- Removal of infectious debris & disruption of microbial biofilms
- Visualisation of TM
- Assess epithelium: hyperplasia, ulceration, defects
- Expose and/or sample otic polyps/tumours
- Enhance action of topical therapy
What do ear cleaning methods depend on?
- Severity of otitis (stenosis, pain)
- Type and volume of discharge
- Client factors e.g. finances
- Patient factors e.g. Tympanic Membrane rupture
What are drugs with Potential to cause deafness and/or
vestibular signs if applied to middle ear?
- Polymixin B
- Ticarcillin
- Imipenem
- Gentamicin (mainly an issue with systemically use)
- Propylene glycol (very low concentrations seem to be tolerated)
- Alcohols e.g. isopropyl
- Acids e.g. salicylic
- Chlorhexidine >0.15% (dogs; never use in cats)
- Injectables that can’t be given IV
What are Drugs that may enhance effect of potentially ototoxic treatments?
- Frusemide and other loop diuretics
- Cisplatin
- Erythromycin
- NSAIDs
What is a biofilm? How is it treated?
- Microbes stuck together in extracellular matrix
- Protected environment, infection difficult to treat
- N-acetylcysteine, Betaine/polyhexanide
- Disrupt biofilm and reduce viability of Staphylococcus
spp. and Pseudomonas spp.
– Sterile water/saline lavage, instill product, massage (< 5 mins)
– Remove by suction, thoroughly lavage with sterile saline
Why would you use anti-inflammatories? What would you use?
- Resolve progressive pathological change - epithelial + glandular hyperplasia + stenosis
- Glucocorticoids = anti-pruritic, decreased glandular secretions, exudation, scar tissue + proliferative changes
= Systemic / topical prednisolone
What is different when doing cytology sampling of external ear canal and middle ear?
- EEC = indirect smear using cotton bud
- Middle ear = otoscopic guidance, urinary catheter + suction using syringe then spray onto slide
How do you select topical antimicrobials?
- On cytology - no microbial overgrowth = anti-inflammatories
- yeast = topical antiseptic/antifungals
- bacteria = topical antiseptics/antibiotics
What is spectrum of activity of different ear treatments?
- Chlorhexidine = G+ve cocci, G-ve rods, Malassezia
- Fucidic acid, framycetin, florfenicol = G+ve cocci
- Polymixin B, marbofloxacin, gentamicin = G+ve cocci,
G-ve rods - Clotrimazole, miconazole, nystatin = Malassezia
What is proprietary topical antimicrobials?
- Use of combination of cerumenolytics, antiseptics, antibiotics, antifungals + corticosteroids
= NOT LICENCED if ruptured eardrum - Potential for ototoxicity
What should be done for treatment if you can’t see the eardrum?
- No treatment licenced for use with ruptured tympanic membrane =
- Treat 1-2 wks with systemic prednisolone & recheck
- Clean ear (ideally GA) & recheck
- Treat with ‘safe’ water-based product & recheck
What could you use to treat pseudomonas?
- Active against G-ve rods + safe =
- silver sulfadiazine
- enrofloxacin
- marbofloxacin
What would you use to treat hypersensitivity otitis?
- Recicort - triamcinolone (licenced for 7 days)
- Dexadresson (dexamethasone)
- Cortavance (HCA)
- need to treat allergic inflammation to prevent recurrence
What is long term treatment of ear problems?
- Ear cleaning - Otoact - weekly
- Anti-inflammatory - HCA - cortavance (on skin lesions + ears twice weekly)
- Skin barrier = EFAs in FOOD - daily
- Allergen specific immunotherapy
What can otitis lead to?
- Solid, non-pliable EEC on external palpation
- Severe stenosis and fibrosis on otoscopy
- Marked mineralisation of ear canals and/ or osteomyelitis on diagnostic imaging
- Neoplasia/polyps
- Cholesteatoma
- Para-aural abscessation
