Otitis 2 Flashcards
Evaluate the use of povidone iodine as an otic flushing solution
- Recommended by some but others state ototoxicity
- May be useful if Proteus is present
Evaluate the use of saline as an otic flushing solution
Safe, widely available, sterile
Evaluate the use of chlorhexidine as an otic flushing solution
- Problematic at higher concentrations
- 0.15% safe in dogs but not cats
- Use TRIZChlor flush only, any higher concentration is ototoxic
When should cerumolytics, aqueous solutions and drying agents be used as flushing solutions?
Only when the drum is known to be in tact
Evaluate the use of cerumolytics as an otic flushing solution and give examples
To emulsify ear wax for easy removal, e.g. squalene, alcohols
Evaluate the use of aqueous solutions as an otic flushing solution
Aid in removal of pus, mucus and serum from the ears
Evaluate the use of drying agents as an otic flushing solution and give an example
Decrease moisture in ears and dessicate the surface keratinocytes, e.g. boric acid
Outline the anaesthetic requirement during ear flushing
- Required in severe/chronic cases
- ET tube protects from aspiration of flushing solution via eustachian tube
- Hearing often present even with sedation
- Allows adequate assessment of the ear, especially if painful
Outline the disadvantages and advantages of the manual otoscope and syringe method for ear flushing
- Spreul needle used, but reusable and often damaged with sharp edges, disposable better
- Cut down gauge 6 urinary catheter
- Large catheter cover
- Precise but time consuming
- can make ear sore through rubbing of speculum, premed with steroids at least one day before
- Equipment inexpensive
Outline the disadvantages and advantages of the video otoscopy method for ear flushing
- Precise
- Able to record data if data capture technique
- Custom made curettes, biopsy and grabbing tools available
- Small bore channel means slow cleaning in some cases
- May not fit the smallest ears
What are the aims of otitis treatment?
- Remove/reduce microbes
- Reduce swelling, discomfort or pain
- Normalise canal lumen and function
Give a key advantage and disadvantage of Aurizon ear treatment
- Broad spectrum
- But poor for diabetics
Give a key advantage and disadvantage of Easotic ear treatment
- Better for diabetics
- Poorly absorbed steroids
Give the key advantages and disadvantages of Osurnia ear treatment
Advantages:
- Good for incompetent owner or very painful dog
- Good anti-staph and anti-malassezia treatment
- First line treatment
Disadvantages
- Poor for Pseudomonas
- Poor for progressive disease
What is the main issue with all ear treatments?
All state not for use if ear drum not intact, but difficult to assess so need to go off license or avoid ototoxic drugs
List drugs which are ototoxic
- Gentamicin
- Polymyxin B
- Ticarcillin and imipene
- Propylene glycol
- Chlorhexidine at moderate concentrations
Outline a basic treatment for acute otitis
- Use first line ointment with antimicrobial, steroid and antifungal based on cytology and otoscopy
- Once to twice daily for 7-14 days
- Ensure use of sufficient amount )0.7-1ml for large dog)
- Combine with suitable cleaner e.g. TRIXChlor, Cleanaural, Malacetic otic
When presented with ear disease with a great deal of discharge and unclear time course, what would be a logical approach?
- Admit for flush etc., treat as chronic case
- Cannot be confident that disease has not been there for a while
List cytological indications for bacterial culture in otitis
- Rods seen, need suitable antibiotic
- Marked purulent discharge without organisms noted
- Pyogranulomatous inflammation
Why is bacterial culture recommended in a case of otitis with pyogranulomatous inflammation?
- Organisms difficult to see with cytology in this uncommon ear inflammation
- Culture obligatory
- Basement membrane breached, ulcerated ears
List the clinical infications for bacterial culture in otitis
- In the event of treatment failure
- If there is a suspicion of MRSP, MRSA, MRSS
- If considering video otoscopy or ear flush for diagnosis, or treatment in a bacterial otitis
Why is bacterial culture recommended in a case where video otoscopy is to be used?
Risk of adverse event following these procedures e.g. neurological signs meaning that systemic antimicrobials may be required
When should an ear with otitis be re-checked?
Obligatory 7-10 days recheck
What should be assessed at the re-check for otitis?
- Improvement?
- Asses owner compliance
- Identification of next stage of treatment
- May need to restore epithelial migration
- Identificaiton of underlying cause
Outline the treatment recommended for teh treatment of chronic allergy leading to otitis
- Avoid use of antibiotics
- Control microflora through cleaning
- Use topical steroids to control inflammation
- Lokivetmab and oclacitanib are poor for ear disease, will commonly need a treatment for the body and a treatment for the ear
What is the importance of Pseumonas otitis?
Common cause of otitis - 35% of OE and/or OM and aggressive treatment required
What is Pseudomonas otitis commonly associated with?
- Poorly managed or untreated Malassezia or Staphylococcal otitis
- Immunosuppression
- Swimming
- Prior use of antibacterials
Describe the appearance of Pseudomonas otitis
- Swelling, pain, malodour common
- Often ulcerated
- Green to browny-black discharge
Outline the plan for Pseudomonas otitis with severe disease
- Always flush if purulent material
- Presume drum ruptured as a result of collagenase produced by bacteria
- Presume OM and likelihood of OI
- Warn owner of risks of flushing, treatment and disease itself e.g. Horner’s, facial paralysis, hearing loss
- Possibly TECA
- Use of non-licensed products e.g. OE medication such as Aurizon
- Bacteriology, flush and clean, disinfectant cleaner e.g. TRIZChlor, apply suitable antibiotic, provide anti-inflamm and analgesia
Outline a treatment plan for a dog with Pseudomonas otitis that has received little previous treatment
- Cleaning with saline
- Disinfect with TRIZChlor 10 minute soak
- Aurizon antibiotic
- Introperative opiod analgesia e.g. morphine
- Dexamethasone 0.3mg/kg IV at end of procedure
- Home on Aurizon ear cream 0.4-0.7ml BID for 7 days, TRIZChlor SID starting on day 4, prednisolone 0.5mg/kg SID PO
- Reassess at 7 days
- If doing well and marked chronic changes, increase dose of steroids, consider reducing frequency of drops and cleaner
Outline a treatment plan for a dog with Pseudomonas otitis that has been identified as a multi-resistant organism
- Cleaning with saline, disinfect with TRIZChlor 10 min soak
- Silver sulfadiazine antibiotic
- Intraoperative morphine, dexamethasone 0.2mg/kg IV at end of procedure
- Home on TRIZChlor BID, silver sulfadiazine 1:9 aqueous soln at least BID to fill ear (OR gentamicin, ticarcillin if suitable susceptibility data), pred 0.5mg/kg SID PO, pain relief
- Reassess at 5 days to allow complete flushing and disinfection
- Further otoscopy/fushing as needed
What can ear canal stenosis be a consequence of?
- Chronic low grade trauma
- Severe acute disease untreated
- Trauma
- Mcuinosis +/- confirmation in shar Pei
What are the potential approaches to a stenotic ear?
- Potent topical steroids
- Oral steroids (pred 1-2mg/kg PO)
- Tacrolimus 0.1% ointment
- Intralesional steroids
- Treatment can be concurrent with, or if inappropriate after infection control
Outline the use of potent topical steroids in the treatment of otic stenosis
- Commercial medications for extended course e.g. Easotic, Posatex, Aurizon
- Beware local and systemic steroid side effects esp. in small dogs
- Long periods of treatment needed
Outline the use of tacrolimus 0.1% ointment (topical ciclosporin) in the treatment of otic stenosis
Applied to ear twice daily with care (gloves)