Microsuction for Otitis Externa: When and How It's Used

Key Takeaways:

• Otitis externa affects approximately 1 in 10 people at some point in their lives, with the ear canal becoming inflamed, swollen, and often filled with debris
• Aural toilet — the removal of debris, discharge, and dead skin from the ear canal — is a critical step that allows topical antibiotic and antifungal drops to reach the infected tissue
• Microsuction is the preferred method of aural toilet because it avoids water introduction, provides direct visualisation, and allows precise, controlled clearance
• Clinicians must take extra care with noise levels, suction pressure, and probe selection when treating inflamed ear canals

What Is Otitis Externa?

Otitis externa is an infection or inflammation of the external ear canal — the passage between the outer ear and the eardrum. It is commonly known as swimmer’s ear because water exposure is a frequent trigger, though it can occur without any swimming at all.

The condition presents with pain (often severe), itching, discharge, and conductive hearing loss. The ear canal may be visibly swollen and narrowed, and the skin is typically red, oedematous, and tender to touch.

Prevalence and Causes

Otitis externa is one of the most common ear conditions seen in primary and secondary care:

• Lifetime prevalence: Approximately 10% of the population
• Peak incidence: Summer months (increased water exposure) and in tropical climates
• Recurrence: Up to 25% of patients experience repeated episodes

Common Causes

• Bacterial infection — Pseudomonas aeruginosa and Staphylococcus aureus are the most frequent pathogens
• Fungal infection — Aspergillus and Candida species, particularly in chronic or recurrent cases
• Water exposure — Swimming, bathing, or humid environments that macerate canal skin
• Trauma — Cotton buds, hearing aids, or scratching that damages the protective skin barrier
• Skin conditions — Eczema, psoriasis, and seborrhoeic dermatitis predispose to infection
• Ear wax removal — Paradoxically, over-cleaning the ear canal removes the protective cerumen layer

Why Aural Toilet Is Essential

When the ear canal is filled with debris, discharge, and desquamated skin, topical treatments cannot reach the infected tissue. Studies have shown that topical antibiotic drops are significantly less effective when applied to a canal that has not been cleared. This is why aural toilet — the systematic removal of debris — is considered a crucial first step in managing moderate-to-severe otitis externa.

Without aural toilet:

• Drops pool on top of debris rather than contacting the canal wall
• The moist, enclosed environment encourages further microbial growth
• Debris acts as a reservoir for reinfection
• The clinician cannot adequately visualise the eardrum to exclude more serious pathology (such as perforation or cholesteatoma)

Why Microsuction Is Preferred

Microsuction is the method of choice for aural toilet in otitis externa for several important reasons:

No Water Introduction

Unlike irrigation, microsuction does not introduce water into an already compromised ear canal. Water would worsen maceration, dilute topical treatments, and increase the risk of secondary infection.

Direct Visualisation

The clinician works under a binocular microscope or loupes, seeing exactly what they are removing. This is critical in an inflamed canal where the anatomy may be distorted and the eardrum may be obscured.

Controlled Precision

Fingertip suction control allows the clinician to adjust pressure in real time. In an inflamed canal, the skin is fragile and oedematous — excessive suction can cause pain, bleeding, and further trauma.

Specimen Collection

If a swab for microbiology is needed, the clinician can take it under direct vision before clearing the canal, ensuring an accurate culture result.

Technique Considerations for Infected Ears

Performing microsuction on an infected ear requires modification of the standard technique:

Suction Pressure

• Reduce pressure significantly below normal working levels — inflamed skin is fragile and bleeds easily
• Use the minimum suction necessary to clear debris
• Fingertip control is essential; on/off suction units without variable pressure are poorly suited to this task

Probe Selection

• Use a wider bore probe (2–3 mm) where the canal allows, to reduce focal suction force
• Avoid probes that are too narrow for the debris type — this increases the risk of blocking and requires repeated passes

Noise Considerations

An inflamed ear canal is more sensitive to noise. The suction sound is conducted through the canal walls and can be distressing for the patient.

• Use the quietest device available — units operating at 75 dB or below are significantly more comfortable than traditional devices
• Devices such as the Zephyr, which are silent when idle, reduce cumulative noise exposure during pauses
• Warn the patient before activating suction, and take regular breaks

Patient Comfort

• Administer topical anaesthesia (such as lidocaine spray) if the canal is extremely tender
• Work slowly and gently — rushing increases pain and the risk of complications
• Communicate continuously with the patient and stop immediately if they report sharp pain

Contraindications and Caution

Microsuction for otitis externa should be performed with caution or deferred in the following situations:

• Necrotising (malignant) otitis externa — A life-threatening condition seen in immunocompromised or diabetic patients. Urgent ENT referral is required
• Suspected tympanic membrane perforation — Avoid suction near the eardrum until the full extent of the perforation is visualised
• Severe canal stenosis — If the canal is too swollen to admit a probe safely, a wick soaked in antibiotic/steroid drops may be placed first, with microsuction rescheduled after 48–72 hours of treatment
• Uncooperative patient — Particularly in children, where sudden movement during suction could cause injury

When to Refer to ENT

Refer to an ENT specialist if:

• Symptoms do not improve after two weeks of appropriate treatment
• You suspect necrotising otitis externa (severe pain, granulation tissue, exposed bone)
• There is recurrent otitis externa (four or more episodes per year)
• You cannot adequately visualise the eardrum after aural toilet
• The patient is immunocompromised or has poorly controlled diabetes
• You identify unexpected pathology during the procedure (cholesteatoma, polyp, or tumour)

Microsuction is an invaluable tool in the management of otitis externa. When performed carefully, with appropriate equipment and technique, it significantly improves treatment outcomes by ensuring topical therapy can reach the affected tissue. For clinicians, understanding the safety profile of microsuction and adapting technique for inflamed canals is essential.