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Meta-Analysis
. 2020 Sep 14;9(9):CD013057.
doi: 10.1002/14651858.CD013057.pub2.

Aural toilet (ear cleaning) for chronic suppurative otitis media

Mahmood F Bhutta  1 , Karen Head  2 , Lee-Yee Chong  3 , Jessica Daw  4 , Anne Gm Schilder  5 , Martin J Burton  6 , Christopher G Brennan-Jones  4
Affiliations
Meta-Analysis

Aural toilet (ear cleaning) for chronic suppurative otitis media

Mahmood F Bhutta et al. Cochrane Database Syst Rev. .

Update in

Abstract

Background: Chronic suppurative otitis media (CSOM), sometimes referred to as chronic otitis media (COM), is a chronic inflammation and often polymicrobial infection (involving more than one micro-organism) of the middle ear and mastoid cavity, characterised by ear discharge (otorrhoea) through a perforated tympanic membrane. The predominant symptoms of CSOM are ear discharge and hearing loss. Aural toileting is a term describing a number of processes for manually cleaning the ear. Techniques used may include dry mopping (with cotton wool or tissue paper), suction clearance (typically under a microscope) or irrigation (using manual or automated syringing). Dry mopping may be effective in removing mucopurulent discharge. Compared to irrigation or microsuction it is less effective in removing epithelial debris or thick pus. Aural toileting can be used alone or in addition to other treatments for CSOM, such as antibiotics or topical antiseptics.

Objectives: To assess the effects of aural toilet procedures for people with CSOM.

Search methods: The Cochrane ENT Information Specialist searched the Cochrane ENT Register; Central Register of Controlled Trials (CENTRAL via the Cochrane Register of Studies); Ovid MEDLINE; Ovid Embase; CINAHL; Web of Science; ClinicalTrials.gov; ICTRP and additional sources for published and unpublished trials. The date of the search was 16 March 2020.

Selection criteria: We included randomised controlled trials (RCTs) with at least a one-week follow-up involving people (adults and children) who had chronic ear discharge of unknown cause or CSOM, where the ear discharge had continued for more than two weeks. We included any aural toileting method as the intervention, at any frequency and for any duration. The comparisons were aural toileting compared with a) placebo or no intervention, and b) any other aural toileting method. We analysed trials in which background treatments were used in both arms (e.g. topical antiseptics or topical antibiotics) separately.

Data collection and analysis: We used the standard Cochrane methodological procedures. We used GRADE to assess the certainty of the evidence for each outcome. Our primary outcomes were: resolution of ear discharge or 'dry ear' (whether otoscopically confirmed or not), measured at between one week and up to two weeks, two weeks to up to four weeks, and after four weeks; health-related quality of life using a validated instrument; and ear pain (otalgia) or discomfort or local irritation. Secondary outcomes were hearing, serious complications, and the adverse events of ear bleeding and dizziness/vertigo/balance problems.

Main results: We included three studies with a total of 431 participants (465 ears), reporting on two comparisons. Two studies included only children with CSOM in the community (351 participants) and the other study (80 participants) included children and adults with chronic ear discharge for at least six weeks. None of the included studies reported the outcomes of health-related quality of life, ear pain or the adverse event of ear bleeding. Daily aural toileting (dry mopping) versus no treatment Two studies (351 children; 370 ears) compared daily dry mopping with no treatment. Neither study presented results for resolution of ear discharge at between one and up to two weeks or between two to four weeks. For resolution of ear discharge after four weeks, one study reported the results per person. We are very uncertain whether there is a difference at 16 weeks (risk ratio (RR) 1.01, 95% confidence interval (CI) 0.60 to 1.72; 1 study; 217 participants) because the certainty of the evidence is very low. No results were reported for the adverse events of dizziness, vertigo or balance problems. Only one study reported serious complications, but it was not clear which group these patients were from, or whether the complications occurred pre- or post-treatment. One study reported hearing, but the results were presented by treatment outcome rather than by treatment group so it is not possible to determine whether there is a difference between the two groups. Daily aural toileting versus single aural toileting on top of topical ciprofloxacin One study (80 participants; 95 ears) compared daily aural toileting (suction) with administration of topical antibiotic (ciprofloxacin) ear drops in a clinic, to a single aural toileting (suction) episode followed by daily self-administered topical antibiotic drops, in participants of all ages. We are unsure whether there is a difference in resolution of ear discharge at between one and up to two weeks (RR 1.09, 95% CI 0.91 to 1.30; 1 study; 80 participants) because the certainty of the evidence is very low. There were no results reported for resolution of ear discharge at between two to four weeks. The results for resolution of ear discharge after four weeks were presented by ear, not person, and could not be adjusted to by person. One patient in the group with single aural toileting and self administration of topical antibiotic ear drops reported the adverse event of dizziness, which the authors attributed to the use of cold topical ciprofloxacin. It is very uncertain whether there is a difference between the groups (RR 0.33, 95% CI 0.01 to 7.95; 1 study; 80 participants, very low-certainty). No results were reported for the other adverse events of vertigo or balance problems, or for serious complications. The authors only reported qualitatively that there was no difference between the two groups in hearing results (very low-certainty).

Authors' conclusions: We are very uncertain whether or not treatment with aural toileting is effective in resolving ear discharge in people with CSOM, due to a lack of data and the poor quality of the available evidence. We also remain uncertain about other outcomes, including adverse events, as these were not well reported. Similarly, we are very uncertain whether daily suction clearance, followed by antibiotic ear drops administered at a clinic, is better than a single episode of suction clearance followed by self-administration of topical antibiotic ear drops.

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Conflict of interest statement

Mahmood F Bhutta: Professor Mahmood Bhutta has received an honorarium from Novus Therapeutics for advice on an experimental treatment for otitis media (not related to any treatment in this review).

Karen Head: none known.

Lee Yee Chong: none known.

Jessica Daw: none known.

Anne GM Schilder: Professor Anne Schilder was until March 2020 the joint Co‐ordinating Editor of Cochrane ENT, but had no role in the editorial process for this review. Her evidENT team at UCL is supported in part by the National Institute of Health Research (NIHR) University College London Hospitals Biomedical Research Centre. The research is funded by the NIHR and EU Horizon2020. She is the national chair of the NIHR Clinical Research Network ENT Specialty. She is the Surgical Specialty Lead for ENT for the Royal College of Surgeons of England's Clinical Trials Initiative. In her role as director of the NIHR UCLH BRC Deafness and Hearing Problems Theme, she acts as an advisor on clinical trial design and delivery to a range of biotech companies, most currently Novus Therapeutics.

Martin J Burton: Professor Martin Burton is joint Co‐ordinating Editor of Cochrane ENT, but had no role in the editorial process for this review.

Christopher G Brennan‐Jones: Dr Brennan‐Jones's research team is primarily funded by the Australian NHMRC and the WA Department of Health. He sits on the national Technical Advisory Group responsible for developing treatment guidelines for otitis media in Australia.

Figures

1
1
Process for sifting search results and selecting studies for inclusion.
2
2
'Risk of bias' graph: review authors' judgements about each risk of bias item presented as percentages across all included studies.
3
3
'Risk of bias' summary: review authors' judgements about each risk of bias item for each included study.
1.1
1.1. Analysis
Comparison 1: Aural toileting versus no aural toileting, Outcome 1: Resolution of ear discharge (4 weeks +)
2.1
2.1. Analysis
Comparison 2: Daily aural toileting versus single aural toileting, Outcome 1: Resolution of ear discharge (1 to 2 weeks)
2.2
2.2. Analysis
Comparison 2: Daily aural toileting versus single aural toileting, Outcome 2: Vertigo/dizziness/tinnitus
See this image and copyright information in PMC

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