Review question
This review compares the effects and safety of interventions in children with grommets who develop ear discharge beyond the immediate postoperative period.
Background
The insertion of grommets (1 to 2 mm plastic tubes placed into the eardrum) is one of the commonest surgical procedures performed in children worldwide. Up to three in four children with grommets develop episodes of ear discharge. When this occurs beyond the immediate postoperative period, it is thought to be a symptom of a middle ear infection. The most common treatments include oral antibiotics (i.e. by mouth), antibiotic eardrops or those containing a combination of antibiotic(s) and a corticosteroid, and initial observation. Important reasons for physicians to choose one treatment over another are concerns over the side effects of oral antibiotics and the potential risk of damage to the inner ear and hearing loss due to the use of antibiotic eardrops.
Study characteristics
This review includes evidence up to 23 June 2016. We included nine studies with a total of 2132 children who developed acute ear discharge beyond the immediate postoperative period. The studies evaluated a range of treatments.
Key results
We primarily looked at the difference in the proportion of children whose ear discharge had resolved within two weeks after treatment was started, adverse events and serious complications. Secondary outcomes were the proportion of children whose discharge had resolved at two to four weeks and four to 12 weeks, the proportion of children whose ear pain and fever had resolved within two weeks, the duration of discharge, the proportion of children with chronic discharge, discharge recurrences, tube blockage, tube extrusion, health-related quality of life and hearing.
Antibiotic eardrops (with or without corticosteroid) versus oral antibiotics
Antibiotic eardrops with or without corticosteroid were more effective than oral antibiotics in terms of resolution of ear discharge at one week (moderate-quality evidence) and two weeks (moderate-quality evidence), ear discharge recurrences (low-quality evidence) and disease-specific quality of life (low-quality evidence). We found no evidence that antibiotic eardrops were more effective in reducing the risk of chronic ear discharge (low-quality evidence), tube blockage (low-quality evidence), general quality of life (low-quality evidence) or hearing (very low-quality evidence). Adverse events occurred at similar rates (low-quality evidence), while no serious complications occurred in either of the groups (very low-quality evidence).
Other comparisons
Antibiotic eardrops with or without corticosteroid were more effective than corticosteroid eardrops in terms of duration of ear discharge (moderate-quality evidence).
Antibiotic eardrops were more effective than saline rinsing in terms of resolution of ear discharge at one week (moderate-quality evidence), but not in terms of tube blockage (low-quality evidence). Also, we cannot exclude an unimportant difference between antibiotic eardrops and saline rinsing in terms of resolution of discharge at one week.
Eardrops containing two antibiotics and a corticosteroid were more effective than no treatment in terms of resolution of ear discharge at two weeks (moderate-quality evidence), duration of ear discharge (moderate-quality evidence), reducing the risk of chronic ear discharge (low-quality evidence) and disease-specific quality of life (low-quality evidence). We found no evidence that antibiotic eardrops were more effective in terms of ear discharge recurrences (low-quality evidence) or general quality of life (low-quality evidence).
Low-quality evidence suggests that antibiotic and corticosteroid combination eardrops are more effective than eardrops containing antibiotics only in terms of resolution of ear discharge within two weeks and duration of ear discharge, but not in terms of resolution of ear discharge at two to four weeks or tube blockage. There is a substantial risk of publication bias, therefore these findings should be interpreted with caution.
Quality of evidence and conclusion
We found moderate to low-quality evidence that antibiotic eardrops (with or without corticosteroid) are more effective than oral antibiotics, corticosteroid eardrops and no treatment in children with ear discharge occurring at least two weeks following grommet placement. There is some limited, inconclusive evidence that antibiotic eardrops are more effective than saline rinsing. There is uncertainty whether antibiotic-corticosteroid eardrops are more effective than eardrops containing antibiotics only.
We found moderate to low-quality evidence that antibiotic eardrops (with or without corticosteroid) are more effective than oral antibiotics, corticosteroid eardrops and no treatment in children with ear discharge occurring at least two weeks following grommet insertion. There is some limited, inconclusive evidence that antibiotic eardrops are more effective than saline rinsing. There is uncertainty whether antibiotic-corticosteroid eardrops are more effective than eardrops containing antibiotics only.
Ear discharge (otorrhoea) is common in children with grommets (ventilation/tympanostomy tubes); the proportion of children developing discharge ranges from 25% to 75%. The most common treatment strategies include oral broad-spectrum antibiotics, antibiotic eardrops or those containing a combination of antibiotic(s) and a corticosteroid, and initial observation. Important drivers for one strategy over the other are concerns over the side effects of oral antibiotics and the potential ototoxicity of antibiotic eardrops.
To assess the benefits and harms of current treatment strategies for children with ear discharge occurring at least two weeks following grommet (ventilation tube) insertion.
The Cochrane ENT Information Specialist searched the ENT Trials Register, CENTRAL (2016, Issue 5), multiple databases and additional sources for published and unpublished trials (search date 23 June 2016).
Randomised controlled trials comparing at least two of the following: oral antibiotics, oral corticosteroids, antibiotic eardrops (with or without corticosteroid), corticosteroid eardrops, microsuction cleaning of the ear canal, saline rinsing of the ear canal, placebo or no treatment. The main comparison of interest was antibiotic eardrops (with or without corticosteroid) versus oral antibiotics.
We used the standard methodological procedures expected by Cochrane. Primary outcomes were: proportion of children with resolution of ear discharge at short-term follow-up (less than two weeks), adverse events and serious complications. Secondary outcomes were: proportion of children with resolution of ear discharge at intermediate- (two to four weeks) and long-term (four to 12 weeks) follow-up, proportion of children with resolution of ear pain and fever at short-term follow-up, duration of ear discharge, proportion of children with chronic ear discharge, ear discharge recurrences, tube blockage, tube extrusion, health-related quality of life and hearing. We used GRADE to assess the quality of the evidence for each outcome; this is indicated in italics.
We included nine studies, evaluating a range of treatments, with 2132 children who developed acute ear discharge beyond the immediate postoperative period. We judged the risk of bias to be low to moderate in most studies.
Antibiotic eardrops (with or without corticosteroid) versus oral antibiotics
Antibiotic eardrops with or without corticosteroid were more effective than oral antibiotics in terms of:
- resolution of discharge at one week (one study, 42 children, ciprofloxacin eardrops versus amoxicillin: 77% versus 30%; risk ratio (RR) 2.58, 95% confidence interval (CI) 1.27 to 5.22; moderate-quality evidence);
- resolution of discharge at two weeks (one study, 153 children, bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: 95% versus 56%; RR 1.70, 95% CI 1.38 to 2.08; moderate-quality evidence);
- duration of discharge (two studies, 233 children, ciprofloxacin eardrops versus amoxicillin: median 4 days versus 7 days and bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: 4 days versus 5 days; moderate-quality evidence);
- ear discharge recurrences (one study, 148 children, bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: 0 versus 1 episode at six months; low-quality evidence); and
- disease-specific quality of life (one study, 153 children, bacitracin-colistin-hydrocortisone eardrops versus amoxicillin-clavulanate: difference in change in median Otitis Media-6 total score (range 6 to 42) at two weeks: -2; low-quality evidence).
We found no evidence that antibiotic eardrops were more effective in terms of the proportion of children developing chronic ear discharge or tube blockage, generic quality of life or hearing.
Adverse events occurred at similar rates in children treated with antibiotic eardrops and those treated with oral antibiotics, while no serious complications occurred in either of the groups.
Other comparisons
(a) Antibiotic eardrops with or without corticosteroid were more effective than corticosteroid eardrops in terms of:
- duration of ear discharge (one study, 331 children, ciprofloxacin versus ciprofloxacin-fluocinolone acetonide versus fluocinolone acetonide eardrops: median 5 days versus 7 days versus 22 days; moderate-quality evidence).
(b) Antibiotic eardrops were more effective than saline rinsing of the ear canal in terms of:
- resolution of ear discharge at one week (one study, 48 children, ciprofloxacin eardrops versus saline rinsing: 77% versus 46%; RR 1.67, 95% CI 1.04 to 2.69; moderate-quality evidence);
but not in terms of tube blockage. Since the lower limit of the 95% CI for the effect size for resolution of ear discharge at one week approaches unity, a trivial or clinically irrelevant difference cannot be excluded.
(c) Eardrops containing two antibiotics and a corticosteroid (bacitracin-colistin-hydrocortisone) were more effective than no treatment in terms of:
- resolution of discharge at two weeks (one study; 151 children: 95% versus 45%; RR 2.09, 95% CI 1.62 to 2.69; moderate-quality evidence);
- duration of discharge (one study; 147 children, median 4 days versus 12 days; moderate-quality evidence);
- chronic discharge (one study; 147 children; RR 0.08, 95% CI 0.01 to 0.62; low-quality evidence); and
- disease-specific quality of life (one study, 153 children, difference in change in median Otitis Media-6 total score (range 6 to 42) between groups at two weeks: -1.5; low-quality evidence).
We found no evidence that antibiotic eardrops were more effective in terms of ear discharge recurrences or generic quality of life.
(d) Eardrops containing a combination of an antibiotic and a corticosteroid were more effective than eardrops containing antibiotics (low-quality evidence) in terms of:
- resolution of ear discharge at short-term follow-up (two studies, 590 children: 35% versus 20%; RR 1.76, 95% CI 1.33 to 2.31); and
- duration of discharge (three studies, 813 children);
but not in terms of resolution of discharge at intermediate-term follow-up or proportion of children with tube blockage. However, there is a substantial risk of publication bias, therefore these findings should be interpreted with caution.