Comparison of Care Settings for Pediatric External Auditory Canal Foreign Bodies: A Meta-Analysis

Abstract

Objective:

To compare the success and complication rates of pediatric external auditory canal foreign body (EAC FB) removal between Emergency Departments (ED), Primary Care Providers (PCP), and Otolaryngologists (ENT).

Methods:

PubMed, Scopus, and Embase were searched through January 13, 2022. Studies mentioning EAC FB removal success rates and types of healthcare settings were included. Pooled measures included abrasions/lacerations, TM perforations, and success rate stratified by healthcare setting.

Results:

Thirteen studies and 3891 patients were included in the meta-analysis. Most comparisons between EAC FB removal success rates for EDs versus PCPs versus ENTs were statistically significant. The highest FB removal success rate was in patients who presented to ENTs without previous removal attempts (92.9% [95% CI 84.6-98.2]). EDs had the lowest success rates (64.0% [95% CI 48.3-78.3]). For patients that had a previous attempt at FB removal, ENTs had a success rate of 64.1% [95% CI 42.0-83.5].

Conclusions:

For ENTs treating pediatric EAC FB, removal success rates decrease if a different healthcare provider previously attempted EAC FB removal. This effect likely is due to decreased patient cooperativeness or increased FB complications (eg, canal edema and bleeding limiting visualization) after previous removal attempts. Individual institutions should identify conditions that increase EAC FB removal failure rates and necessitate ENT referral. Therefore, the communication and concerted efforts between EDs, PCPs, and ENTs are critical for the improved outcomes of pediatric EAC FBs.

Keywords

external auditory canal foreign body evidence-based medicine pediatric otolaryngology

Introduction

Foreign bodies (FB) of the external auditory canal (EAC) are a frequent problem in the pediatric population, with most affected children younger than 8 years old.^1-4 Common FBs include beads, stones, organic matters, paper, etc.^5-8 Because many common FBs are perceived as non-threatening, parents often attempt to remove the FB from the child’s ear prior to seeking medical help.

However, removing EAC FBs can present risks to the patient and requires skilled personnel, especially in the pediatric population. If removal is not performed correctly, complications may include trauma to the EAC, otitis externa, otalgia, or conductive hearing loss due to tympanic membrane (TM) perforations and/or ossicular chain disruption.^9-11 The rate of complications increases when the patient cannot remain calm and still during treatment. For example, Marin and Trainor described a child who suffered a TM perforation and ossicle disruption due to repeated removal attempts in an emergency department (ED) without restraints. General anesthesia (GA) was required to perform the FB removal and ossicular chain reconstruction.¹¹

Patients with EAC FBs may present to different types of healthcare settings. These care settings include EDs, primary care provider (PCP) offices, and otolaryngology (ENT) clinics. Most referrals to ENT clinics are made after another healthcare provider has a failed FB removal attempt.^8,11 However, manipulation of the FB increases the risk for complications; even just 1 or 2 failed attempts can quickly increase a child’s stress levels, thereby decreasing patient cooperation during treatment and further increasing risk for complications.¹² To avoid complications when patient cooperation is lost, children may require GA, which carries its own risks.¹³ It is therefore imperative to consider what healthcare setting and method of removal would be the most efficacious and efficient. This systematic review and meta-analysis aimed to examine differences in EAC FB removal success and complication rates between EDs, PCPs, and ENT clinics.

Methods

Data Collection and Selection

This study was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.¹⁴ To identify studies for inclusion, search strategies were developed in the following 3 databases: PubMed (National Library of Medicine, National Institutes of Health), Scopus (Elsevier), and Embase (Elsevier). The search strategies used a combination of title terms and keywords for the following 2 concepts: external auditory canal and foreign bodies. The PubMed search strategy was modified by maintaining similar keywords for the other 2 databases. The search strategies for each database are detailed in Supplemental Appendix 1. The databases were searched from inception through January 13, 2022, and results were limited to the English language only. To identify additional articles, the reference lists of included articles were hand-searched. References were uploaded to Covidence systematic review software (Veritas Health Innovation, Melbourne, Australia) and screened for relevance.

Selection Criteria

Only studies with the primary objective of examining FB removal from the EAC in pediatric patients were included. Abstracts were first independently reviewed by 2 reviewers (A.C.W. and M.S.) to identify all articles pertaining to the treatment of FBs in the EACs of children. Non-English studies, nonhuman studies, and non-journal articles (eg, abstract only, poster presentations) were excluded. Review articles were first included to screen their content and references but were excluded from the final analyses.

Studies were considered for inclusion in the final analysis if they (1) involved only pediatric patients, involved patients presenting to a children’s hospital, or had sub-analyses specific to ages 0 to 18 years; (2) mentioned the type of care facility from which the data was collected; and (3) mentioned a removal success rate for each care facility.

Outcome measures were extracted by 2 reviewers (A.C.W. and M.S.) and included in the analysis and discussion. Disagreements were resolved in a discussion between the same 2 reviewers. Primary outcome measures included removal success rates of each facility and complication rates of each facility and patient category. Success rates were grouped according to ED, PCP, ENT initial attempts, and ENT after a previous attempt by another provider. Patients that required general anesthesia were considered unsuccessful attempts by the associated providers. For EDs and PCPs, there was insufficient information to stratify by first versus subsequent attempt at FB removal.

The level of evidence for each selected article was evaluated with the Oxford Center for Evidence-Based Medicine.¹⁵ The risk of bias was assessed according to the Cochrane Handbook for Systematic Reviews of Interventions version 6.2, 2021. Two authors (A.C.W. and M.S.) performed a pilot assessment on 3 studies to check for consistency of assessment. They then performed an independent risk assessment on the remaining studies. All disagreements were resolved by way of discussion between the 2 authors. The risk of bias for each aspect is graded as “low,” “unclear,” or “high.”

Statistical Analysis

Meta-analysis of proportions was performed using MedCalc 20.008 (MedCalc Software, Belgium). Pooled measures included abrasions/lacerations, TM perforations, sedation, and success rate. Each measure was weighted according to the number of patients affected. MedCalc used a Freeman-Tukey transformation to calculate the weighted summary proportion under the fixed and random-effects models.^16,17 Data were presented as weighted proportions with corresponding 95% confidence intervals (CI). Both the fixed effects model and the random-effects model were used in this study.¹⁸ If there was high heterogeneity (I² > 50%), then a random-effects model was used; if low heterogeneity, a fixed-effects model was used. A P value of <.05 was considered to indicate a statistically significant difference for all statistical tests. Finally, potential publication bias was evaluated by visual inspection of the funnel plot and Egger’s regression test.¹⁹

All studies were analyzed together, and a sub-analysis of the United States of America (USA)-only studies was also conducted because healthcare infrastructure differs significantly between countries. Most included studies were conducted in the USA, and therefore the greatest generalizability and relevant analyses would be for the USA.

Results

Included Studies

In total, 13 studies were included in the meta-analyses.^{1,3-8,11-13,20-22} A PRISMA diagram outlining the literature search is shown in Figure 1. Included studies were published between 1987 and 2021 and originated from 6 countries. Critical appraisal of studies indicated an acceptably low risk of bias for most included studies (Figure 2), with only 1 study showing a high risk of bias with bias in selecting participants. A funnel plot (Figure 3) demonstrated 9 out of 13 studies lying within the funnel, and Egger’s test (−2.2517, P = .7327) was not significant, indicating little to no publication bias. Data was reported on 3891 patients between 2 months and 20 years of age. The included studies are summarized in Table 1. The reported gender was 1473 males and 1220 females (5 studies did not report gender counts).

Table 1.

Summary of Included Studies.

Studies	Country	OCEBM Level of Evidence	Age Mean (SD)	Age Median (IQR)	Age Range (years)	N Total	N Male (%)	N ED	% Success ED	N PCP	% Success PCP	N ENT initial attempt	% Success ENT initial attempt	N ENT after a failed attempt	% Success ENT after a failed attempt	N (%) Requiring Sedation
Baker¹	USA	4	6.6	6 (4-9)	2-16	134	66 (49.3)	134	88.1							1 (0.7)
Balbani et al.²	Brazil	3			0-12	93										43 (8.6)
Brown et al.²⁰	USA	4		4.6 (4.3-9.3)	1.4-17.6	174	109 (62.6)	159	84.3							43 (25.0)
Cederberg et al.¹³	USA	3	6	5.5	0.7-17.6	85										17 (19.5)
DiMuzio⁶	USA	4	6.2		1-16	34		34	52.9
Endican et al.⁷	Papua New Guinea	4			0-16	711										98 (13.6)
Fasunla et al.³	Nigeria	4	4.8	4	2-15	323	171 (52.9)
Karimnejad et al.²¹	USA	4	6.6			1197	659 (55.1)	759	67.9			438	92.9	186	78.5	71 (5.9)
Lou⁴	China	4			0-16	191	75 (39.3)									53 (27.7)
Mackle and Conlon⁸	Ireland	4	4.5		1-14	58	33 (56.9)	33	12.1			25	76.0	29	13.8	25 (53.4)
Marin and Trainor¹¹	USA	4	6.6		0.2-20	250	157 (62.8)	244	83.6			10	90.0	40	65.0	15 (6.0)
Mingo et al.²²	USA	4			1-18	275		133	88.0	60	75.0	44	95.5	38	65.8	18 (6.5)
Shih et al.¹²	USA	4	6.5		1-16	366	203 (55.5)	63	17.5	223	76.2	87	100.0	96	89.6	10 (2.7)

Analyses Involving All Studies

Differences in removal success rates between healthcare provider types were statistically significant in every comparison except ED versus ENTs after a previous failed attempt (P = 0.95). ENTs who provided the first attempt at FB removal had the highest success rate (92.9%) (Table 2, Figure 4). EDs had the lowest success rate (64.0%). Differences in the number of abrasions and/or lacerations (A/L) and TM perforations observed by the provider were significant in all comparisons. A/Ls and TM perforations were most commonly observed by ENTs who removed a FB after a previous failed attempt (35.6% and 10.3%, respectively). For ENTs, patients that had a previous failed attempt were more likely to require GA or sedation (46.0%) than those who presented first to an ENT (7.1%) (P < 0.0001).

Table 2.

Meta-Analyses Data From All Studies.

		ED	PCP	ENT initial attempt	ENT after failed attempt
Success rates	n (%)	1559 (64.0)*	283 (75.8)	604 (92.9)	389 (64.1)*
Success rates	95% CI	(48.3-78.3)	(70.4-80.7)	(84.6-98.2)	(42.0-83.5)
A/L	n (%)	855 (12.3)	-	593 (4.2)	402 (35.57)
A/L	95% CI	(3.1-26.3)	-	(1.2-9.0)	(1.3-48.2)
TM Perf.	n (%)	1621 (0.3)^†	-	1520 (0.2)^†	691 (10.3)
TM Perf.	95% CI	(0.1-0.7)	-	(0.1-0.6)	(1.3-48.3)
Patients Needing GA or Sedation	n (%)	-	-	604 (7.1)	467 (46.0)
Patients Needing GA or Sedation	95% CI	-	-	(1.8-15.4)	(21.4-71.7)

ENT initail attempt = patients who initially presented to the ENT clinic; successful FB removal in clinic.

ENT after failed attempt = patients who presented to ENT clinic after at least 1 previous removal attempt; successful FB removal in clinic.

A/L = EAC abrasions and/or lacerations.

TM Perf. = tympanic membrane perforation.

Not a significant comparison between the 2 marked groups.

†

Not a significant comparison between the 2 marked groups.

Sub-Analyses for Studies in the United States Only

Eight studies were published in the United States (US).^{1,6,11-13,20-22} Seven of these eight studies were conducted in care settings specific to pediatric populations (eg, children’s hospitals or pediatric emergency departments), and all 8 studies were in tertiary care centers. Included studies were published between 1987 and 2021. A funnel plot (Figure 5) demonstrated 7 out of 8 studies lying within the funnel, and Egger’s test (−3.3135, P = .4172) was not significant, indicating little to no publication bias. Data was reported on 2515 patients between 2 months and 20 years of age. The reported gender was 1194 males and 927 females (3 studies did not report gender counts). Table 3 shows data only from the included studies originating in the US. Differences in removal success rates were significant in every comparison except for ED versus PCP (P = .096) and ENTs versus PCP after a previous failed attempt (P = .89). The success rates in the US resembled global trends; ENTs who provided the first attempt at FB removal had the highest success rate (95.6%), and EDs had the lowest (70.9%). While studies performed in the US provided information regarding A/Ls and TM perforations in EDs, PCPs, and ENTs, only the data for EDs was sufficient in volume for meta-analysis. Consistent with overall data, patients that presented to ENTs after a previous failed attempt were more likely to require GA or sedation (24.3%) than those that presented first to ENTs (4.5%) (P < .0001).

Table 3.

Meta-analyses data for the US studies only.

	ED	PCP	ENT initial attempt	ENT after failed attempt
Success rates
n (%)	1526 (70.9)*	283 (75.8)*^†	579 (95.6)	360 (76.2)^†
95% CI	(56.7-83.4)	(70.4-80.7)	(88.7-99.3)	(64.5-86.2)
A/L
n (%)	822 (12.0)	—	—	—
95% CI	(1.1-26.0)	—	—	—
TM Perf.
n (%)	822 (0.4)	—	—	—
95% CI	(0.1-1.1)	—	—	—
Patients Needing GA or Sedation
n (%)	—	—	579 (4.5)	360 (24.3)
95% CI	—	—	(0.7 – 11.3)	(13.8 – 36.7)

ENT initial attempt = patients who initially presented to the ENT clinic; successful FB removal in clinic.

ENT after failed attempt = patients who presented to ENT clinic after at least 1 previous removal attempt; successful FB removal in clinic.

A/L = EAC abrasions and/or lacerations.

TM Perf = tympanic membrane perforation.

Not a significant comparison between the 2 marked groups.

†Not a significant comparison between the 2 marked groups.

Discussion

The purpose of this meta-analysis was to assess and compare the success and complication rates of EAC FB removal in EDs, PCP offices, and ENT clinics. Regardless of geography, first attempts by ENTs had the highest success rate, while EDs had the lowest. Complication rates, and therefore the likelihood of patients requiring GA, tended to be highest when there were previous failed attempts at FB removal. Understanding potential explanations for differences in success rates between healthcare providers is imperative to reducing disparities in FB removals between care settings and improving associated outcomes for children.

FB removal success is dependent on 4 major factors:

(1) The nature of the FB

(2) The patient’s ability to cooperate with FB removal

(3) The skill and training level of the provider attempting removal

(4) The tools available for the provider.

Certain conditions and characteristics of EAC FBs pose a heightened risk even before attempted removal. If the FB is spherical, not easily grasped, or abutting the TM, the child should be referred directly to an ENT clinic if possible to avoid further damage to the ear.¹⁰ Irregular-shaped FBs tend to be easier to remove but may cause irritation and swelling of the EAC that complicate removal. However, the current study does not show that the nature of the FB significantly alters the removal success rates between studies and provider types.

Key patient characteristics for successful FB removal are the child’s cooperativeness and patience. If a child is unable to cooperate during treatment, removal attempts are more likely to fail, complications are more likely to occur, and the patient is more likely to require GA for successful FB removal. These ideas are exemplified by comparing ENTs providing first versus secondary attempts at FB removal. Despite having access to the same tools, secondary attempts by ENTs had significantly lower success rates than primary attempts by ENTs in analyses of all studies and the sub-analyses of US studies. The lower success rate is likely due to children’s patience being exhausted by previous removal attempts, pain caused by existing complications, general loss of trust in healthcare personnel due to their failed attempts, or previous attempts further complicating the EAC FB removal (eg, pushing the FB deeper into the EAC). As highlighted by our finding that 1 in 4 US children (and nearly half of children across the world) treated by an ENT after a previously failed removal attempt required GA, it is recommended that if there is concern regarding the safety or possible success of the FB removal, the provider should err on the side of caution and refer to ENT if possible before attempting removal.

A potential confounder is that the FBs presented to ENTs after a previous failed attempt may be inherently harder to remove in nature, which may account for EDs or PCPs first failing at removal. However, when the PCP or ED determines a FB episode too difficult for removal with their accessible tools, the patient should be referred to ENT if an ENT is easily accessible. Therefore, both scenarios involve cases complicated or challenging FB removals. The dramatic difference in the success rates between primary versus secondary attempts by ENTs is likely due to a different variable (ie, patient cooperativeness).

While otoscopes are commonplace in EDs and PCPs, ENT clinics have unique access to otomicroscopy. Access to otomicroscopy alone gives ENTs an advantage when removing EAC FBs, accounting for the very high success rates for patients that present first to an ENT. Furthermore, ENT clinics are equipped with various sizes and styles of suction devices, curettes, and other specialized tools that are more suitable for pediatric patients. Finally, ENTs have trained nurses and various forms of restraints such as papoose boards. While this study does not capture the role of nurses in FB removal, at the author’s institution (Texas Children’s Hospital), ENT nurses are specifically trained to hold children in positions that maximize the ease and safety of FB removal. Such tools and techniques are not available or commonly practiced in most EDs and PCP offices, contributing to the lower removal success rates in these settings. Lower success rates in these settings may also be due to some standard methods of FB removal in EDs, such as the use of adhesive-tipped probes (eg, superglue on a cotton swab) and L-shaped hooks, which are not suitable for uncooperative children and have a high risk of causing removal failure and significant injury.^12,23

Equipping EDs and PCPs with specialized tools such as otomicroscopy may be beneficial but not without specialized training. Schulze found that when ENTs used direct visualization to remove FBs, the removal success rate was 64%. The success rate then increased to 83% with the use of otomicroscopy.²⁴ When otomicroscopy was used by ENT residents on patients referred from the ED, the success rate was 76%.¹³ These findings show that the otomicroscopy does improve the removal success rate, but a certain level of training is required to maximize the benefit of this tool. However, implementing proper otomicroscopy training into the standard education of ED and PCP personnel would require systemic changes.

Most EDs are not specific to pediatric patients. Non-pediatric ED personnel often lack the experience and training required to safely remove a FB from a child’s ear. Similarly, children’s PCPs are not always pediatricians and include family or internal medicine doctors with varying pediatric training and experience levels. Provider skill at pediatric FB removal is difficult to assess, and the current study does not accurately reflect or compare the abilities of pediatric-specific EDs, pediatricians, or other EDs and PCPs.

It is important to note that this study could not evaluate referral patterns. For example, a patient may see a PCP before being referred to ENT. By contrast, a patient may see a PCP, visit an ED, and finally see an ENT. These different pathways show how EDs and PCPs are critical healthcare team members for EAC FB patients achieving the best outcomes. By determining what EAC FB cases should be directly referred to ENTs, patients may be spared additional attempts at FB removal and associated risks for complications. Therefore, future directions include more studies that analyze characteristics of EAC FB and patients that highlight a need for immediate ENT referral.

Limitations

Marin and Trainor’s study only included patients at a pediatric hospital; however, this study included a few 20-year-old patients, which opposes the standard age group considered pediatric. Because there were fewer than five 20-year-olds included in the current systematic review and meta-analysis (n = 3891), the effect of the data collected from the 20-year-olds is negligible, and the results of this study are still generalizable to pediatric populations.¹¹

Only 2 studies for EAC FB removal success rates for PCPs were available, and therefore the results of the meta-analysis are weaker for PCPs. A greater number of studies examining the success rates of PCPs, with consideration of incidentally noticed EAC FBs versus EAC FBs as a primary complaint, are needed.

The current meta-analysis shows that previous failed attempts are associated with higher complication rates, but it cannot be concluded that these complications were caused by ED or PCP personnel. Additionally, the data presented for complication rates likely have high levels of reporting bias. Providers that attempt FB removal may be incentivized to refrain from reporting any resulting complications. Furthermore, skill level may affect whether complications are visualized or noticed after FB removal. Therefore, the true rates of complications cannot be accurately determined from the current data.

Our study could not analyze differences in initial versus secondary attempts for EDs and PCPs. Similarly, this study could not consider referral bias or details of care received prior to presentation. Furthermore, levels of training (eg, registrar or resident vs attending physician) and provider qualifications (eg, nurse practitioner vs physician) were not distinguished in most studies for removal attempts. The currently available literature does not allow for the examination of these variables through meta-analysis. Future directions should examine which variables should or could be altered to improve patient outcomes.

The included US studies were conducted in only tertiary care centers in major urban areas. Therefore, these findings are not extrapolatable to rural areas in the US. Because rural areas do not often have nearby ENT clinics, it is reasonable for the nearest possible provider to attempt FB removal rather than referring to an ENT clinic. Further studies may be done to determine if there is a significant difference in success rate between urban and rural settings.

Conclusions

Our work elucidates disparities in FB removals between healthcare settings. ENTs that provided first attempts at FB removal had the highest success rates, and EDs had the lowest. ENT removal success rates were consistently lower than after another provider attempted removal, likely due to decreased patient cooperativeness or increased FB complications after successive removal attempts. Because of differences in healthcare structures within and between countries, concrete umbrella recommendations cannot be made for when to attempt FB removal versus directly referring to an ENT. Instead, individual institutions should identify conditions that increase EAC FB removal failure rates and necessitate ENT referral. Therefore, the communication and concerted efforts between EDs, PCPs, and ENTs are critical for the improved outcomes of pediatric EAC FBs.

Supplemental Material

sj-docx-1-aor-10.1177_00034894221093584 – Supplemental material for Comparison of Care Settings for Pediatric External Auditory Canal Foreign Bodies: A Meta-Analysis

Supplemental material, sj-docx-1-aor-10.1177_00034894221093584 for Comparison of Care Settings for Pediatric External Auditory Canal Foreign Bodies: A Meta-Analysis by Ana C. White, Michael C. Shih, Shaun A. Nguyen and Yi-Chun Carol Liu in Annals of Otology, Rhinology & Laryngology

Footnotes

Authors’ Note

Presentations: none

Author Contributions

Ana C. White – design, conduct, analysis, manuscript writing. Michael C. Shih, BS – Design, conduct, analysis, manuscript writing. Shaun A. Nguyen, MD – conduct, analysis, manuscript writing. Yi-Chun Carol Liu, MD – design, conduct, analysis, manuscript writing.

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

ORCID iD

Michael C. Shih

Supplemental Material

Supplemental material for this article is available online.

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