A review of treatments for aural hematomas in dogs Review question: When treating aural hematomas in dogs, what is the evidence that the inclusion of the
use of steroids, alone or in combination with other treatments reduces the number of dogs that must be
retreated?
Bottom line. There are many ways that aural hematomas are treated in dogs. The articles reviewed
examined hematoma drainage in combination with either oral or local injections of steroids, and traditional
surgical treatment. There was no evidence that adding steroids to treatment protocols reduced the
number of dogs that needed to be retreated. The quality of the evidence was poor which limits any
interpretation that may be made.
Key elements of the review question?
• Population of interest: Dogs with aural hematoma
• Intervention of interest: Therapies that include the use of steroids, alone or in combination with other
therapeutic options
• Comparison of interest: Therapies that do not include the use of steroids, alone or in combination
with other therapeutic options
• Outcome of interest: A reduction in the number of dogs that must be retreated.
Plain language summary: It was not possible to answer the question if the use of steroids, alone or in
combination with other therapeutic options, was associated with improved resolution of aural hematomas
in dogs as only two poorly described and, possibly poorly executed studies, included a comparison group.
One comparative study did not report the numerical results, enrolled only 4 dogs per group, did not report
inclusion criteria for the dogs, did not report randomization to group and blinding of outcome assessment.
The other study did not conduct a statistical analysis comparing groups (the study was likely
underpowered), did not report inclusion criteria for the dogs, reported using inadequate randomization
methods to allocate animal to group ( i.e., no blocking or stratification resulting in uneven group sizes (4 to
13) and no blinding of outcome assessment. The majority of available studies were case series with
unspecified rationale for inclusion of dogs. None of the case series reported using methods to mask the
person assessing the outcome to the treatment received. The absence of blinding increases the potential
that the estimates of response to therapy in the case series are higher than might be expected in a
controlled trial.
Evidence profile: The level of evidence for support the use of steroids to be very low quality which
means we remain very uncertain about the true prevalence of recovery from aural hematoma and
impact of the addition of steroids. It is likely the effect is substantially different from those
reported due to potential for bias. This determination was based on the following characteristics
1
recommended by the GRADE working group
1) Design – Initial quality of evidence is considered very low because the majority of designs were
case series or lower-powered comparative trials,
2) Risk of bias- The risk of bias is considered very serious as most studies did not report enrollment
criteria, lacked a control group or used no or inadequate randomization and no blinding.
3) Inconsistency – The impact of inconsistency could not be assessed, as there were only 2
comparison studies,
4) Indirectness bias – This was considered very serious, as subjective outcomes such as fair, good
poor were used by many studies
5) Imprecision bias - The impact of random error was considered very serious because the
comparative studies were very small.
6) Publication bias - The risk of publication bias is very serious because the studies were small and
case series strongly favor positive outcomes
Prepared by Dr. Teresa Hershey and Dr. Annette O'Connor with the assistance of Nicole
Hershberger for the EBVMA practitioner committee. 18 September 2011
A review of treatments for aural hematomas in dogs Table 1: Details of studies identified by the search that reported treatment for aural hematoma in dogs.
Study
Design
Case
Series
3
Case
Series
4
Case
Series
5
Comparati
ve Study
(4 groups)
2
5
5
5
Intervention
Evacuate hematoma, no drain,
injectable steroid locally, 7-days
oral steroids, no antibiotics, no or
light bandage
Evacuate hematoma, silicon
rubber drain, injectable steroid
locally given day 1, no oral
steroids, no antibiotics, no
bandage
Evacuate hematoma, closedsuction drain, no injectable
steroid locally, no oral steroids,
no antibiotics, immobilizing
bandage
Evacuate hematoma, PCV drain,
no injectable steroid locally,
injectable steroids given day 1,
antibiotics given day 1-5,
pressure bandage
Evacuate hematoma, latex drain,
no injectable steroid locally,
injectable steroids given day 1,
antibiotics given day 1-5,
pressure bandage
Conventional surgical method, no
injectable steroid locally,
injectable steroids given day 1,
antibiotics given day 1-5,
pressure bandage
Evacuate hematoma, silicon
drain, no injectable steroid
locally, injectable steroids given
day 1, antibiotics given day 1-5,
pressure bandage
Outcome
Healing grade not described.
Failure to return for surgery
interpreted as successful
outcome.
Healing grade not described.
Assessor was not described.
Recurrence reported.
Follow-up
Not
described
# Dogs
30
# Resolved (%)
29 (97%)
Randomized
Not
applicable
Blinded
No
Between 2
and 9
months
9
7 (78%)
Not
applicable
No
Healing graded using an undescribed scale. Assessor
was the owner.
Between 3
and 23
months
9
7 (78%)
Not
applicable
No
Healing graded as excellent,
good, poor. Assessor was
not described.
Not
described
4
Healing reported
as poor to good
No
No
(as above)
Not
described
4
Healing reported
as good
No
No
(as above)
Not
described
4
Healing reported
as poor to good
No
No
(as above)
Not
described
4
Healing reported
as excellent
No
No
Prepared by Dr. Teresa Hershey and Dr. Annette O'Connor with the assistance of Nicole Hershberger for the EBVMA practitioner
committee. 18 September 2011
A review of treatments for aural hematomas in dogs Study
Design
Case
Series
7
Comparati
ve Study
(5 groups)
6
7
7
7
7
Intervention
Evacuate hematoma, bovine teat
tube, no injectable steroid locally,
no injectable steroids given, no
antibiotics given, bandage
Conventional surgical method, no
injectable steroid locally no
injectable steroids given,
chloramphenicol (25mg/kg BW)
PO every 8 hours for 10 days,
pressure bandage
Evacuate hematoma, no drain,
no injectable steroid locally, 2
mg/kg BW dexamethasone
injectable steroids daily until
resolution, gentamicin (4mg/kg
BW) daily to resolution, no
bandage
Evacuate hematoma, no drain,
no injectable steroid locally,
0.5mg/kg BW dexamethasone
injectable steroids daily until
resolution, gentamicin (4mg/kg
BW) daily to resolution, no
bandage
Evacuate hematoma, no drain,
0.2 to 0.4 mg dexamethazone
and 0.25 mg of gentamicin in
physiological saline injected daily
in cavity,0.5mg/kg BW
dexamethasone injectable daily
until resolution, gentamicin
(4mg/kg BW) daily to resolution,
no bandage
Evacuate hematoma,
physiological saline flush daily in
cavity, no injectable steroids, no
Outcome
Healing grade not described.
Resolution described as no
complications.
Follow-up
Not
described
# Dogs
35
# Resolved (%)
30 (86%)
Randomized
Not
applicable
Blinded
No
Healing graded from A
(healed, no morphological
changes) to D (severe
morphological changes).
Grades A and B regarded as
satisfactory healing.
Assessor was not described.
(as above)
2 months
10
6 (60%)
Yes
No
2 months
13
11 (85%)
Yes
No
as above
2 months
8
3 (38%)
Yes
No
as above
2 months
9
8 (89%)
Yes
No
as above
2 months
4
0 (0%)
Yes
No
Prepared by Dr. Teresa Hershey and Dr. Annette O'Connor with the assistance of Nicole Hershberger for the EBVMA practitioner
committee. 18 September 2011
A review of treatments for aural hematomas in dogs Study
Design
8
Case
Series
9
Case
Series
10
Case
Series
Intervention
antibiotics, no bandage
Evacuate hematoma, Penrose
drain, no local steroids, 1mg/kg
BW prednisolone PO twice daily
for 14 days, followed by 1 mg/kg
BW once daily for 14 days, no
antibiotics, no bandage described
Evacuate hematoma, CO2 laser
surgical approach, an unspecified
course of topical steroids, 2 dogs
received an unspecified course of
systemic prednisilone,
Cephaxalin (20 mg/kg BW or
amoxacillin/clavulanic acid (15
mg/kg BW) PO q 12 hours for
10-14 days followed by 1 mg/kg
BW once daily for 14 days,, no or
immobilizing bandage
Evacuate hematoma, no drain,
0.25 mg/kg BW of
dexamethazone and 1 mg/kg BW
of gentamicin injected daily in
cavity every 24-48 as needed, no
injectable steroids, no antibiotics,
no bandage
Outcome
Follow-up
# Dogs
# Resolved (%)
Randomized
Blinded
Successful if outcome has
no recurrence i.e., repeat
treatment. Assessor was not
described.
Not
described
22
19 (87%)
Not
applicable
No
Healing graded as good, fair,
poor. Good considered a
success. Assessor was not
described.
12 months
8
6 (75%)
Not
applicable
No
Successful if outcome has
no recurrence (i.e., repeat
treatment). Assessor was
not described.
Not
described
10
8 (80%)
Not
applicable
No
Prepared by Dr. Teresa Hershey and Dr. Annette O'Connor with the assistance of Nicole Hershberger for the EBVMA practitioner
committee. 18 September 2011
A review of treatments for aural hematomas in dogs Search Strategy: PubMed was searched on January 31, 2011 using key word phrases: “aural
hematoma dog” retrieved 10 citations, “canine aural hematoma” retrieved 12 citations, “auricular
haematoma dog” retrieved 5 citations. Some articles appeared under all or at least two of the searches
with 18 unique citations identified in PubMED. We searched CAB abstracts using the terms “aural
hematoma canine” which retrieved 13 citations. In CAB the search “auricular haematoma canine” yielded
two already identified citations. Of the thirteen articles obtained from the CAB Abstracts five were also
found in the PubMed search and seven were unique. The total of 25 unique articles found in Cab and
PubMed were then screened for relevance using the criteria that the article must discuss a treatment for
aural hematomas. Six articles were deemed relevant and full text obtained, several required interlibrary
loans to obtain 2-6,9. The reference sections of the six relevant articles were searched for additional
citations and three additional relevant studies identified 7,8,10. We also conducted searches in PubMed
looking for biomedical studies using rabbits as models for “cauliflower ear” or “aural hematoma” but none
of the citations retrieved were relevant to the review. The Cochrane Review database was search for
aural hematoma retrieved 11 citations, none of which were relevant. Finally, we also searched the titles of
presentations at the annual meeting of the American Veterinary Medical Association and The College of
Internal Veterinary Medicine from 2000 to 2011 and found no relevant citations. In summary, the search
identified 9 relevant citations and the data extracted are reported in Table 1 .
References:
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summary of findings tables. Journal of Clinical Epidemiology 2011;64:383-94.
2. Romatowski J. Nonsurgical treatment of aural hematomas. Journal of American Veterinary Medical
Association 1994;204:1318.
3. Kagan KG. Treatment of canine aural hematoma with an indwelling drain. Journal of American
Veterinary Medical Association 1983;183:972-4.
4. Swaim SF, Bradley DM. Evaluation of closed-suction drainage for treating auricular hematomas.
Journal of the American Animal Hospital Association 1996;32:36-43.
5. Ahirwar V, Chandrapuria VP, Bhargava MK, et al. A comparative study on the surgical management of
canine aural haematoma. Indian Journal of Veterinary Surgery 2007;28:98-100.
6. Wilson JW. Treatment of auricular hematoma, using a teat tube. Journal of American Veterinary
Medical Association 1983;182:1081-3.
7. Kuwahara J. Canine and feline aural hematomas: Results of treatment with corticosteroids. Journal of
the American Animal Hospital Association 1986;22:641-7.
8. Joyce JA. Treatment of canine aural haematoma using an indwelling drain and corticosteroids. Journal
of Small Animal Practice 1994;35:341-4.
9. Dye TL, Teague HD, Ostwald DA, Jr., et al. Evaluation of a technique using the carbon dioxide laser
for the treatment of aural hematomas. Journal of American Animal Hospital Association 2002;38:385-90.
10. Aithal HP, Kinjavdekar P, Amarpal, et al. Treatment of aural haematoma with local administration of
dexamethasone in dogs. Indian Veterinary Journal 2000;77:619-22.
Prepared by Dr. Teresa Hershey and Dr. Annette O'Connor with the assistance of Nicole
Hershberger for the EBVMA practitioner committee. 18 September 2011