Ear Hematomas: Symptoms, Causes, Treatment & Prevention

What is an Ear Hematoma?

An ear (or aural) hematoma is a collection of blood between the two pieces of cartilage that make up the structure of a dog’s or cat’s ear.

An ear hematoma is sometimes called a blood blister because it looks like -- you guessed it -- a blister full of blood. It isn't likely to be dangerous, but it can be painful. And the longer it’s left untreated, the more scar tissue may develop, which (in some cases) may cause the ear to become permanently disfigured. 

But where do they come from? Why do our pets get aural hematomas?

What Causes Ear Hematomas in Cats & Dogs?

It’s usually caused by excessive head shaking or scratching due to an infection or some other form of irritation, like allergies or parasites.

According to one study, 50% of cats developed an aural hematoma after scratching excessively due to ear mites. In 43% of dogs, it was caused by an ear infection or inflammation causing them to scratch excessively.

There are several types of infection that can cause ear itch:

• Mites (parasites)
• Allergies
• Ear infections/inflammation
• Yeast
• An object judged inside the ear canal
• Cushing’s syndrome

Dogs with floppy ears are at a much higher risk of developing an ear hematoma than pets with perky ears. The blood vessels in the floppy part of the ears are more prone to rupture from the force of head shaking. They're also at a higher risk of being nipped when playing with other pets.

Symptoms of Ear Hematomas in Dogs & Cats

An ear hematoma will cause part of the ear to appear puffy and swollen and may feel warm to the touch. It’s likely to get bigger quickly because the ear is filled with blood, and is probably most visible from the inner side of the ear. An ear that normally stands up may stick out to the side or fold down.

Your pet might not want his ear to be touched because it is probably uncomfortable. He might try to make it feel better by rubbing or scratching it but that could make it worse by breaking more blood vessels and allowing more blood to fill the ear.

Diagnosing Ear Hematomas in Pets

Your vet may visually inspect the ear canal to look for foreign objects. He’ll also look for signs of infection, like pus, redness or a waxy, brownish discharge.

Your vet will likely also perform some tests to determine the underlying cause of the hematoma:

• An allergy test to see if an allergic reaction has caused the swelling
• An ear swab to collect discharge and look for parasites under a microscope
• A biopsy and cytology to rule out a tumour
• Samples of blood and urine to test cortisol levels to rule out Cushing’s syndrome

How to Treat Your Pet's Ear Hematoma

An aural hematoma may eventually be reabsorbed into the body. While you’re waiting for that to happen, however, the issue could worsen, potentially leading to a considerable amount of scarring on the ear. There are several treatment options to consider:

Aspiration

This method involves removing the blood with a syringe. It’s relatively quick and painless. To prevent the ear from filling back up, your vet may give a steroid shot to help the ear heal.

Surgery

Surgery involves making an incision to drain the blood and then the entire area that was swollen is stitched through the ear. Each one is stitched in the shape of an L to increase the surface area for healing and they’re evenly spaced apart. It looks kind of like a quilt and it stops the blood from pooling.

Your vet may decide to suture buttons to the ear. Yep, plain old shirt buttons! 

The buttons on either side push against each other to heal the cartilage. They take up more surface area so they require fewer stitches.

Drainage

This method involves making a small incision and using stitches to secure a draining tube to the ear. The other end of the tube connects to a container the size of a lime, which catches the blood.

The blood drains and the ear heals back together slowly, over the course of a few weeks. Your vet may need to teach you how to empty the container and reattach it to the tube.

For this method to be successful, your pet would have to tolerate something attached to his ear for that long so he might need to wear a surgical collar that would prevent him from scratching and pulling on it. This may be especially useful for dogs with long, floppy ears.

Medication

Some pets can’t be given anesthesia because they’re at high risk for complications. Pets with low blood pressure or a slow heart rate could die on the table because, for them, the anesthesia could dangerously enhance these issues. Tests can be done in advance to determine if your pet is a good candidate for surgery.

For pets who can’t be given anesthesia, your vet may prescribe an oral corticosteroid to help minimize inflammation and speed up healing while the hematoma is reabsorbed into the body.

Leeches

This is a less common but naturally beneficial method. Leeches are placed on top of the hematoma to suck out the blood while the cartilage slowly heals back together.

Leeches use their mouths to inject their natural numbing chemical and anticoagulant before they start sucking. The numbing agent eliminates the need for a local anesthetic. The anticoagulant can help break up tiny clots so the leeches can suck the blood out more efficiently.

This method may take days or weeks, depending on the size of the hematoma.

The leeches are used only once before they’re retired and live out the rest of their days swimming around in a bowl of water. Nice work if you can get it!

Preventing Ear Hematomas

Part of treating the hematoma is preventing it from happening again. If you simply drain the blood, there is still space where blood may continue to pool. This is why vets use stitches, corticosteroids or suction to heal the ear back together and prevent the blood from collecting in the same place.

To prevent an aural hematoma, you have to prevent the underlying cause:

• If you notice that your pet is scratching his ear excessively, take him to the vet for an allergy test
• Have your vet check for yeast and external parasites annually
• Ask your vet about ways to prevent external parasites, such as ear mites, fleas and ticks
• Routinely clean and dry your pet’s ears to prevent wax buildup and infection

If you notice your pet is shaking his head or scratching his ear more often than normal, he may need to see the vet. The sooner you can find out what the problem is, the better chance you’ll have to prevent an ear hematoma from occurring.