Dog Ear Hematoma: Causes, Symptoms, Treatment and Prognosis

Medically reviewed by: Kinga Wojtczak, Doctor of Veterinary Medicine, specialist in canine and feline diseases

Our four-legged friends' ears are very sensitive and delicate. The pinna (ear flap) is a thin piece of cartilage covered with skin that has a rich blood supply; its main job is to protect the delicate ear canal and to amplify incoming sounds. Ears often tell us about the emotions a dog is feeling—held upright, they signal alertness; held low, unease; spread out to the sides, relaxation.

The ear usually sticks out from the skull, which makes it especially vulnerable to all kinds of injuries—it is easily grabbed during a fight or knocked during play. Such injuries very easily cause bleeding within the pinna—as I mentioned, it has a very rich blood supply. Often this ends in a small bruise, but in some cases it results in a dog ear hematoma (aural hematoma, a blood-filled swelling of the ear flap).

Causes of ear hematomas in dogs

There are several theories about what causes aural hematomas in dogs. It used to be widely held that a hematoma results from trauma—a blow, a bite or scratching damages the blood vessels, and blood leaks out of them under the skin. Today, however, hematomas are thought to result from dermatological disorders—after all, in a healthy dog the blood vessels are very elastic and do not rupture from injuries.

In many cases, it is a good idea to look deeper for the cause and find out why the blood vessels in the pinna have become so fragile and delicate.

Predisposing factors

As I mentioned, dogs with dermatological problems are predisposed to aural hematomas. We expect to see aural hematomas in dogs with inflammation of the ear canal (otitis externa) and in dogs with a severe, generalized allergy that causes skin lesions around the head. A common cause of aural hematomas in dogs is the sarcoptic mange mite—this parasite causes intense itching and inflammation of the affected area. Bacterial infections and abscesses around the ear may also predispose a dog to bleeding within the pinna.

Dogs at particular risk of aural hematomas include all breeds with large, drooping ears:

• Basset Hounds,
• Beagle,
• setters.

Dogs suffering from the conditions I listed above develop aural hematomas especially often. But it also happens in healthy, lively and energetic dogs that frequently get injured.

Dog ear hematoma: clinical signs

What usually worries the owner is the strange look of the ear—it may be floppy, drooping, or sticking out in a different direction than the other ear. The area around the ear is often tender, swollen and much warmer than the rest of the dog's body. The ear flap itself resembles a small fluid-filled cushion—you can feel the swelling and the blood collected inside. The dog may be restless and show signs of itching, but further scratching of the ear will only make matters worse.

Diagnosis

The clinical signs—enlargement of the pinna, its swelling and tenderness of the area—are so characteristic that additional tests are usually not needed to confirm the diagnosis. When the pinna is very severely swollen and the hematoma is very tense and firm, it is a good idea to perform a quick ultrasound to make sure that the contents of the hematoma are fluid and fairly uniform—this makes it possible to rule out a possible tumor (neoplastic growth).

If this is not the dog's first hematoma and it regularly has problems with bleeding within the ear flaps, it is a good idea to run a basic blood test. Particular attention should be paid to the platelet count (thrombocytes, the blood cells responsible for clotting). It is also a good idea to check the clotting time to find out whether the blood clots normally. Many diseases cause clotting disorders (ranging from ehrlichiosis to rat poison ingestion), and their first sign is the appearance of petechiae, hematomas and bleeding, so it is a good idea to carry out a somewhat more detailed workup when the condition recurs.

Your pet's health must be checked. As I mentioned, one of the theories explaining how aural hematomas form says that the hematoma is only a symptom and that you should always dig a little deeper to find its cause. During the visit to the veterinarian, it is a good idea to make sure that the dog does not have inflammation of the ear canal and that there is no foreign body in it (for example, a foxtail-type grass awn or a piece of grass), and if there are skin lesions around the ear, samples should be collected for further testing, the cause of the lesions determined and targeted treatment started.

Dog ear hematoma: treatment

There are several treatment options for aural hematomas in dogs. If the hematoma is fresh, formed shortly before the visit, and the animal does not have a clotting disorder, nonsurgical treatment can be tried. It consists of removing the accumulated blood with a cannula. Anti-inflammatory drugs (short-acting or long-acting steroids) are injected into the hematoma cavity. In addition, the dog should receive antipruritic (anti-itch) or pain medications.

Using a protective cone (Elizabethan collar) is essential. With massive, large-volume hematomas, after they have been drained, the veterinarian may decide to apply a pressure bandage. A tube-shaped support is placed against the inner surface of the ear flap, and the ear is bandaged fairly tightly from the outside. This is not an ideal solution—an ear flap compressed this way may cause the pet discomfort, and it does not guarantee successful treatment.

With old hematomas, or when medical treatment fails and the hematoma refills once again, surgery should be considered. Here, too, there are several approaches. The most common is an S-shaped incision over the hematoma. This incision shape allows the hematoma cavity to be emptied thoroughly and then flushed of any remaining clots.

Proper closure of the hematoma cavity is important. The surgical wound itself is not closed (blood collecting around the incision must be able to drain continuously so that the hematoma does not re-form after surgery); instead, as many sutures as possible are placed through the entire hematoma cavity—the less dead space (empty space where blood can collect) there is, the better. The suture material is very often nonabsorbable monofilament, placed full-thickness, all the way through the pinna.

Some sources recommend suturing in sterile beads to compress the wound better, or inserting pieces of a cannula or IV (infusion) tubing instead of beads. The sutures are removed about 20 days after surgery. Straight incisions or excision of a piece of skin are performed much less often. After surgery, proper bandaging is also very important. The ear must be lightly compressed, while the dressing material must be absorbent enough to soak up all the blood that will drain from the wound and carry it away so that it does not collect in the ear canal.

The bandage should be changed daily to monitor healing and to respond quickly if an ear infection develops. Pain medication is very important. The use of anticoagulant gels or ointments, or of products that speed up clotting, is rather controversial.

Treating the underlying cause, however, is very important, in line with the theory that the hematoma is only a symptom. What is more, this treatment must be given before surgery, so that by the time of surgery the dog's ear canal infection has already cleared up, it is properly protected against external parasites, or, if needed, it is eating a hypoallergenic dog food, depending on the cause identified.

Preventing ear hematomas

So can aural hematomas be prevented at all? As an old Polish saying goes, "If I had known I would fall, I would have lain down." Injuries and knocks that happen during play or running fast cannot be prevented. What you can do, though, is check your pet's ears regularly for signs of infection. You can read more about ear inflammation (otitis) in our article on ear infections in dogs.

As with most diseases and conditions, acting quickly matters—the sooner a hematoma is noticed, the better the chance of avoiding surgery. Old, organized hematomas require surgery, and their treatment carries a risk of failure. The body does not like empty spaces: after the clot is removed from the pinna, if too few sutures are placed or the suture material is unsuitable, bleeding very often recurs and all the signs return.

Dog ear hematoma: prognosis

In most cases, the prognosis is favorable. Surgery gives a better chance of complete recovery, but with a fresh hematoma it is a good idea to try medical treatment before surgery. If hematomas recur regularly and always appear in the same place, the workup should be extended to make sure that all clotting mechanisms work properly and that the pet does not have mineral and vitamin deficiencies.

In that case, the dog should also be tested for tick-borne diseases, the entire ear canal should be examined thoroughly, radiographs (X-rays) of the tympanic bullae should be taken, and the pet's teeth should be examined. In extremely rare cases, ear hematomas can be caused by pain and discomfort in the mouth (and by itching caused by inflammation of the gums and cheeks).

After surgery on an old hematoma, the pinna may become slightly deformed—the ear may be thicker, and the scar that forms may cause the skin in that area to fold. This is usually only a cosmetic defect that does not interfere with the dog's normal functioning, but when the deformity makes the ear droop and close off the ear canal, particular attention should be paid to regular ear care—the dog's ears should be cleaned regularly.

Aural hematomas do not affect a dog's ability to hear, but the factors that cause them (that is, the ear canal inflammation, chronic bacterial and parasitic infections, allergies and skin infections mentioned above) can, if left untreated, cause hearing loss.

FAQ