Otohematomas in cats are characterized by the filling of blood and other secretions in the space between the skin and cartilage of the pinna (the outer part of the ear, also known as pinna). These wounds can appear in cats that scratch their ears too hard or shake their heads. If you suspect a hematoma in your animal, you will need to learn more about the two treatment options: surgery and the use of medication.
Steps
Part 1 of 4: Identifying and Understanding Cat Ear Bruises

Step 1. Know when swelling or tenderness may indicate a bruise on the ear
When raised, it should be no more than 7 to 10 cm thick and will be shaped like a concave cone; after an injury, the ear takes on the appearance of a large blood bubble. The pinna may feel sensitive and warm; when applying pressure to the site, it will appear that there is a “liquid” in the site.

Step 2. Look out for the condition called “cauliflower ear” or ear bruise
Not treating the lesion after five to seven days will make the pinna look very thick, wrinkled, and diminished in size; it is a consequence of the reabsorption of the fluid that remains after blood clotting. There is also a chance that the ear has atrophied, blocking entry to the ear canal, decreasing air circulation and facilitating ear infections.

Step 3. Know what causes otohematoma
The cat's ear is supported by a “net” of rigid cartilage, lined with skin on both sides, which is fed by small blood vessels that also connect it to the cartilage. When cats scratch their ears, the skin can detach from the cartilage, breaking the spider veins and causing blood to deposit in the space between the skin and the cartilage, in other words, a bruise.
Bleeding should resolve without interference and will stop as soon as pressure builds up in the hematoma, which compresses the blood vessels

Step 4. Review treatment options for ear damage
There are two ways to promote otohematoma recovery: surgery and use of medication. The first guarantees the cat's complete recovery, but it will need anesthesia and will have to wear an Elizabethan collar for two to three weeks. The second offers only a 50% chance of success, but it can be repeated if it doesn't work at first.
The surgery will be more expensive, but if the therapy has to be repeated, the cost could end up being higher
Part 2 of 4: Correcting an ear bruise with surgery

Step 1. Prepare the animal for the anesthesia and surgical procedure
Due to the use of general anesthesia, the cat must fast for the night before the operation.
- Once he is admitted to the veterinary clinic, an injection will be given to relieve the pain and sedate the cat.
- After about 20 minutes, when the pet is already sedated, the general anesthetic will be applied, while the hairs on his pinna can be shaved or pinned so as not to interfere with the procedure.

Step 2. Understand what surgery is like
The entire environment is sterilized before starting, and the goal will be to make a 2-3 cm incision on the inside of the pinna, allowing blood to flow out.
The veterinarian will wash the empty “pocket” between the skin and cartilage to remove blood clots and make the skin “stick” back to the cartilage so that the bruise does not appear again

Step 3. After the procedure, place an Elizabethan collar on the cat
With it, the animal will not be able to move, scratch or scratch the sutures; otherwise, he could injure himself and even rip off his own ear.

Step 4. Feed the cat light food
White fish and chicken at night after anesthesia will help fight nausea.
- Don't be scared: it's normal for the pet to be very sleepy in the 24 hours after sedation.
- After the operation, it is recommended to keep it indoors, in a warm environment.

Step 5. Stitches should remain for two to three weeks
During this period, scar tissue will form and will help to "glue" the skin to the cartilage. Return to the vet after this time to have the sutures removed, allowing the cat to return to normal life.

Step 6. Take good care so that infections do not occur in the region that was operated on
The veterinarian may indicate a gentle cleansing of the spot with the stitches using saline water (one teaspoon of salt mixed with about 550 ml of pre-boiled water) once a day.
Thus, it will be possible to remove pus and bacteria that accumulate on the surface of the skin, reducing the chance of contamination
Part 3 of 4: Cleaning an Otohematoma through Veterinary Treatments

Step 1. Take the cat to the veterinarian, who will drain the contents of the lesion
Blood and secretions from the wound will be aspirated, and a small amount of injectable steroid will be given inside. This works best on quieter cats.
- An anesthetic cream (such as EMLA) will be applied prior to needle penetration.
- Cats that make a mess and make drainage impossible will have to be sedated. In this case, it is important to reevaluate the surgical option, as you will spend more to sedate him, minimizing one of the advantages of the therapies.

Step 2. Understand how aspiration is performed
A veterinarian will immobilize the cat in a sitting position and disinfect the ear, while the syringe will be prepared to be inserted into the most swollen point on the ear. Through suction, the blood will be aspirated as much as possible; soon after, another syringe will be introduced, containing a steroid, in order to deposit it in the “pouch” that has formed.

Step 3. Schedule a return to the vet
The cat will not need to wear the Elizabethan collar and will be able to have its normal routine without any special care after the procedure. It is important, however, to return to the clinic after seven days.
About 50% of the bruises in the pinna will be filled with blood again. If this happens to your pet, it will be necessary to define whether it will try to aspirate the contents again, or will submit it to surgery. Just waiting and watching will make it a “cauliflower” type
Part 4 of 4: Preventing New Otohaematomas

Step 1. Check the cat's ears for signs of infection frequently
Most of the time, these injuries occur when he scratches the spot or shakes his head sharply. It is also common for infections or parasites, such as fleas or mites, to cause the appearance of ear hematoma. To reduce the risk of such injuries, occasionally look for signs of contamination in the cat's ear.
- Included are unpleasant odors that originate in the ears, reddening of the skin compared to the other ear, and discharge from the ear. This secretion may have a thick, dark brown wax - usually associated with mites or fungal infections - or a creamy, yellow, purulent material (which signals bacterial contamination).
- Anyway, it is essential to take the cat to the veterinarian for the correct treatment.

Step 2. Learn to control parasite contamination
The use of medications, such as dewormers, is recommended to prevent such pests.
- Ivermectin family remedies, such as Revolution, contain selamectin, which not only fights fleas but also mites. The prescribed drug should be applied to the cat's neck region once a month and every month.
- Nodding and shaking the head is the most common result of the irritation associated with ear mite infection. The regular application of a drug with selamectin should exterminate the pests, besides preventing the recurrence of infections.