Tuesday, March 20, 2012

From The Case Files: From A Swelling To Necrosis In Days

By Dr. Jonathan Mitelman, DVM, and Barbara Kelly

When Brutus, a 22-month-old Great Dane, arrived as an emergency patient at VETSToronto at the Kingston Road Animal Hospital, he presented with a wound to his left forelimb unlike anything Dr. Jonathan Mitelman had ever seen.

The affected area was 10 inches long by seven inches wide (25 cm x 18 cm), wrapping around the dog's leg.

It was necrotic, foul smelling, oozing pus and the swelling had reached his paw.

Fortunately, he was still able to walk.

Several days earlier, the dog's owner had taken him to a local veterinary clinic for what was then a small swollen area on the leg and an elevated temperature. 

Preparation for surgery: note the difference between healthy appearing skin,
inflamed pink tissue and the necrotic black eshar.

Radiographs were taken and antibiotics administered.

When the swelling began to travel, and the skin began to blacken, it was recommended to the owner that he should seek another consult at a veterinary referral hospital. Through connections with the Great Dane meet-up group, Brutus was then brought to VETSToronto.

Dr. Mitelman called in his partner, Dr. Morris Samson, to examine Brutus and consult on the case. Efforts were made to discover the source of the wound.

Was it trauma, or an infectious agent?

The investigation process lead to the following possible causes: A puncture wound from a bite or foreign object, or contact exposure from a topical substance. In both cases the owner deemed these to be highly unlikely.

The next step was to look towards less common possibilities including:
  • Snake bites or tick borne diseases (the family had recently been to the southern United States).
  • Fungal disease
  • A blood clotting issue affecting blood supply to the region.
  • MRSA (Methicillan-resistant staphylococcus Aureus) or pathogenic bacteria-like necrotizing fasciitis.
Additional radiographs were taken to assess the chest and abdomen. Blood work (including clotting profiles and tick-born disease titres), cultures and tissue pathology were done.

The doctors also reviewed the case with another senior veterinarian and surgeon who provided a supporting opinion.

Brutus was lethargic, had diminished appetite, losing weight and was jaundiced. 

There was a concern he was becoming septic (a life-threatening condition where bacteria and toxins enter into circulation and render the patient cardio-vascularly unstable.

Due to the geographic spread of the wound, Drs. Mitelman and Samson realized immediate surgical intervention was required. 

Treatment was necessary now, the search for the cause would follow.

Two surgical options were possible.

The first would be to debride (mechanically remove tissue) the big, necrotic wound with the risk that the dog could still become septic. The second was amputation of the foreleg,  certainly not optimal in a 165 pound Great Dane.

A decision to debride the wound was made and Brutus was taken into surgery that night. 

The necrotic eshar was removed leaving some dead extensor tendons (white), thrombosed dead cephalic veins (black) and necrotic fat. Note the dull appearance of unhealthy tissue.

It was necessary to move quickly as the chance of becoming septic was high.

Debriding the wound was done using scalpel and scissors. It was necessary to remove the dead tissue. The goal was to keep the pink and excise beyond healthy to the level of fresh bleeding tissue.

Brutus was left with partially intact tendons, lots of exposed flesh and big puffy toes.

The area was disinfected with sterile saline and non-stinging betadine (surgical iodine – the key to disinfecting a wound such as this is to only use solutions that will not irritate the tissue).

This entire process took more than an hour to complete.

Next step was to help shed dying tissue, to induce granulation and assist wound healing.

What did the doctors use? Sugar.

Sugar osmotically draws to the surface fluid from surrounding and deeper tissue and bacteria, thereby non-invasively killing the unwanted bacteria.

The wound was packed with the sugar and covered with non-stick bandages that would allow for all of the blood, pus and dead tissue to be drawn away from it. Dressings were changed two- to three-times daily for a week and after this period, daily bandage changes were all that was needed.

Oral antibiotics were continued and tramadol prescribed for the pain as needed.

After three days at VETSToronto Brutus was able to go home. Although he had never lost the ability to walk throughout the infection, he was certainly visibly more comfortable now.

His owners were shown how to clean and change the bandages and weekly follow ups, including culture swabs, are done at the clinic.

The wound is expected to take several months to heal. 

The hope is the body might be able to heal on its own, save the protective bandaging.

In just under a month the wound filled in and is reduced to less than half its original size.

However, it is possible that future skin grafts will be necessary for tissue reconstruction should insufficient wound reduction and excessive tissue granulation occur. This could consist of advancing skin from higher up on the limb and sliding it down into place or taking skin from elsewhere on the dog's body.

A third option would be an allograft that is chemically prepared tissue from another species, attached to the limb, and used to promote tissue re-growth.

Brutus’ wound is healing so well to date that Dr. Mitelman is hopeful skin grafts will not be required.

The cause of the wound has yet to be determined. The pathology report indicated beta hemolytic growth and extensive necrosis but still no conclusive etiology.

Lessons learned:
  1. If there is swelling, it is best to find out early what is causing it. After awhile, anything can look like everything. After four days on the antibiotic, and the extensive spread of the necrotic area, the pathology was unable to provide the doctors with a conclusive cause of the wound.
  2. If it is dead, take it out. Dead tissue holds toxins in, and poisons the healthy tissue.
  3. Advice for wound management includes keeping it clean, understanding that healthy tissue is pink and may bleed if rubbed.
  4. Also, do not apply tension, use caution when bandaging as it can have a tendency to constrict and choke off blood supply.
  5. Do no put anything into an open wound that you would not put into your own eye. It is best to check with a vet before applying any over the counter topical medications.


  1. Terrifying! So glad he didn't lose his leg. One of my trainer's search and rescue dogs just lost a foreleg two weeks ago. He is adjusting well to being a tripod but it's never a good thing to have to do.

    1. Really really scary. So glad his leg is healing. So sorry about your trainer's dog :-( What happened?

    2. He had a bone shard in his elbow (don't know if it was from injury or congenital) but was sound on it. He is not quite a year old but had been sound on this diagnosed issue for a while. Lately when working, he took a funny step and went 3-legged lame on it; turns out he messed it up more. The options were an expensive, risky surgery where he would most likely lose the leg later or to take the leg now. She decided to just take the leg and save all the drama. (She is also a vet tech.) I definitely support her decision. He is doing really well already and I'd say is nearly normal on 3 legs after only 2 weeks.

    3. Oh, wow, two options and each of the sucked! Make sense to go with the one where it's probably going to end up anyway.

      Yes, many tri-pod dogs do just fine, as if nothing was wrong.

  2. Possible spider bite?

  3. We are now 4 weeks post-debridement for our 9 1/2 year old Boxer who was bit by a brown recluse 10 weeks ago. It has been a long process but she is healing.

    1. Such bites can be so nasty. Glad she is healing.

  4. I'm reading this article because we found out today that our newest family member, Lanie, has necrotic tissue due to an infected incision from her spaying. I feel terrible that I didn't realize that the incision was infected. The veterinarian told me today that they will have to open her back up to remove the dead tissue and then stitch her back up. I'm so worried about her and just feel like a terrible pet owner for not realizing how bad it was. :(

    1. I'm sorry about Lanie and about how you feel. They will do whatever she needs for her. Thinking of you.