In nearly all cases, open wounds should be bandaged to protect the wound from contamination and support the wound while it heals. In most cases, mechanical debridement of the wound bed is desired in the early stages of wound healing, prior to the formation of granulation tissue. In a compromised patient where anesthesia and surgical debridement are not possible, moist wound healing provides a safe means of wound debridement until the patient is more stable.
Primary Layer
Moist wound healing is the standard of care for wound management. Wet-to-dry bandages (adherent) are no longer recommended due to the indiscriminate debridement which compromises wound healing.
If non-surgical debridement is needed during early wound care (in presence of contamination and infection), hyperosmotic agents such as hypertonic saline dressings or honey can be used.
The current standard of care for open wound management is moisture retentive dressings (MRD). They facilitate debridement, granulation tissue formation and epithelialization and are applied directly to the wound.
Select the most appropriate MRD based on anticipated exudate production. See Table 2 for basic dressing guidelines.
Use aseptic technique when handling the MRD. Prior to placing the MRD on the wound bed, ensure that the dressing does not extend over the intact skin to prevent maceration. Consider the depth and shape of the wound when selecting the dressing.
For infected wounds, nanoparticle slow-release, silver-impregnated dressings and ionic silver-impregnated dressings show superior effectiveness. The hydrophilic silver-impregnated dressings release ionic silver into the gel that is produced at the wound exudate-dressing interface which provides consistent antimicrobial activity against a range of aerobic and anaerobic bacteria, including antibiotic-resistant strains, yeasts and filamentous fungi. If these dressings are not available, a non-adherent pad with antibiotic ointment (e.g. a combination of bacitracin zinc, neomycin sulfate, and polymyxin B sulfate) can be used on most wounds.
Secondary Layer
Apply a secondary layer over a primary layer. Most commonly, rolled cast padding or roll cotton is used to provide support. Splints can be included in the secondary layer, if used.
Tertiary Layer
Apply a tertiary layer, typically consisting of a non-adherent conforming bandage, adhesive bandage, or both. This layer holds the dressing and secondary layer in place, provides additional support, and provides more durable protection of the underlying layers. In most cases, the tertiary layer is applied just tight enough to hold the bandage in place, and without compression.
A tie over bandage (see Figure 2 below) should be used in locations that are difficult to place a bandage, such as the inguinal area, dorsum, hip and flank. Routine bandages placed in these areas typically slip off and fail to protect the wound. A tie over bandage consists of the same layers of bandage material placed within and over the wound.
Multiple suture loops are placed around the periphery of the wound in the skin, evenly spaced around the wound, using large (2-0 or larger) monofilament suture material (preferably non-absorbable). The bandage over the wound is then covered with a portion of impermeable drape or similar material. The entire bandage is then secured using umbilical tape or similar material laced through the suture loops in a shoelace-type crossover pattern. Ties of surgical masks are a good substitute if umbilical tape is not available. The ties should be sufficiently tight to hold the bandage in place, with mild tension on the suture loops. The covering layer should be snug over the top of the underlying layers. Adhesive material, such as Ioban™, can be used to secure tie over bandages in place of suture loops and ties.
Change bandages at least once daily. More frequent bandage changes may be necessary if the wound has heavy discharge, or the bandage becomes soiled or partially removed by the MWD. Once wound discharge is reduced and a healthy granulation bed has formed, bandage changes become less frequent, generally every 2-3 days.
Any MWD with a bandage applied must be prevented from chewing at the bandage. An e-collar or plastic bucket with the bottom cut out can be used to prevent self-trauma and is attached to the dog’s collar as an effective prevention practice.
NEGATIVE PRESSURE WOUND THERAPY
Negative pressure wound therapy (NPWT) has proven a viable treatment modality for wounds in dogs. Consultation with a veterinary surgeon will ensure appropriate application and management. Heavy sedation of the MWD to prevent disruption of the dressing is sometimes required. See Figure 3 and Figure 4. In most cases, application of NPWT can be delayed until the MWD is medically evacuated to a Role 3 veterinary facility or out of theater for long-term care. If NPWT is applied, -125 mmHg on a continuous mode is the typical setting for open, granulating wounds
