initially cut in the centre to allow the VS to monitor the wound without disturbing the dressing. However, this modification raised concerns about contamination from dirt or bacteria entering the bandage.
Maddie was extremely willing and mobile but the weakness in her hindlimbs meant she would fall down on to her elbows, and this contributed to the tissue damage in this area.
The owners were advised to keep Maddie rested during the healing process, but they felt it unfair to continuously restrict her when she had previously been such a willing and active dog, and she lived with another energetic and bouncy dog. They tried to balance her mobility and rest to help reduce the pressure on her elbows, but this was difficult.
The owners and VN tried various dressings and adaptations to help protect Maddie ' s wound while also keeping her comfortable. Her quality of life remained a priority for the owners, VNs and VSs throughout the wound management period.
Wound cleaning and lavage
Following the tissue biopsy, the wound broke down 11 days later( 20 March) and was producing a yellow, sticky exudate. The area was clipped and the skin around the wound was cleaned with one part Hibiscrub( Mölnlycke) to 20 parts water. Owing to the severity of the ulcer, this dilution was chosen to prevent any complications from the use of chlorhexidine near the healthy, granulating tissue.
Hibiscrub is an antibacterial cleanser used in veterinary practices. The active ingredient is chlorhexidine gluconate, a highly effective antiseptic that is very efficient at eliminating viruses, bacteria and fungi [ 7 ].
Thorough wound cleaning removes visible and microscopic debris, reducing bacterial load and the risk of complications, while allowing clearer assessment of underlying tissues. The key to effective lavage is using a large volume of a non-toxic solution.
The ideal lavage fluid should be antiseptic and nontoxic to the healing tissues. Saline( 0.9 % sodium chloride) solution is the least toxic to healing tissue, although it has no antiseptic properties. Surgical scrub agents should not be used because the detergent components damage tissue. Dilute antiseptics can be used safely [ 8 ].
It is important to ensure that the delicate granulation tissue is not traumatised in the process of cleaning a wound. Lavage is the most effective way to clean a wound, but should be delivered under appropriate pressure. Excessive pressure can cause adverse effects by driving debris deeper into the healthy tissue and destroying the granulation tissue.
Low-pressure systems, such as a bulb syringe or the careful use of a 20 ml syringe, are adequate methods. Higher pressures are used with dirty or contaminated wounds. A recommended lavage system delivering 48 – 55 kPa( 7 – 8 psi) of pressure can be fashioned with a 35 ml syringe and a 19 G needle [ 8 ].
Silver dressing
On 24 March, a silver dressing was applied, then layered with Soffban, conforming bandage and vet wrap from the carpus to the shoulder. Adhesive dressing secured the bandage to prevent slipping. The foot was intentionally left without a bandage to aid Maddie ' s proprioception and avoid the dressing becoming wet when she was outdoors.
Silver in its metallic state is inert. When it interacts with moisture from the skin and with fluid from a wound, silver is ionised and has antimicrobial effects that are directly related to the amount and rate of silver released [ 9 ]. The ionised silver moiety is highly reactive, binding to tissue proteins and causing structural changes in bacterial cell walls and intracellular and nuclear membranes, ultimately leading to distortion and loss of viability of the bacterial cells. Additionally, the silver ion has further bacteriostatic properties, binding to and denaturing bacterial DNA and RNA, thereby inhibiting bacterial replication [ 10 ].
A silver alginate dressing, Algicell™ Ag( Derma Sciences, Inc.) was used in this case, as it behaves as a bacterial barrier with controlled sustained silver release and has a reported kill rate of 99.99 %, 99.91 % and 97.46 % at days 1, 3 and 5 of challenge, respectively, for Staphylococcus aureus. The dressing is indicated for diabetic ulcers, leg ulcers, pressure ulcers, donor sites, and traumatic and surgical wounds [ 10 ].
By 28 April, there was evidence of granulation tissue but bone was visible at the wound site, so the dressing regime was changed to include Intrasite( Smith and Nephew) hydrogel dressings and Allevyn( Millpledge) non-adhesive foam dressings.
Hydrogel dressing
Hydrogel dressings, such as Intrasite gel, maintain a warm, moist wound environment, promoting faster healing and providing protection against infection [ 11 ].
Hydrogels are composed of approximately 90 % water within hydrophilic polymers; they regulate moisture, facilitate painless debridement and support granulation, making them suitable for wounds with light to moderate exudate. Their cooling effect also alleviates pain. However, it is important to note that excessive moisture can cause maceration and increase the infection risk, if not managed appropriately [ 11 ].
40 Veterinary Nursing Journal