In the soft tissue surgery department at Northwest Surgeons, we are often required to assess and treat patients with chronic, delayed healing or extensive wound beds. Open wound management is often used as an initial form of treatment and indeed this form of management can often result in complete healing if we nourish the wound bed and support the surrounding tissues. We generally assume that all chronic and extensive wounds are contaminated to some degree, so open wound management is always the best option initially to encourage healing and prevent an inevitable wound breakdown ( dehiscence ) if a wound is closed too quickly by surgery.
Each wound bed and the surrounding tissue must be carefully evaluated :
• Blood supply : Is the surrounding tissue warm and does it bleed when dead and devitalized tissue is surgically debrided (scraped away) – is there an impression that there is a blood supply to the wound bed for healing to be effective?
• Contamination of the wound bed : dirt, blood clots, sloughy surface tissue – this needs to be removed by an initial surgical debridement and then lavage (flushing) sterile water or saline (do not use saline if using silver dressings, this will precipitate out the silver rendering it ineffective to the wound bed). Lavage removes lose debris and reduces bacterial numbers.
• Infection of the wound bed: We will often take a swab for bacterial culture and antibiotic sensitivity during the initial assessment of the wound bed and may periodically check the bacterial status of the wound bed during the phase of open wound management if we have concerns that the wound has become infected.
• Antibiotics – nowadays we very rarely give long courses of oral antibiotics for wound infections – giving long courses of systemic antibiotics will increase the likelihood of the patient developing a resistant bacterial infection at the wound bed. More commonly, we use antimicrobial products that are applied directly to the wound bed. These are discussed in a bit more detail below.
• Location of wound bed: We need to devise a method of covering the wound bed to provide the most ideal healing environment and also to provide protection. We also need to consider the nature of each individual patient , how active they are and devise a dressing that will work on a day to day basis. Often wounds are located in awkward areas of the body such as the side of the chest, top of a tail or side of a leg. For these awkward locations a tie-over dressing may just be the answer – read on….
Tie – over dressings are a useful way for securing wound products to a wound bed without having to encompass vast amounts of a patients body. A ring of suture loops are sewn around the circumference of the wound bed. Suitable contact products are chosen for that particular wound, for instance a hydrating sterile gel. This is applied to the wound bed, then an absorbent foam is cut to the desired shape and place on top of the contact product. Swabs are applied on top of the foam to add some bulk to the dressing and then nylon tape is used to link the suture loops together in a crisscross fashion to secure the bundle of dressing materials beneath. The end result represents a ‘parcel’, the patients can often have the dressing materials renewed without any sedation as they feel very comfortable with this style of dressing.
More on the contact products : Nowadays, we have a number of excellent substances available for our veterinary patients with wound beds that are being treated by open wound management – I will mention a few of the most common ones we use at Northwest Surgeons.
Hydrogels are excellent at providing moisture to encourage the ongoing removal (debridement) of the devitalized tissue, encourage the in growth of new cells to fill (granulate) and support the formation of a new skin (epithelialisation).
Silver was used by the Greeks and Romans for its perceived health benefits and indeed they were wise to do so. Silver can be very effective against a number of bacteria, fungi and yeasts. The silver is now formulated into user friendly sheets which can be shaped to the wound bed and allows the nanocrystalline silver particles to slowly diffuse into the wound bed over 3-7 days. Another ancient remedy that has come back into vogue is the use of honey.
Manuka honey is antibacterial, removes devitalized tissue, reduces odour, stimulates healing, provides a moist wound environment and reduces inflammation and pain. This special medical grade honey is available as a gel or impregnated into a mesh (tulle). Why not use ordinary honey that we eat? Most honey purchased is pasteurised so is not likely to contain any contaminants to a wound bed but the process of pasteurisation inactivates the glucose oxidase enzyme that provides so much of the beneficial effect in wound management.
Antimicrobial foam dressings impregnated with polyhexamethylene biguanide are proving to be a very useful dressing – not only do they perform the primary function of absorption but they have the added value of reducing bacterial colonies and preventing bacteria penetrating the dressing.
Open wound management is challenging but is an incredibly rewarding part of our work at Northwest Surgeons. Yes, these cases take a while to heal but the end result for the pets under our care is fantastic.Full Article >