Abstract
A number of oceanaria are involved with rehabilitation programs that result in the presentation of stranded and injured animals with traumatic wounds. Basic wound care techniques that are taught in medical schools incorporate the utilization of bandaging materials to enhance wound healing and protect damaged or healing tissues. There are numerous wound care systems that have been developed which incorporate basic foundational principles but they are often geared toward terrestrial animals.
The approaches to wound care varies tremendously between clinicians with the amount of effort expended determined by a number of factors including exposure in veterinary school, comfort with bandaging and support techniques and attention to detail in regard to wound response. While it is recognized that many wounds can close on their own there are many benefits to proper wound care including faster healing rates, less antibiotic use, less scarring, less loss of function, and fewer complications.
Wound care can be subdivided into 4 main areas. The first is wound debridement, which incorporates the removal of dead or necrotic tissue. At this point the wound is also cleansed of any foreign material including residue from dressings. The second basic component is maintenance of a moist environment. One of the most common misunderstandings in the philosophy of the use of dressings and bandages regards the subject of moisture in the wound. An abbreviated guideline that is often partially remembered from veterinary school for terrestrial animals "if it is moist make it dry and it is dry keep it moist" often leads to poor or frustrating results in wound care. In the human and terrestrial medical fields it has long been recognized that a moist wound environment promotes re-epithelization and healing while exposure to the surrounding environment dries the wound surface and may impede the healing process. It is recognized that the marine animal is exposed to a surrounding "wet" environment, but it may be no less harsh than an air interface with a terrestrial animal wound. The hypertonic saline environment can also slow wound healing resulting in local desiccation of exposed tissues. The contact water in the rehabilitation environment can also serve as a source of new infectious agents contaminating the wound with new organisms and complicating the wound healing process.
Since the variability of wound presentation is very wide where trauma is involved there are a number of bandaging choices that may be considered, with some of these showing good application in the marine environment. Gauze dressings, used in a classic wet to moist configuration, are often not as useful in the marine environment because of their permeable nature and their tendency to pull beneficial ointments away from the wound. Other potential choices include polyvinyl dressings, hydrocolloid dressings, and absorptive dressings. Polyvinyl dressings such as Tegaderm® show the most direct application with sea turtles and manatees.
They provide a water resistant barrier that is impermeable to bacteria and other contaminants, as well as helping to control the tonicity of the local environment. These dressings can also be used to contain useful antibacterial ointments and pastes, or in combination with other dressings such as calcium alginate compounds.
The aquatic clinician is further challenged in the application of these materials as a result of the constant water interface. One adaptation in marine animals is in the use of anchoring techniques such as superglue, which is applied to the dressing edge to maintain it integrity with the skin and to enhance the waterproofing capacity. This approach has worked well with sea turtles and appears to hold some promise with manatees in protecting chest wounds.
The third principle of wound care is preventing further injury. Another anchoring technique is the use of flotation jackets in manatees and cetaceans as a secondary protection layer for a bandage. This technique has also been used to provide a pressure bandage in manatees for localized areas of subcutaneous emphysema and support for broken ribs. Bandaging techniques in sea turtles may combine wound care approaches with splinting techniques for plastron fractures and shell fracture realignment. Elastikon® has been used to protect wound dressings in turtles by placing a layer over the Tegaderm® bandage in delicate tissue locations. The Elastikon® is impregnated with lines of superglue, which when dry, form a lattice of extra support for the more delicate Tegaderm®. Superglue reinforced Elastikon® may also be used in combination with body wraps in sea turtles for plastron injuries.
The fourth principle of wound care is to provide adequate substrate for healing. The nutritional needs of an animal with wounds can increase greatly due to the extent of the wound or the lack of normal food intake. Nutritional intake must be maintained during the healing process and if necessary the animal should be supplemented with additional caloric intake or by force feeding. These individuals should be weighed a minimum of once a week to gauge their nutritional capacity. Thin animals should be assumed to require supplementation. The wound itself can be used visually as a gauge for nutritional requirements. Granulation will be delayed if the animal is not receiving adequate caloric intake and the rate of granulation will increase when the intake is increased. In otherwise healthy individuals, wounds should begin granulating within a 10 day period and if granulation is not present the nutritional needs of the animal should be quickly reassessed. Young animals may show less granulation as a result of a poor weight gain rather than a result of a weight loss as seen in adults.
Tegaderm®, 3M Center, St. Paul ,MN., 55144
Elastikon® , Johnson and Johnson, Arlington, TX., 76004