Wound care has become very complex. However, by adhering to the important fundamentals of wound examination, ongoing reassessment, debridement and promotion of tissue substructure and granulation tissue, and application of various closure techniques, healing can be achieved in most patients and accelerated in many.
Once infection and vascular insufficiency have been addressed, purely neurologic wounds should heal promptly and provide good wound care and unloading.
Debridement removes inactivated tissue, bioburden and senescent cells, and promotes healing through bleeding. By debriding a wound, a chronic, slow-healing wound can be transformed into a healthier, more acute wound. When debriding a wound, it is important to remove all necrotic and nonviable tissue. Surgeons should not be concerned about defects caused by the initial debridement because removal of this tissue is essential if closure is to be achieved. Most wounds require serial debridement.
Debridement Sponge Brush
There are five methods of wound debridement: mechanical, autolytic, enzymatic, surgical, and biosurgical. Mechanical debridement is no longer the primary method. It involves using wet gauze dressings, allowing them to dry, and then removing the dry gauze, thereby "tearing off" the surface layer (wet to dry dressing). Self-soluble debridement is achieved by covering the wound with a closed dressing and allowing the wound's proteolytic enzymes to dissolve fibrotic or necrotic tissue. This is rarely recommended due to the risk of infection and the availability of better methods. Enzyme debridement uses an emulsion such as collagenase to remove inactivated tissue.
Surgical debridement is the most common and effective method. It can be accomplished simply by using a scalpel or a newer modality such as the waterjet, which allows for precise debridement depths. It is typically performed in an operating room setting. Another recent development in wound debridement involves ultrasound.
Local wound management reduces the risk of infection and maximizes functional and aesthetic outcomes. Early wound debridement is the most important treatment to prevent infection and zoonotic diseases such as rabies. Scrub the intact skin around the dirty wound with a sponge and 1% povidone-iodine or 2% chlorhexidine gluconate solution.
Medical Instrument Cleaning Brush
Alternatively, a dilute povidone iodine solution can be used for irrigation, as long as the wound is rinsed with saline or water afterwards. Gently clean dirty or deactivated tissue-containing wounds with gauze or porous sponges and debride thoroughly. Optimal wound management may require treatment in the operating room under general or regional anesthesia.
Options for wound repair include primary, delayed primary, and secondary closure. The anatomic location of the bite, the source of the bite, and the type of injury determine the most appropriate approach. Primary closure is indicated for head and neck wounds initially seen within 24 hours of the bite, is important for aesthetic results and has a low rate of infection. Primary closure can also be used for low-risk wounds of the arms, legs, and trunk if seen within 6 to 12 hours of the bite. Severe human bites and avulsion wounds of the face requiring flaps have been successfully repaired by primary closure; however, this technique is controversial.
Wounds prone to infection, such as those initially more than 24 hours after the bite (or more than 6 hours if ear or nasal cartilage is involved), are covered with a wet dressing and initial closure is delayed after 3 to 5 days. Puncture wounds have an increased incidence of infection and are not closed with sutures.
Deep irrigation and extensive excision of small puncture wounds have not been shown to be beneficial. However, larger puncture wounds usually benefit from irrigation and debridement. Secondary treatment usually results in unacceptable scarring in cosmetically sensitive areas. Clinicians should be alert to severe dog bites that may have extensive areas of destruction caused by large canine teeth. These wounds require surgical intervention under general or regional anesthesia.
Bites involving the hand or foot have a greater chance of becoming infected and remaining open. The primary goal in repairing hand bites is to maximize functional outcome. Even with adequate treatment, approximately one-third of all dog bites to the hand become infected. Secondary treatment is recommended for most hand lacerations. After thorough exploration, irrigation, and debridement, the hand is immobilized, wrapped in a heavy dressing, and elevated. Although high-quality data are limited, prophylactic empiric antibiotics may be necessary in these settings.
