Trauma and Wound Healing
Conventional Wound Care
Wounds are treated both locally (at the site of injury) and systemically (Ubbink 2014). One common approach to wound treatment preparation, known by the acronym TIME, involves the following (Harries 2016):
- Removal of dead Tissue, a process known as debridement
- Controlling Inflammation and Infection with antibiotics and anti-inflammatories as needed
- Maintaining Moisture balance with appropriate wound dressings
- Re-assessing wound Edges or Epithelialization to determine if new superficial skin cells are forming and the wound is healing
Debridement is the removal of foreign debris and nonliving tissue from the site of injury to improve wound closure (Steed 2004). Surgical debridement uses sharp instruments to remove dead tissue (Cardinal 2009; Attinger 2000). Enzymatic debridement involves the application of enzymes (papain, bromelain, or collagenase) to the site of injury to break down dead tissue (McCallon 2014). Autolytic debridement is similar to enzymatic debridement, but relies on enzymes produced by the tissue itself. Autolytic debridement is enhanced by using dressings that maintain moisture (Reyzelman 2015; Konig 2005). Biological debridement involves the application of sterilized green bottle fly maggots to consume dead tissue and bacteria within the wound (Tanyuksel 2005; Pereira 2016). Although some patients and physicians may find maggot therapy distasteful, this approach has been used successfully for centuries and there is abundant evidence for the efficacy of maggots in wound debridement. Emerging research even suggests that the biologic secretions of the maggots may promote wound healing. For these reasons, maggot therapy is a treatment option for chronic, non-healing, and infected wounds, despite the possible need to overcome prejudice (Nigam 2016).
It is not uncommon for opportunistic bacteria to populate a wound site. Immune cells from circulation and the natural antibacterial properties of fluids draining from wounds usually keep these pathogens in check; however, immunosuppression can allow bacterial colonies in the wound to expand, leading to infection (Wilgus 2013; Daley 2017). Progression of infection can lead to the formation of a biofilm, in which bacteria form a coating that protects them from immune and antibiotic attack, allowing them to persist in the wound site. Biofilms are especially prevalent in chronic non-healing wounds (Percival 2015; Domenech 2013; Lebeaux 2014; Clinton 2015).
Localized indications of wound infection include: increased, foul-smelling, and cloudy or colorful drainage; increased or spreading inflammation, pain, and redness; weak tissue and wound enlargement; and spontaneous bleeding (Halim 2012; Daley 2017; Leaper 2015). Systemic signs of infection include fever, chills, and increased white blood cell count (Daley 2017; Leaper 2015).
Prevention and treatment of infection is paramount in managing traumatic wounds and surgical sites. Methods of infection control involve proper surgical set-up (Harold 2017); copious rinsing of the wound with appropriate fluids (Nicks 2010); use of topical antiseptics, antibacterial compounds, and antimicrobial silver dressings (Pereira 2016; Murphy 2012); and use of photodynamic therapy, in which a light-sensitizing compound is applied to the infection site and irradiated with visible light causing formation of free radicals that damage bacteria (Yin 2013).
Soft tissue injuries and surgical sites can be closed with staples, sutures, or specialized adhesives, alone or in combination, to limit mobility and aid in healing. For heavily contaminated traumatic injuries, closure is often delayed to allow for monitoring for infection. Any dead tissue is cleared and the wound is covered in the time before final closure (Nicks 2010).
Covering superficial wounds in an appropriate bandage can maintain a moist environment for optimal healing, reduce pain, and prevent scarring (Nicks 2010). Specialized dressings that hold in fluid yet are impermeable to microorganisms allow air movement and promote autolytic debridement. Skin substitutes and biological dressings that incorporate collagen structures and tissue-forming cells may also be used to promote healing (Murphy 2012; Dreifke 2015).
Systemic antibiotics are an important consideration for highly contaminated wounds, deep puncture wounds, and bites, as well as in patients who are immunocompromised, take steroid medications, or have prosthetic joints (Nicks 2010).
Removing pressure or tension on the wound is necessary to maintain blood flow and oxygenation in the healing tissue. This is especially important for chronic wounds. Methods for offloading include padding, orthotics, and compression hose. In addition, immobilized and bed-bound patients should be moved or turned frequently and pressure points should be carefully monitored (Klein 2014; Nicks 2010).
Parenteral and Enteral Nutrition
Parenteral (intravenous) or enteral (via tube to the digestive tract) nutrition may be needed to ensure adequate protein and nutrient intake and prevent loss of muscle mass (Genton 2011; Molnar 2014). Although parenteral nutrition was widely used in the past in burn patients, studies have shown that it is associated with a three-fold higher mortality rate than enteral nutrition. Parenteral nutrition continues to be important in critical trauma patients for whom regular eating is not possible; however, enteral nutrition is now preferred in most other cases (Clark 2017).
Additional Treatments for Chronic Wounds
Chronic wounds often require repeated rounds of debridement and greater attention to mechanical offloading and decompression strategies (Nicks 2010). Skin from other sites can be grafted onto chronic wound sites to improve blood vessel growth. Cultured skin cells from the patient or a donor may also be used to improve chronic wound healing (Dreifke 2015).