Whenever presented with a patient that has sustained trauma, whether it be from a bite wound, a road traffic accident, or a burn wound, there are certain steps that should be taken in order to stabilise the patient. There will be some variation, depending on the injury sustained, but wound management is one component of the overall assessment of the patient.
When dealing with the classic traumatic wound, a careful and detailed assessment of the patient should be performed before wound management commences. That said, at the same time, consideration of the wound needs to be made, in order to reduce haemorrhage, prevent further contamination by the patient and the environment, and to prevent dessication of the wound. In these initial stages some type of protective dressing or bandage should be applied. Depending on the location of the wound this may require some extensive bandaging, e.g. penetrating wounds to the thorax or abdomen (Figure 1), or a simple pressure dressing, e.g. cut pad.
At this early stage, consideration should be made as to the degree of contamination with bacteria, or infection, and so it is useful to take a swab for microbiological culture and sensitivity. This swab is collected into appropriate transport media, e.g. charcoal swab, and can be either sent off for analysis immediately, or retained, at either room temperature or refrigerated, for later laboratory testing.
Post-trauma patient assessment
Immediate consideration of the patient's major body systems should be performed; this involves assessment of the ABC's — airway, breathing and circulation. These parameters should be examined in all emergency patients as part of the triage process, but trauma patients are likely to have very obvious injuries, e.g. wounds, fractures, prolapsed organs (Figure 2), which are obvious but not immediately life threatening, and can distract the clinician from more serious, life-threatening injuries, e.g. haemoabdomen, pneumothorax. Patients with haemorrhagic wounds should have a pressure dressing applied early in the treatment process, in order to prevent further blood loss and worsening hypovolaemic shock. Once the patient is deemed more stable, a more thorough physical examination should be performed, first of all to assess all major organ systems, and then to assess the wound(s). Analgesia is an essential part of the treatment plan for these patients; appropriate analgesia should be administered to any patient which is thought to be painful. It is useful to perform a brief neurological examination of the patient before the administration of analgesics such as opioids, in order to determine any deficits, and assess patient mentation. There is often concern regarding the side effects of opioids, such as respiratory depression, therefore close and regular monitoring should be performed, and incremental doses of drugs, such as opioids administered, thereby minimising any potential side effects. Opioids produce depression of ventilation, caused by a depressant effect on the brainstem respiratory centre, i.e. a reduced response to hypercapnia and hypoxaemia, and this effect is dose dependent (Yamaoka and Auckburally, 2013).
If there is a suspicion of fractures, or joint instability, then it may be necessary to apply some form of temporary stabiisation, e.g. Robert Jones type support dressing, or a splint.
Initial dressings in these patients, until stabilisation is achieved, will often be very simple, e.g. sterile water-soluble gel or hydrogel, with a dressing to maintain a moist wound environment, e.g. foam dressing, with light bandage layers used to hold this dressing in place (Krahwinkel and Boothe, 2006). As mentioned, it is useful to perform microbial sampling (bacteriology swab) before empirical antibiotic therapy is commenced (Dernell, 2006). The use of the topical dressing prevents bandaging materials from adhering to tissues, and decreases further contamination, while the use of water-soluble gels, will help facilitate wound cleansing later in the wound management process.
Initial wound assessment
Once any life-threatening injuries have been assessed, and stabilisation has been performed, or is ongoing, a thorough examination of the wound should be performed. Ideally the aetiology of the wound should be considered, as this will help give the clinician some understanding as to the level of contamination, amount of likely necrotic tissue, and whether ischaemia is likely to occur. Wounds created by different types of insults will have varying levels of tissue damage, contamination, treatment approaches, and prognoses (Swaim and Henderson, 1997; White, 1999). In some situations, this will help give information on factors such as post-operative dehiscence, and the extent of tissue damage can also be assessed at the same time, along with a visual inspection; however, thorough exploration of wounds should be performed under anaesthesia once the patient is deemed stable enough. The classic example being that of bite wound patients, whereby the external crushing injuries and puncture wounds can be detected on initial assessment, but because of the deeper tissue damage and vascular compromise, the wound is likely to worsen over the following 12 to 24 hours to involve extensive tissue loss (Figure 3 and 4). These types of wounds can initially look quite superficial, but will be associated with vascular damage, due to tearing of the dermis from the subcutaneous pleux, with the most significant damage being below the surface (Pavletic and Trout, 2006). When dealing with these types of wounds, initial wound cleaning, lavage, minor debridement and open wound management may be preferred over aggressive wound treatment, in order to better establish the extent of the tissue damage, i.e. use a staged debridement technique. Aggressive immediate treatment of these cases may result in the removal of tissue which may be viable, but was in a state of vascular stasis (Dernell, 2006).
The extent of tissue damage can usually be assessed effectively within 24 hours following injury (White, 1999). In general, the risk associated with delaying aggressive wound management following the traumatic incident rarely exceeds the risk of acting too quickly, and thereby resulting in inadequate or excessive treatment. During the waiting period, appropriate analgesia and antibiosis should be given, and topical treatment should be performed (Swaim and Henderson, 1997; Williams, 2009). The use of systemic antibiotics is commonly warranted if the muscles and fascia have been injured, if the patient is deemed to be severely immunocompromised, or if signs of local, or systemic, infection are present. The most common bacterial organisms encountered in surface wounds are coagulasepositive staphylococci and Escherichia coli (Williams, 2009, Swaim and Henderson, 1997).
Adequate clipping of the wound should be performed as part of wound preparation, as well as for decreasing potential further contamination; this procedure will also allow wound inspection. Prior to clipping, the wound should be filled, or packed, with sterile water-soluble gel, or sterile swabs, or a combination of both. The hair around the periphery of the wound should be removed using sterile scissors, which have been dipped into sterile gel in order to trap the hair and prevent it falling into the wound (Swaim and-Henderson, 1997). The initial wound cleansing lavage may occasionally be performed in a conscious patient, but often, in severely traumatised or painful patients, chemical restraint or general anaesthesia will be required in order to perform effective wound cleansing.
In cases of severe contamination, initial wound lavage can be performed using warm tap water, e.g. using a showerhead on a sink table. The advantage to using this technique is that large volumes of water can easily, and cheaply be used (Buffa et al, 1997; Dulecki and Pieper, 2005; Aldridge, 2013a, b) and allows the removal of debris. In studies tap water has been shown to be cytotoxic to fibroblasts, but in cases where the benefits from removal of debris and initial bacterial contamination outweigh the risk of tissue damage, it is considered an appropriate technique (Williams, 2009; Aldridge, 2013a, b).
If there is minimal to moderate contamination, initial wound cleaning should be performed using isotonic crystalloids (lactated Ringers solution or 0.9% sodium chloride) or a dilute chlorhexidine solution, i.e. 0.05% chlorhexidine solution or 1% povidone iodine solution (Dernell, 2006). The chlorhexidine solution can be used safely in any situation, and the povidone iodine aids in decreasing bacterial contamination, without causing significant damage to exposed tissues (Dernell, 2006). Lavage pressures of of 8–12 psi should be use, this amount of pressure is required to effectively remove debris and to overcome the adhesive forces of bacteria, pressures higher than 15 psi, can result in debris and bacteria being driven deeper into tissues, rather than facilitating their removal (Williams, 2009; Aldridge, 2013a, b). The most common techniques used to achieve these pressures include fitting a 18 gauge needle to a 20 ml syringe, or adding an 18 gauge needle to a fluid administration set and placing the fluid bag inside a pressure infuser bag, which is inflated to apply a pressure of 400 mmHg (Dulecki and Pieper, 2005).
Diagnostic wound evaluation
As mentioned, a thorough assessment is vital for all wounds. Anaesthesia, or sedation, it likely to be required in order to do this effectively as the wound will need to be aggressively explored in order to assess the extent of the injury, and damage to any underlying structures or organs. This exploration needs to be performed carefully, in order to prevent accidental contamination of deeper tissues or body cavities, particularly when exploring wounds over the thorax or abdomen (Shahar et al, 1997). Exploration should be carried out using sterile instruments and aseptic technique irrespective of the level of contamination within the wound. Observation should be made for any orthopaedic injuries, and radiographs and other imaging performed, if there is suspicion of a fracture. If a fracture is detected, then temporary stablisation must be performed before continuing with wound management. If the fracture is found to be open (careful assessment of the overlying skin should be performed to assess for any defects where the fracture may have penetrated the skin as this can often be missed when fractures are not obviously open) it is important not to push the penetrating fracture back beneath the skin. The fracture should be splinted in its current position. Reduction of such an open fracture then needs to be delayed until sterile operative conditions can be achieved in order to minimise deep tissue contamination from the skin penetration. If there is evidence of an open joint (commonly encountered with shearing injuries) immediate treatment should be performed (Beardsley and Schrader, 1995). Following cleaning and extensive lavage, closure of any remaining joint capsule should be attempted, along with ligament structures, to help stabilise the joint. After wound debridement and joint closure, external stabilisation should be used (as part of the bandage support) to decrease continued damage to capsular and intra-articular tissues (Figures 5 and 6).
If tendons, ligaments, or nerves are found to be damaged, aggressive debridement of the wound and these structures should be performed as soon as possible. Delaying this procedure will result in tissue contraction, making a subsequent repair difficult or impossible (Dernell, 2006). If severe trauma to the surrounding tissues exists, primary anastomosis of tendons, ligaments, and nerves can be performed to combat contraction while the surrounding tissues undergo staged debridement. Delayed secondary anastomosis can then be performed once the surrounding tissues are healthy (Berg and Egger, 1986; Swiontkowski, 2002; Slutsky, 2005). In most cases, repair of severed vessels need not be performed, since the collateral circulation will be sufficient to maintain tissue viability; it is possible to repair large vessels however (Kerstetter and Sackman, 1998).
If there is concern regarding significant contamination of the wound, or there are obvious signs of established infection, e.g. redness, swelling, purulent exudate, offensive smell, pyrexia, then antimicrobial therapy should immediately be commenced. This can be guided by performing Gram staining of the wound in order to establish the predominant bacteria present (Swaim and Henderson, 1997). Culture samples can be obtained, as previously mentioned, during the initial wound exploration, or during the debridement process. Obtaining the samples while performing debridement gives the advantage of taking the samples from deeper tissues, following the removal of more superficial (severely contaminated) tissues, thereby resulting in a sample which is more representative of the level of infection, and the bacterial species involved, and this technique is superior to taking surface swabs (Dernell, 2006). If antimicrobial solutions are to be used to flush the wound at any stage, then the bacteriology samples need to be obtained before these solutions are used. Tissue samples taken should be submitted for laboratory testing using a culture transport medium. Once the results of such testing are obtained, the systemic antimicrobial therapy can be continued, or changed, based on the microbial species that are found.
Wound closure considerations
Following exploration and wound cleaning the decision needs to be made regarding closure of the wound. There are a number of factors which will affect the timing of wound closure including: the extent of tissue damage; degree of contamination; amount of local or distant tissues viable for wound closure; extent of wound contraction and epithelialisation expected (Dernell, 2006). Once the wound has been assessed and lavaged, decisions need to be made as to if, how, and when, the wound will be closed. If contamination, the potential for deep tissue injury, tissue viability or vascular compromise, is a possibility, then wound closure should be delayed, and continued debridement, and open wound management performed. Patients with wounds that are heavily contaminated, or that have extensive tissue damage, are at high risk of dehiscence unless adequate and appropriate initial wound care is performed (Figure 7). Clean wounds that are treated within 24 hours of the initial injury, e.g. incisional injuries, can frequently be managed via wound lavage, gentle debridement and primary closure, other types of wounds require careful consideration of factors present within the wound, i.e. contamination, debris, necrotic tissue, damage to underlying tissue and structure, before deciding on an appropriate treatment plan.
Options for wound closure include wound debridement, repeated lavage, and the application of dressings, which is performed in order to allow the wound to reach a point whereby it is suitable for closure. Alternatively, delayed wound closure options include delayed primary closure, secondary closure or secondary intention healing. The latter two options are performed once a healthy granulation bed has been established. If delayed closure is carried out, then the use of surgical drains needs to be considered in order to decrease the incidence of wound dehiscence.
Conclusion
Irrespective of the nature of the wound, the initial process of wound management will follow a very similar, predictable route. Successful wound management, and subsequent wound healing, very much depend on adherence to the basic principles of wound assessment, adequate care, and reassessment. Initial patient assessment, and stabilisation are vital ahead of wound assessment and decisions in the wound management process. Wound management frequently involves lavage, and exploration of the wound in order to determine the extent of underlying injury, and to plan for the possibility of primary, or delayed wound closure, following a period of open wound management. Open wound management will often comprise debridement, repeated lavage, along with the application of dressings, and reassessment in order to reach a point where the wound is suitable for closure, or where the application of wound dressings are continued, to allow the wound to heal via secondary intention.
Key Points
Conflict of interest: none.