Wound Management in Disaster Settings

Background Few guidelines exist for the initial management of wounds in disaster settings. As wounds sustained are often contaminated, there is a high risk of further complications from infection, both local and systemic. Healthcare workers with little to no surgical training often provide early wound care, and where resources and facilities are also often limited, and clear appropriate guidance is needed for early wound management. Methods We undertook a systematic review focusing on the nature of wounds in disaster situations, and the outcomes of wound management in recent disasters. We then presented the findings to an international consensus panel with a view to formulating a guideline for the initial management of wounds by first responders and subsequent healthcare personnel as they deploy. Results We included 62 studies in the review that described wound care challenges in a diverse range of disasters, and reported high rates of wound infection with multiple causative organisms. The panel defined a guideline in which the emphasis is on not closing wounds primarily but rather directing efforts toward cleaning, debridement, and dressing wounds in preparation for delayed primary closure, or further exploration and management by skilled surgeons. Conclusion Good wound care in disaster settings, as outlined in this article, can be achieved with relatively simple measures, and have important mortality and morbidity benefits.


Introduction
In naturally occurring and man-made disaster situations, wounds are a major source of morbidity and mortality. They place substantial demands on strained, disrupted, and often rudimentary and makeshift health services. Wounds tend to be contaminated by a variety of environmental organisms and foreign matter, with crushed and devitalized tissue providing a medium for bacterial growth and invasion. First responders are often not medically trained and, though well intentioned, the treatment they provide is often compromised by a misconception that wounds should be closed to enable them to heal [1]. Experienced surgeons know that poor early wound management is often complicated by more extensive infection and tissue necrosis requiring wide excision or amputation, and preventable systemic sepsis, gangrene, and mortality [2]. Safe and effective early management of wounds by first responders in a disaster setting can prevent complications and save limbs and lives, and both first responders and subsequent healthcare personnel should be clear about what this entails.
Disasters such as the 2004 Tsunami, Hurricane Katrina in 2005, and the 2010 Haiti earthquake, were all characterized, to greater or lesser degree, by remote location, overwhelming numbers of casualties, inadequate resources, over-burdened healthcare services, and inexperienced caregivers. Much has been written about the health consequences of these disasters in general. We aimed to systematically review the nature of wounds and outcomes of wound management in recent disasters, and we then convened an international consensus panel to consider these results and formulate a concise guideline for the initial wound management for first responders and non-expert healthcare providers. It was anticipated that a generic guideline could be widely distributed, discussed among members of relevant organisations, modified according to local needs where required, and put into practice in many types of clinical settings.

Methods
We searched Cochrane Library (Wiley), Cinahl (Ebscohost), Medline (Ovid), Embase (Elsevier), and WHO Guidelines with the key words ''wounds,'' ''crush injuries,'' ''open fractures,'' with related complications such as ''infections,'' ''necrosis,'' ''tetanus.'' These terms were combined with disaster-related key words such as ''tsunami,'' ''cyclone,'' ''earthquake,'' and ''flood.'' The search included articles published up to 1 September 2012. The searches were limited to English language publications and human studies. The present review excluded burns, military blast injury, high-velocity injury, and penetrating injury. The reference lists of included articles were searched for other potentially relevant publications. Each article was assessed independently by two reviewers.
We then collated results and presented them to a consensus meeting of experts in surgery and disaster medicine  (Table 1). This group considered the review findings and discussed and sought agreement on a set of principles that were then presented for comment and critique to an International Symposium on the Global Burden of Surgical Disease involving 151 delegates. The present report presents the results of these deliberations and a proposed simple guideline.

Results
Our literature search yielded 2,894 articles for screening, from which 62 proved to be relevant, as shown in Fig. 1 The nature of wounds Depending on the nature of the catastrophe, extreme forces led to a spectrum of wounds variously characterized by multiple breaches of skin, deep puncture injuries [3], crushing and destruction of soft tissues, fractures of bone, and contamination with dirt, mud, seawater, sand, and debris, as well as feces and saliva [1,[4][5][6][7][8].
Of course many victims also had life-threatening respiratory or circulatory impairment or significant head and internal injuries. In earthquake-related disasters, 30 % of patients had head and neck injuries, and a quarter had significant chest, thoracolumbar spine, or spinal cord injuries, a third of whom required surgical interventions [9]. Musculoskeletal injuries are common, in earthquakes in particular, with the proportion of patients with closed fractures, sprains, open fractures, and neurovascular injury observed to be approximately 22, 6, 11-54, and 6 %, respectively [9].

Infection
High rates of infection occurred from contamination, tissue loss, inadequate or delayed wound cleaning and debridement, and premature wound closure [1,6,8]. For example, delayed initial wound care more than 24 h after injury and primary wound closure were independent predictors of secondary wound infection among tsunami victims [6]. Environmental pathogens and contaminated water used for cleaning wounds were the usual causes. Infections were often polymicrobial and included atypical bacteria and fungi [1,7,9], as detailed in Table 2.
Among wounded tsunami survivors, it was estimated that half to two-thirds of wounds became infected, mostly within the first 72 h following the event [6], although many wounds were infected within the first 24 h [10]. Aeromonas   was the single most common pathogen identified among tsunami survivors, accounting for over 20 % of infections [14]. Other, mostly Gram-negative bacteria [6] were also common, particularly E. coli and Klebsiella pneumoniae, as well as S. aureus, Proteus vulgaris, and P. aeruginosa [6]. Sepsis with or without necrotizing fasciitis was frequently seen following flood and tsunami wounds [10,15], and it was associated with more than doubling of mortality (OR 2.45, 95 % confidence interval [CI] 1.52-3.96) [11].

Crush syndrome
Nine review articles and three descriptive studies each addressed crush syndrome, which is acute renal failure secondary to hypovolemia and rhabdomyolysis from muscle damaged at any of three different times: the time of   the initial mechanical crushing force, during periods of ischemia, and during reperfusion [9,[16][17][18]. While skeletal muscle was thought to be relatively tolerant of ischemia for 2-4 h without permanent injury, it is likely that irreversible changes that limit functional recovery start to occur in as little as 1 h [18], especially when there is concurrent tissue damage and other injuries. Death often ensues due to hypovolemia and hyperkalemia [9]. Among earthquake survivors [3], the reported incidence of crush syndrome was 2-15 % [3,9]. Entrapped time under the debris, multiple crush injuries, male gender, presence of infection, and creatinine kinase (CK) level were all predictive of acute renal failure [19]. Survival depended on limiting the degree of renal dysfunction and supporting organ function, and mortality was reported to be up to 48 % [9,17,20].

Management
The panel agreed on the principles of basic wound care in disasters, which are presented in Table 3. These highlight the importance of meticulous wound care even when resources and expertise are limited, recognizing that poorly managed wounds are associated with high mortality from sepsis and crush syndrome.

Initial patient management
Protocols for field-based triage and initial assessment of injured patients should prioritize identification and management of life-threatening conditions [21]. Early maneuvers to secure the airway, ensure adequate ventilation, and stop bleeding must take precedence over assessment and management of a non-bleeding extremity wound. Of course, wounds may compromise the airway, ventilation, cardiac function, or cause substantial hemorrhage, of which the latter may need to be addressed through application of direct pressure or a temporary tourniquet.

Basic wound assessment and management
Injuries to extremities should be addressed after initial assessment for life-threatening injuries and resuscitation has taken place [21]. Wounds must be carefully inspected, and assessment must be made for associated injuries, distal function, bone and soft tissue injury, and underlying neurovascular injury. In major earthquakes these types of injury occur in approximately 1 in 20 patients sustaining limb injury [9]. Assessment of the degree of contamination, devitalized tissue, presence of foreign bodies, and integrity of underlying structures may require wound extension and formal exploration, under anesthesia if it is available.
After adequate assessment, aggressive cleaning and debridement are required [6,22]. Foreign bodies should be removed, and obvious embedded ones should be scrubbed before exploration, wound debridement, and removal [22] if possible. Devitalized tissue needs appropriate debridement by trimming or excising around the wound edge [22]. In one study of contaminated wounds, debridement was associated with reduced wound infection rates from 62.5 to 2 % [23].
Irrigation can be done with isotonic saline, distilled water, boiled and cooled water, dilute antiseptic solution, sterile water, or drinkable/potable tap water, with similar efficacy [24]. Untreated river water and seawater have high levels of contaminants and should not be used [25]. Dilute antiseptics, such as 1 % povidone-iodine or a 5 % solution of sodium benzyl penicillin have been shown to decrease infection rates and can be used in addition to water or normal saline [26][27][28].
Value of delayed primary closure All primary and review articles confirmed that wounds sustained in disaster events are contaminated, especially when presentation is delayed, and that early primary wound closure causes high rates of serious wound infection eventually requiring much more extensive debridement and sometimes leading to the death of the patient [4,6,15,29]. Such wounds should therefore be closed in a delayed fashion, which is associated with much lower infection rates. The only exception, for which initial wound closure has provided acceptably low rates of subsequent wound infection, is when primary closure followed wound assessment, meticulous debridement of all foreign material and devitalized tissue by an experienced surgeon within 6 h of injury [30].
Delayed primary closure consists of initial adequate debridement followed by wound dressing, careful wound reassessment at 48 h, repeat debridement and dressing if necessary, and, finally, closure 48 h or longer after initial inspection, but only if the wound is clean and free of foreign material and contaminated and devitalized tissue [31]. Simple closure techniques using strips, sutures, or staples can be employed if the wound edges can be brought together without undue tension. Delayed primary suturing gives similar cosmetic outcomes to immediate suture, even when closure is achieved 2-5 days after wounding. Wounds that cannot be closed without tension will need to be left open to heal by secondary intention or closed by skin graft or flap as appropriate.

Dressings
A clean, dry, absorbent dressing is usually sufficient to minimize ongoing contamination. Our search identified three systematic reviews [27,32,33], two randomized controlled trials [34,35], and two other review articles [15,36] that sought to determine whether any particular type of dressing was associated with superior outcomes compared to another.
It appears that an absorbent gauze dressing or salinesoaked gauze dressing and coverage with dry gauze are sufficient [15,22,34,37]. Occlusive dressings have not been shown to further reduce infection, hasten healing, or be associated with less pain [34]. There is little evidence to support superior results over simple gauze dressings from the use of antibiotic or silver impregnated dressings and gels [33,36,38,39], or antibiotic beads [40]. Medical-grade honey is reported to have peroxide and antibacterial activity, but little evidence of better outcomes exists to support its use [41,42]. In patients with properly debrided wounds, there is also little evidence of reduction in mortality or severe infection with the additional use of advanced technologies, such as negative pressure wound therapies or hyperbaric oxygen, which may mitigate anaerobic infection by promoting a hyperoxic wound environment [9,43]. There is some evidence that, where available, negative pressure wound therapies, which likely reduce tissue edema [44], allow earlier delayed primary closure [32,35,45]. However, such advanced technologies are unlikely to be available early on in the setting of a disaster when wounds are fresh.

Systemic antibiotics
While topical antibiotics have not been shown to significantly influence wound infection rates [38], systemic antibiotics play an adjunct role to proper initial wound care and delayed primary closure [21,46]. Their availability at the time of initial wound care is the main limitation for prophylaxis. Various prophylactic regimens have been recommended, ranging from a single dose of beta-lactam penicillin in patients with mildly contaminated wounds [22] or in operations for the treatment of closed fracture [47], to longer durations in wounds affecting the hands [21] and feet, as well as in all open fractures [25]. Antibiotic use has had protective effects against early infection in open fractures of the limb [46]. In established infections, antibiotics are an essential component of wound care.

Tetanus prophylaxis
Tetanus prophylaxis or mass vaccination campaigns have been rolled out in disaster settings [9,21], and have shown that unnecessary vaccination is unlikely to cause harm [51]. Tetanus-prone wounds are those that are stellate in shape or longer than 1 cm, more than 6 h old, that contain devitalized tissue or gangrene, or are contaminated with dirt, saliva, or feces [5]. Avulsion injuries are also prone to tetanus. Proper initial wound care and debridement are critical for tetanus prevention [51].
The need for post-exposure prophylaxis for tetanus depends on each patient's previous immunization status. When immunization status is unknown, or if the patient has received fewer than three previous doses of tetanus toxoid, both tetanus toxoid and tetanus immunoglobulin should be administered. A second dose of toxoid should be given within the next 2 months, followed by a third dose in the following 6-12 months [5,50,51]. In cases of completed immunization within 5 years, it appears unnecessary to give either tetanus toxoid or immunoglobulin. If completed immunization was longer than 5 years before injury, patients should be given a single dose of tetanus toxoid [5,50,51]. Pediatric patients (under 7 years of age), can be given the diphtheria, pertussis, tetanus (DPT) vaccine instead of tetanus toxoid [5,51].

Documentation
Although none of the articles reviewed made specific reference to the need for appropriate documentation, the panel regarded clear, concise documentation of wound management to be crucial to monitoring and follow-up of each wound.
Details to be recorded include (1) the mechanism of injury (e.g., penetrating, laceration, abrasion, blast); (2) a description of the wound, including the location of the injury on the body; (3) the wound size, depth, margins, and base, and any neurovascular structures involved; and (4) any management that has been undertaken and any further action required, making clear the date and time of planned wound review.

Entrapment and extrication
The entrapped victim presents the concurrent challenges of time-critical life-saving interventions and freeing the victim, followed by prevention and minimization of the harmful systemic effects of crush injury and the management of wounds and other injuries. Primary management of World J Surg (2015) 39:842-853 849 the entrapped victim consists of early fluid administration and coordinated extrication; however, if an entrapped limb is preventing early extrication, then amputation at the scene may be a life-saving measure [18,44]. While limb amputation before release of the crushing force may prevent the sequelae of the reperfusion syndrome and minimize the systemic insult, it is also associated with substantial morbidity and should be done only if other options for preserving crushed limbs have been exhausted [18]. Surgical expertise is often required to remove and safely extricate an injured survivor from the scene of a disaster [9,16,21,44,52], and medical expertise is often needed immediately afterwards to manage the complications of prolonged entrapment and reperfusion injury.

Crush injury, compartment syndrome, and avoidance of fasciotomy
Crushing of a limb often leads to swelling, painful tense compartments, altered sensation, and sometimes absent distal pulses. In civilian settings a limb with these signs would usually be treated with resuscitation, limb immobilization, fracture fixation, and fasciotomy to reduce compartment pressures and restore capillary circulation.
In disaster settings, it is unclear whether the benefits of fasciotomy outweigh the risks associated with further wounds, which may act as a portal for infection of underlying devitalized muscle. In one study of earthquake victims, 81 % of fasciotomies became infected, and fasciotomy was therefore a significant factor in sepsis (p \ 0.001) and mortality (p \ 0.0001 [9]).
A reasonable strategy that balances potential benefits and harms in limbs with viable musculature, as indicated by responsiveness to mechanical or electrical stimulation, is for fasciotomy to be performed only if intra-compartment pressures are greater than 40 mmHg [17] or distal pulses are absent [18,44]. Salvage of muscle is likely to be futile in limbs that have been crushed for a prolonged period and show evidence of devitalized muscle by lack of responsiveness to stimulation. In this situation, debridement of devitalized tissue should be the priority.
Systemic effects of crush injury, especially rhabdomyolysis, should be expected [19]. A urine dipstick to detect myoglobin and subclinical rhabdomyolysis can be useful in the field to triage patients; however, the serum CK level is a more sensitive biochemical marker once pathology services are available [9]. A serum CK level greater than 5,000 U/L has been shown to be the best predictor of acute renal failure in crush-injured patients, with mortality in the range of 14-48 % [9]. Urgent treatment and critical care monitoring are almost always needed if the serum CK level reaches 20,000 U/L [16]. Electrolyte abnormalities are common, and hyperkalemia and hypovolemia can be fatal, so serum potassium levels, CK level, cardiac status, and arterial pH should be measured three to fours times daily in the first few days [9,17,18].
Early intravenous fluid administration prior to extrication can help prevent acute renal failure due to rhabdomyolysis [9,17,20]. Treatment of crush syndrome usually requires early aggressive hydration and forced diuresis (urine output of 100-200 mL/h), alkalinization of urine (pH 6.5 or more), and maintenance of arterial pH \7.5 [16,20,53]. Hemodialysis, if available, will often be initiated if the serum creatinine is greater than 1.5 mg/dL [16,53].

Fractures
Basic principles of fracture management should be followed, which include temporary splinting to minimize pain and bleeding and prevent further soft tissue or neurovascular injury during transportation to more specialized services [53]. Patients with open fractures should receive early systemic antibiotic treatment and tetanus vaccination [53]. External fixation is often a mainstay of early management Maximum limb preservation must be considered of the mangled limb, allowing wounds and soft tissues to be properly assessed and managed even when definitive fracture fixation is unavailable [54]. Early referral should be planned to a facility capable of managing fractures and other needs of the victims.

Delayed amputation
Other than as a life-saving procedure to extricate a trapped person where other options have been exhausted, amputation of a mangled or devitalized limb should only be performed by a suitably qualified person after careful evaluation of the limb and the patient [9,16,21,44,52]. Aids to assessment, such as the Mangled Extremity Severity Score (MESS), have been developed to guide decision making [52]. The main indications for amputation have been irreparable vascular injury, completion of partial amputation and, as a last resort in patients with severe soft tissue damage, with or without fractures and deteriorating renal and cardio-respiratory function, as well as overwhelming sepsis [21].
Wounds of the head, neck, face, hands, and feet In disaster settings wounds on the face, neck, hands, and feet should be managed according to the same principles, as they have early wound infection rates exceeding 50 % [2,4,37,54,56].
Although it may be technically challenging to treat injuries to these sites, adequate debridement and delayed primary closure are still key to preventing severe wound infection. In one series the infection rates among patients who had and had not undergone wound debridement were 2 and 62.5 %, respectively [23]. Where there are cosmetically challenging wounds, early referral to an experienced surgeon may reduce the risk of eventual disfigurement or loss of function. In any wounds of the head, neck, or face early consideration needs to be given to the possibility of brain or airway injury.

Discussion
Through this systematic review we provide an evidencebased overview of the clinical challenges of managing wounds among survivors of natural and man-made disasters. We also provide evidence of suboptimal wound management in recent disasters, noting that these wounds could have been better managed with adherence to some key principles. The review and the deliberations of the international panel have clarified and redefined these key principles, distilled from a variety of sources, that together comprise the necessary aspects of good wound care in austere environments. It is anticipated that adherence to these practices will minimize preventable deaths and improve the outcomes and quality of life among survivors.
The most critical step is avoiding premature closure of contaminated and inadequately cleaned and debrided wounds. Simple cleaning, dressing, and review of wounds at 48 h allows identification and adequate management of the vast majority of wound infections that could otherwise be life-threatening or limb-threatening. When the open wound is re-inspected, the presence of erythema, purulent exudate, necrotic core, and tissue edema are all signs that the wound should not yet be closed, that further cleaning and debridement should performed, and that antibiotic therapy should be considered. The wound should then be redressed and inspected another 48 h later.
The review and deliberations also highlighted the challenges faced in standardizing these practices. In disaster settings health care services are usually overburdened, first responders are often inexperienced in wound care, and resources are mostly inadequate. Experienced surgeons who can manage complex wounds are usually a scarce resource, and crucial strategies, such as delaying wound closure, may be unfamiliar to those immediately responsible for care of the victims.
The consensus panel acknowledged that promoting practice improvements among dispersed, relatively unskilled personnel working at unpredictable times in austere environments with few of the usual clinical resources is a very challenging task. We regarded a wide dissemination strategy and endorsement by relevant clinicians and their representative organizations to be essential. With this in mind, our panel developed a simple generic poster that provides guidelines for wound care in disaster settings (Fig. 1). It is anticipated that the poster would be useful for promoting discussion about optimal wound management, for education, and for field-based guidance in the acute aftermath of a disaster. It is presented as a simple A, B, C, D, E, F, G aide de memoir for easy reference and to facilitate recollection. This poster can be modified for local use if necessary, and included in disaster management equipment packs, and in emergency care facilities during disaster situations. It was launched at the joint meeting of the RACS International Committee and the Alliance for Surgery and Anesthesia Presence at the Royal Australasian College of Surgeons and Australian and New Zealand College of Anaesthetists Annual Scientific Congress in Singapore on 5 May 2014, and it is likely to be made available for download from many surgical college websites. development and dissemination of the Wound Care in Disaster Settings guidelines has been supported by the Royal Australasian College of Surgeons through its International Committee.