Burn Casualty Care in the Deployed Setting.

Management of wartime burn casualties can be very challenging. Burns frequently occur in the setting of other blunt and penetrating injuries. This clinical practice guideline provides a manual for burn injury assessment, resuscitation, wound care, and specific scenarios including chemical and electrical injuries in the deployed or austere setting. The clinical practice guideline also reviews considerations for the definitive care of local national patients, including pediatric patients, who are unable to be evacuated from theater. Medical providers are encouraged to contact the US Army Institute of Surgical Research (USAISR) Burn Center when caring for a burn casualty in the deployed setting.

Inhalation Injury and Toxic Industrial Chemical Exposure.

Toxic industrial chemicals include chlorine, phosgene, hydrogen sulfide, and ammonia have variable effects on the respiratory tract, and maybe seen alone or in combination, secondary to inhalation injury. Other considerations include the effects of cyanide, carbon monoxide, and fire suppressants. This Clinical Practice Guideline (CPG) will provide the reader with a brief overview of these important topics and general management strategies for each as well as for inhalation injury. Chlorine, phosgene, hydrogen sulfide, and ammonia are either of intermediate or high water solubility leading to immediate reactions with mucous membranes of the face, throat, and lungs and rapid symptoms onset after exposure. The exception to rapid symptom onset is phosgene which may take up to a day to develop severe acute respiratory distress syndrome. Management of these patients includes early airway management, lung-protective ventilator strategies, aggressive pulmonary toilet, and avoidance of volume overload.

A Survey of Temperature Management Practices Among Burn Centers in North America.

Maintaining body temperature is a unique challenge with burn care. We sought to describe core temperature goals in the operating room (OR) and the methods used to achieve and maintain these goals, along with current methods of warming in the intensive care unit (ICU), the perception of effect of increased ambient temperature on work performance, and concerns with contamination of sterile fields due to increased ambient temperature. A 24 question survey was disseminated to burn centers in the United States and Canada. The questions included demographics, target core and ambient temperatures, warming methods, and beliefs on ambient temperature's effects. Of 121 burn centers, 52 questionnaires were completed (43% response rate). The majority of centers targeted a core temperature between 36 and 38°C in the OR and an ambient temperature between 75 and 95°F in the ICU. The most common methods for maintaining core temperature included warmed ambient temperature, forced air devices, and intravenous fluids. Although the majority of centers reported the belief that increased ambient temperature benefits patients, many also reported that there is a negative impact on staff performance and risk of staff perspiration contaminating sterile fields. Burn centers reported a range of target core temperatures and methods to reach target temperatures. More than a third of respondents perceived a negative impact work performance while more than half acknowledged the potential for contamination of sterile fields. A prospective observational study is needed to determine actual temperature regulation practice patterns and its impact on outcomes.

Continuous Veno-Venous Hemofiltration During Intercontinental Aeromedical Evacuation.

Overseas contingency operations which occur in areas lacking medical infrastructure pose challenges to the stabilization and transportation of critically ill patients. In particular, metabolic derangements resulting from acute kidney injury (AKI) make long-distance aeromedical evacuation risky. Here, we report the first modern use of in-flight continuous veno-venous hemofiltration (CVVH) for intercontinental aeromedical evacuation. Hospital and transport records were reviewed for a 31-yr-old male active duty service member who sustained 40% total body surface area full thickness burns after high-voltage electrical exposure in the southern Philippines. He was evacuated to the Burns Centre at Singapore General Hospital, where CVVH was initiated for anuric AKI secondary to rhabdomyolysis. The United States Army Institute of Surgical Research (USAISR) Burn Flight Team transported the patient to the USAISR Burn Center at Fort Sam Houston, TX, USA. CVVH was performed in-flight for 15 h out of 19.5 h of total flight time. CVVH settings were maintained as follows: blood flow 250 mL/min; replacement fluid rate 3,500 mL/h; and no ultra-filtrate removal. Unfractionated heparin at 500 units/h was utilized for regional anticoagulation. No filter clotting was encountered; a planned filter change was performed during a midway refueling stop. Pre-flight hyperkalemia was managed with low-potassium replacement fluid. No fluid was removed in the setting of large wound insensible losses. The patient remained hemodynamically stable and required no vasoactive medications. Continuous veno-venous hemofiltration can be used safely during high-altitude flight to evacuate casualties with AKI from distant contingency operations. The use of portable hemodialysis equipment in this case also proves the feasibility of deploying renal replacement therapies to more forward facilities than previously considered.

Perioperative Temperature Management During Burn Care.

Major physiologic alterations following a severe thermal injury disrupt thermal homeostasis and predispose burn patients to hypothermia. An important recommendation in many clinical practice guidelines is to increase the ambient temperature during the care of severely burned patients in the operating room and intensive care unit to mitigate the loss of thermoregulation, prevent hypothermia, and minimize the impact of hypermetabolism. However, the scientific support for this recommendation remains unclear. This review summarizes the current knowledge regarding the pathophysiology and treatment of thermal injury-induced hypermetabolism and hypothermia, with special emphasis on alterations in ambient temperature. Current evidence on the value of increasing ambient temperature during the care of severely burned patients in the operating room or intensive care unit is limited, with minimal human studies investigating physiologic benefit or potential adverse effects.

Predicting the proportion of full-thickness involvement for any given burn size based on burn resuscitation volumes.

INTRODUCTION: The depth of burn has been an important factor often overlooked when estimating the total resuscitation fluid needed for early burn care. The goal of this study was to determine the degree to which full-thickness (FT) involvement affected overall 24-hour burn resuscitation volumes. METHODS: We performed a retrospective review of patients admitted to our burn intensive care unit from December 2007 to April 2013, with significant burns that required resuscitation using our computerized decision support system for burn fluid resuscitation. We defined the degree of FT involvement as FT Index (FTI; percentage of FT injury/percentage of total body surface area (TBSA) burned [%FT / %TBSA]) and compared variables on actual 24-hour fluid resuscitation volumes overall as well as for any given burn size. RESULTS: A total of 203 patients admitted to our burn center during the study period were included in the analysis. Mean age and weight were 47 ± 19 years and 87 ± 18 kg, respectively. Mean %TBSA was 41 ± 20 with a mean %FT of 18 ± 24. As %TBSA, %FT, and FTI increased, so did actual 24-hour fluid resuscitation volumes (mL/kg). However, increase in FTI did not result in increased volume indexed to burn size (mL/kg per %TBSA). This was true even when patients with inhalation injury were excluded. Further investigation revealed that as %TBSA increased, %FT increased nonlinearly (quadratic polynomial) (R = 0.994). CONCLUSION: Total burn size and FT burn size were both highly correlated with increased 24-hour fluid resuscitation volumes. However, FTI did not correlate with a corresponding increase in resuscitation volumes for any given burn size, even when patients with inhalation injury were excluded. Thus, there are insufficient data to presume that those who receive more volume at any given burn size are likely to be mostly full thickness or vice versa. This was influenced by a relatively low sample size at each 10%TBSA increment and larger burn sizes disproportionately having more FT burns. A more robust sample size may elucidate this relationship better. LEVEL OF EVIDENCE: Therapeutic/care management study, level IV.

Vitamin C in Burn Resuscitation.

The inflammatory state after burn injury is characterized by an increase in capillary permeability that results in protein and fluid leakage into the interstitial space, increasing resuscitative requirements. Although the mechanisms underlying increased capillary permeability are complex, damage from reactive oxygen species plays a major role and has been successfully attenuated with antioxidant therapy in several disease processes. However, the utility of antioxidants in burn treatment remains unclear. Vitamin C is a promising antioxidant candidate that has been examined in burn resuscitation studies and shows efficacy in reducing the fluid requirements in the acute phase after burn injury.

A Survey of Mechanical Ventilator Practices Across Burn Centers in North America.

Burn injury introduces unique clinical challenges that make it difficult to extrapolate mechanical ventilator (MV) practices designed for the management of general critical care patients to the burn population. We hypothesize that no consensus exists among North American burn centers with regard to optimal ventilator practices. The purpose of this study is to examine various MV practice patterns in the burn population and to identify potential opportunities for future research. A researcher designed, 24-item survey was sent electronically to 129 burn centers. The χ, Fisher's exact, and Cochran-Mantel-Haenszel tests were used to determine if there were significant differences in practice patterns. We analyzed 46 questionnaires for a 36% response rate. More than 95% of the burn centers reported greater than 100 annual admissions. Pressure support and volume assist control were the most common initial MV modes used with or without inhalation injury. In the setting of Berlin defined mild acute respiratory distress syndrome (ARDS), ARDSNet protocol and optimal positive end-expiratory pressure were the top ventilator choices, along with fluid restriction/diuresis as a nonventilator adjunct. For severe ARDS, airway pressure release ventilation and neuromuscular blockade were the most popular. The most frequently reported time frame for mechanical ventilation before tracheostomy was 2 weeks (25 of 45, 55%); however, all respondents reported in the affirmative that there are certain clinical situations where early tracheostomy is warranted. Wide variations in clinical practice exist among North American burn centers. No single ventilator mode or adjunct prevails in the management of burn patients regardless of pulmonary insult. Movement toward American Burn Association-supported, multicenter studies to determine best practices and guidelines for ventilator management in burn patients is prudent in light of these findings.

Diagnosis and management of inhalation injury: an updated review.

In this article we review recent advances made in the pathophysiology, diagnosis, and treatment of inhalation injury. Historically, the diagnosis of inhalation injury has relied on nonspecific clinical exam findings and bronchoscopic evidence. The development of a grading system and the use of modalities such as chest computed tomography may allow for a more nuanced evaluation of inhalation injury and enhanced ability to prognosticate. Supportive respiratory care remains essential in managing inhalation injury. Adjuncts still lacking definitive evidence of efficacy include bronchodilators, mucolytic agents, inhaled anticoagulants, nonconventional ventilator modes, prone positioning, and extracorporeal membrane oxygenation. Recent research focusing on molecular mechanisms involved in inhalation injury has increased the number of potential therapies.

Care of the Burn Casualty in the Prolonged Field Care Environment.

Burns are frequently encountered on the modern battlefield, with 5% - 20% of combat casualties expected to sustain some burn injury. Addressing immediate life-threatening conditions in accordance with the MARCH protocol (massive hemorrhage, airway, respirations, circulation, hypothermia/head injury) remains the top priority for burn casualties. Stopping the burning process, total burn surface area (TBSA) calculation, fluid resuscitation, covering the wounds, and hypothermia management are the next steps. If transport to definitive care is delayed and the prolonged field care stage is entered, the provider must be prepared to provide for the complex resuscitation and wound care needs of a critically ill burn casualty.

Combat-Related Pythium aphanidermatum Invasive Wound Infection: Case Report and Discussion of Utility of Molecular Diagnostics.

We describe a 22-year-old soldier with 19% total body surface area burns, polytrauma, and sequence- and culture-confirmed Pythium aphanidermatum wound infection. Antemortem histopathology suggested disseminated Pythium infection, including brain involvement; however, postmortem PCR revealed Cunninghamella elegans, Lichtheimia corymbifera, and Saksenaea vasiformis coinfection. The utility of molecular diagnostics in invasive fungal infections is discussed.

Experience with proctectomy to manage combat casualties sustaining catastrophic perineal blast injury complicated by invasive mucor soft-tissue infections.

Catastrophic pelviperineal injuries have become more commonplace on the modern battlefield as a result of dismounted blast mechanism and the survival benefits afforded by far-forward resuscitation and surgery. Inherent in the survival of casualties with such devastating injuries is both the risk for invasive infections and the need for complex reconstruction. We report a series of two combat casualties sustaining the constellation of catastrophic pelviperineal blast injury, anal sphincter complex destruction, complicated by invasive fungal infection managed with completion proctectomy. Our experience, although lacking numbers to qualify as high-level evidence to guide care, will assist future surgeons' care for similar patients.

Determination of efficacy of novel modified chitosan sponge dressing in a lethal arterial injury model in swine.

BACKGROUND: Chitosan is a functional biopolymer that has been widely used as a hemostat. Recently, its efficacy has been questioned due to clinical failures as a result of poor adhesiveness. The purpose of this study was to compare, in a severe groin injury model in swine, the hemostatic properties of an unmodified standard chitosan sponge with standard gauze dressing and a novel hydrophobically modified (hm) chitosan sponge. Previous studies have demonstrated that hm-chitosan provides greatly enhanced cellular adhesion and hemostatic effect via noncovalent insertion of hydrophobic pendant groups into cell membranes. METHODS: Twenty-four Yorkshire swine were randomized to receive hm-chitosan (n = 8), unmodified chitosan (n = 8), or standard Accu-Sorb gauze dressing (n = 8) for hemostatic control. A complex groin injury involving arterial puncture (4.4-mm punch) of the femoral artery was made after splenectomy. After 30 seconds of uncontrolled hemorrhage, the randomized dressing was applied and compression was held for 3 minutes. Fluid resuscitation was initiated to achieve and maintain the baseline mean arterial pressure and the wound was inspected for bleeding. Failure of hemostasis was defined as pooling of blood outside the wound. Animals were then monitored for 180 minutes and surviving animals were killed. RESULTS: Blood loss before treatment was similar between groups (p < 0.1). Compared with the hm-chitosan sponge group, which had no failures, the unmodified chitosan sponge group and the standard gauze group each had eight failures over the 180-minute observation period. For the unmodified chitosan sponge failures, six of which provided initial hemostasis, secondary rebleeding was observed 44 minutes ± 28 minutes after application. Standard gauze provided no initial hemostasis after the 3-minute compression interval. CONCLUSIONS: Hm-chitosan is superior to unmodified chitosan sponges (p < 0.001) or standard gauze for controlling bleeding from a lethal arterial injury. The hm-chitosan technology may provide an advantage over native chitosan-based dressings for control of active hemorrhage.

New hemostatic dressing (FAST Dressing) reduces blood loss and improves survival in a grade V liver injury model in noncoagulopathic swine.

BACKGROUND: We performed this study to evaluate the hemostatic efficacy of the FAST Dressing in treating a grade V liver injury in noncoagulopathic swine. METHODS: Sixteen female splenectomized, noncoagulopathic swine underwent reproducible grade V liver injuries. The animals were blindly randomized to two treatment groups: (1) FAST Dressing (n = 8) or (2) IgG placebo dressing (n = 8). After 30 seconds of uncontrolled hemorrhage, dressings and manual compression were applied at 4-minute intervals. The number of dressings used, time to hemostasis, total blood loss, mean arterial pressure, blood chemistry, and total resuscitation fluid volume were monitored for 2 hours after injury. RESULTS: The mean total blood loss was 412.5 mL (SD 201.3) for the FAST Dressing group compared with 2296.6 mL (SD 1076.0) in the placebo group (p < 0.001). All animals in the FAST Dressing group achieved hemostasis and survived for the duration of the experiment (2 hours) after injury, whereas none of the animals in the placebo group attained hemostasis or survived to 2 hours after injury (p < 0.001). The mean time to hemostasis was 6.6 minutes (SD 2.5). A median of five dressings (mean absolute deviation 1.0, p = 0.007) was sufficient to control hemorrhage in the FAST Dressing group. CONCLUSION: The FAST Dressing reduced blood loss and improved survival compared with placebo in a noncoagulopathic, grade V liver injury swine model.