The Effects of Rapid Rewarming on Tissue Salvage in Severe Frostbite Injury.

Frostbite is a high morbidity injury caused by soft tissue freezing, which can lead to digit necrosis requiring amputation. Rapid rewarming is a first-line treatment method that involves placing affected digits into a warm water bath. This study aims to assess the clinical practices for frostbite at facilities outside of dedicated burn centers, and any impact these practices have on tissue salvage. Retrospective chart review at a single burn center identified frostbite patients admitted directly or as transfers over a 7-year period. Records were reviewed to identify initial treatment strategies. If given, time to thrombolytics from admit was noted. Tissue salvage rates were calculated from radiologically derived tissue at-risk scores and final amputation scores. One-hundred patients were transferred from outside facilities, and 108 were direct admissions (N = 208). There was no significant difference in group demographics. Rapid rewarming was the initial treatment modality more commonly in direct admit patients (P = .016). The use of rapid rewarming did not correlate with tissue salvage (P = .112). Early use of thrombolytics had a positive impact on tissue salvage (P = .003). Thrombolytics were given 1.2 hours earlier in direct admit patients (P = .029), however there was no difference in tissue salvage rates between the groups (P = .127). Efforts should focus on larger scale study to further assess the effectiveness of rapid rewarming. Although rapid rewarming did not significantly impact tissue salvage in this study, we continue to recommend its use over less studied treatment methods, and continue to view it as an important bridge to burn center transfer and administration of thrombolytic therapy.

An Institutional Protocol for the Treatment of Severe Frostbite Injury-A 6-Year Retrospective Analysis.

The treatment of severe frostbite injury has undergone rapid development in the past 30 years with many different diagnostic and treatment options now available. However, there is currently no consensus on the best method for management of this disease process. At our institution, we have designed a protocol for severe frostbite injury that includes diagnosis, medical treatment, wound cares, therapy, and surgery. This study assess the efficacy of our treatment since its implementation six years ago. During this time, all patients with severe frostbite injury were included in prospective observational trial of the protocol. We found that this protocol results in significant tissue salvage with over 80.7% of previously ischemic tissue becoming viable and not requiring amputation. We also were able to improve our center's efficiency over the course of six years and now our current average time from rapid rewarming to delivery of thrombolytics is under six hours.

Severe Hypothermia and Frostbite Requiring ECMO and Four Limb Amputations.

Severe hypothermia and frostbite can result in significant morbidity and mortality. We present a case of a patient with severe hypothermia and frostbite due to cold exposure after a snowmobile crash. He presented in cardiac arrest with a core temperature of 19°C requiring prolonged cardiopulmonary resuscitation, active internal rewarming, venoarterial extracorporeal membrane oxygenation, and subsequently amputations of all four extremities. Although severe hypothermia and frostbite can be a fatal condition, the quick action of Emergency Medical Services, emergency physicians, trauma surgeons, cardiothoracic surgeons, intensivists, and the burn team contributed to a successful recovery for this patient including a good neurological outcome. This case highlights the importance of a strong interdisciplinary team in treating this condition.

Guidelines for Thrombolytic Therapy for Frostbite.

The data are insufficient to support standardized treatment of all patients with frostbite with thrombolytic therapy. The following guidelines, however, should be applied to all patients with cyanosis persisting proximal to the distal phalanx (Grade 3 or 4 frostbite injury) and demonstrated loss of perfusion at or proximal to the middle phalanx immediately after rewarming.

Microangiography: An Alternative Tool for Assessing Severe Frostbite Injury.

Assessment of frostbite injury typically relies on computed tomography, angiography, or nuclear medicine studies to detect perfusion deficits prior to thrombolytic therapy. The aim of this study was to evaluate the potential of a novel imaging method, microangiography, in the assessment of severe frostbite injury. Patients with severe frostbite were included if they received a post-thrombolytic Technetium 99 (Tc99) bone scan, a Tc99 bone scan without thrombolytic therapy, and/or post-thrombolytic microangiography (MA) study. We included all patients from the years 2006 to 2018 with severe frostbite injury who had received appropriate imaging for diagnosis: Tc99 scan alone (N = 82), microangiography alone (N = 22), and both Tc99 and microangiography (N = 26). The majority of patients received thrombolytic therapy (76.2%), and the average time to thrombolytics was 6.9 hours. Tc99 scans showed strong correlation with amputation level (r = .836, P < .001), and microangiography showed a slightly stronger positive correlation with amputation level (r = .870, P < .001). In the subset who received both Tc99 scan and microangiography (N = 26), we observed significant differences in the mean scores of perfusion deficit (z = 3.20, P < .001). In this subset, a moderate correlation was found between level of perfusion deficit on Tc99 bone scan and amputation level (r = .525, P = .006). A very strong positive correlation was found between the microangiography studies and the amputation level (r = .890, P < .001). These results demonstrate that microangiography is a reliable alternative method of assessing severe frostbite injury and predicting amputation level.

Emergency Care of Pediatric Burns.

Although the overall incidence of and mortality rate associated with burn injury have decreased in recent decades, burns remain a significant source of morbidity and mortality in children. Children with major burns require emergent resuscitation. Resuscitation is similar to that for adults, including pain control, airway management, and administration of intravenous fluid. However, in pediatrics, fluid resuscitation is needed for burns greater than or equal to 15% of total body surface area (TBSA) compared with burns greater than or equal to 20% TBSA for adults. Unique to pediatrics is the additional assessment for non-accidental injury and accurate calculation of the percentage of total burned surface area (TBSA) in children with changing body proportions are crucial to determine resuscitation parameters, prognosis, and disposition.

Early Mobilization in Lower Extremity Frostbite Injury: Preliminary Experience at a Single Burn Center.

Cold exposure that leads to frostbite puts patients at high risk for extremity amputations. Recent treatment advances, such as thrombolytic administration, have decreased amputation rates. However, little is known about patient outcomes with early mobilization of affected limbs. A retrospective review of 41 patients admitted for lower extremity frostbite was performed at an urban hospital burn unit. All patients received the institution's standard frostbite treatment protocol. The study group was allowed to bear weight within 72 hours, while the control group was immobilized beyond this time frame. No significant differences were found between groups when comparing total tissue loss, complications, or hospital length of stay. Previous treatment of frostbite at our institution involved strict avoidance of weight bearing to the affected extremity due to concern for repeat trauma and associated complications. Our findings show that patients who ambulated sooner had comparable outcomes to those immobilized for longer time periods. Larger studies would be useful to determine a standard time to mobilization in frostbite treatment protocols.

Time Matters in Severe Frostbite: Assessment of Limb/Digit Salvage on the Individual Patient Level.

Severe frostbite is associated with high levels of morbidity through loss of digits or limbs. The aim of this study was to examine the salvage rate following severe frostbite injury. Frostbite patients from 2006 to 2014 were identified in the prospectively maintained database at a single urban burn and trauma center. Patients with imaging demonstrating a lack of blood flow in limbs/digits were included in the analysis (N = 73). The Hennepin Frostbite Score was used to quantify frostbite injury and salvage. This score provides a single value to assess each individual patient's salvage rate. The majority of patients with perfusion deficits were male (80%) with an average age of 42 years (range 11-83 years). Patients requiring amputation tended to be older (P = .002), have more tissue impacted by frostbite (P < .001), and experienced a longer time from rewarming to thrombolytic therapy (P = .001). A majority of patients (62%) received thrombolytic treatment. The percentage of patients requiring amputation was lower and the salvage rate was higher in patients treated with thrombolytics; however, the differences failed to reach statistical significance (P = .092 and P = .061, respectively). The rate of salvage decreases as the time from rewarming to thrombolytic therapy increases. Regression analysis demonstrates an additional 26.8% salvage loss with each hour of delayed treatment (P = .006). When the amount of tissue at risk for amputation is included in the model, each hour delay in thrombolytic treatment results in a 28.1% decrease in salvage (P = .011). This study demonstrates a significant decrease in limb/digit salvage with each hour of delayed administration of thrombolytics in patients with severe frostbite.

The Impact of a Universal Decolonization Protocol on Hospital-Acquired Methicillin-Resistant Staphylococcus aureus in a Burn Population.

Hospital-acquired (HA) methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of HA infections and a significant concern for burn centers. The use of 2% chlorhexidine-impregnated wipes and nasal mupirocin significantly decreases the rate of HA-MRSA in adult intensive care units. The aim of this study was to examine the impact of universal decolonization on the rate of MRSA conversion in an American Burn Association verified adult and pediatric burn center. Universal decolonization protocol consisting of daily chlorhexidine baths and a 5-day course of nasal mupirocin was implemented in the burn unit. MRSA screening both on admission and weekly and contact isolation practices were in place in pre-decolonization and post-decolonization periods. Patient data were analyzed 2 years before and 1 year after implementation of the protocol. The incidence rate of MRSA was significantly decreased after the implementation of the decolonization protocol (11.8 vs 1.0 per 1000 patient days, P < .001). Secondary to the loss of the skin barrier and suppressed immune systems, burn patients are at greater risk for invasive infection leading to severe complications and death. The prevalence of HA-MRSA at our institution's burn center was significantly decreased after the implementation of a universal decolonization protocol.

The Hennepin Score: Quantification of Frostbite Management Efficacy.

For those at risk for cold-related injury, frostbite contributes significant morbidity through loss of limbs and digits. Frostbite injury generally affects distal extremities first and spreads proximally as the time of exposure increases. The Hennepin score is a tool to quantify injury and tissue loss of frostbite injury, similar to TBSA calculators in burn patients. Application of the Hennepin score allows for a clear picture of the effect of treatment through calculation of a salvage rate. The authors found high reliability between raters using the Hennepin score worksheet, suggesting consistency with applying the score to frostbite injury and outcomes (intraclass correlation, 0.93; confidence interval, 0.88-0.97). The Hennepin score allows for a standard means to accurately measure injury and outcomes, which will aid in the study of treatment outcomes of frostbite injuries.