Cooling of burns: Mechanisms and models

Postoperative hypothermia is associated with reduced length of stay in adult acute burn survivors

BACKGROUND

The hypermetabolic response after a burn predisposes patients to hypothermia due to dysfunction of thermoregulation. Traditionally, hypothermia is avoided actively in burn care due to reported complications associated with low body temperature. The likelihood of hypothermia with acute burn surgery is compounded by general anesthesia, exposure of wound areas and prolonged operation times. However, we find limited studies exploring the effects of perioperative hypothermia on length of stay in the adult burn population.

OBJECTIVE

To determine associations between postoperative hypothermia and hospital length of stay in adult burns patients.

METHOD

This retrospective cohort study involved patients admitted to the State Adult Burn Unit in Western Australia between 1st January 2015 to 28th February 2021. All adults who underwent surgery for acute burn, and had postoperative recovery room body temperature recorded, were included in the study. In this study, we defined normothermia as >36.5C and hypothermia as < 36.0 °C with mild, moderate, and severe hypothermia being 35.0-35.9 °C, 34.0-34.9 °C and < 34.0 °C, respectively. Patients with hyperthermia were excluded. Multivariable general linear models explored if hypothermia was independently associated with length of stay.

RESULTS

Among 1486 adult patients, 1338 (90%) were normothermic postoperatively, with temperatures >36.0C. We included 148 (10%) patients with hypothermia (temperature <36.0 °C) postoperatively. Most burns in the study population were minor: 96% had burns < 15% TBSA. Data modelling demonstrated that hypothermia was associated with a shorter length of hospital stay (coefficient = -0.129, p = 0.041).

CONCLUSION

In adult acute burn patients, postoperative hypothermia was associated with reduced length of stay after surgery. The positive results of this study indicate that a review of the core temperature targets with acute burn surgery, and timing of burn patient cooling practices in general is warranted.

Mechanisms of action behind the protective effects of proactive esophageal cooling during radiofrequency catheter ablation in the left atrium

Proactive esophageal cooling for the purpose of reducing the likelihood of ablation-related esophageal injury resulting from radiofrequency (RF) cardiac ablation procedures is increasingly being used and has been Food and Drug Administration cleared as a protective strategy during left atrial RF ablation for the treatment of atrial fibrillation. In this review, we examine the evidence supporting the use of proactive esophageal cooling and the potential mechanisms of action that reduce the likelihood of atrioesophageal fistula (AEF) formation. Although the pathophysiology behind AEF formation after thermal injury from RF ablation is not well studied, a robust literature on fistula formation in other conditions (eg, Crohn disease, cancer, and trauma) exists and the relationship to AEF formation is investigated in this review. Likewise, we examine the abundant data in the surgical literature on burn and thermal injury progression as well as the acute and chronic mitigating effects of cooling. We discuss the relationship of these data and maladaptive healing mechanisms to the well-recognized postablation pathophysiological effects after RF ablation. Finally, we review additional important considerations such as patient selection, clinical workflow, and implementation strategies for proactive esophageal cooling.

Atrioesophageal Fistula Rates Before and After Adoption of Active Esophageal Cooling During Atrial Fibrillation Ablation

BACKGROUND

Active esophageal cooling reduces the incidence of endoscopically identified severe esophageal lesions during radiofrequency (RF) catheter ablation of the left atrium for the treatment of atrial fibrillation. A formal analysis of the atrioesophageal fistula (AEF) rate with active esophageal cooling has not previously been performed.

OBJECTIVES

The authors aimed to compare AEF rates before and after the adoption of active esophageal cooling.

METHODS

This institutional review board (IRB)-approved study was a prospective analysis of retrospective data, designed before collecting and analyzing the real-world data. The number of AEFs occurring in equivalent time frames before and after adoption of cooling using a dedicated esophageal cooling device (ensoETM, Attune Medical) were quantified across 25 prespecified hospital systems. AEF rates were then compared using generalized estimating equations robust to cluster correlation.

RESULTS

A total of 14,224 patients received active esophageal cooling during RF ablation across the 25 hospital systems, which included a total of 30 separate hospitals. In the time frames before adoption of active cooling, a total of 10,962 patients received primarily luminal esophageal temperature (LET) monitoring during their RF ablations. In the preadoption cohort, a total of 16 AEFs occurred, for an AEF rate of 0.146%, in line with other published estimates for procedures using LET monitoring. In the postadoption cohort, no AEFs were found in the prespecified sites, yielding an AEF rate of 0% (P < 0.0001).

CONCLUSIONS

Adoption of active esophageal cooling during RF ablation of the left atrium for the treatment of atrial fibrillation was associated with a significant reduction in AEF rate.

ATP-induced hypothermia improves burn injury and relieves burn pain in mice

Thermal burn injury is a severe and life-threatening form of trauma that presents a significant challenge to clinical therapy. Therapeutic hypothermia has been shown to be beneficial in various human pathologies. Adenosine triphosphate (ATP) induces a hypothermic state that resembles hibernation-like suspended animation in mammals. This study investigates the potential protective role of ATP-induced hypothermia in thermal burn injury. Male C57BL/6 mice underwent a sham procedure or third-degree burn, and ATP-induced hypothermia was applied immediately or 1 h after burn injury. Our results show that ATP-induced hypothermia significantly improved burn depth progression and reduced collagen degradation. Moreover, hypothermia induced by ATP alleviated burn-induced hyperinflammatory responses and oxidative stress. Metabolomic profiling revealed that ATP-induced hypothermia reversed the shifts of metabolic profiles of the skin in burn mice. In addition, ATP-induced hypothermia relieved nociceptive and inflammatory pain, as observed in the antinociceptive test. Our findings suggest that ATP-induced hypothermia attenuates burn injury and provides new insights into first-aid therapy after thermal burn injury.

Active esophageal cooling during radiofrequency ablation of the left atrium: data review and update

INTRODUCTION

Radiofrequency (RF) ablation of the left atrium of the heart is increasingly used to treat atrial fibrillation (AF). Unfortunately, inadvertent thermal injury to the esophagus can occur during this procedure, potentially creating an atrioesophageal fistula (AEF) which is 80% fatal. The ensoETM (Attune Medical, Chicago, IL), is an esophageal cooling device that has been shown to reduce thermal injury to the esophagus during RF ablation.

AREAS COVERED

This review summarizes growing evidence related to active esophageal cooling during RF ablation for the treatment of AF. The review presents data demonstrating improved outcomes related to patient safety and procedural efficiency and suggests directions for future research.

EXPERT OPINION

The use of active esophageal cooling during RF ablation reduces esophageal injury, reduces or eliminates fluoroscopy requirements, reduces procedure duration and post-operative pain, and increases long-term freedom from arrhythmia. These effects in turn increase patient same-day discharge rates, decrease operator cognitive load, and reduce cost. These findings are likely to further accelerate the adoption of active esophageal cooling.

Effect of ice water injection toward the duodenal papilla for preventing post-ERCP pancreatitis: study protocol for a multicenter, single-blinded, randomized controlled trial (EUTOPIA study)

Background

Endoscopic retrograde cholangiopancreatography (ERCP) is an essential procedure in the diagnosis and treatment of biliopancreatic diseases. The most common adverse event of ERCP is post-ERCP pancreatitis (PEP), which can sometimes be severe. Our previous study suggested that injecting ice water at the end of ERCP suppressed PEP, and we decided to investigate this effect in a multicenter randomized controlled trial.

Methods

This study is being conducted at eight hospitals in Japan starting in April 2022. Patients undergoing ERCP will be randomized to ice water group and control group. In the ice water group, 250 ml of ice water is injected toward the papilla at the end of ERCP. The next morning, a physical examination and blood tests are performed to evaluate for the development of pancreatitis. The goal is to have 440 cases in each group.

Discussion

The main cause of PEP is thought to be papilla edema. Cooling the papilla, as everyone naturally does at the time of a burn, is expected to prevent its inflammation and edema. Various methods to suppress PEP have been reported, but so far none of them are reliable. The method we have devised is very simple, easy, and safe. We hope that our study will change the world's ERCP common practice.

Trial registration:UMIN000047528. Registered 20 April 2022, https://center6.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000053209

Management of non-severe burn wounds in children and adolescents: optimising outcomes through all stages of the patient journey

Paediatric burn injuries are common, especially in children younger than 5 years, and can lead to poor physical and psychosocial outcomes in the long term. In this Review, we aim to summarise the key factors and interventions before hospital admission and following discharge that can improve the long-term outcomes of paediatric burns. Care can be optimised through first aid treatment, correct initial assessment of burn severity, and appropriate patient referral to a burns centre. Scar prevention or treatment and patient follow-up after discharge are also essential. As most burn injuries in children are comparatively small and readily survivable, this Review does not cover the perioperative management associated with severe burns that require fluid resuscitation, or inhalational injury. Burns disproportionately affect children from low socioeconomic backgrounds and those living in low-income and middle-income countries, with ample evidence to suggest that there remains scope for low-cost interventions to improve care for those patients with the greatest burden of burn injury. Current knowledge gaps and future research directions are discussed.

Cooling the papilla with ice water in preventing post-ERCP pancreatitis (ice water challenge study)

BACKGROUND

The most common adverse event of endoscopic retrograde cholangiopancreatography (ERCP) is post-ERCP pancreatitis (PEP). The aim of this study was to investigate the efficacy of cooling the papilla with iced water to reduce PEP.

PATIENTS AND METHODS

Between December 2018 and July 2019, 100 consecutive patients with native papilla undergoing ERCP were prospectively enrolled in this study. In all patients, iced water was injected endoscopically toward the papilla via the working channel at the end of ERCP. The results were compared with 100 previous cases with native papilla that underwent ERCP under the same conditions without papilla cooling.

RESULTS

Although the difference was not significant, the incidence of PEP tended to be lower in the study group (4%) than in the control group (11%) (p = 0.060). In addition, the incidence of PEP was significantly reduced in patients who underwent biliary sphincterotomy (p = 0.033). All cases of PEP were mild.

CONCLUSIONS

Cooling the papilla with iced water injection, which is safe, easy, and cheap might reduce PEP.

Proactive esophageal cooling protects against thermal insults during high-power short-duration radiofrequency cardiac ablation

BACKGROUND

Proactive cooling with a novel cooling device has been shown to reduce endoscopically identified thermal injury during radiofrequency (RF) ablation for the treatment of atrial fibrillation using medium power settings. We aimed to evaluate the effects of proactive cooling during high-power short-duration (HPSD) ablation.

METHODS

A computer model accounting for the left atrium (1.5 mm thickness) and esophagus including the active cooling device was created. We used the Arrhenius equation to estimate the esophageal thermal damage during 50 W/ 10 s and 90 W/ 4 s RF ablations.

RESULTS

With proactive esophageal cooling in place, temperatures in the esophageal tissue were significantly reduced from control conditions without cooling, and the resulting percentage of damage to the esophageal wall was reduced around 50%, restricting damage to the epi-esophageal region and consequently sparing the remainder of the esophageal tissue, including the mucosal surface. Lesions in the atrial wall remained transmural despite cooling, and maximum width barely changed (<0.8 mm).

CONCLUSIONS

Proactive esophageal cooling significantly reduces temperatures and the resulting fraction of damage in the esophagus during HPSD ablation. These findings offer a mechanistic rationale explaining the high degree of safety encountered to date using proactive esophageal cooling, and further underscore the fact that temperature monitoring is inadequate to avoid thermal damage to the esophagus.

Procedural time reduction associated with active esophageal cooling during pulmonary vein isolation

BACKGROUND

Active esophageal cooling is increasingly utilized as an alternative to luminal esophageal temperature (LET) monitoring for protection against thermal injury during pulmonary vein isolation (PVI) when treating atrial fibrillation (AF). Published data demonstrate the efficacy of active cooling in reducing thermal injury, but impacts on procedural efficiency are not as well characterized. LET monitoring compels pauses in ablation due to heat stacking and temperature overheating alarms that in turn delay progress of the PVI procedure, whereas active esophageal cooling allows avoidance of this phenomenon. Our objective was to measure the change in PVI procedure duration after implementation of active esophageal cooling as a protective measure against esophageal injury.

METHODS

We performed a retrospective review under IRB approval of patients with AF undergoing PVI between January 2018 and February 2020. For each patient, we recorded age, gender, and total procedure time. We then compared procedure times before and after the implementation of active esophageal cooling as a replacement for LET monitoring.

RESULTS

A total of 373 patients received PVI over the study period. LET monitoring using a multi-sensor probe was performed in 198 patients, and active esophageal cooling using a dedicated device was performed in 175 patients. Patient characteristics did not significantly differ between groups (mean age of 67 years, and gender 37.4% female). Mean procedure time was 146 ± 51 min in the LET-monitored patients, and 110 ± 39 min in the actively cooled patients, representing a reduction of 36 min, or 24.7% of total procedure time (p < .001). Median procedure time was 141 [IQR 104 to 174] min in the LET-monitored patients and 100 [IQR 84 to 122] min in the actively cooled patients, for a reduction of 41 min, or 29.1% of total procedure time (p < .001).

CONCLUSIONS

Implementation of active esophageal cooling for protection against esophageal injury during PVI was associated with a significantly large reduction in procedure duration.

Prise en charge des brûlures en préhospitalier et aux urgences

Une brûlure est une lésion de la peau ou d’un autre tissu organique principalement causée par la chaleur ou les rayonnements, la radioactivité, l’électricité, la friction ou le contact avec des produits chimiques. Les plus fréquentes, les brûlures thermiques (dues à la chaleur), surviennent lorsque certaines cellules ou toutes les cellules de la peau ou d’autres tissus sont détruites par des liquides bouillants, des solides chauds (brûlures de contact), ou des flammes. En France, l’incidence des brûlures prises en charge à l’hôpital est environ de 13 pour 100 000 habitants. La prise en charge en urgence du brûlé grave par lésion thermique est bien décrite, une recommandation de pratique professionnelle a été publiée en 2019 par la Société française d’anesthésie et de réanimation, en association avec la Société francophone de brûlologie, la Société française de médecine d’urgence et l’Association des anesthésistes-réanimateurs pédiatriques d’expression française. Pourtant, l’urgentiste va être confronté à de nombreuses brûlures de gravité et de nature différentes. Nous faisons ici une mise au point sur les données connues en termes d’épidémiologie, de manifestations cliniques et des différentes thérapeutiques qui peuvent être proposées dans la prise en charge des brûlures. Nous faisons aussi le point sur les localisations à risque particulier que l’urgentiste doit connaître, ainsi que sur les intoxications qui peuvent être associées aux brûlures. Nous détaillons aussi certains contaminants qui sont à connaître.

[Target Temperature Control in Patients with Burns]

Severe burns lead to a persistent hypermetabolic response of the organism with significantly increased resting energy turnover, multi-organ dysfunction, muscle breakdown and increased risk of infection. Elevated core and skin temperatures are characteristic. A further increase in the metabolic rate can be triggered by heat losses, for which these patients are particularly predisposed due to high heat dissipation via evaporation of moisture and impairment of the thermoregulatory and insulating properties of the burnt skin. This is especially true in all treatment situations with exposure to large, uncovered skin surfaces, such as primary care, dressing changes in the intensive care unit and surgery with extensive sterile operating field. It has been shown that hypothermia is associated with numerous risks for the burn patient. Consistent heat management with measurement of the core body temperature and application of external and internal heat protection measures is recommended. Traditionally, an increase in room temperature is used here. However, this effective measure is limited by the resilience of the intensive care practitioners and the surgeons. To avoid perioperative hypothermia, strict surgical planning with limitation of the duration of surgery and close intraoperative communication about the risk of hypothermia are of particular importance.The differentiation between accepted temperature increase and infectious fever is often only possible by the inclusion of further examination findings. The criterion for sepsis is a temperature above 39 °C or below 36.5 °C.

The Practice of First Aid for Burn Injuries Among the Population of East Coast of Peninsular Malaysia for 2012-2016

Burns are a devastating public health problem that result in 10 million disability-adjusted life-years lost in low- and middle-income countries. Adequate first aid for burn injuries reduces morbidity and mortality. The rate of proper first aid practices in other countries is 12% to 22%.1,2 A 5-year retrospective audit was performed on the database of the Burn Unit in Hospital Universiti Sains Malaysia for 2012-2016; this involved 485 patients from the east coast of Malaysia. The mean age of the patients is 17.3 years old. The audit on first aid practices for burn injury showed poor practice. Out of 485 burned patients, 261 patients (53.8%) claimed that they practiced first aid. However, only 24 out of 485 patients (5%) practiced the correct first aid technique where they run their burn wound under cool water for more than 20 minutes. Two hundred and twenty-two patients had not received any first aid. Two patients did not respond to the question on the first aid usage after burn injury. The mean age of patients who practiced first aid was 15.6 years old. Out of the 261 patients who practiced first aid, 167 (64%) run their wound under tap water for different durations. Others practiced traditional remedies such as the application of "Minyak Gamat" (6.5%), soy sauce (5.5%), other ointments (3.6%), milk (1.8%), and eggs (0.7%), as well as honey, butter, and cooking oil (0.4% each). First aid practices for burn injuries in the population of east coast Malaysia are still inadequate. The knowledge and awareness of school children and the general Malaysian population must be enhanced.

Non-tuberculosis cold abscess

An 85-year-old cachectic man was found unconscious in his home. He had no specific medical history. On arrival, he was in a deep coma and hypothermic state. He had a soft mass the size of his fist in the right lower abdomen without redness or heat. Truncal computed tomography revealed subcutaneous fluid collection with gas formation. A test puncture for right lower abdominal subcutaneous fluid collection revealed pus, so an open incision was performed, with the administration of broad-spectrum antibiotics. Unfortunately, the patient died of sepsis-induced multiple organ failure. The results of abscess culture later revealed Proteus mirabilis, Escherichia coli, and Prevotella melaninogenica. This is the first report of a cold abscess induced by mixed bacteria.

Challenges in anaesthesia and pain management for burn injuries

Burn-injured patients provide unique challenges to those providing anaesthesia and pain management. This review aims to update both the regular burn anaesthetist and the anaesthetist only occasionally involved with burn patients in emergency settings. It addresses some aspects of care that are perhaps contentious in terms of airway management, fluid resuscitation, transfusion practices and pharmacology. Recognition of pain management failures and the lack of mechanism-specific analgesics are discussed along with the opioid crisis as it relates to burns and nonpharmacological methods in the management of distressed patients.

Cool Running Water First Aid Decreases Skin Grafting Requirements in Pediatric Burns: A Cohort Study of Two Thousand Four Hundred Ninety-five Children

STUDY OBJECTIVE

First-aid guidelines recommend the administration of cool running water in the early management of thermal injury. Our objective is to analyze the associations between first aid and skin-grafting requirements in children with burns.

METHODS

This cohort study used a prospectively collected registry of patients managed at a tertiary children's hospital. Multivariate logistic regression models were used to evaluate the relationship between first aid and the requirement for skin grafting. Secondary outcomes included time to re-epithelialization, wound depth, hospital admission and length of stay, and operating room interventions. Adequate first aid was defined as 20 minutes of cool running water within 3 hours of injury.

RESULTS

In our cohort of 2,495 children, 2,259 (90.6%) received first aid involving running water, but only 1,780 (71.3%) were given the adequate duration. A total of 236 children (9.5%) required grafting. The odds of grafting were decreased in the adequate first aid group (odds ratio [OR] 0.6; 95% confidence interval [CI] 0.4 to 0.8). The provision of adequate running water was further associated with reductions in full-thickness depth (OR 0.4; 95% CI 0.2 to 0.6), hospital admission (OR 0.7; 95% CI 0.3 to 0.9), and operating room interventions (OR 0.7; 95% CI 0.5 to 0.9), but not hospital length of stay (hazard ratio=0.9; 95% CI 0.7 to 1.2; P=.48).

CONCLUSION

Burn severity and clinical outcomes improved with the administration of cool running water. Adequate first aid must be prioritized by out-of-hospital and emergency medical services in the preliminary management of pediatric burns.

Effectiveness of a hydrogel dressing as an analgesic adjunct to first aid for the treatment of acute paediatric thermal burn injuries: study protocol for a randomised controlled trial

Background

Burns are a painful and traumatic experience, particularly in children. Reduced pain and anxiety positively influences re-epithelialisation rates in paediatric burn patients, however current literature fails to fully explain the effects of pain and anxiety and their links with wound healing. This study will determine if Burnaid® hydrogel dressing is an effective treatment for reducing pain in the acute period of a burn injury. It is hypothesised that a reduction in pain will then improve re-epithelialisation time in comparison to plastic wrap, which is standard practice at our institution — a metropolitan tertiary paediatric hospital located in Brisbane, Australia.

Methods/design

A randomised controlled trial will be conducted to assess the effectiveness of Burnaid® as an analgesic adjunct to cold running water first aid for the treatment of paediatric burns. Participants will include children aged between 0 and 16 years with an acute thermal burn injury (total burn surface area < 20%) presenting to the Department of Emergency within 24 h of the burn occurring. Participants will be randomised into one of two groups: (1) Burnaid® hydrogel (intervention arm) or (2) plastic wrap (control arm). Participants will also be stratified into one of two groups based on factors that influence pain intensity: (1) high pain risk or (2) low pain risk. High pain risk factors include foot burns, hot coal/ash/fire pit burns, burn area greater than 5%, and circumferential burns. The primary outcome is the intervention’s effect on reducing acute pain. Secondary outcomes include days to re-epithelialisation, pulse rate, temperature, salivary cortisol and α-amylase, anxiety, and cost-effectiveness. Sample size calculations have shown that 36 participants will be recruited into each group.

Discussion

This study will provide comprehensive data on the analgesic properties of Burnaid® as an adjunct to first aid for the treatment of acute paediatric thermal burns. If the intervention is effective in reducing pain, Burnaid® will be integrated as standard practice within the hospital’s Department of Emergency. This study replicates a real-world scenario in order to identify clinically significant analgesic and wound-healing effects.

Trial registration

Australian New Zealand Clinical Trials Registry, ACTRN12617001274369. Prospectively registered on 5 Sept 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-3057-x) contains supplementary material, which is available to authorized users.

Design and Testing of an Experimental Steam-Induced Burn Model in Rats

Background

Most of the current models for experimental burns pose difficulties in ensuring consistency and standardization.

Aim of Study

We aimed to develop an automated, reproducible technique for experimental burns using steam-based heat transfer.

Methods

The system developed for steam exposure was based on a novel, integrated, computer-controlled design. Three groups of rats were exposed to steam for 1, 3, and 7 seconds. The lesions were evaluated after 20 minutes, 48 hours, and 72 hours after burn induction.

Results

One-second steam application produced a superficial second-degree burn; three-second application induced deep second-degree burn; and seven-second application led to a third-degree burn.

Conclusion

The high level of automation of our integrated, computer-controlled system makes the difference between our system and other models, by ensuring the control of the duration of exposure, temperature, and pressure and eliminating as many potential human generated errors as possible. The automated system can accurately reproduce specific types of burns, according to histological assessment. This model could generate the reproducible data needed in the study of burn pathology and in order to assess new treatments.

A review of the evidence for threshold of burn injury

INTRODUCTION

Burn injury is common and depth is one measure of severity. Although the depth of burn injury is determined by many factors, the relationship between the temperature of the injurious agent and exposure duration, known as the time-temperature relationship, is widely accepted as one of the cornerstones of burn research. Moritz and Henriques first proposed this relationship in 1947 and their seminal work has been cited extensively. However, over the years, readers have misinterpreted their findings and incorporated misleading information about the time-temperature relationship into a wide range of industrial standards, burn prevention literature and medicolegal opinion.

AIM

The purpose of this paper is to present a critical review of the evidence that relates temperature and time to cell death and the depth of burn injury. These concepts are used by researchers, burn prevention strategists, burn care teams and child protection professionals involved in ascertaining how the mechanism of burning relates to the injury pattern and whether the injury is consistent with the history.

REVIEW METHODS

This review explores the robustness of the currently available evidence. The paper summarises the research from burn damage experimental work as well as bioheat transfer models and discusses the merits and limitations of these approaches.

REVIEW FINDINGS

There is broad agreement between in vitro and in vivo studies for superficial burns. There is clear evidence that the perception of pain in adult human skin occurs just above 43°C. When the basal layer of the epidermis reaches 44°C, burn injury occurs. For superficial dermal burns, the rate of tissue damage increases logarithmically with a linear increase in temperature. Beyond 70°C, rate of damage is so rapid that interpretation can be difficult. Depth of injury is also influenced by skin thickness, blood flow and cooling after injury. There is less clinical evidence for a time-temperature relationship for deep or subdermal burns. Bioheat transfer models are useful in research and becoming increasingly sophisticated but currently have limited practical use. Time-temperature relationships have not been established for burns in children's skin, although standards for domestic hot water suggest that the maximum temperature should be revised downward by 3-4°C to provide adequate burn protection for children.

CONCLUSION

Time-temperature relationships established for pain and superficial dermal burns in adult human skin have an extensive experimental modeling basis and reasonable clinical validation. However, time-temperature relationships for subdermal burns, full thickness burns and burn injury in children have limited clinical validation, being extrapolated from other data, and should be used with caution, particularly if presented during expert evidence.

Experimental burns: Comparison between silver sulfadiazine and photobiomodulation

Summary Objective: To analyze morphological characteristics and organization of the collagen fibers of third degree burns from scalding compared to laser therapy and silver sulfadiazine, the latter considered as the gold standard. Method: Were selected 12 animals (Rattus norvegicus) also divided into three groups (control group [CG] - untreated burns; sulfadiazine group [SG] - burns were treated with silver sulfadiazine at 1%; laser group [LG] - burns were treated with photobiomodulation). The scald burns were carried out by using PVC mold, and the material collected on the 14th day after burn was prepared for morphological and optical retardation analysis for evaluation of inflammatory infiltrates and collagen organization, respectively. Results: On the 14th day, the laser and sulfadiazine groups had mild inflammatory response, while the control group showed an intense inflammatory process, with statistical significance between laser and control groups, but not between sulfadiazine and control groups. Laser and sulfadiazine groups no longer had granulation tissue, opposite to what was seen in the control group. The presence of hair follicles and ulcer did not significantly differ between groups. The optical retardation of collagen fibers was higher in sulfadiazine group, followed by laser and control groups. As for systemic effect, we were able to identify it by simply analyzing the presence or absence of granulation tissue. Conclusion: Morphologically, the laser or silver sulfadiazine treatments were similar and both provided better organization of collagen fibers in relation to the untreated group. However, the sulfadiazine group modulated the deposition of collagen fibers more efficiently than the laser group.

Comparison of three cooling methods for burn patients: A randomized clinical trial

Tap water may not be readily available in numerous places as a first aid for burns and, therefore, tea tree oil products are recommended alternatives. Our aim in this study was to compare the cooling effects of three burn-cooling methodologies, running tap water, Burnshield^®, and Burn Cool Spray^®, and suggest indications for each cooling method. This randomized, controlled, study enrolled patients with burns who used the emergency service of Seoul Bestian Hospital from June 2015 to October 2015. The allocation of the cooling methods was randomly generated using a computer. We cooled the burn wounds by applying one of the three methods and measured the skin surface temperature and pain level using a visual analog scale (VAS) scoring. Ninety-six patients were enrolled in this study. The variability in the median(IQR) skin temperatures of the three groups was from 33.5°C (31.5-35.0) to 28.7°C (25.9-30.9), 33.8°C (32.0-35.4) to 33.2°C (30.5-35.0), and 34.0°C (32.0-35.1) to 34.4°C (32.7-35.6) for the tap water, Burn Cool Spray^®, and Burnshield^®, respectively. The variability of the mean VAS pain scores was 6.9 to 4.8 (tap water), 5.6 to 4.5 (Burn Cool Spray^®), and 5.5 to 3.3 (Burnshield^®). The reduction of skin surface temperature by tap water was significantly greater than that by the other two methods. All three methods reduced the VAS pain score after 20min of treatment (p<0.001). The tap water had a similar effect to that of the Burn Cool Spray^® but significantly better than that of Burnshield^®. There was a significant difference in the skin surface temperature and VAS pain score reduction (p=0.014 and p=0.007, respectively) between the groups cooled by tap water below and above 24°C. The patients who visited the center within 30min showed a significantly higher skin temperature than those who came after 30min did (p=0.033). Tap water and Burn Cool Spray^® reduced the skin surface temperature, but the Burnshield^® slightly increased it. All three cooling methods were effective in relieving pain. The temperature of the tap water used was related to the reduction in skin surface temperature and VAS pain score. The patients who visited the hospital within 30min of their burn accident needed a longer cooling time to attain a comparable skin surface temperature to those who visited after 30min.