Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Heat Illness: 2019 Update

Heat-Related Illnesses

There is a growing incidence of heat-related illnesses due to rising global temperatures. Heat-related illnesses range from mild to severe, with heat stroke being the most critical. The wet bulb global temperature index considers humidity and solar intensity; its use is recommended to estimate heat stress on an individual and mitigate risk. Efficient cooling methods, such as cold water immersion, are essential in severe cases. Prevention is through hydration, appropriate clothing, recognition of high risk medications, and awareness of environmental conditions. Recognizing heat-related illnesses early in the clinical course and implementing rapid cooling strategies reduces morbidity and mortality.

Climate Change

As human-induced climate change warms the planet, its health impacts will affect all populations, but certain groups will be more vulnerable to its impacts. Given its role as a health care safety net, emergency medicine will play a crucial role in addressing these health conditions. Additionally, with its expertise in disaster medicine, interdisciplinary collaboration, and health care systems knowledge, emergency medicine has the potential to lead the health care sector's response to climate change.

Heat-related illness

ABSTRACT

This article concisely overviews heat-related illnesses, emphasizing their significant impact on public health. It explores the pathophysiology of conditions ranging from mild heat cramps to life-threatening heat stroke, highlighting key heat transfer mechanisms and the importance of environmental factors. Differential diagnosis considerations, prevention strategies, and nursing implications are discussed, underscoring the need for prompt recognition and intervention in managing these conditions.

The Intersection of Geriatrics, Climate Change, and Wilderness Medicine: Education is Critical

According to the US Census, for the first time in history, older adults are projected to exceed the number of children by 2035. These seniors are headed to the outdoors in increasing numbers and face unique risks. They benefit from careful pre-event evaluation planning to maintain their health in wilderness environments. Climate change is affecting all of us, but seniors are considered an especially vulnerable group. This vulnerability needs to be addressed not only when older adults head into the wilderness but also when the wilderness "comes to them" in areas where wilderness medicine and disaster medicine overlap. Education of both providers and patients is vital. This article aims to discuss the special needs of older adults/seniors /elders (defined as those over 65 unless otherwise indicated) in the wilderness as well as the vulnerability of older adults to climate change, both during planned wilderness activities and when the wilderness "comes to them" because of climate change, and to identify opportunities for education and adaptation of patients and education of physicians and wilderness and disaster responders to care for these older patients. The PubMed and Google Scholar Database search engines were utilized to review relevant English language publications between 2000 and 2023 that addressed individuals over 65 and explored the overlap of geriatrics (aged over 65), wilderness and disaster medicine, and climate change and create a perspective summary. Because of increased numbers of older adults heading into the wilderness for outdoor activities or having wilderness thrust upon them due to climate change, cross training of all specialties including the fields of emergency, geriatrics, wilderness medicine, and disaster medicine is needed in collaboration with other organizations and search and rescue. Response agencies must recognize that training in wilderness medicine provides a background for practitioners working in dangerous and remote settings and ought to seek out individuals with such skills when placing responders in the field. Climate change is making these intersections and the need for this education more urgent with time.

Severe Hyperthermia in Mountaineering: Coincidence of Heat Stroke and Infection

Heat illness is a condition that is sometimes seen in those undertaking physical activities. This case report focuses on a female hiker who developed heat stroke during a trek in the Dachstein region of Upper Austria. The patient's presentation was initially unclear and could only be confirmed by the use of a thermometer. This had a significant impact on the medical decision-making process during a complex rescue operation.

Management of Heat-Related Illness and Injury in the ICU: A Concise Definitive Review

OBJECTIVES

The increasing frequency of extreme heat events has led to a growing number of heat-related injuries and illnesses in ICUs. The objective of this review was to summarize and critically appraise evidence for the management of heat-related illnesses and injuries for critical care multiprofessionals.

DATA SOURCES

Ovid Medline, Embase, Cochrane Clinical Trials Register, Cumulative Index to Nursing and Allied Health Literature, and ClinicalTrials.gov databases were searched from inception through August 2023 for studies reporting on heat-related injury and illness in the setting of the ICU.

STUDY SELECTION

English-language systematic reviews, narrative reviews, meta-analyses, randomized clinical trials, and observational studies were prioritized for review. Bibliographies from retrieved articles were scanned for articles that may have been missed.

DATA EXTRACTION

Data regarding study methodology, patient population, management strategy, and clinical outcomes were qualitatively assessed.

DATA SYNTHESIS

Several risk factors and prognostic indicators for patients diagnosed with heat-related illness and injury have been identified and reported in the literature. Effective management of these patients has included various cooling methods and fluid replenishment. Drug therapy is not effective. Multiple organ dysfunction, neurologic injury, and disseminated intravascular coagulation are common complications of heat stroke and must be managed accordingly. Burn injury from contact with hot surfaces or pavement can occur, requiring careful evaluation and possible excision and grafting in severe cases.

CONCLUSIONS

The prevalence of heat-related illness and injury is increasing, and rapid initiation of appropriate therapies is necessary to optimize outcomes. Additional research is needed to identify effective methods and strategies to achieve rapid cooling, the role of immunomodulators and anticoagulant medications, the use of biomarkers to identify organ failure, and the role of artificial intelligence and precision medicine.

Wilderness Medical Society Clinical Practice Guidelines for the Prevention and Treatment of Heat Illness: 2024 Update

The Wilderness Medical Society (WMS) convened an expert panel in 2011 to develop a set of evidence-based guidelines for the recognition, prevention, and treatment of heat illness. The current panel retained 5 original members and welcomed 2 new members, all of whom collaborated remotely to provide an updated review of the classifications, pathophysiology, evidence-based guidelines for planning and preventive measures, and recommendations for field- and hospital-based therapeutic management of heat illness. These recommendations are graded based on the quality of supporting evidence and the balance between the benefits and risks or burdens for each modality. This is an updated version of the WMS clinical practice guidelines for the prevention and treatment of heat illness published in Wilderness & Environmental Medicine. 2019;30(4):S33-S46.

Injuries and medical emergencies among international travellers

BACKGROUND

Tropical infectious diseases and vaccine-preventable emergencies are the mainstay of pre-travel consultations. However, non-communicable diseases, injuries and accidents that occur during travel are not emphasized enough in these settings.

METHODS

We performed a narrative review based on a literature search of PubMed, Google Scholar, UpToDate, DynaMed and LiSSa and on reference textbooks and medical journals dedicated to travel, emergency and wilderness medicine. Relevant secondary references were extracted. We also aimed to discuss newer or neglected issues, such as medical tourism, Coronavirus Disease 2019, exacerbations of co-morbidities associated with international travel, insurance coverage, health care seeking abroad, medical evacuation or repatriation and tips for different types of travellers' emergency medical kits (personal, group, physician handled).

RESULTS

All sources reviewed led to the selection of >170 references. Among epidemiological data on morbidity and deaths while abroad, only retrospective data are available. Deaths are estimated to occur in 1 in 100 000 travellers, with 40% caused by trauma and 60% by diseases, and <3% linked to infectious diseases. Trauma and other injuries acquired during travel, such as traffic accidents and drowning, can be reduced by up to 85% with simple preventive recommendations such as avoiding simultaneous alcohol intake. In-flight emergencies occur on 1 in 604 flights on average. Thrombosis risk is two to three times greater for travellers than for non-travellers. Fever during or after travel can occur in 2-4% of travellers, but in up to 25-30% in tertiary centres. Traveller's diarrhoea, although rarely severe, is the most common disease associated with travel. Autochthonous emergencies (acute appendicitis, ectopic pregnancy, dental abscess) can also occur.

CONCLUSIONS

Pre-travel medicine encounters must include the topic of injuries and medical emergencies, such as the risk-taking behaviours and foster better planning in a comprehensive approach along with vaccines and infectious diseases advices.

An Evidence-Based Algorithm of Management of Heatstroke in the Emergency Department

Annual rates of heat illness and heat-related deaths have been increasing across the United States as more regions of the country have been experiencing heat waves of extreme ambient temperatures of prolonged durations. According to the Centers for Disease Control and Prevention, heat illnesses have become the leading cause of weather-related deaths. This article critiques and describes the findings of a systematic review by C. Rublee et al. (2021). The review was conducted to develop an evidence-based algorithm specific for management of heatstroke in the emergency department with implications for improving recognition, initiating rapid cooling, and providing supportive care to reduce patient mortality and morbidity.

Tarp-Assisted Cooling for Exertional Heat Stroke Treatment in Wildland Firefighting

INTRODUCTION

Exertional heat stroke is a life-threatening emergency necessitating immediate treatment with rapid body cooling. A field-expedient alternative may be tarp-assisted cooling, requiring only water and a tarp. The objective of this study was to compare core temperature (Tc) cooling rates of tarp-assisted cooling using the limited resources available to a wildland firefighter and the current standard care provided in wilderness settings.

METHODS

This cross-over, randomized control trial of 17 healthy individuals consisted of exercise in a 42±1°C, 32±4% relative humidity environment while wearing wildland firefighter attire, followed by cooling. Body cooling consisted of either pouring 11 L of 25±1°C water over the torso while lying supine on a tarp configured to hold water close to the individual (Tarp) or dousing the water on the participant followed by lying supine with a light breeze, current standard care in the wilderness (Current Care). Cooling occurred until Tc reached 38°C.

RESULTS

Participants walked until a similar Tc was achieved in Tarp (39.59±0.04°C) and Current Care (39.55±0.22°C; P=0.36). Core temperature cooling rate was not different between Tarp (0.076±0.042°C·min-1) and Current Care (0.088±0.046°C·min-1; P=0.41).

CONCLUSIONS

In hyperthermic individuals, Tarp did not provide a faster cooling rate compared to the current exertional heat stroke care provided in the wilderness, and both provided a slower cooling rate than that provided by the traditional method of cold water immersion (>0.20°C·min-1) to treat exertional heat stroke patients.

Multiparametric cardiac magnetic resonance reveals persistent myocardial inflammation in patients with exertional heat illness

OBJECTIVES

To explore the clinical potential of multiparametric cardiac magnetic resonance (CMR) in evaluating myocardial inflammation in patients with exertional heat illness (EHI).

METHODS

This prospective study enrolled 28 males with EHI (18 patients with exertional heat exhaustion (EHE) and 10 with exertional heat stroke (EHS)) and 18 age-matched male healthy controls (HC). All subjects underwent multiparametric CMR, and 9 patients had follow-up CMR measurements 3 months after recovery from EHI. CMR-derived left ventricular geometry, function, strain, native T1, extracellular volume (ECV), T2, T2*, and late gadolinium enhancement (LGE) were obtained and compared among different groups.

RESULTS

Compared with HC, EHI patients showed increased global ECV, T2, and T2* values (22.6% ± 4.1 vs. 19.7% ± 1.7; 46.8 ms ± 3.4 vs. 45.1 ms ± 1.2; 25.5 ms ± 2.2 vs. 23.8 ms ± 1.7; all p < 0.05). Subgroup analysis showed that ECV was higher in the EHS patients than those in EHE and HC groups (24.7% ± 4.9 vs. 21.4% ± 3.2, 24.7% ± 4.9 vs. 19.7% ± 1.7; both p < 0.05). Repeated CMR measurements at 3 months after baseline CMR showed persistently higher ECV than HC (p = 0.042).

CONCLUSIONS

With multiparametric CMR, EHI patients demonstrated increased global ECV, T2, and persistent myocardial inflammation at 3-month follow-up after EHI episode. Therefore, multiparametric CMR might be an effective method in evaluating myocardial inflammation in patients with EHI.

CLINICAL RELEVANCE STATEMENT

This study showed persistent myocardial inflammation after an exertional heat illness (EHI) episode demonstrated by multiparametric CMR, which is a potential promising method to evaluate the severity of myocardial inflammation and guide return to work, play, or duty in EHI patients.

KEY POINTS

• EHI patients showed an increased global extracellular volume (ECV), late gadolinium enhancement, and T2 value, indicating myocardial edema and fibrosis. • ECV was higher in the exertional heat stroke patients than exertional heat exhaustion and healthy control groups (24.7% ± 4.9 vs. 21.4% ± 3.2, 24.7% ± 4.9 vs. 19.7% ± 1.7; both p < 0.05). • EHI patients showed persistent myocardial inflammation with higher ECV than healthy controls 3 months after index CMR (22.3% ± 2.4 vs. 19.7% ± 1.7, p = 0.042).

Consistency and applicability of return to function guidelines in tactical-athletes with exertional heat illness. A systematic review

OBJECTIVE

To assess the consistency of return to sport and occupation recommendations following EHI provided in published clinical practice guidelines, consensus statements, position statements, and practice alerts. The agreement between medical policies governing the return to duty following EHI between the branches of the United States Armed Forces and published recommendations was assessed.

METHODS

Ovid MEDLINE, Web of Science, and CINAHL databases were searched for clinical practice guidelines and position statements published at any time that guided return to activity in individuals with EHI. Methodological quality was assessed, and the specific recommendations for clinical management were extracted. Consistency of recommendations was evaluated. Agreement between published guidelines and the policies governing return to activity in military tactical athletes with heat injury were also evaluated.

RESULTS

Guidelines developed by two civilian sports medicine societies in the United States detailing recommendations for return to function following EHI were identified. There was consistency between guidelines regarding recommendations that addressed abstinence from activity; medical follow-up; graded resumption of activity; and return to function. Pertaining military policy, contemporary regulations published in recent years reflected the recommendations provided in the professional guidelines. The greatest incongruence was noted in older military policies.

CONCLUSIONS

This systematic review highlights the need for consistent recommendations across all branches of the military and medical specialties pertaining to returning servicemembers to duty after EHI .

General Medical Emergencies in Athletes

This article focuses on the management of the most common on-field medical emergencies. As with any discipline in medicine, a well-defined plan and systematic approach is the cornerstone of quality health care delivery. In addition, the team-based collaboration is necessary for the safety of the athlete and the success of the treatment plan.

First-Trimester Pregnancy: Considerations for Wilderness and Remote Travel

Women increasingly participate in outdoor activities in wilderness and remote environments. We performed a literature review to address diagnostic and therapeutic considerations during first-trimester pregnancy for remote multiday travel. Pretrip planning for pregnant patients traveling outside access to advanced medical care should include performing a transvaginal ultrasound to confirm pregnancy location and checking D rhesus status. We discuss the risk of potential travel-related infections and recommended vaccinations prior to departure based on destination. Immediate evacuation to definitive medical care is required for patients with a pregnancy of unknown location and vaginal bleeding. We propose algorithms for determining the need for evacuation and present therapeutic options for nausea and vomiting, urinary tract infections, and candidiasis in the field.

Synchronized Cardioversion Performed During Cold Water Immersion of a Heatstroke Patient

We report a case of cardioversion that was successfully performed on a patient during cold water immersion. The patient deteriorated into unstable ventricular tachycardia while being treated for heatstroke. We elected to perform synchronized cardioversion without first removing the patient from the immersion body bag. The patient survived and was discharged neurologically intact on hospital day 5. There were no evident deleterious effects to the staff, the patient, or the equipment. To our knowledge, this is the first case report in the literature demonstrating the electrical cardioversion of a patient immersed in water.

A nomogram based on lymphocyte percentage for predicting hospital mortality in exertional heatstroke patients: a 13-year retrospective study

BACKGROUND

Exertional heatstroke (EHS) is a life-threatening disease without ideal prognostic markers for predicting hospital mortality.

METHODS

This is a single-center retrospective study. Clinical data from EHS patients admitted to the Intensive Care Unit (ICU) of the General Hospital of Southern Theatre Command between January 1, 2008, and December 31, 2020, were recorded and analyzed. Univariate and multivariate logistic regression were used to identify the factors for mortality. The prediction model was developed with the prognostic markers, and a nomogram was established.

RESULTS

The study ultimately enrolled 156 patients, and 15 (9.6%) of patients died before discharge. The lymphocyte count (Lym) and percentage (Lym%) were significantly lower in non-survivors (P<0.05). The univariate and multivariate logistic regression analyses indicated that Lym% at the third day of admission (Lym% D3) (OR=0.609, 95%CI: 0.454-0.816) and hematocrit (HCT) (OR=0.908, 95%CI: 0.834-0.988) were independent protective factors for hospital mortality. A nomogram incorporating Lym% D3 with HCT was developed and demonstrated good discrimination and calibration ability. The comparison between the prediction model and scoring systems revealed that the prediction model had the largest area under the curve (AUC) (0.948, 95%CI: 0.900-0.977), with 100.00% sensitivity and 83.69% specificity, and a greater clinical net benefit.

CONCLUSION

Severe EHS patients had a higher risk of experiencing prolonged lymphopenia. A nomogram based on Lym% D3 and HCT was developed to facilitate early identification and timely treatment of patients with potentially unfavorable prognoses.

Protective effect of 5,6,7,8-Tetrahydroxyflavone on high altitude cerebral edema in rats

High altitude cerebral edema (HACE) is a potentially life-threatening disease encountered at high altitudes. However, effective methods for HACE prophylaxis are limited. Convincing evidence confirms that oxidative stress induced by hypobaric hypoxia (HH) is one of the main factors that account for the development of HACE. 5,6,7,8-Tetrahydroxyflavone (THF), a flavone with four consecutive OH groups in ring A, exhibited excellent antioxidant activity in vitro and could attenuate HH induced injury in vivo. The aim of this study was to investigate the protective effect of THF against HACE and its underlying mechanisms. THF administration significantly suppressed HH induced oxidative stress by reducing the formation of hydrogen peroxide and malondialdehyde, by increasing the levels of glutathione and superoxide dismutase in brain tissue. Simultaneously, THF administration inhibited inflammatory responses by decreasing the levels of tumor necrosis factor-α, interleukin-1β, and interleukin-6 in serum and brain tissue. In addition, THF administration mitigated the energy metabolism disorder induced by HACE as evidenced by decreased levels of lactic acid, lactate dehydrogenase and pyruvate kinase as well as increased ATP levels and ATPase activities. Furthermore, THF administration decreased the expression of matrix metalloproteinase-9, aquaporin 4, hypoxia-inducible factor-1α and vascular endothelial growth factor, which attenuated blood-brain barrier (BBB) disruption and brain edema. Additionally, THF administration improved HACE induced cognitive dysfunction. These results show that THF is a promising agent in the prevention and treatment of HACE.

Wilderness Medicine: Impacts from the Weather, Water, and World

Pediatricians play an important role in the prevention of injuries and provide families with anticipatory guidance regularly. As more families are traveling and spending time outdoors, we must be adept at providing them with knowledge and resources to set them up for success on their adventures. Prevention and preparation frequently can help limit injuries sustained in the wilderness. This article will focus specifically on injuries related to the environment (eg, cold weather injuries, heat-related illnesses) and travel location (eg, high-altitude illness, marine-related injuries, diving medicine). [Pediatr Ann. 2022;51(6):e212-217.].

Immune Cells Characteristics and Their Prognostic Effects in Exertional Heatstroke Patients: A Retrospective Cohort Study

Background

Exertional heatstroke (EHS) remains a major problem for those who take strenuous physical activity. Inflammation and immune dysfunction were thought to be crucial to the pathophysiological process of heatstroke. The present study was aimed to investigate the dynamic changes of the immune cells in patients with EHS and determine their prognostic effects to provide the clinical evidence of the above process.

Methods

This single-center retrospective cohort study collected all patients with EHS admitted to the intensive care unit (ICU) of the General Hospital of Southern Theater Command of PLA from October 2008 to May 2019. The dynamic changes of the main immune cell count and ratio were collected, including white blood cell (WBC), neutrophil, monocyte, and lymphocyte. The neutrophil-to-lymphocyte ratios (NLR) were calculated by the neutrophil count/lymphocyte count × 100%. The main outcome was 90-day mortality.

Results

A total of 189 patients were enrolled. For survivors, after 24 h, the WBC and neutrophil counts began to decrease, and they were back to normal in 72 h. In addition, the lymphocyte counts were within normal limits all the time. For non-survivors, the WBC and neutrophil counts were continuous over the normal range, while the lymphocyte count and the ratio began to decrease after 24 h and were continuously low in the following days. Receiver operating characteristic (ROC) curves analysis showed that increased neutrophils and decreased lymphocytes were associated with the poor prognosis of the patients. A prediction model based on immune cell counts and ratios was constructed, and the lymphocyte count was accounted for the maximum weight.

Conclusions

In patients with EHS, increased neutrophils and decreased lymphocytes were associated with the poor prognosis. The lymphocyte count at 72 h after admission was the most important prognostic factor.

Clinical Spectrum of Pediatric Heat Illness and Heatstroke in a North American Desert Climate

ABSTRACT

The spectrum of historical features and clinical presentations of heat illness and heatstroke in the pediatric population has received limited focus in the emergency medicine literature. The majority of published cases involve children trapped in closed spaces and adolescent athletes undergoing high-intensity training regimens in geographical regions with moderately high ambient temperatures and high humidity. There has been less research on the potential impact of extreme temperatures and radiant heat that are the hallmarks of the US southwest region. We performed a retrospective review of pediatric heat illness at our facility located in a North American desert climate.

[Lethal Heatstroke with Disseminated Intravascular Coagulopathy]

We report on a case of severe heat stroke due to extended exposure to the sun in an enclosed glass cabin of an agricultural vehicle. Patient treatment, lab results and complications are reported and we examine the current literature on heat stroke.Heat stroke is a very rare and highly severe condition mostly suffered by vulnerable individuals or individuals exposed to extreme physical strain. Per definition a heat stroke is characterized by neurological deficit (especially loss of consciousness), and a high body temperature. Most important treatment is to lower the body temperature below 40 °C as quickly as possible. The best method is cold water immersion, but there are several other physical and invasive means that can be used. If performed within 30 minutes after the beginning of the incident this treatment decreases mortality considerably.Heat damage affects every organ and organ system. Most important are neurologic deficits, cardiovascular failure, liver failure and kidney failure. The excessive heat triggers a systemic inflammatory response syndrome (SIRS) which can lead to a disseminated intravascular coagulopathy (DIC). Haemostasis is also directly affected by the elevated temperature.Besides physical cooling, there is no known specific treatment to prevent secondary damage from heat stroke. Additionally, supportive care and ICU monitoring should be applied.

Diagnostic role of urine specific gravity to detect kidney impairment on heat-exposed workers in a shoe factory in Indonesia: a cross-sectional study

OBJECTIVES

Globally, there are increasing cases of chronic kidney disease of unknown origin among heat-exposed workers. We aimed to see the kidney damages of indoor heat-exposed workers and whether urine specific gravity can predict any kidney damages.

DESIGN

A cross-sectional study.

SETTING

A shoe-making factory in West Java, Indonesia.

PARTICIPANTS

119 subjects were included. Minimum total sample size was 62. Subjects were indoor heat-exposed workers who were exposed to occupational wet-bulb globe temperature (WBGT) of 28°C-30°C for 8 hours daily with 1 hour break, 5 days a week. The inclusion criterion was healthy subjects according to the result from annual medical check-up in 2019. The exclusion criteria were subjects who were taking vitamins and/or supplements that might cause disturbance in urine specific gravity and/or hydration status, pregnant and fasting.

PRIMARY AND SECONDARY OUTCOME MEASURES

Area under the curve (AUC), sensitivity and specificity of urine specific gravity for the detection of urinary nephrin and urinary kidney injury molecule-1 (KIM-1) were analysed. Estimated glomerular filtration rate (eGFR) and quantitative albuminuria were also measured.

RESULTS

WBGT in the work area of the subject was 28°C-30°C. There were 15 (12.6%) subjects who had eGFR <90 mL/min, but ≥60 mL/min. High serum vasopressin levels were found in 79 subjects with a mean of 6.54 (95% CI 5.94 to 7.14) ng/mL. Most subjects had nephrinuria (87.4%) with preserved renal function (87.4%). Several subjects had elevated urinary KIM-1 (10.9%) and albuminuria (7.6%). AUC of urine specific gravity for increased urinary nephrin was 81.7% (95% CI 68.8% to 94.6%) and statistically significant (p<0.001). Cut-off value of ≥1.018 for urine specific gravity has sensitivity of 71.2% and specificity of 80% for detecting elevation of urinary nephrin levels.

CONCLUSION

Urine specific gravity with a cut-off value of ≥1.018 could be used to detect nephrinuria among heat-exposed workers.

COVID-19 Pandemic in Mountainous Areas: Impact, Mitigation Strategies, and New Technologies in Search and Rescue Operations

van Veelen, Michiel J., Anna Voegele, Simon Rauch, Marc Kaufmann, Hermann Brugger, and Giacomo Strapazzon. COVID-19 pandemic in mountainous areas: impact, mitigation strategies, and new technologies in search and rescue operations. High Alt Med Biol. 22:335-341, 2021.-Mitigating the spread of COVID-19, an airborne infection, can lead to delays in the prehospital response and impair the performance of search and rescue (SAR) services in mountainous and remote areas. We provide an overview of the developing epidemiological situation related to the COVID-19 pandemic in mountainous areas and review current protocols to determine their suitability for mountain rescue teams. We also discuss using novel technologies to reduce the adverse effects caused by COVID-19 mitigation strategies such as delays caused by donning personal protective equipment (PPE) and reduced rescuer performance due to impaired movement and ventilation. COVID-19 has spread even in mountainous and remote locations. Dedicated protocols for the use of PPE appropriate for SAR rescuers exerting physical effort in remote areas and using technologies such as drones, telemedicine, and localization and contact tracing applications could contribute to an effective and timely emergency response in mountainous and remote settings.

[Cardiac arrest under special circumstances]

These guidelines of the European Resuscitation Council (ERC) Cardiac Arrest under Special Circumstances are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required for basic and advanced life support for the prevention and treatment of cardiac arrest under special circumstances; in particular, specific causes (hypoxia, trauma, anaphylaxis, sepsis, hypo-/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), specific settings (operating room, cardiac surgery, cardiac catheterization laboratory, dialysis unit, dental clinics, transportation [in-flight, cruise ships], sport, drowning, mass casualty incidents), and specific patient groups (asthma and chronic obstructive pulmonary disease, neurological disease, morbid obesity, pregnancy).

Frequency of Pathological Types of Hyperthyroidism in Thyroid Scan Patients

BACKGROUND

Hyperthyroidism is a common systemic disorder where Graves' disease is known as the leading cause of the disease. Thyroid stimulating hormone, T4 and T3 antibody assay is usually performed for the diagnosis of the pathology. However, with uncertainty in the results and in order to estimate the magnitude and the exact cause of the disease, radioactive iodine uptake (RAIU) test is recommended. The aim of this study is to evaluate underlying pathology in the patients presenting hyperthyroidism using RAIU test results.

METHODS

This is a cross-sectional retrospective study conducted on the patients with hyperthyroidism referred to Shahid Madani Hospital in Khorramabad. Data regarding the biochemical analysis and RAIU test was collected from the records and a questionnaire based on demographic and clinical information was completed for each patient.

RESULTS

Of 137 patients presenting hyperthyroidism, 62.04% presented with Graves' disease, 24.08% with toxic multinodular goiter and 13.86% with toxic adenoma. 24-hour RAIU test showed that the percent of radioiodine uptake was most in toxic adenoma with 67.7%, Graves' disease 53.5% and multinodular goiter 39%, respectively. From the age-based analysis, we found that Graves' was most common in 20-30 years old individuals accounting for 34%, multinodular goiter in 50+ aged individuals with 36.3% and toxic adenoma was most prevalent in 30-40 and 50+ aged patients, with 26.3%. In our population of interest, 81.8% toxic multinodular goiter patients were females.

CONCLUSION

Our study presents the outcome of RAIU tests in hyperthyroidism based on the underlying pathologies. We also conclude, in light of other findings, that Graves' disease is the most common cause of hyperthyroidism in our population.

[Paediatric Life Support]

The European Resuscitation Council (ERC) Paediatric Life Support (PLS) guidelines are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations of the International Liaison Committee on Resuscitation (ILCOR). This section provides guidelines on the management of critically ill or injured infants, children and adolescents before, during and after respiratory/cardiac arrest.

Diagnosis and treatment of patients with heat-related illnesses

Heat stress disorders or heat-related illnesses are a kind of physiological damage that occurs when the body cannot dissipate enough heat due to its thermoregulatory dysfunction. This paper aims to summarize the latest information on the diagnosis and treatment of heat-related illnesses. Heat stress disorders come in a variety of forms including heat edema, heat rash, heat cramps, heat syncope, heat tetany, severe heat exhaustion, and life-threatening heatstroke. Major risk factors may include excessive exercise, continuous exposure to high temperatures or humid environments, lack of acclimation, excessive clothing or protective equipment, obesity, and dehydration. Additional risk factors may include the patientʼs existing medical condition, environmental and personal factors, and the use of various drugs. Mild heat-related illnesses can be treated only by supportive care such as moving patients to a cool place and laying them in a supine position while elevating their legs and loosening their clothes. However, in the case of heatstroke, quickly lowering the body temperature is an essential in reducing the mortality rate. The most effective cooling method is to immerse the entire body in ice cold water.

European Resuscitation Council Guidelines 2021: Paediatric Life Support

These European Resuscitation Council Paediatric Life Support (PLS) guidelines, are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the management of critically ill infants and children, before, during and after cardiac arrest.

European Resuscitation Council Guidelines 2021: Cardiac arrest in special circumstances

These European Resuscitation Council (ERC) Cardiac Arrest in Special Circumstances guidelines are based on the 2020 International Consensus on Cardiopulmonary Resuscitation Science with Treatment Recommendations. This section provides guidelines on the modifications required to basic and advanced life support for the prevention and treatment of cardiac arrest in special circumstances; specifically special causes (hypoxia, trauma, anaphylaxis, sepsis, hypo/hyperkalaemia and other electrolyte disorders, hypothermia, avalanche, hyperthermia and malignant hyperthermia, pulmonary embolism, coronary thrombosis, cardiac tamponade, tension pneumothorax, toxic agents), special settings (operating room, cardiac surgery, catheter laboratory, dialysis unit, dental clinics, transportation (in-flight, cruise ships), sport, drowning, mass casualty incidents), and special patient groups (asthma and COPD, neurological disease, obesity, pregnancy).

Evidence-Based Heatstroke Management in the Emergency Department

INTRODUCTION

Climate change is causing an increase in the frequency and intensity of extreme heat events, which disproportionately impact the health of vulnerable populations. Heatstroke, the most serious heat-related illness, is a medical emergency that causes multiorgan failure and death without intervention. Rapid recognition and aggressive early treatment are essential to reduce morbidity and mortality. The objective of this study was to evaluate current standards of care for the emergent management of heatstroke and propose an evidence-based algorithm to expedite care.

METHODS

We systematically searched PubMed, Embase, and key journals, and reviewed bibliographies. Original research articles, including case studies, were selected if they specifically addressed the recognition and management of heatstroke in any prehospital, emergency department (ED), or intensive care unit population. Reviewers evaluated study quality and abstracted information regarding demographics, scenario, management, and outcome.

RESULTS

In total, 63 articles met full inclusion criteria after full-text review and were included for analysis. Three key themes identified during the qualitative review process included recognition, rapid cooling, and supportive care. Rapid recognition and expedited external or internal cooling methods coupled with multidisciplinary management were associated with improved outcomes. Delays in care are associated with adverse outcomes. We found no current scalable ED alert process to expedite early goal-directed therapies.

CONCLUSION

Given the increased risk of exposure to heat waves and the time-sensitivity of the condition, EDs and healthcare systems should adopt processes for rapid recognition and management of heatstroke. This study proposes an evidence-based prehospital and ED heat alert pathway to improve early diagnosis and resource mobilization. We also provide an evidence-based treatment pathway to facilitate efficient patient cooling. It is hoped that this protocol will improve care and help healthcare systems adapt to changing environmental conditions.

Adherence of Healthcare Workers to Saudi Management Guidelines of Heat-Related Illnesses during Hajj Pilgrimage

Heat-related illnesses (HRIs), such as heatstroke (HS) and heat exhaustion (HE), are common complications during Hajj pilgrims. The Saudi Ministry of Health (MoH) developed guidelines on the management of HRIs to ensure the safety of all pilgrims. This study aimed to assess healthcare workers' (HCWs) adherence to the updated national guidelines regarding pre-hospital and in-hospital management of HRIs. This was a cross-sectional study using a questionnaire based on the updated HRI management interim guidelines for the Hajj season. Overall, compliance with HE guidelines scored 5.5 out of 10 for basic management and 4.7 out of 10 for advanced management. Medical staff showed an average to above average adherence to pre-hospital HS management, including pre-hospital considerations (7.2), recognition of HS (8.1), case assessment (7.7), stabilizing airway, breathing, and circulation (8.7), and cooling (5). The overall compliance to in-hospital guidelines for HS management were all above average, except for special conditions (4.3). In conclusion, this survey may facilitate the evaluation of the adherence to Saudi HRIs guidelines by comparing annual levels of compliance. These survey results may serve as a tool for the Saudi MoH to develop further recommendations and actions.

Emergency preparedness for heat illness in China: A cross-sectional observational study

BACKGROUND

The morbidity and mortality rates from heat illness have increased due to a higher number of heatwaves. Effective urgent care of heat illness is crucial for optimizing patient outcomes. However, few studies have examined the emergency preparedness measures required for treating such patients.

METHODS

From December 23, 2019, to January 23, 2020, a content-validated instrument containing the Perceived Emergency Preparedness Scale for heat illness (heatPEPS) was administered to emergency nurses in China through WeChat. Some of these nurses were retested two weeks later. SPSS 26, IRTPRO 4.2, and NVivo 12 Plus were used for data analysis.

RESULTS

In total, 46.4% (200/431) of the participants returned valid responses. With dichotomous scoring, a high score for heatPEPS (mean 7.29; SD 1.667) was elicited. The reduced 9-item heatPEPS had a perfect fit with the 2PL model (M₂ = 27.24, p > 0.05; RMSEA = 0.01) and acceptable internal (α = 0.68) and test-rest reliability (intraclass correlation = 0.56). Many participants (74%) were dissatisfied with their heat illness-related knowledge and skills, suggesting an area that could be improved for better emergency preparedness.

CONCLUSION

Emergency departments appear to be well-prepared; however, this is subject to social desirability bias. The 9-item heatPEPS is a reliable and valid tool to measure emergency preparedness for heat illness.

Wilderness Medical Society Clinical Practice Guidelines for the Management of Exercise-Associated Hyponatremia: 2019 Update

Exercise-associated hyponatremia (EAH) is defined by a serum or plasma sodium concentration below the normal reference range of 135 mmol·L-1 that occurs during or up to 24 h after prolonged physical activity. It is reported to occur in individual physical activities or during organized endurance events conducted in environments in which medical care is limited and often not available, and patient evacuation to definitive care is often greatly delayed. Rapid recognition and appropriate treatment are essential in the severe form to increase the likelihood of a positive outcome. To mitigate the risk of EAH mismanagement, care providers in the prehospital and in hospital settings must differentiate from other causes that present with similar signs and symptoms. EAH most commonly has overlapping signs and symptoms with heat exhaustion and exertional heat stroke. Failure in this regard is a recognized cause of worsened morbidity and mortality. In an effort to produce best practice guidelines for EAH management, the Wilderness Medical Society convened an expert panel in May 2018. The panel was charged with updating the WMS Practice Guidelines for Treatment of Exercise-Associated Hyponatremia published in 2014 using evidence-based guidelines for the prevention, recognition, and treatment of EAH. Recommendations are made based on presenting with symptomatic EAH, particularly when point-of-care blood sodium testing is unavailable in the field. These recommendations are graded on the basis of the quality of supporting evidence and balanced between the benefits and risks/burdens for each parameter according to the methodology stipulated by the American College of Chest Physicians.

A body bag can save your life: a novel method of cold water immersion for heat stroke treatment

Non-exertional heat stroke is a life-threatening condition characterized by passive exposure to high ambient heat, a core body temperature of 40°C (104°F) or greater, and central nervous system dysfunction. Rapid cooling is imperative to minimize mortality and morbidity. Although evaporative and convective measures are often used for cooling heat stroke patients, cold water immersion produces the fastest cooling. However, logistical difficulties make cold water immersion challenging to implement in the emergency department. To our knowledge, there is no documented case utilizing a body bag (ie, human remains pouch) as a cold water immersion tank for rapid resuscitation of heat stroke. During a regional heat wave an elderly woman was found unconscious in a parking lot with an oral temperature of 40°C (104°F) and altered mental status. She was cooled to 38.4°C (101.1°F) in 10 minutes by immersion in an ice- and water-filled body bag. The patient rapidly regained normal mentation and was discharged home from the ED. This case highlights a novel method for efficient and convenient cold water immersion for heat stroke treatment in the emergency department.