Exertional Heat Illness-From Identifying Heat Rash to Treating Heat Stroke.

Heat-related illness commonly affects adolescent patients, especially as summer approaches and global temperature extremes worsen. Basic counseling on sunburn prevention can decrease the risk for future malignancies, and rapidly preventing, identifying, and treating heat stroke can prevent severe morbidity and mortality. This article will review the epidemiology of exertional heat-related illness and the variations in presentations and pathology, from heat rash and sunburn to heat exhaustion and heat stroke. By the end of this review clinicians should be able to identify and treat different heat-related illnesses in adolescents and potentially save a life. [Pediatr Ann. 2024;53(1):e17-e21.].

Diagnostic Significance of Combined Calcitoninogen, Platelet, and D-Dimer Assay in Severe Heatstroke: with Clinical Data Analysis of 70 Patients with Severe Heatstroke.

The significance of calcitoninogen detection among inpatients was discussed by analyzing the clinical characteristics of severe heatstroke (HS). HS patients who were admitted to the Second Hospital of Nantong University, Jiangsu Province, China, between July 1, 2015, and October 30, 2020, were reviewed. Patients' clinical characteristics and laboratory data were recorded, and they were divided into three groups, that is, a control group (heat cramps and heat exhaustion), an exertional HS (EHS) group, and a classical HS (CHS) group to compare the differences among them. Receiver operating characteristic (ROC) curves were plotted to evaluate patients' clinical utility. (1) The body temperatures in the EHS and CHS groups were significantly higher than in the control group (all p < 0.05). (2) The D-dimer (DD), procalcitonin (PCT), and Acute Physiology and Chronic Health Evaluation (APACHE) II score of the EHS group were significantly higher compared with the control and CHS groups (all p < 0.05); the platelets (PLT), C-reactive protein (CRP), blood sodium (Na), and intravenous glucose (GLU) of the EHS group were lower than in the control and CHS groups (all p < 0.05). (3) The ROC curve analysis showed the performance results for DD (area under the curve [AUC] 0.670, 95% confidence interval [CI] 0.547-0.777), PCT (AUC 0.705, 95% CI 0.584-0.808), and PLT (AUC 0.791, 95% CI 0.677-0.879). The sensitivity was 40.48%, 100%, and 73.81%, and the specificity was 96.43%, 32.14%, and 78.57%, respectively. Using three combined analyses, an elevated AUC of 0.838, 95% CI 0.731-0.916, with a sensitivity of 71.43% and a specificity of 85.71%, respectively, was revealed. Patients in the EHS group had higher DD, PCT, and APACHE II values, whereas PLT, CRP, Na, and GLU were reduced. The apparent decrease in the PLT, as well as the increase in PCT and DD values, could be considered as early sensitivity indicators of severe HS. A combined test of these three indicators presented significant diagnostic value for detecting severe cases of HS.

Manifestaciones clínicas, diagnóstico y tratamiento del golpe de calor / Clinical Manifestations, Diagnosis and Management of Heat Stroke

Introducción: El golpe de calor es una enfermedad que fue descrita hace más de 2000 años, sin embargo, los cambios climáticos que se han presentado en las últimas décadas han permitido que su prevalencia esté en aumento. Se considera una entidad compleja en la cual existe un compromiso importante de la termorregulación corporal y, en consecuencia, del resto de sistemas. Objetivos: Orientar al abordaje adecuado y óptimo de conceptos clínicos, epidemiológicos, factores el riesgo, presentación clínica y repercusión sobre los diferentes sistemas. Métodos: Se realizó una revisión de la literatura científica de personas con golpe de calor, en quienes se evaluaron sus factores asociados, métodos diagnósticos y manejos terapéuticos. Se realizó una búsqueda de la literatura en las siguientes bases de datos: Pubmed/Medline, Science Direct, Scopus, DOAJ, Embase, Cochrane, Direme, Redalyc y SciELO. Conclusiones: El golpe de calor es una urgencia médica que implica un manejo rápido y óptimo dado su morbilidad y mortalidad, lo cual puede minimizarse si se cumplen los objetivos de tratamiento. El enfriamiento por inmersión en agua helada, por convección o evaporación son las medias más usadas. Evitar la falla multiorgánica es el segundo objetivo terapéutico(AU)

Introduction: Heat stroke is a disease described more than 2000 years ago; however, the climatic changes that have occurred in recent decades have allowed an increase in its prevalence. It is considered a complex entity in which there is an important compromise of body thermoregulation and, consequently, of the rest of the systems. Objectives: To define important concepts concerning heat stroke, risk factors, clinical presentation and repercussions on the different systems, as well as to guide an appropriate and optimal management. Methods: A review of the scientific literature about people with heat stroke was carried out to assess its associated factors, diagnostic methods and therapeutic management. A literature search was performed in the following databases: Pubmed/Medline, Science Direct, Scopus, DOAJ, Embase, Cochrane, Bireme, Redalyc, and SciELO. Conclusions: Heat stroke is a medical emergency that requires rapid and optimal management given its morbidity and mortality, which can be minimized if management goals are met. Cooling by immersion into ice water, convection or evaporation are the most commonly used measures. Avoidance of multiorgan failure is the second therapeutic objective(AU)

Heat Stroke as a Cause of Liver Failure and Evaluation of Liver Transplant.

Heat stroke is a multiple organ dysfunction syndrome of poorly understood pathogenesis. Exertional heat stroke with acute liver failure is a rarely reported condition. Liver transplant has been recommended as treatment in cases of severe liver dysfunction; however, there are only 5 described cases of long-term survival after this procedure in patients with heat stroke. Here, we present 2 cases of young athletes who developed heat stroke. Both patients developed acute liver failure and were listed for liver transplant. Liver function tests of one patient improved, and he was discharged on postoperative day 13. The other patient showed no signs of improvement and liver biopsy showed massive necrosis. The patient underwent combined kidney-liver transplant and was discharged on postoperative day 17. After a follow-up of longer than 6 years, both patients are doing well with normal liver function and no neurologic sequelae. We also reviewed all published cases of hepatic failure associated with heat stroke and found 9 published cases of liver transplant for heat stroke in the English literature. Conservative management appears to be justified in heat stroke-associated liver failure, even in the presence of accepted criteria for emergency liver transplant. If the liver does not show signs of recovery and hepatic decompensation progresses, liver transplant should be performed.

Exertional heat stroke in an amateur runner - Challenges in diagnostics and the role of unhealthy competition.

Exertional heat stroke (EHS) is a potentially life-threatening condition with a variety of symptoms and abnormal laboratory findings. Nevertheless, data evaluating the course of making an EHS diagnosis in real-life practice, as well as the role of predisposing psychological components are limited. Thus, the aim of our study was to present a multi-faceted differentiation process and show the role of unhealthy competition in the development of EHS. We describe a case of a young amateur runner, admitted to the hospital due to loss of consciousness, further mental confusion, and increased body temperature above 40°C. Head scans excluded brain haemorrhage and stroke. Elevated troponin I levels suggested an acute coronary syndrome (ACS) or myocarditis. An increase of procalcitonin levels, signs of rhabdomyolysis and severe liver injury resulted in evaluation for infection and acute hepatic damage. Subsequently, the patient's negative results pointed us to a diagnosis of EHS. In-depth anamnesis revealed that the patient's excessive effort during the race was linked to the male-female competition. EHS can present diagnostic challenges, as it mimics various diseases, such as stroke, myocarditis, ACS, infection, or liver dysfunction. In addition, the role of psychological components, such as unhealthy competition, in the development of EHS should be considered.

Overlapping Mechanisms of Exertional Heat Stroke and Malignant Hyperthermia: Evidence vs. Conjecture.

Exertional heat stroke (EHS) and malignant hyperthermia (MH) are life-threatening conditions, triggered by different environmental stimuli that share several clinical symptoms and pathophysiological features. EHS manifests during physical activity normally, but not always, in hot and humid environments. MH manifests during exposure to haloalkane anesthetics or succinylcholine, which leads to a rapid, unregulated release of calcium (Ca2+) within the skeletal muscles inducing a positive-feedback loop within the excitation-contraction coupling mechanism that culminates in heat stroke-like symptoms, if not rapidly recognized and treated. Rare cases of awake MH, independent of anesthesia exposure, occur during exercise and heat stress. It has been suggested that EHS and MH are mediated by similar mechanisms, including mutations in Ca2+ regulatory channels within the skeletal muscle. Rapid cooling, which is the most effective treatment for EHS, is ineffective as an MH treatment; rather, a ryanodine receptor antagonist drug, dantrolene sodium (DS), is administered to the victim to prevent further muscle contractions and hyperthermia. Whether DS can be an effective treatment for EHS victims remains uncertain. In the last decade, multiple reports have suggested a number of mechanistic links between EHS and MH. Here, we discuss aspects related to the pathophysiology, incidence, diagnosis and treatment. Furthermore, we present evidence regarding potential overlapping mechanisms between EHS and MH and explore current knowledge to establish what is supported by evidence or a lack thereof (i.e. conjecture).

Controversies in exertional heat stroke diagnosis, prevention, and treatment.

During the past several decades, the incidence of exertional heat stroke (EHS) has increased dramatically. Despite an improved understanding of this syndrome, numerous controversies still exist within the scientific and health professions regarding diagnosis, pathophysiology, risk factors, treatment, and return to physical activity. This review examines the following eight controversies: 1) reliance on core temperature for diagnosing and assessing severity of EHS; 2) hypothalamic damage induces heat stroke and this mediates "thermoregulatory failure" during the immediate recovery period; 3) EHS is a predictable condition primarily resulting from overwhelming heat stress; 4) heat-induced endotoxemia mediates systemic inflammatory response syndrome in all EHS cases; 5) nonsteroidal anti-inflammatory drugs for EHS prevention; 6) EHS shares similar mechanisms with malignant hyperthermia; 7) cooling to a specific body core temperature during treatment for EHS; and 8) return to physical activity based on physiological responses to a single-exercise heat tolerance test. In this review, we present and discuss the origins and the evidence for each controversy and propose next steps to resolve the misconception.

Round Table on Malignant Hyperthermia in Physically Active Populations: Meeting Proceedings.

CONTEXT: Recent case reports on malignant hyperthermia (MH)-like syndrome in physically active populations indicate potential associations among MH, exertional heat stroke (EHS), and exertional rhabdomyolysis (ER). However, an expert consensus for clinicians working with these populations is lacking. OBJECTIVE: To provide current expert consensus on the (1) definition of MH; (2) history, etiology, and pathophysiology of MH; (3) epidemiology of MH; (4) association of MH with EHS and ER; (5) identification of an MH-like syndrome; (6) recommendations for acute management of an MH-like syndrome; (7) special considerations for physically active populations; and (8) future directions for research. SETTING: An interassociation task force was formed by experts in athletic training, exercise science, anesthesiology, and emergency medicine. The "Round Table on Malignant Hyperthermia in Physically Active Populations" was convened at the University of Connecticut, Storrs, September 17-18, 2015. CONCLUSIONS: Clinicians should consider an MH-like syndrome when a diagnosis of EHS or ER cannot be fully explained by clinical signs and symptoms presented by a patient or when recurrent episodes of EHS or ER (or both) are unexplained. Further research is required to elucidate the genetic and pathophysiological links among MH, EHS, and ER.

[Malignant hyperthermia syndrome in the intensive care unit : Differential diagnosis and acute measures]. / Maligne hypertherme Syndrome auf der Intensivstation : Differenzialdiagnostik und Akutmaßnamen.

Malignant hyperthermia is a life-threatening disease caused by derangement of the autonomic nerve system and hypermetabolism of the peripheral musculature. Commonly body core temperatures of more than 40 °C will be found in this disease which is caused mostly by psychopharmacological drugs like antidepressants, neuroleptics but also antibiotics, pain killers, anti-Parkinson drugs, and volatile anesthetics. The inducers of malignant hyperthermia interact with postsynaptic receptors (serotonin, anticholinergics) or muscular intracellular structures responsible for calcium utilization (volatile anesthetics, succinylcholine). Rarely malignant hyperthermia is a consequence of mental stress or vigorous exercise and or heat. Malignant hyperthermic syndromes lead to a severe dysbalance of the autonomic nerve system accompanied by rhabdomyolysis, disseminated intravascular coagulopathy, and finally multi-organ failure. Accordingly, medical management is primarily directed to stabilize vital functions, withdrawal of the causing drug, and if possible antagonizing toxic substances. The leading symptom hyperthermia needs to be treated physically with available cooling systems.

Is It Exertional Heatstroke or Something More? A Case Report.

BACKGROUND: Heat stroke, heat-related illness, and malignant hyperthermia all present with hyperthermia. The former two are common presentations in the emergency department (ED). On the other hand, malignant hyperthermia (MH) is an uncommon but equally dangerous condition that requires prompt recognition and specific treatment with dantrolene sodium and avoidance of certain medications to reduce morbidity and mortality. Recent research focusing on nonanesthetic or exercise-induced MH has demonstrated a relationship between certain gene mutations and malignant hyperthermia susceptibility. CASE REPORT: We report the case of a 19 year-old man with a family history of MH who was treated for exertional heat stroke, but despite cooling and adequate fluid resuscitation, demonstrated worsening rhabdomyolysis that subsequently responded to the administration of dantrolene sodium. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: This case illustrates the importance of recognizing the potential relationship between exertional heat stroke and malignant hyperthermia. The overlap between heat stroke and malignant hyperthermia susceptibility has important implications in the treatment and evaluation of patients presenting with signs and symptoms of heat stroke or heat-related illness in the ED.

Heat stroke during long-term clozapine treatment: should we be concerned about hot weather?

OBJECTIVE: To describe the case of a patient with schizophrenia on clozapine treatment who had an episode of heat stroke. CASE DESCRIPTION: During a heat wave in January and February 2014, a patient with schizophrenia who was on treatment with clozapine was initially referred for differential diagnose between systemic infection and neuroleptic malignant syndrome, but was finally diagnosed with heat stroke and treated with control of body temperature and hydration. COMMENTS: This report aims to alert clinicians take this condition into consideration among other differential diagnoses, especially nowadays with the rise in global temperatures, and to highlight the need for accurate diagnosis of clinical events during pharmacological intervention, in order to improve treatment decisions and outcomes.

Heat stroke during long-term clozapine treatment: should we be concerned about hot weather? / Heat stroke durante tratamento de longo prazo com clozapina: devemos nos preocupar com o tempo quente?

Objective To describe the case of a patient with schizophrenia on clozapine treatment who had an episode of heat stroke. Case description During a heat wave in January and February 2014, a patient with schizophrenia who was on treatment with clozapine was initially referred for differential diagnose between systemic infection and neuroleptic malignant syndrome, but was finally diagnosed with heat stroke and treated with control of body temperature and hydration. Comments This report aims to alert clinicians take this condition into consideration among other differential diagnoses, especially nowadays with the rise in global temperatures, and to highlight the need for accurate diagnosis of clinical events during pharmacological intervention, in order to improve treatment decisions and outcomes.

Objetivo Descrever o caso de um paciente com esquizofrenia em tratamento com clozapina acometido por um episódio de heat stroke. Descrição do caso Durante uma onda de calor em janeiro e fevereiro de 2014, um paciente com esquizofrenia em tratamento com clozapina foi inicialmente encaminhado para diagnóstico diferencial de infecção sistêmica e síndrome neuroléptica maligna, tendo obtido o diagnóstico final de heat stroke, tratado com controle de temperatura corporal e hidratação. Comentários Este relato de caso tem como objetivo alertar os clínicos para este diagnóstico diferencial, que pode surgir com mais frequência à medida que as temperaturas globais continuarem a aumentar, e também destacar a importância da realização de um diagnóstico mais acurado, que possa melhorar as decisões de tratamento e os desfechos clínicos para os pacientes.

Is there a link between exertional heat stroke and susceptibility to malignant hyperthermia?

OBJECTIVE: The identification of a predisposition toward malignant hyperthermia (MH) as a risk factor for exertional heat stroke (EHS) remains a matter of debate. Such a predisposition indicates a causal role for MH susceptibility (MHS) after EHS in certain national recommendations and has led to the use of an in vitro contracture test (IVCT) to identify the MHS trait in selected or unselected EHS patients. The aim of this study was to determine whether the MHS trait is associated with EHS. METHODS: EHS subjects in the French Armed Forces were routinely examined for MHS after experiencing an EHS episode. This retrospective study compared the features of IVCT-diagnosed MHS (iMHS) EHS subjects with those of MH-normal EHS patients and MH patients during the 2004-2010 period. MHS status was assessed using the European protocol. RESULTS: During the study period, 466 subjects (median age 25 years; 31 women) underwent MHS status investigation following an EHS episode. None of the subjects reported previous MH events. An IVCT was performed in 454 cases and was diagnostic of MHS in 45.6% of the study population, of MH susceptibility to halothane in 18.5%, of MH susceptibility to caffeine in 9.9%, and of MH susceptibility to halothane and caffeine in 17.2%. There were no differences in the clinical features, biological features or outcomes of iMHS EHS subjects compared with those of MH-normal or caffeine or halothane MHS subjects without known prior EHS episode. The recurrence rate was 12.7% and was not associated with MH status or any clinical or biological features. iMHS EHS patients exhibited a significantly less informative IVCT response than MH patients. CONCLUSIONS: The unexpected high prevalence of the MHS trait after EHS suggested a latent disturbance of calcium homeostasis that accounted for the positive IVCT results. This study did not determine whether EHS patients have an increased risk of MH, and it could not determine whether MH susceptibility is a risk factor for EHS.

Special Considerations in Medical Screening for Participants in Remote Endurance Events.

As participation at remote endurance events increases, so does the need to screen participants for potentially problematic medical conditions, but this process has been ill-defined to date. This article aims to outline a general approach to screening and discusses common or important medical conditions that may need consideration in the screening process. Medical conditions that are considered low risk may translate to high-risk conditions in the setting of a remote and austere location. Medical directors of remote endurance events should have a familiarity with assessing risks and applying informed consent principles to participation. While there are no specific standards on medical disqualification from an event based on medical history alone, several systematic considerations should be made that allow for an assessment of risk to an individual for a specific event. The medical director and event director, in discussion with the athlete and treating clinician when appropriate, should come to a consensus on participation when high-risk medical conditions become apparent during the screening process. Both modifications and accommodations to participation may be used to mitigate both clinical and medicolegal risk and allow for participation.

[Heatstroke in dogs in southern Germany. A retrospective study over a 5.5-year period]. / Hitzschlag bei Hunden in Süddeutschland. Eine retrospektive Studie über 5,5 Jahre.

OBJECTIVE: Heatstroke is a life-threating emergency in dogs. The aim of this retrospective study was to analyse the sources of heat stroke in dogs, predisposing and prognostic factors, results of physical examination and clinical pathology as well as the course of this condition and appropriate treatment. MATERIAL AND METHODS: Patient histories of 12 dogs diagnosed with heat stroke over a 5.5-year period were analysed retrospectively. Normality was tested using the Kolmogrow-Smirnow Test and analysed using T-tests, the Chi-square test and the Mann-Whitney U-test. P-values < 0.05 were considered significant. RESULTS: Heat stroke occurred most frequently during summer, particularly in the afternoon. The most common cause of heat stroke was heat exposition in a car. Brachycephalic breeds were overrepresented. The most common clinical signs were polypnoea, tachycardia, hyperthermia and depression to prostration as well as gastrointestinal and neurological symptoms. Clinical pathology results included haemoconcentration, thrombocytopenia, hyperkalemia, prolonged activated partial thromboplastin time and azotemia. Therapies employed included oxygen application, cooling, fluid therapy and administration of gastrointestinal protectants, antiemetics and antibiotics. Duration of hospitalization was 1-6 days. The overall mortality rate was 50%. Most of the non-survivors died or were euthanized within 24-48 hours after presentation. All animals remaining alive after 3 days survived and could be discharged from hospital. CLINICAL RELEVANCE: Heat stroke is a life-threating condition, which can lead to shock, sepsis, coagulation disorders and multiorgan failure. Early recognition and appropriate treatment are important factors for a positive outcome. Furthermore, intensive monitoring and rapid therapy adaption as required are pivotal.

Golpe de calor: a propósito de un caso clínico / Heat stroke. a case report

El golpe de calor es una entidad poco frecuente y subdiagnosticada. La elevación de la temperatura corporal es la que desencadena las disfunciones metabólicas que pueden incluso llevar a la muerte. Se presenta el caso de un militar que se encontraba realizando ejercicios de infantería, durante el mes de septiembre, en días donde se produjeron condiciones climáticas extremas y desarrolla un cuadro de Disfunción Orgánica Múltiple (DOM) primaria; fue llevado al Servicio de Emergencia del Hospital de Fray Bentos, Río Negro. La evolución inicial se caracterizó por deterioro de la función neurológica, respiratoria, necesidad de ventilación mecánica, falla renal aguda y disfunción hematológica; se establecieron los diagnósticos de golpe de calor, injuria renal, rabomiólisis, insuficiencia respiratoria aguda y coagulación intravascular diseminada (CID). A pesar del tratamiento y manejo de sostén tiene una mala evolución, falleciendo a las 48 horas del ingreso. El caso nos recuerda que la exposición a condiciones de calor por arriba de la temperatura corporal, deteriora los mecanismos de control de calor corporal y metabólico. Es necesario un diagnóstico rápido y un manejo de sostén para conseguir una evolución satisfactoria.

A heat stroke is a very rare and under diagnosed entity. The rise in the body’s temperature is the element that triggers the metabolic dysfunctions that can even lead to death. A case of a soldier is presented; this soldier was training, doing his infantry exercises routine, during September, in days were extreme climate situations were happening, installing a case of primary Multiple Organ Dysfunction (MOD) syndrome. The soldier was taken to the Emergency Service in Fray Bentos’ Hospital, in Rio Negro. The initial evolution was clumsy and slowly, and the neurologic and breathing functions were worsening, with acute renal failure, and also hematological dysfunction. In addition to this, the patient was in need of mechanic ventilation. The diagnosis of temperature shock, acute renal injury, Rhabdomyolysis, acute respiratory failure and disseminated intravascular coagulation (DIC) were established. Supportive care was given to the patient, with an un satisfactory development, leading to death 48 hours after the hospital admission. This case reminds us that, the exposure to weather conditions that are over the body temperature interferes in the metabolism and the body’s mechanisms for controlling heat. A quick diagnosis and supportive care are needed in order to achieve a satisfactory evolution.

Exertional heat stroke, rhabdomyolysis and susceptibility to malignant hyperthermia.

Unexpectedly severe exertional heat stroke and rhabdomyolysis should prompt a clinician to look for susceptibility to malignant hyperthermia. We report a case of exertional heat stroke and rhabdomyolysis in a man later determined to have the malignant hyperthermia phenotype. We review the existing literature regarding this association and suggest future research that could address areas of remaining clinical uncertainty.

Human umbilical cord blood cells or estrogen may be beneficial in treating heatstroke.

This current review summarized animal models of heatstroke experimentation that promote our current knowledge of therapeutic effects on cerebrovascular dysfunction, coagulopathy, and/or systemic inflammation with human umbilical cord blood cells (HUCBCs) or estrogen in the setting of heatstroke. Accumulating evidences have demonstrated that HUCBCs provide a promising new therapeutic method against neurodegenerative diseases, such as stroke, traumatic brain injury, and spinal cord injury as well as blood disease. More recently, we have also demonstrated that post- or pretreatment by HUCBCs may resuscitate heatstroke rats with by reducing circulatory shock, and cerebral nitric oxide overload and ischemic injury. Moreover, CD34+ cells sorted from HUCBCs may improve survival by attenuating inflammatory, coagulopathy, and multiorgan dysfunction during experimental heatstroke. Many researchers indicated pro- (e.g. tumor necrosis factor-alpha [TNF-alpha]) and anti-inflammatory (e.g. interleukin-10 [IL-10]) cytokines in the peripheral blood stream correlate with severity of circulatory shock, cerebral ischemia and hypoxia, and neuronal damage occurring in heatstroke. It has been shown that intravenous administration of CD34+ cells can secrete therapeutic molecules, such as neurotrophic factors, and attenuate systemic inflammatory reactions by decreasing serum TNF-alpha but increasing IL-10 during heatstroke. Another line of evidence has suggested that estrogen influences the severity of injury associated with cerebrovascular shock. Recently, we also successfully demonstrated estrogen resuscitated heatstroke rats by ameliorating systemic inflammation. Conclusively, HUCBCs or estrogen may be employed as a beneficial therapeutic strategy in prevention and repair of cerebrovascular dysfunction, coagulopathy, and/or systemic inflammation during heatstroke.