Subjective perceived risk factors of exertional heat exhaustion-related symptoms in female collegiate athletes in Japan.

Associations of exertional heat exhaustion (EHE)-related symptoms with lifestyle habits and health factors specific to female athletes, ranked by relative risks from high to low, remain elusive. Addressing this issue would benefit athletes and coaches, ensuring safer practices during summer sports activities. To address this issue, we distributed paper-based questionnaires to seven universities in Japan, and 983 respondents completed our survey. The questionnaires covered various personal characteristics, lifestyle habits, perceived health factors, perceived athletic activity, and EHE-related symptoms. In this retrospective case-control study, we analyzed the relationships of EHE-related symptoms (objective variables) with lifestyle habits, health factors, and athletic activity conditions (explanatory variables) using the partial proportional odds model. The questionnaire responses revealed that perceived dehydration, sickness, loss of appetite, perceived accumulated fatigue, perceived mental stress, lack of ambient wind, and insufficient rest breaks were positively associated with EHE-related symptoms, with relative risks ranging from high to low. Using an air conditioner during sleep and having a sleep duration of ≥ 6 h were associated with a reduced risk of EHE-related symptoms. The study results suggest that female athletes should be allowed to postpone exercise or reduce its intensity and volume based on their perceptions of dehydration, sickness, loss of appetite, accumulated fatigue, and mental stress in summer to prevent heat-related illnesses.

[5 cases of occupational heat illness].

Objective: Through the analysis of five cases of occupational heat illness caused by high temperature, we expounded the pathogenesis and summarized the clinical characteristics of heat cramp and heat exhaustion of the newly revised diagnostic criteria for occupational heat illness (GBZ41-2019), in order to prevent the occurrence of occupational heat illness to put forward controllable countermeasures. Methods: According to the occupational history, clinical diagnosis and treatment and the other relevant data submitted by five patients, the diagnosis process was analyzed and summarized. Results: Five patients developed symptoms from July to August in summer, belonging to high-temperature operation. They improved by timely treatment. The symptoms, signs and laboratory tests of the five patients were different, but they were diagnosed as occupational heat illness. Conclusion: Employers should pay attention to the high temperature protection and cooling work, and strengthen the labor protection. If patients with heat cramp and heat exhaustion were timely treated, they could basically recover. Occupational disease diagnosticians should seriously study the new diagnostic criteria of occupational disease and constantly improve their diagnostic ability.

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).

Subjective perceived risk factors of exertional heat exhaustion-related symptoms in male collegiate athletes in Japan: a case-control study.

The purpose of this study was to investigate associations between lifestyle habits, health factors, athletic activity conditions, and exertional heat exhaustion (EHE)-related symptoms among male college athletes in Japan based on a self-completed questionnaire. The paper-based questionnaires were distributed to 11 universities in Japan, and 2006 respondents completed the survey. Data of personal characteristics (age, body mass), lifestyle habits (sleep duration, use of air-conditioner while sleeping, and practice duration), perceived health factors (loss of appetite, sleep deprivation, sickness, dehydration, accumulated fatigue, and mental stress), perceived athletic activity (insufficient rest breaks, high ambient temperature, excessive humidity, strong solar radiation, lack of ambient wind, and clothing discomfort), and EHE-related symptoms (dizziness, headaches, nausea, and malaise) were collected. The association between lifestyle habits, health factors, athletic activity conditions (explanatory variables), and EHE-related symptoms (objective variables) was analyzed using the partial-proportional odds model. "Perceived dehydration" (odds ratios [ORs] 1.70-2.31, p < 0.002)," "sickness" (ORs 1.35-1.76), p < 0.001), "perceived accumulated fatigue" (ORs 1.13-1.31, p ≤ 0.001), "perceived mental stress" (ORs 1.17-1.31, p < 0.019), "lack of ambient wind" (ORs 1.12-1.19, p < 0.022), "loss of appetite" (ORs 1.16-1.23, p < 0.037), and "sleep deprivation" (ORs 1.15-1.17, p < 0.025) were positively associated with EHE-related symptoms, whereas "using an air conditioner during sleeping" (ORs 0.91, p = 0.047) during summer seasons was negatively associated. These findings suggest that athletes should be allowed to postpone or downregulate exercise intensity and/or volume based on their perceptions of dehydration, sickness, accumulated fatigue, mental stress, loss of appetite, and/or sleep deprivation in the summer to prevent heat illness.

Improvement in the diagnosis and practices of emergency healthcare providers for heat emergencies after HEAT (heat emergency awareness & treatment) an educational intervention: a multicenter quasi-experimental study.

BACKGROUND: The incidence of heat emergencies, including heat stroke and heat exhaustion, have increased recently due to climate change. This has affected global health and has become an issue of consideration for human health and well-being. Due to overlapping clinical manifestations with other diseases, and most of these emergencies occurring in an elderly patient, patients with a comorbid condition, or patients on poly medicine, diagnosing and managing them in the emergency department can be challenging. This study assessed whether an educational training on heat emergencies, defined as heat intervention in our study, could improve the diagnosis and management practices of ED healthcare providers in the ED setting. METHODS: A quasi-experimental study was conducted in the EDs of four hospitals in Karachi, Pakistan. Eight thousand two hundred three (8203) patients were enrolled at the ED triage based on symptoms of heat emergencies. The pre-intervention data were collected from May to July 2017, while the post-intervention data were collected from May to July 2018. The HEAT intervention, consisting of educational activities targeted toward ED healthcare providers, was implemented in April 2018. The outcomes assessed were improved recognition-measured by increased frequency of diagnosing heat emergencies and improved management-measured by increased temperature monitoring, external cooling measures, and intravenous fluids in the post-intervention period compared to pre-intervention. RESULTS: Four thousand one hundred eighty-two patients were enrolled in the pre-intervention period and 4022 in the post-intervention period, with at least one symptom falling under the criteria for diagnosis of a heat emergency. The diagnosis rate improved from 3% (n = 125/4181) to 7.5% (n = 7.5/4022) (p-value < 0.001), temperature monitoring improved from 0.9% (n = 41/4181) to 13% (n = 496/4022) (p-value < 0.001) and external cooling measure (water sponging) improved from 1.3% (n = 89/4181) to 3.4% (n = 210/4022) (p-value < 0.001) after the administration of the HEAT intervention. CONCLUSION: The HEAT intervention in our study improved ED healthcare providers' approach towards diagnosis and management practices of patients presenting with health emergencies (heat stroke or heat exhaustion) in the ED setting. The findings support the case of training ED healthcare providers to address emerging health issues due to rising temperatures/ climate change using standardized treatment algorithms.

Changes in gastrointestinal cell integrity after marathon running and exercise-associated collapse.

PURPOSE: Endurance exercise and hyperthermia are associated with compromised intestinal permeability and endotoxaemia. The presence of intestinal fatty acid-binding protein (I-FABP) in the systemic circulation suggests intestinal wall damage, but this marker has not previously been used to investigate intestinal integrity after marathon running. METHODS: Twenty-four runners were recruited as controls prior to completing a standard marathon and had sequential I-FABP measurements before and on completion of the marathon, then at four and 24 h later. Eight runners incapacitated with exercise-associated collapse (EAC) with hyperthermia had I-FABP measured at the time of collapse and 1 hour later. RESULTS: I-FABP was increased immediately on completing the marathon (T0; 2593 ± 1373 ng·l-1) compared with baseline (1129 ± 493 ng·l-1; p < 0.01) in the controls, but there was no significant difference between baseline and the levels at four hours (1419 ± 1124 ng·l-1; p = 0.7), or at 24 h (1086 ± 302 ng·l-1; p = 0.5). At T0, EAC cases had a significantly higher I-FABP concentration (15,389 ± 8547 ng.l-1) compared with controls at T0 (p < 0.01), and remained higher at 1 hour after collapse (13,951 ± 10,476 ng.l-1) than the pre-race control baseline (p < 0.05). CONCLUSION: I-FABP is a recently described biomarker whose presence in the circulation is associated with intestinal wall damage. I-FABP levels increase after marathon running and increase further if the endurance exercise is associated with EAC and hyperthermia. After EAC, I-FABP remains high in the circulation for an extended period, suggesting ongoing intestinal wall stress.

Is Physiological Equivalent Temperature (PET) a superior screening tool for heat stress risk than Wet-Bulb Globe Temperature (WBGT) index? Eight years of data from the Gothenburg half marathon.

BACKGROUND: The Wet-Bulb Globe Temperature (WBGT) index is a common tool to screen for heat stress for sporting events. However, the index has a number of limitations. Rational indices, such as the physiological equivalent temperature (PET) and Universal Thermal Climate Index (UTCI), are potential alternatives. AIM: To identify the thermal index that best predicts ambulance-required assistances and collapses during a city half marathon. METHODS: Eight years (2010-2017) of meteorological and ambulance transport data, including medical records, from Gothenburg's half-marathon were used to analyse associations between WBGT, PET and UTCI and the rates of ambulance-required assistances and collapses. All associations were evaluated by Monte-Carlo simulations and leave-one-out-cross-validation. RESULTS: The PET index showed the strongest correlation with both the rate of ambulance-required assistances (R2=0.72, p=0.008) and collapses (R2=0.71, p=0.008), followed by the UTCI (R2=0.64, p=0.017; R2=0.64, p=0.017) whereas the WBGT index showed substantially poorer correlations (R2=0.56, p=0.031; R2=0.56, p=0.033). PET stages of stress, match the rates of collapses better that the WBGT flag colour warning. Compared with the PET, the WBGT underestimates heat stress, especially at high radiant heat load. The rate of collapses increases with increasing heat stress; large increase from the day before the race seems to have an impact of the rate of collapses. CONCLUSION: We contend that the PET is a better predictor of collapses during a half marathon than the WBGT. We call for further investigation of PET as a screening tool alongside WBGT.

The Role of Skeletal Muscles in Exertional Heat Stroke Pathophysiology.

The active participation of skeletal muscles is a unique characteristic of exertional heat stroke. Nevertheless, the only well-documented link between skeletal muscle activities and exertional heat stroke pathophysiology is the extensive muscle damage (e. g., rhabdomyolysis) and subsequent leakage of intramuscular content into the circulation of exertional heat stroke victims. Here, we will present and discuss rarely explored roles of skeletal muscles in the context of exertional heat stroke pathophysiology and recovery. This includes an overview of heat production that contributes to severe hyperthermia and the synthesis and secretion of bioactive molecules, such as cytokines, chemokines and acute phase proteins. These molecules can alter the overall inflammatory status from pro- to anti-inflammatory, affecting other organ systems and influencing recovery. The activation of innate immunity can determine whether a victim is ready to return to physical activity or experiences a prolonged convalescence. We also provide a brief discussion on whether heat acclimation can shift skeletal muscle secretory phenotype to prevent or aid recovery from exertional heat stroke. We conclude that skeletal muscles should be considered as a key organ system in exertional heat stroke pathophysiology.

Pesticide Exposure and Heat Exhaustion in a Migrant Agricultural Worker: A Case of Labor Trafficking.

To our knowledge, there are no published reports of heat exhaustion and pesticide exposure in a labor trafficked patient in the literature. Here we represent the case of J.C.J.L., who was labor trafficked. He presented to a local emergency department with heat exhaustion and pesticide exposure related to working conditions in a Mississippi corn field. Unfortunately, while he received medical treatment, his labor trafficking condition was missed. Emergency departments should be equipped to assess for human trafficking and connect trafficked persons with the resources they need. Emergency physicians should maintain a high index of suspicion for human trafficking among migrant workers presenting with occupation-related complaints.

Health status, heat preparation strategies and medical events among elite cyclists who competed in the heat at the 2016 UCI Road World Cycling Championships in Qatar.

PURPOSE: Assess the health status and heat preparation strategies of athletes competing in a World Cycling Championships held in hot ambient conditions (37°C, 25% relative humidity, wet-bulb-globe-temperature 27°C) and monitor the medical events arising during competition. METHODS: 69 cyclists (~9% of the world championships participants) completed a pre-competition questionnaire. Illnesses and injuries encountered by the Athlete Medical Centre (AMC) were extracted from the race reports. RESULTS: 22% of respondents reported illness symptoms in the 10 days preceding the Championships. 57% of respondents had previously experienced heat-related symptoms (cramping most commonly) while 17% had previously been diagnosed with exertional heat illness. 61% of the respondents had undergone some form of heat exposure prior to the Championships, with 38% acclimating for 5 to 30 days. In addition, several respondents declared to live in warm countries and all arrived in Qatar ~5 days prior to their event. 96% of the respondents used a pre-cooling strategy for the time trials and 74% did so before the road race (p<0.001), with ice vests being the most common. The AMC assessed 46 injuries and 26 illnesses in total, with three cyclists diagnosed with heat exhaustion. CONCLUSIONS: The prevalence of previous heat illness in elite cyclists calls for team and event organisation doctors to be trained on heat illness management, including early diagnosis and rapid on-site cooling. Some cyclists had been exposed to the heat prior to the Championships, but few had a dedicated plan, calling for additional education on the importance of heat acclimation. Pre-cooling was widely adopted.

Diagnosis and Management of Heatstroke.

Heatstroke is a life-threatening  and the most severe form of heat-related illnesses, characterized by body temperature >40ºC and central nervous system dysfunction. Heatstroke is classified into Non-Exertional Heatstroke (NEHS) and Exertional Heatstroke (EHS). The pathophysiology of heatstroke involves a combination of direct heat effects on the host, the systemic inflammatory and coagulopathic response. The diagnosis of heatstroke based on Bouchama's definition or Japan Association of Acute Medicine (JAAM) criteria. The basic principle of heatstroke management is early resuscitation and immediate cooling. Cold water immersion or convection evaporation method can be implemented based on the specific patient characteristic. Preventive strategies are early recognition by health workers, socialization to vulnerable groups and adequate acclimatization.

Heat-Related Illnesses.

Heat-related illnesses comprise a spectrum of syndromes resulting from disruption of thermoregulation in people exposed to high environmental heat. Symptoms range from heat edema and exercise-associated muscle cramps to exercise-associated collapse, heat exhaustion, and life-threatening heat stroke. Athletes, outdoor laborers, and military personnel are at greatest risk. Several intrinsic and extrinsic factors increase the risk of heat-related illness, including medical conditions, environmental factors, medication use, and inadequate acclimatization. Proper recognition and treatment are effective in preventing adverse outcomes. Management of the mildest forms of heat-related illness (e.g., heat edema, exercise-associated muscle cramps) is largely supportive, and sequelae are rare. Heat exhaustion is characterized by cardiovascular hypoperfusion and a rectal core temperature up to 104°F without central nervous dysfunction. Mild cooling, rest, and hydration are recommended. Heat stroke is a medical emergency in which patients present with rectal core temperature of 105°F or greater, multiorgan damage, and central nervous dysfunction. Ice water or cold water immersion is recommended. Patients adequately cooled within 30 minutes have excellent outcomes. Patients with heat stroke generally require hospitalization to monitor for medical complications despite rapid cooling. People diagnosed with heat stroke or severe heat-related illness should refrain from physical activity for at least seven days after release from medical care, then gradually begin activity over two to four weeks. Acclimatization, adequate hydration, and avoidance of activities during extreme heat are the most effective measures to reduce the incidence of heat-related illnesses.

Brugada Syndrome Unmasked by Heat Exhaustion.

Brugada syndrome (BrS) as an established channelopathy can be unmasked by various triggers like drugs, fever, etc. Herein, we presented a female patient in whom type 1 Brugada pattern on admission electrocardiography might be unmasked by heat exhaustion.

A mimic of sexually-motivated homicide: insect stings and heat exhaustion in a forest.

We report the case a woman who was found dead in a forest. The body was nude and the position of the body suggested a sexually motivated homicide. We concluded that death was not related to homicide, but was related to the conjunction of environmental factors, including insect stings, and acute psychosis. A medicolegal death investigation with postmortem examination was undertaken to determine cause of death. At the scene, the body was supine with legs spread apart and the knees flexed, exposing the external genitalia. There were multiple apparent bruises on the body and neck. At autopsy, based on macroscopic and microscopic examination, the apparent bruises were found to be hemorrhagic insect bites. No significant injuries were present and no semen was found. Death appeared to be related to heat exhaustion and innumerable insect stings. Investigation of the medical history revealed longstanding schizoaffective disorder with episodic psychotic decompensations. In the past, during an acute psychotic episode the decedent removed her clothing and ran wildly in a forest, until she was rescued in a state of exhaustion and marked agitation, and taken to hospital for treatment. We concluded that the same circumstances had been repeated but with a fatal outcome. This case is an example of a mimic of sexually-motivated homicide and is a reminder to forensic pathologists to avoid tunnel vision. We need to be skeptical of the allure of common sense based on first impressions of the scene and the body. Forensic pathologists must be unafraid to scientifically explore improbable, but true, alternate explanations.

Complicated malaria symptoms associated with Plasmodium vivax among patients visiting health facilities in Mendi town, Northwest Ethiopia.

BACKGROUND: Malaria is still a major health problem in some parts of the world. Plasmodium falciparum is the common pathogenic parasite and is responsible for majority of malaria associated deaths. Recently the other benign parasite, P. vivax, is reported to cause life threatening severe malaria complications. Thus, this study was aimed to assess incidence of severe malaria symptoms caused by P. vivax parasite in some malaria endemic areas of Ethiopia. MATERIALS AND METHODS: Presumptive malaria patients (all age groups) seeking medication at the selected health facilities in Mendi town, Northwest Ethiopia, were recruited for the study. Socio-demographic, clinical and parasitological characteristics were assessed following standard procedures. Data was analyzed using descriptive statistics, chi-square test and relative risk. RESULTS: Of the 384 patients enrolled in the study for P. vivax mono-infection, 55 (14.3 %) of them were fulfilled at least one of the WHO criteria for severe malaria indicators. Some of these clinical manifestations were: prostration 14 (25.45 %), persistent vomiting 9 (16.36 %), respiratory distress 6 (10.9 %), hypoglycemia 5 (9.1 %), hyperpyrexia 8 (14.5 %), and severe anemia 13 (23.63 %). Differences in parasite load did not affect the frequency of some severe malaria symptoms. However, severe anemia, prostration, and persistent vomiting were significantly affected (P < 0.05) by relatively higher load of parasitemia, (OR = 3.8, 95 % CI, 1.1-13.7; OR = 4.4, 95 % CI, 1.4-13.9; and OR = 7, 95 % CI, 1.8-27.4) respectively. CONCLUSION: P.vivax associated severe malaria symptoms observed in this study is supportive evidence for the notion that P.vivax is no longer benign parasite but rather virulent. Thus, to meet international and regional targets of malaria eradication, a holistic prevention and control approaches should be designed.

Circulatory endotoxin concentration and cytokine profile in response to exertional-heat stress during a multi-stage ultra-marathon competition.

Exertional-heat stress has the potential to disturb intestinal integrity, leading to enhanced permeability of enteric pathogenic micro-organisms and associated clinical manifestations. The study aimed to determine the circulatory endotoxin concentration and cytokine profile of ultra-endurance runners (UER, n=19) and a control group (CON, n=12) during a five stage 230km ultra-marathon (mean ± SD: 27h38min ± 3h55min) conducted in hot and dry environmental conditions (30ºC to 40ºC and 31% to 40% relative humidity). Body mass and tympanic temperature were measured, and venous blood samples were taken before (pre-stage) and immediately after (post-stage) each stage of the ultra-marathon for the analysis of gram-negative bacterial endotoxin, C-reactive protein, cytokine profile (IL-6, IL-1ß, TNF-α, IFN-γ, IL-10, and IL- 1ra), and plasma osmolality. Gastrointestinal symptoms and perceptive thermal tolerance rating were also monitored throughout competition. Mean exercise-induced body mass loss over the five stages ranged 1.0% to 2.5%. Pre- and poststage plasma osmolality in UER ranged277 to 282mOsmol/kg and 286 to 297 mOsmol/kg, respectively. Pre-stage concentrations of endotoxin (peak: 21% at Stage 5), C-reactive protein (889% at Stage 3), IL-6 (152% at Stage 2), IL-1ß (95% at Stage 5), TNF-α (168% at Stage 5), IFN-γ (102% at Stage 5),IL-10 (1271% at Stage 3), and IL-1ra (106% at Stage 5) increased as the ultra-marathon progressed in UER; while no changes in CON were observed (except for IL-1ß, 71% at Stage 5). Pre- to post-stage increases were observed for endotoxin (peak: 22% at Stage 3), C-reactive protein (25% at Stage 1), IL-6 (238% at Stage 1), IL-1ß (64% at Stage 1), TNF-α (101% at Stage 1), IFN-γ (39% at Stage 1), IL-10 (1100% at Stage 1), and IL-1ra(207% at Stage 1) concentrations in UER. Multi-stage ultra-marathon competition in the heat resulted in a modest circulatory endotoxaemia accompanied by a pronounced pro-inflammatory cytokinaemia by post-Stage 1, both of which were sustained throughout competition at rest (pre-stage) and after stage completion. Compensatory anti-inflammatory responses and other external factors (i.e., training status, cooling strategies, heat acclimatization, nutrition and hydration) may have contributed towards limiting the extent of pro-inflammatory responses in the current scenario.

Mechanisms by Which Dehydration May Lead to Chronic Kidney Disease.

Dehydration, a condition that characterizes excessive loss of body water, is well known to be associated with acute renal dysfunction; however, it has largely been considered reversible and to be associated with no long-term effects on the kidney. Recently, an epidemic of chronic kidney disease has emerged in Central America in which the major risk factor seems to be recurrent heat-associated dehydration. This has led to studies investigating whether recurrent dehydration may lead to permanent kidney damage. Three major potential mechanisms have been identified, including the effects of vasopressin on the kidney, the activation of the aldose reductase-fructokinase pathway, and the effects of chronic hyperuricemia. The discovery of these pathways has also led to the recognition that mild dehydration may be a risk factor in progression of all types of chronic kidney diseases. Furthermore, there is some evidence that increasing hydration, particularly with water, may actually prevent CKD. Thus, a whole new area of investigation is developing that focuses on the role of water and osmolarity and their influence on kidney function and health.

Heat illnesses: a hot topic in the setting of global climate change.

BACKGROUND: Heat illnesses affect a large number of people every year and are becoming an increasing cause of pathology as climate change results in increasing global temperatures. OBJECTIVE: This article will review the physiological responses to heat, as well as the pathophysiological processes that result in heat illnesses. The emphasis will be on providing general practitioners (GPs) with an understanding of how to prevent heat illness in their patients and how to predict who is most at risk. DISCUSSION: Heat illnesses may be thought of as minor or major illnesses, any of which may present to the GP. Consideration must be given to identifying those who need more critical intervention and on when to transfer for higher-level of care.