1/4. Environmental hyperthermic infant and early childhood death: circumstances, pathologic changes, and manner of death.infant and early childhood death caused by environmental hyperthermia (fatal heat stroke) is a rare event, typically occurring in vehicles or beds. The aims of this study were to describe the demographics, circumstances, pathology, and manner of death in infants and young children who died of environmental hyperthermia and to compare these cases with those reported in the literature. Scene investigation, autopsy reports, and the microscopic slides of cases from three jurisdictions were reviewed. The subjects in 10 identified cases ranged in age from 53 days to 9 years. Eight were discovered in vehicles and 2 in beds. When the authors' cases were grouped with reported cases, the profile of those in vehicles differed from those in beds. The former were older, were exposed to rapidly reached higher temperatures, and often had more severe skin damage. The latter were mostly infants and were exposed to lower environmental temperatures. Hepatocellular necrosis and disseminated intravascular coagulation were reported in victims who survived at least 6 hours after the hyperthermic exposure. The consistent postmortem finding among nearly all victims was intrathoracic petechiae, suggesting terminal gasping in an attempt at autoresuscitation before death. The manner of death was either accident or homicide. Recommendations for the scene investigation are made.- - - - - - - - - - ranking = 1keywords = hyperthermia (Clic here for more details about this article) |
2/4. Collapse from exertional heat illness: implications and subsequent decisions.The implications of the collapse of a soldier early in an exercise from exertional heat illness (EHI) are considered. Such soldiers may be at risk from a genetic predisposition. malignant hyperthermia (MH) and isolated and improbable cases of EHI may be just two different expressions of the same mutated gene sequence. The genetics of MH are complex and present knowledge is incomplete. The use of the in vitro contraction test (IVCT) on cases of EHI, in addition to its proven role in MH, would be helpful in examining the relationship between MH and EHI. It has been shown that some soldiers collapsing with EHI may have subsequent positive IVCTs. The test, however, sometimes produces false positives and, in addition, a positive result could be a consequence of a heat insult rather than an antecedent. Further studies to establish the incidence of positive IVCTs in relatives of EHI probands, and thus test for heritability, are required. There is, at the moment, only one example of proven MH and proven EHI occurring in the same individual. dna from a 12-year-old boy who suffered MH and later died from the EHI and from his relatives showed relevant mutations as did the dna of two of three soldiers who survived EHI. Hajj pilgrims, who collapse with heat illness, do not show such mutations, but the etiology is different. The sedentary pilgrims succumbed to a very high external ambient temperature, the active soldiers to a huge output of internal metabolic heat. Only eventual advances in defining the genetics of MH and EHI will resolve the present confusion of the relationship between the two conditions. Meanwhile, there is a need to bypass considerations of the etiology of EHI and to identify the vulnerable and handicapped soldier by exposure after an interval of time to one or more exercise tolerance tests.- - - - - - - - - - ranking = 0.5keywords = hyperthermia (Clic here for more details about this article) |
3/4. Is there a link between malignant hyperthermia and exertional heat illness?Exertional heat illness (EHI) and malignant hyperthermia (MH) are two potentially lethal conditions. It has been suggested that a subset of MH susceptible persons may be predisposed to EHI. We examine the current understanding of these disorders and explore evidence of a relationship. Screening for the muscle type I ryanodine receptor gene should help clarify the relationship between MH and EHI.- - - - - - - - - - ranking = 2.5keywords = hyperthermia (Clic here for more details about this article) |
4/4. Criteria for the diagnosis of heat-related deaths: National association of Medical Examiners. Position paper. National association of Medical Examiners Ad Hoc Committee on the Definition of Heat-Related Fatalities.The National association of Medical Examiners Ad Hoc Committee on the Definition of Heat-Related Fatalities recommends the following definition of "heat-related death": a death in which exposure to high ambient temperature either caused the death or significantly contributed to it. The committee also recommends that the diagnosis of heat-related death be based on a history of exposure to high ambient temperature and the reasonable exclusion of other causes of hyperthermia. The diagnosis may be established from the circumstances surrounding the death, investigative reports concerning environmental temperature, and/or measured antemortem body temperature at the time of collapse. In cases where the measured antemortem body temperature at the time of collapse was > or = 105 degrees F (> or = 40.6 degrees C), the cause of death should be certified as heat stroke or hyperthermia. Deaths may also be certified as heat stroke or hyperthermia with lower body temperatures when cooling has been attempted prior to arrival at the hospital and/or when there is a clinical history of mental status changes and elevated liver and muscle enzymes. In cases where the antemortem body temperature cannot be established but the environmental temperature at the time of collapse was high, an appropriate heat-related diagnosis should be listed as the cause of death or as a significant contributing condition.- - - - - - - - - - ranking = 1.5keywords = hyperthermia (Clic here for more details about this article) |