Yuval Heled

Sepsis, septic shock, and fatal exertional heat stroke

Exertional heat stroke (EHS) is a clinical syndrome of hyperthermia, encephalopathy, and multiorgan dysfunction that can be irreversible and fatal. While prompt recognition and immediate, aggressive total body cooling can prevent progression of the clinical syndrome, even a short delay can exacerbate the effects of hyperthermia-induced changes. EHS is linked to an inflammatory response that is akin to the systemic inflammatory response syndrome (SIRS). However because EHS is not a common problem in most hospital intensive care units and is not in the usual list of SIRS causes, it may be overlooked easily. Furthermore normalizing the body temperature of patients with EHS, especially when hyperthermia recognition and total body cooling are delayed, may not prevent SIRS and its clinical consequences. This narrative review focuses on the inflammatory response behind the pathway leading to EHS-associated organ pathology and recommends a new insight to possible clinical interventions beyond whole body cooling.

Fatal heat stroke in children found in parked cars: autopsy findings

AbstractA common and unfortunate cause for heat stroke-related deaths in children is entrapment in closed vehicles. The aim of this study was to analyze the pathological consequences of such grave events. Autopsy reports of all children that were brought to a national forensic medicine center after being found dead in closed vehicles over a 21-year period (1995–2015) were reviewed. Data extracted were the circumstances of the events, child age, sex, height and weight, time, date and duration of entrapment, and environmental temperatures at the time of entrapment and the autopsy findings. Eight deceased children were brought to the forensic medicine center for autopsy, and seven families consented to the procedure. Autopsy findings included diffuse petechiae and hemorrhages of serosal membranes (n = 7/7) and lung congestion (n = 3/7). Conclusion: Typical autopsy findings following classical heat stroke in children include diffuse petechiae and hemorrhages and lung involvement. These findings are similar to those reported in adults that had died following exertional heat stroke—a very different mechanism of heat accumulation. Prevention of future events can possibly be obtained by public education on the rapid heating of closed vehicles, the vulnerability of children to heat, and the caregiver role in child entrapment.What is Known:• A common and unfortunate cause for heat stroke-related deaths in children is entrapment in closed vehicles. The pathological consequences of such grave events have not been previously reported.What is New:• This study is the first to describe autopsy findings from children who were found dead in parked cars.• Autopsy findings included diffuse petechiae hemorrhages of serosal membranes and lung congestion.• These findings are identical to those seen in adults following exertional heat stroke.

Measuring body core temperature using a novel non-invasive sensor

In various jobs workers may be exposed to extreme environmental conditions and physical activities. Under these conditions it is imperative to follow body temperature in workers in order to protect them from overheating leading to heat related injuries. The Drager Double Sensor (DS) is a novel non-invasive device based on heat flux balance approach for the assessment of body core temperature [1]. The purpose of this study was to compare DS measurements to rectal temperatures and to evaluate the agreement between the two measurements.

Validation of the environmental stress index (ESI) for physiological variables

A new environmental stress index (ESI), based on ambient temperature (Ta), relative humidity (RH) and solar radiation (SR), was recently suggested as a potential substitute for the wet-bulb globe temperature (WBGT) index. The purpose of this study was to evaluate and validate ESI for three different physiological variables including rectal temperature (Tre), heart rate (HR), and sweat rate (msw). A database was taken from a previous study where 12 young men (21±1 y) served as subjects exposed to 120 min of 12 different combinations consisting of three metabolic rates (rest and treadmill walking at 5 km·h−1 at 0% and 5% grades), two clothing ensembles (BDU and protective MOPP gear) and two outdoor solar radiation levels (shade and open sky). ESI was calculated as follows: ESI=0.63Ta-0.03RH+0.002SR+0.0054(TaRH)-0.073(0.1+SR)−1. Significant differences of about 2 units (p 0.838) were found between ESI and Tre, HR, or msw. These results indicate that ESI is strongly correlated to the physiological strain, whereby higher stress is reflected in higher strain. Therefore, evaluating heat stress by ESI, which uses the more common, fast response and accurate climatic measures, becomes more predominant.