The use of e-learning in medical education for mountain rescuers concerning hypothermia

Objective: Victims of mountain accidents are often exposed to wet and cold environments which may increase the risk of hypothermia. Mountain rescuers should be able to recognize and manage hypothermia. We aimed to assess relevant knowledge in professional and volunteer mountain rescuers, as well as to evaluate the efficacy of an e-learning platform for continuing medical education. Methods: An e-learning platform was developed to provide access to updated information about hypothermia. Volunteer and professional mountain rescuers participated in an e-learning course. Pretest, post-test, and specific lesson test scores were compared. After 1 year, a follow-up course was performed. Results: In total, 187 rescuers, comprising 136 (72.7%) volunteers and 51 (27.3%) professionals, were enrolled. Ahead of the course, no difference in knowledge was found between professionals and volunteers. After the course, one's knowledge of hypothermia increased significantly (p < 0.001). The scores achieved in the field management of hypothermia were better among professional rescuers than among volunteer rescuers (p = 0.003), whereas in post-traumatic hypothermia half of the results were insufficient in both groups. Moreover, 57 rescuers repeated the course after 12 months. While professionals partially retained the achieved level of knowledge, the volunteers had dropped back to their initial level. Conclusions: The e-learning course increased the knowledge of hypothermia among mountain rescuers. The poor retention after 1 year indicates that the interval between lectures should be reduced. An e-learning platform is an effective tool for the medical education of mountain rescuers

Monitoring body temperature during moderate intensity exercise and inactive recovery in the cold: a pilot study

Exposure to cold ambient conditions during outdoor recreation can lead to significant heat loss. It is unknown how fast body temperature decreases or how fast a person could become hypothermic in cold temperatures. We present a series of pilot tests involving moderate intensity exercise and inactive recovery in the cold to monitor how body temperature changes with exposure to -10°C. The primary aim of this pilot study was to test the feasibility of the proposed protocol with the intention to design a main study. The primary questions were: (i) to what degree does body temperature increase or decrease with this protocol, (ii) whether epitympanic temperature is a suitable measure of core temperature using a recently developed, non-invasive device and (iii) if participants are able to tolerate the cold during inactive recovery. This pilot series included seven participants. After an acclimatization phase (15 minutes), participants exercised at 60% peak heart rate (20 minutes) followed by a seated, inactive recovery phase (15 minutes) in the cold. The mean ambient conditions were -10.0±0.4°C and 66.1±8.6% relative humidity and no wind. The primary findings based on the feasibility criteria were that body temperature increased while exercising at an intensity of 60% HRpeak and decreased during inactive recovery by -0.3±0.1°C (epitympanic temperature). Secondly, the agreement between epitympanic and esophageal temperature (mean difference 0.2°C, 95% confidence interval -0.5 to 0.0, p=0.095) was better than in previous studies. Finally, all participants were able to tolerate the cold and complete the study despite thermal discomfort and shivering in the recovery phase. This protocol was successful in showing small changes in body temperature during exercise and recovery in the cold, though some modifications to the current protocol are recommended to elicit a larger effect size

Efficacy of warming systems in mountain rescue : an experimental manikin study

Mountain accident casualties are often exposed to cold and windy weather. This may induce post-traumatic hypothermia which increases mortality. The aim of this study was to assess the ability of warming systems to compensate for the victim’s estimated heat loss in a simulated mountain rescue operation. We used thermal manikins and developed a thermodynamic model of a virtual patient. Manikins were placed on a mountain rescue stretcher and exposed to wind chill indices of 0 °C and - 20 °C in a climatic chamber. We calculated the heat balance for two simulated clinical scenarios with both a shivering and non-shivering victim and measured the heat gain from gel, electrical, and chemical warming systems for 3.5 h. The heat balance in the simulated shivering patient was positive. In the non-shivering patient, we found a negative heat balance for both simulated weather conditions (- 429.53 kJ at 0 °C and -1469.78 kJ at - 20 °C). Each warming system delivered about 300 kJ. The efficacy of the gel and electrical systems was higher within the first hour than later (p < 0.001). We conclude that none of the tested warming systems is able to compensate for heat loss in a simulated model of a non-shivering patient whose physiological heat production is impaired during a prolonged mountain evacuation. Additional thermal insulation seems to be required in these settings

Severe hypothermia management in mountain rescue : a survey study

Introduction: Severe hypothermia is a rare but demanding medical emergency. Although mortality is high, if well managed, the neurological outcome of survivors can be excellent. The aim of the study was to assess whether mountain rescue teams (MRTs) are able to meet the guidelines in the management of severe hypothermia, regarding their equipment and procedures. Methods: Between August and December 2016, an online questionnaire, with 24 questions to be completed using Google Forms, was sent to 123 MRTs in 27 countries. Results: Twenty-eight MRTs from 10 countries returned the completed questionnaire. Seventy-five percent of MRTs reportedly provide advanced life support (ALS) on-site and 89% are regularly trained in hypothermia management. Thirty-two percent of MRTs transport hypothermic patients in cardiac arrest to the nearest hospital instead of an Extracorporeal Life Support facility; 39% are equipped with mechanical chest compression devices; 36% measure core body temperature on-site and no MRT is equipped with a device to measure serum potassium concentration on-site in avalanche victims. Conclusions: Most MRTs are regularly trained in the treatment of severe hypothermia and provide ALS. The majority are not equipped to follow standard procedural guidelines for the treatment of severely hypothermic patients, especially with cardiac arrest. However, the low response rate—23% (28/123)—could have induced a bias

Surgical masks and filtering facepiece class 2 respirators (FFP2) have no major physiological effects at rest and during moderate exercise at 3000 m altitude. A randomised controlled trial

Background: During the COVID-19 pandemic, the use of face masks has been recommended or enforced in several situations, however their effects on physiological parameters and cognitive performance at high altitude are unknown. Methods: Eight healthy participants (four females) rested and exercised (cycling, 1 W/kg) while wearing no mask, a surgical mask, or a filtering facepiece class 2 respirator (FFP2), both in normoxia and hypobaric hypoxia corresponding to an altitude of 3000 m. Arterialised oxygen saturation (SaO2), partial pressure of oxygen (PaO2) and carbon dioxide (PaCO2), heart and respiratory rate, pulse oximetry (SpO2), cerebral oxygenation, visual analogue scales for dyspnoea and mask's discomfort were systematically investigated. Resting cognitive performance and exercising tympanic temperature were also assessed. Results: Mask use had a significant effect on PaCO2 (overall +1.2 ± 1.7 mmHg). There was no effect of mask use on all other investigated parameters except for dyspnoea and discomfort, which were highest with FFP2. Both masks were associated with a similar non-significant decrease in SaO2 during exercise in normoxia (-0.5% ± 0.4%) and, especially, in hypobaric hypoxia (-1.8% ± 1.5%), with similar trends for PaO2 and SpO2. Conclusions: Although mask use was associated with higher rates of dyspnoea, it had no clinically relevant impact on gas exchange at 3000 m at rest and during moderate exercise, and no detectable effect on resting cognitive performance. Wearing a surgical mask or an FFP2 can be considered safe for healthy people living, working, or spending their leisure time in mountains, high-altitude cities, or other hypobaric environments (e.g. aircrafts) up to an altitude of 3000 m

Avalanche survival depends on the time of day of the accident: A retrospective observational study.

INTRODUCTION We aimed to investigate the relationship between the time of the day and the probability of survival of completely buried avalanche victims. We explored the frequency of avalanche burials occurring after sunset, and described victims' characteristics, duration of burial and rescue circumstances compared to daytime avalanches. METHODS In this retrospective, observational study, we analysed avalanche data from the registry of the Swiss Institute for Snow and Avalanche Research, from 1998 to 2020. RESULTS A total of 3,892 avalanche victims were included in the analysis, with 72 of the accidents (1.85%) occurring in the nighttime. Nearly 50% of the victims involved in nighttime avalanche accidents were completely buried, compared to about 25% of victims in daytime avalanches. Completely buried victims were rescued by a companion less often at night than in the daytime (15% vs. 51%, p<.001). The search and rescue of completely buried avalanche victims took longer during the nighttime compared to the daytime (median 89 min vs 20 min, p=.002). The probability of survival decreased as the day progressed; it was highest at around midday (63.0%), but decreased at sunset (40.4%) and was the lowest at midnight (28.7%). CONCLUSIONS Avalanche accidents at night are a rare event, and probability of survival after complete burial is lower during the nighttime compared to the daytime. The most relevant reason for this is the longer duration of burial, which is explained in part by the lower rate of companion rescue and the lower rate of victim localisation with an avalanche transceiver

Effects of hypothermia, hypoxia, and hypercapnia on brain oxygenation and hemodynamic parameters during simulated avalanche burial: a porcine study.

Avalanche patients who are completely buried but still able to breathe are exposed to hypothermia, hypoxia, and hypercapnia (triple H syndrome). In a porcine model, there was no clinically relevant reduction in cerebral oxygenation during hypothermia and initial reduction of fraction of inspiratory oxygen ([Formula: see text]), as observed during hypercapnia. Hypercapnia may be the main cause of cardiovascular instability, which seems to be the major trigger for a decrease in cerebral oxygenation in triple H syndrome despite severe hypothermia

Lightning accidents in the Austrian alps - a 10-year retrospective nationwide analysis

Background: Lightning strikes are rare but potentially lethal. The risk for suffering a lightning strike in a mountain environment is unknown. The aim of this nationwide study was to analyse all lightning accidents in the Austrian Alps from 2005 to 2015, to assess the circumstances of the accident, the injury pattern as well as the outcome. Methods: From 2005 to 2015, data from the national Austrian Alpine Police database as well as the Clinical Information System of Innsbruck Medical University Hospital were searched for the keywords lightning injury, lightning strike, lightning as well as ICD-10 Code T75.0. Additionally, the archive data of Innsbruck Medical University Hospital was searched manually. Results: The Austrian Alpine Police database, containing 109.168 patients for the years 2005-2015, was screened for lightning accidents. Sixty-four patients had been hit by lightning in the Austrian Alps, 54 were male. Four persons died on scene;survival rate was 93.8%. Two deceased persons were hunters, who were killed by the same lightning strike. Sixty-three patients suffered a lightning strike while doing a recreational activity, mostly hiking (n = 55), a few hunting and only one doing occupational timberwork. Sixty-three patients suffered a lightning strike between June and August with nearly half (46.9%) of the accidents happening on a Saturday or Sunday, and mainly (95.3%) between 12:00 and 22:00 h. Discussion: Persons who perform recreational outdoor and occupational activities in an alpine environment during summer and after noon incur a higher risk of sustaining a lightning strike. The primary risk group includes young male mountaineers and hunters. The mortality rate was low