Cause of Death in Utah Avalanche Fatalities, 2006-2007 through 2017-2018 Winter Seasons.

INTRODUCTION: Understanding patterns of avalanche fatalities can aid prevention and rescue strategies. In 2007, we published a report reviewing avalanche deaths in Utah between the 1989-1990 and 2005-2006 winter seasons. In the current report, we discuss Utah avalanche fatalities from the 2006-2007 to 2017-2018 seasons. METHODS: Avalanche fatality data were obtained from the Utah Avalanche Center and Utah State Office of the Medical Examiner. Autopsy reports were reviewed to determine demographic information, type of autopsy (external vs internal), injuries, and cause of death. RESULTS: Thirty-two avalanche deaths occurred in Utah during the study period. The mean (±SD) age of victims was 32±13 (8-54) y. Thirty victims (94%) were male and 2 (6%) were female. Seventy-two percent of deaths were from asphyxiation, 19% from trauma alone, and 9% from a combination of asphyxiation and trauma. Snowmobilers accounted for the largest percentage of avalanche fatalities (15 victims; 47%) during the 2007-2018 period. CONCLUSIONS: Asphyxia continues to be the most prevalent killer in avalanche burial. Patterns of ongoing avalanche deaths continue to suggest that rapid recovery and techniques that prolong survival while buried may decrease fatality rates. Trauma is a significant factor in many avalanche fatalities. Education and technologies focused on reducing traumatic injuries such as improved education in techniques for avalanche risk avoidance and/or use of avalanche airbags may further decrease fatality rates. Snowmobilers represent an increasing percentage of Utah avalanche deaths and now make up the majority of victims; increased education targeting this demographic in the basics of avalanche rescue gear and avalanche rescue may also reduce fatalities.

Causes of Death Among Avalanche Fatalities in Colorado: A 21-Year Review.

INTRODUCTION: A better understanding of the nature of morbidity and mortality in avalanche accidents helps direct both rescue efforts as well as preventive strategies to reduce fatalities. METHODS: We reviewed all avalanche fatalities from the avalanche years beginning in 1994 to 2015 in the state of Colorado, United States, using the database maintained by the Colorado Avalanche Information Center. For each fatality, we obtained the coroner's official determination of cause of death, and autopsy records if one was performed. We used these records to determine cause of death. Injury severity scores (0-75 scale) were calculated for those victims who underwent autopsy. RESULTS: Mortality information was available for 110 fatalities occurring during the 21-year study period. Of these, 64 underwent autopsy. Asphyxia was the cause of death in 65% of fatalities (72/110). Trauma was the cause of death in 29% of the fatalities (32/110). Of these, the primary cause was multiple system trauma in 38% (12/32), head trauma in 31% (10/32), and spinal injuries in 19% (6/32). Of the victims who died of asphyxia and had autopsy, only 10% (4/42) also had significant trauma, defined as an injury severity score greater than 15. There were 6 fatalities from other causes, including hypothermia, drowning, and primary cardiac arrest. There was no correlation between trauma and mode of travel, avalanche type, or starting zone elevation. CONCLUSIONS: Asphyxia was the primary cause of death in avalanche fatalities in Colorado during our study period. The incidence of fatal trauma was 29% and did not correlate with user group demographics or avalanche characteristics.

Characteristics and outcome of patients with hypothermic out-of-hospital cardiac arrest: Experience from a European trauma center.

BACKGROUND: Aim of the study was to investigate patient characteristics, survival rates and neurological outcome among hypothermic patients with out-of-hospital cardiac arrest (OHCA) admitted to a trauma center. METHODS: A review of patients with OHCA and a core temperature ≤32°C admitted to a trauma center between 2004 and 2016. RESULTS: Ninety-six patients (mean temperature 25.8°C±3.9°C) were entered in the study, 37 (39%) of them after avalanche burial. 47% showed return of spontaneous circulation (ROSC) prior to hospital admission. Survival with Glasgow-Pittsburgh Cerebral Performance Category (CPC) scale 1 or 2 was achieved in 25% of all patients and was higher in non-avalanche than in avalanche cases (35.6% vs 8.1%, p=0.002). Witnessed cardiac arrest was the most powerful predictor of favourable neurological outcome (RR: 10.8; 95% Confidence Interval: 3.2-37.1; Wald: 14.3; p<0.001), whereas ROSC prior to admission and body core temperature were not associated with survival with favourable neurological outcome. Cerebral CT scan pathology within 12h of admission increased the risk for unfavourable neurological outcome 11.7 fold (RR: 11.7; 95% CI: 3.1-47.5; p<0.001). Favourable neurological outcome was associated lower S 100-binding protein (0.69±0.5µg/l vs 5.8±4.9µg/l, p 0.002) and neuron-specific enolase (34.7±14.2µg/l vs 88.4±42.7µg/l, p 0.004) concentrations on intensive care unit (ICU) admission. CONCLUSIONS: Survival with favourable neurological outcome was found in about a third of all hypothermic non-avalanche patients with OHCA admitted to a trauma center.

Prehospital management and outcome of avalanche patients with out-of-hospital cardiac arrest: a retrospective study in Tyrol, Austria.

AIM: The aim of this study is to describe the prehospital management and outcome of avalanche patients with out-of-hospital cardiac arrest in Tyrol, Austria, for the first time since the introduction of international guidelines in 1996. PATIENTS AND METHODS: This study involved a retrospective analysis of all avalanche accidents involving out-of-hospital cardiac arrest between 1996 and 2009 in Tyrol, Austria. RESULTS: A total of 170 completely buried avalanche patients were included. Twenty-eight victims were declared dead at the scene. Of 34 patients with short burial, cardiopulmonary resuscitation (CPR) was performed in 27 (79%); 15 of these patients (56%) were transported to hospital with ongoing CPR and four patients were rewarmed with extracorporeal circulation; no patient survived. Of 108 patients with long burial, 49 patients had patent or unknown airway status; CPR was performed in 25 of these patients (51%) and 14 patients (29%) were transported to hospital. Four patients were rewarmed, but only one patient with witnessed cardiac arrest survived. Since the introduction of guidelines in 1996, there has been a marginally significant increase in the rate of documenting airway assessment, but no change in documenting the duration of burial or CPR. CONCLUSION: CPR is continued to hospital admission in patients with short burial and asphyxial cardiac arrest, but withheld or terminated at the scene in patients with long burial and possible hypothermic cardiac arrest. Insufficient transfer of information from the accident site to the hospital may partially explain the poor outcome of avalanche victims with out-of-hospital cardiac arrest treated with emergency cardiac care.

Avalanche Accidents Causing Fatalities: Are They Any Different in the Summer?

Pasquier, Mathieu, Olivier Hugli, Alexandre Kottmann, and Frank Techel. Avalanche accidents causing fatalities: are they any different in the summer? High Alt Med Biol. 18:67-72, 2017. AIMS: This retrospective study investigated the epidemiology of summer avalanche accidents that occurred in Switzerland and caused at least one fatality between 1984 and 2014. Summer avalanche accidents were defined as those that occurred between June 1st and October 31st. RESULTS: Summer avalanches caused 21 (4%) of the 482 avalanches with at least one fatality occurring during the study period, and 40 (6%) of the 655 fatalities. The number of completely buried victims per avalanche and the proportion of complete burials among trapped people were lower in summer than in winter. Nevertheless, the mean number of fatalities per avalanche was higher in summer than in winter: 1.9 ± 1.2 (standard deviation; range 1-6) versus 1.3 ± 0.9 (range 1-7; p < 0.001). Trauma was the presumed cause of death in 94% (33 of 35) in summer avalanche accidents. Sixty-five percent of fully buried were found due to visual clues at the snow surface. CONCLUSIONS: Fatal summer avalanche accidents caused a higher mean number of fatalities per avalanche than winter avalanches, and those deaths resulted mostly from trauma. Rescue teams should anticipate managing polytrauma for victims in summer avalanche accidents rather than hypothermia or asphyxia; they should be trained in prehospital trauma life support and equipped accordingly to ensure efficient patient care.

Burial duration, depth and air pocket explain avalanche survival patterns in Austria and Switzerland.

AIM: To calculate the first Austrian avalanche survival curve and update a Swiss survival curve to explore survival patterns in the Alps. METHODS: Avalanche accidents occurring between 2005/06 and 2012/13 in Austria and Switzerland were collected. Completely buried victims (i.e. burial of the head and chest) in open terrain with known outcome (survived or not survived) were included in the analysis. Extrication and survival curves were calculated using the Turnbull algorithm, as in previous studies. RESULTS: 633 of the 796 completely buried victims were included (Austria n=333, Switzerland n=300). Overall survival was 56% (Austria 59%; Switzerland 52%; p=0.065). Time to extrication was shorter in Austria for victims buried ≤60min (p<0.001). The survival curves were similar and showed a rapid initial drop in survival probability and a second drop to 25-28% survival probability after burial duration of ca. 35min, where an inflection point exists and the curve levels off. In a logistic regression analysis, both duration of burial and burial depth had an independent effect on survival. Victims with an air pocket were more likely to survive, especially if buried >15min. CONCLUSION: The survival curves resembled those previously published and support the idea that underlying survival patterns are reproducible. The results are in accordance with current recommendations for management of avalanche victims and serve as a reminder that expedient companion rescue within a few minutes is critical for survival. An air pocket was shown to be a positive prognostic factor for survival.

Avalanche Fatalities in the United States: A Change in Demographics.

OBJECTIVE: To describe demographic patterns in avalanche fatalities in the United States during the past 6 decades according to geographic location and preavalanche activity. METHODS: The Colorado Avalanche Information Center currently manages the National Avalanche Accident Dataset. This dataset describes deidentified avalanche fatalities beginning in 1951. Covariates included age, sex, month, state of occurrence, and preavalanche activity. Both absolute and proportional avalanche fatalities were calculated by year and by each covariate. A linear regression model was used to trend the proportion of avalanche fatalities stratified by covariate. RESULTS: There were 925 recorded avalanche fatalities in the United States between 1951 and 2013. There were an average of 15 ± 11 fatalities/y (mean ± SD; range, 0 to 40 fatalities/y). The mean (+/- SD) age was 29 ± 6.6 years (range, 6-67 years), and 86% were men. Total avalanche fatalities have increased linearly (R(2) = 0.68). Despite the highest number of total deaths in Colorado (n = 253), the proportion of avalanche fatalities in Colorado decreased (-5% deaths/decade; P = .01). Snowmobilers are now the largest group among fatalities and accounted for 23% of deaths (n = 213). The proportion of snowmobile fatalities has increased (+7% deaths/decade; P < .01), as has the proportion of snowboarder fatalities (+2% deaths/decade; P < .01). CONCLUSIONS: Avalanche fatalities have increased. This is most likely related to an overall rise in backcountry utilization. Fatalities have increased among snowmobilers and snowboarders. Despite a rise in backcountry utilization, avalanche fatalities in Colorado are decreasing. A strategy of focused training and education aimed toward at-risk groups could result in lower avalanche fatalities.

Outcome of avalanche victims with out-of-hospital cardiac arrest.

STUDY BACKGROUND: Previous studies focused on the outcome of avalanche victims with out-of-hospital cardiac arrest (OHCA) after long duration of burial (>35min); the outcome of victims with short duration (≤35min) remains obscure. AIM OF THE STUDY: To investigate outcome of avalanche victims with OHCA. METHODS: Retrospective analysis of avalanche victims with OHCA between 2008 and 2013 in the Tyrolean Alps. RESULTS: 55 avalanche victims were identified, 32 of whom were declared dead after extrication without cardiopulmonary resuscitation (CPR), all with long duration of burial. In the remaining 23 CPR was initiated at scene; three were partially and 20 completely buried, nine of whom suffered short and 11 long duration of burial. All nine victims with short duration of burial underwent restoration of spontaneous circulation (ROSC) at scene, four of them after bystander CPR, five after advanced life support by the emergency physician. Two patients with ROSC after short duration of burial and bystander CPR survived to hospital discharge with cerebral performance category 1. None of the 11 victims with long duration of burial survived to hospital discharge, although six were transported to hospital with ongoing CPR and three were supported with extracorporeal circulation. CONCLUSIONS: In this case series survival with favourable neurological outcome was observed in avalanche victims with short duration of burial only if bystander CPR was immediately performed and ROSC achieved. Strategies for reducing avalanche mortality should focus on prompt extrication from the snow and immediate bystander CPR by uninjured companions.

Effects of experience and commercialisation on survival in Himalayan mountaineering: retrospective cohort study.

OBJECTIVES: To determine whether previous Himalayan experience is associated with a decreased risk of climbing death, and whether mountaineers participating in commercial expeditions differ in their risk of death relative to those participating in traditional climbs. DESIGN: Retrospective cohort study. SETTING: Expeditions in the Nepalese Himalayan peaks, from 1 January 1970 to the spring climbing season in 2010. PARTICIPANTS: 23,995 non-porters venturing above base camp on 39,038 climbs, 23,295 on 8000 m peaks. OUTCOME: Death. RESULTS: After controlling for use of standard route, peak, age, season, sex, summit success, and year of expedition, increased Himalayan experience was not associated with a change in the odds of death (odds ratio 1.00, 95% confidence interval 0.96 to 1.05, P = 0.904). Participation in a commercial climb was associated with a 37% lower odds of death relative to a traditional venture, although not significantly (0.63, 0.37 to 1.09, P = 0.100). Choice of peak was clearly associated with altered odds of death (omnibus P<0.001); year of expedition was associated with a significant trend toward reduced odds of death (0.98, 0.96 to 0.99, P = 0.011). CONCLUSIONS: No net survival benefit is associated with increased Himalayan experience or participation in a traditional (versus commercial) venture. The incremental decrease in risk associated with calendar year suggests that cumulative, collective knowledge and general innovation are more important than individual experience in improving the odds of survival.

Parental mental health after the accidental death of a son during military service: 23-year follow-up study.

We prospectively studied parental mental health after suddenly losing a son in a military training accident. Parents (N = 32) were interviewed at 1, 2 and 23 years after the death of their son. The General Health Questionnaire and Expanded Texas Inventory of Grief were self-reported at 1, 2, 5, and 23 years; the Inventory of Complicated Grief was self-reported at 23 years. We observed a high prevalence of psychiatric disorders at 1- and 2-year follow-ups (57% and 45%, respectively), particularly major depression (43% and 31%, respectively). Only one mental disorder was diagnosed at the 23-year follow-up. Grief and psychological distress were highest at 1- and 2-year follow-ups. Spouses exhibited a high concordance of psychological distress. Mothers reported more intense grief reactions than did fathers. The loss of a son during military service may have a substantial impact on parental mental health particularly during the first 2 years after death. Spouses' grief can be interrelated and may contribute to their psychological distress.