Technological Advances in Avalanche Survival

Abstract

Over the last decade, a proliferation of interest has emerged in the area of avalanche survival, yielding both an improved understanding of the pathophysiology of death after avalanche burial and technological advances in the development of survival equipment. The dismal survival statistics born out of the modern era of winter recreation unmistakably reveal that elapsed time and depth of burial are the most critical variables of survival and the focus of newer survival devices on the market. Although blunt trauma may kill up to one third of avalanche victims, early asphyxiation is the predominant mechanism of death, and hypothermia is rare. A survival plateau or delay in asphyxiation may be seen in those buried in respiratory communication with an air pocket until a critical accumulation of CO2 or an ice lens develops. The newest survival devices available for adjunctive protection, along with a transceiver and shovel, are the artificial air pocket device (AvaLung), the avalanche air bag system (ABS), and the Avalanche Ball. The artificial air pocket prolongs adequate respiration during snow burial and may improve survival by delaying asphyxiation. The ABS, which forces the wearer to the surface of the avalanche debris by inverse segregation to help prevent burial, has been in use in Europe for the last 10 years with an impressive track record. Finally, the Avalanche Ball is a visual locator device in the form of a spring-loaded ball attached to a tether, which is released from a fanny pack by a rip cord. Despite the excitement surrounding these novel technologies, avalanche avoidance through knowledge and conservative judgment will always be the mainstay of avalanche survival, never to be replaced by any device.

Patterns of death among avalanche fatalities: a 21-year review

“…21 Variations between studies point to differences in geography, such as mountain topography and distances for rescue flights, as well as demographics, notably different activity types. 9,[21][22][23] Experts stress the importance of avalanche survival strategies such as trying to escape, discarding potential anchors such as skis and creating a breathing space around the chest and face. 24,25 However, any trauma suffered while caught in an avalanche may impair survival strategies and increase the risk of burial and asphyxia.…”

“…20,26 Our finding of a far greater risk of trauma than reported elsewhere, coupled with a low proportion of cases involving complete burial, should prompt critical analysis of the risk spectrum of each activity group in western Canada's mountain terrain. The results of such an analysis should be used to guide adoption of other devices such as inflatable airbags 8,22,31,32 and breathing implements. 21,23,33 In our study, 51% of victims received cardiopulmonary resuscitation, and 21% received prehospital advanced life support.…”

Analysis of Non Enemy Action Deaths in Counter Insurgency Operations through Mortuary Services

“…In one study, survival probability in completely buried victims in open areas (n=638) plummeted from 91% at 18 minutes after burial to 34% at 35 minutes and then remained fairly constant until a second drop after 90 minutes [18].This steep drop ("fatal kink") underlines the importance of efficient rescue procedure and survival devices. Apart from a transceiver and shovel, these devices include artificial air pocket device (AvaLung), the avalanche air bag system (ABS), and the avalanche ball [19]. The artificial air pocket provides respiration during snow burial while ABS forces the wearer to the surface of the avalanche debris by inverse segregation to help prevent burial.…”

“…The artificial air pocket provides respiration during snow burial while ABS forces the wearer to the surface of the avalanche debris by inverse segregation to help prevent burial. The Avalanche Ball is a visual locator device in the form of a spring-loaded ball attached to a tether, which is released from a fanny pack by a ripcord [19]. Motorola have tested one GPS based system that gives effective signal up to one meter depth of snow [20].…”

Wilderness medicine

“…[85,86] Technologic advances designed to mitigate the risk of avalanche-associated injury and death include exhaled air diversion devices, flotation devices, and transceivers. [87] The science of avalanche forecasting has improved; detailed reports are available online. [88] Despite these advances, North American avalanche fatalities continue their upward trend.…”