Falk et al analyzed survival data from avalanche victims in Switzerland following burial in an avalanche. This can help identify ways to improve a person's chances of survival. The authors are from Austria and Italy.
Factors associated with survival:
(1) time to extraction
(2) existence of an air pocket
(3) traumatic injury
The rate of survival correlates with the time to extraction in the noninjured victim. The shortest extraction time is for someone superficially buried with uninjured colleagues nearby. If the person is deeply buried or if a rescue team is required, then extraction times will be much higher.
|
Time Buried in Minutes |
Survival |
|
0 |
100% |
|
15 |
92% |
|
35 |
30% |
|
90 |
27% |
|
120 |
20% |
|
>= 130 |
3% |
|
Time Buried in Minutes |
Equation for Percent Survival (from 0 to 100) |
|
0 to 15 |
(-0.533 * (minutes buried)) + 100 |
|
15 to 35 |
(-3.1 * (minutes buried)) + 138.5 |
|
35 to 90 |
(-0.0545 * (minutes buried)) + 31.909 |
|
90 to 120 |
(-0.233 * (minutes buried)) + 48 |
|
120 to 130 |
(-1.7 * (minutes buried)) + 224 |
The depth of burial correlates with the time to survival, since it takes longer to locate and extricate a person more deeply buried. In addition, this affects the type of air pocket that may be about the victim.
Effect of air pocket:
(1) A person without an air pocket have a high rate of death soon after burial (associated with the rapid fall-off in survival from 15 to 35 minutes).
(2) A person with a closed air pocket (not open to the outside) tend to survive 90 to 130 minutes.
(3) The longest survivals are associated with an open air pocket to the outside.
Specialty: Emergency Medicine, Critical Care
