The last avalanche forecast for the 2023-2024 season posted on April 21st. Thank you to all who contributed to the avalanche center this season through observations, volunteer time, and/or financial contributions.
Whether you have had a course on avalanche awareness, a level I AIARE class or are an avalanche professional, have you ever thought about what to do after rescuing an avalanche victim? Many of us spend time practicing with our beacons and our rescue gear, but few people stop to think about what happens to an avalanche burial victim and just what you might have to do to save a life. It is, of course, better to never be in an avalanche - but despite training, expertise and resources like the Sierra Avalanche Center, it occasionally happens.
Most avalanche course curricula appropriately focus on rescue. The importance of speed and skill with your beacon, probe and shovel cannot be overstated. These skills are not the focus of this article and should be practiced and mastered. As minutes go by, the chance of surviving an avalanche burial decreases minute by minute. Speed is essential.
There have been many studies looking at avalanche burial fatalities and the majority (75% or more) of fatalities are a result of asphyxiation. Depending on the study, between 5-25% of avalanche fatalities are the result of trauma. Less than 1% of fatalities are from hypothermia. There is not much we can do for trauma in the backcountry. The only hope here is rapid extrication to a trauma center.
Death from asphyxiation is time dependent. Simply put, the longer you are buried, the more likely you will die. The American Avalanche Association (AAA) published a graph that states chances of survival are 92% if you are extricated within 15 minutes. And chances go down to 37% after 35 minutes of burial time. To put this into perspective, the chances of death go up about 3% per minute after 15 minutes of burial time. Speed is essential.
The bad news is, the data published by the AAA is optimistic. You have even less time than that. A study published in Canada shows the probability of survival to be 86% after 10 minutes of burial and a decrease to less that 10% after 35 minutes. Speed is essential.
Care of the Avalanche Patient
Once you have made sure the scene is safe and located the victim, the priority is accessing and exposing the airway – rapidly. What you do next largely depends on the condition of your patient.
Awake/responsive patient?
Make sure the airway is clear, make sure they are breathing adequately and assess them for other injuries. Prevent as much heat loss as possible by getting them off the snow and onto a pack and put warm clothes on. Take a common sense approach here. Serous injury? Unable to self evacuate? There are countless scenarios here and we cannot discuss them all. Consider severity of injury, your location, the weather, the skill of your crew, time of day and the gear you have and make a reasonable choice. Call for help early if you think you need it.
Unresponsive patient?
Airway - Expose the patient’s airway and assess for the presence or absence of snow in the airway. Clear any snow from the airway. Try to immobilize the cervical spine (neck) here if possible. There is a significant chance for trauma in these patients. If the airway is not open, open the airway with jaw thrust (https://www.youtube.com/watch?v=r3ckgEQEE_o).
Breathing - Assess for breathing by watching your patient or put your hands on their chest. Put your hands in the patient’s arm pits (thumbs up) and squeeze a bit, you should feel the chest expand with each breath. Respiratory rate should be around 10-12 times a minute, or one breath every 5-6 seconds. Make sure to move the snow away from the patient’s chest if they remain buried. Densely packed snow may inhibit expansion of the chest wall.
If an unresponsive patient is not breathing, breathing too slowly or breathing very shallow, they need rescue breaths. Rescue breaths can be done by mouth-to-mouth, but I would not advise mouth-to-mouth. Rescue breaths are best given by a commercially available CPR mask. These are cheap, effective and provide the rescuer with some degree of personal protection. I carry a NuMask (no financial interest). The grim reality is, an avalanche victim will likely be unresponsive and may need some rescue breaths.
Circulation - Along with airway and breathing, you must check for a pulse. Specifically, a carotid pulse - (put your index and middle fingers on your neck just below the angle of your jaw and find your own if you are not familiar). A normal heart rate is 60 to 100 beats per minute. If the heart rate is slow (less than 40), cardiac arrest may be imminent without providing rescue breaths. If the patient has a pulse you should not have to provide rescue breathing for long. Patients typically regain the ability to breath adequately on their own – if they are free from trauma. In this case, prevent additional heat loss and call for help.
No pulse? Start CPR. 100-120 beats per minute. In the case of avalanche victims, it is always ABC-CPR (Airway, Breathing, Circulation). If you have taken a CPR class recently you have learned to do CAB-CPR or maybe you have learned about “compression only CPR” – these are not appropriate for avalanche victims (2010 American Heart Association Guideline for CPR).
For one-rescuer CPR the ratio of compressions to rescue breaths is 30:2. For two or more rescuers the ratio of compressions is 15:2.
When do you stop doing compressions? Ideally when you transfer the patient care to emergency medical service providers (EMS) – this may not always be possible. Knowing the burial time is key.
Short Burial Time
For burial time less than 1 hour, efforts should be stopped if you’re not successful in getting a pulse after 20 minutes and there is no reasonable transfer to EMS providers. Termination of efforts by EMS crews is determined by their existing protocols.
Long Burial Time
For burial times that exceed 1 hour the presence or absence of snow in the airway becomes crucial – this should be identified during your initial airway assessment. For the avalanche victim with snow in the airway and a burial time that exceeds an hour – stop. This person is dead.
For burial time greater than 1 hour and NO snow in the airway, you must continue your efforts. In these cases, hypothermia may be playing a role in their cardiac arrest. The avalanche victim is not dead until they are warm and dead. There are several cases of avalanche victims surviving prolonged burials in these circumstances. These patients should be evacuated.
The keys to success are to decrease burial time, provide early and adequate rescue breaths, prevent hypothermia and call for help early. For more information on managing trauma in the backcountry consider taking a wilderness first responder course. Or if you are a medical provider and want to learn to apply your medical training to the backcountry, consider a course from Tahoe Wilderness Medicine, LLC.
Article courtesy of Tahoe Wilderness Medicine