2016-02-02 regular training/Cold Weather Injuries lesson plan

00:00

3 min

Introduce topic title

Introduce Instructor

Present Objectives

00:03

Scenario Introduction

It's mid February of what's been a snowy winter.

PCSAR gets a call at 01:00 from the local RCMP. A couple from Calgary, Leonard and Sally Hughes, in their mid-twenties are missing. They were expected back at a Beaver Mines bed and breakfast last evening after a day of cross-country skiing. Their vehicle has been found at the Syncline Cross Country Trails parking lot.

The conditions yesterday was -5 C, with heavy snow in the afternoon. Tonight it's -25 C, with 10 km/hr wind. Tomorrow during the day it's expected to be -20 with 40 km/hr wind.

Multiple ski trails leave the parking lot, partially obscured by new snow.

Addressing Hazards

Pick a student to act a part of the overhead team. To answer questions in that role. Involve the group in discussing answers.

You've been asked to help as part of the Incident Management Team. It's 04:00 and while 2 snowmobile teams are sweeping the trails, the Incident Commander is starting to think about calling for more searchers for dawn 07:30. More snowmobiles but also ground searchers on cross-country skis and snowshoes to search between trails and the unofficial trails that are too tight for snowmobiles.

You are asked to think about and identify all the hazards that will need to be addressed in the morning.

Among others, student should identify risk of cold-related injuries, in particular hypothermia.

What can the overhead team do to address the risk of cold-related injuries to searchers? To the subject?

Among others, should suggest

• describe risk and weather in call-out and in team briefings
• have searchers checked for appropriate clothing (by Team Leaders?)
• make sure SAR's cold-weather equipment arrives on scene
• call for SAR's briefing trailer as a searcher rewarming shelter
• develop a plan to treat and evacuate searcher injuries

Group Equipment

Ask same student, fill in with group discussion

What group equipment does PCSAR have for cold-weather injuries?

• 2 hypothermia kits (1 in firehall cabinet, 1 in the pack stretcher in the equipment trailer)
• stretcher and packaging for snowmobile sleigh (mounted in ATV trailer)
• briefing trailer

Group Equipment Hands-on

Have the students bring the hypothermia kits and the stretcher to the classroom. This is good practice for them locating the equipment. If necessary have discussion of where equipment is stored, how to access.

When equipment arrives, open up and examine.

• At least one of the hypothermia kits is expired, open up and examine
  • Take photos

Safety Check

Pick a student to act as a Team Leader

You're assigned as a Team Leader of a group of 4, none of who you know. Your initial assignment is Type 2 search of a segment of rolling hills, wind-exposed hilltops and heavily wooded areas. You figure it will take at least 4 hours to complete.

You know you should do a safety check of your team. What will you look for?

Expand to an open discussion. There are many possible answers here, but direct towards discussion of thermal management.

• Fitness level of searcher
• Clothing
  • 3 layers: wicking, thermal, wind-protection
  • ability to adjust, remove/add layers, open up, pit zips
• Food
  • high energy
  • plenty of water
  • avoid caffeine
  • avoid nicotine

Avoiding Sweat

Pick a couple of students

You've both been assigned as part of a team of 4. It's cold at the Search Base while you're waiting to get going. What would you be wearing?

Your first assignment is a segment close to the Search Base. But first you have to go up a steep hill to get to it. The Team Leader and his friend lead the way, climbing rapidly. You two are starting to sweat. What's wrong with that?

• wet clothes don't insulate well
• moisture cools as it evaporates
• loss of energy

What do you do?

Good answers

• open up clothing
• take off touque, gloves, mitts
• call for a slower pace
• call a stop
• change layers

Treating Mild Hypothermia

Pick 4 students

You are a team of 4 that's been assigned to search an unofficial trail higher on the mountain. You are shuttled up to the trail on snowmobile, but they can't go further because of the large number of partially fallen trees.

Your team follows the trail for about an hour and then stops for break and to call-in. Unfortunately there's no radio coverage here, so the Team Leader (#1) and the radio person (#2) climb to a higher point, still within sight of the rest of the team.

When the two get back, the two that stayed are shivering hard. One of them (#3) wants to get going to warm up. The other (#4) insists there's nothing wrong and seems a little angry.

Have two of the students mime this.

How serious is this? What should you do?

Have group role play. If they don't come up with the "best" answer, describe consequences, give them a little bit more information.

They both have extra clothes they could put on.

If decide to travel:

• After about 5 minutes #4 starts stumbling, taking off his jacket. He falls, is confused and is no longer shivering.
• Stop at this point.
• Does anyone know why s/he got worse?
• Discuss rewarming shock
  • cold blood from extremeties enters core and lowers core temperature causing severe hypothermia
• Reset the scenario

If they decide rewarm without checking level of shivering:

• Discuss how they rewarm (see below for best answer)
• Discuss delay and option warming up by moving (exercise)

As necessary, introduce test to check for risk of rewarming shock

• Can the person will themselves to momentarily stop shivering

Best answer:

• Because they are shivering they are in "mild hypothermia", not severe
• Should ask them to each try to momentarily stop shivering. If they can, they are not at risk of rewarming shock.
  • One can't stop shivering.
• Encourage that person to continue shivering.
• Avoid strenuous exercise for that person.
• Address sources of heat loss:
  • check for and consider removing soaked inner clothing (address conduction)
  • add toque, layers of clothing (address radiation)
  • get out of wind, breeze (address convection)
  • dry (address evaporation)
• Improve heat generation
  • high energy food
  • water
• Apply external heat
  • fire
  • body-to-body (clothed)
  • hot drink
• Once recovered, consider returning to base due to muscle exhaustion (shivering) and energy loss

Severe Hypothermia - CPR

Pick another team of 4

Your team finds Sally Hughes lying at the side of a clearing. She does not appear to be breathing. Her body is cold.

You radio the Command Post and are told that a helicopter will be there in 15 minutes.

Another team radios you to start CPR. Should you?

Best answer:

• Check first for a pulse.
• If there is a pulse don't apply CPR. Rough handling can cause a heart attack.
• Check for up to 3 minutes for a pulse. Hypothermic casualties have much slower and harder to find pulses.
• Apply CPR if it can be sustained until help arrives.

Some hypothermic people have survived as long as hour without any effective circulation and recovered without brain damage.

Severe Hypothermia - Treatment

Good news:

You find that Sally has a very weak pulse and is breathing very slowly.

Bad news:

The helicopter has engine problems and isn't coming.

What can you do with the equipment in your ready packs?

Have 4 students play out with the mannequin.

Best answer

• treat gently to avoid ventricular fibrilation
• reduce heat loss
• apply external heat, as many methods as practical
  • heated environment
  • hot water bottles, especially to neck, armpits, chest, abdomin, groin

Severe Hypothermia - Treatment 2

Good News:

The snowmobile team has cut its way to your location. You now have the group cold weather first aid equipment and more helpers.

All students to be involved. Assign an overall leader.

What can be done with the new equipment?

Open one of the expired hypothermia kits and test for reheating function

Severe Hypothermia - Transport

Bad News:

Best advice says transporting a severe hypothermic patient by sleigh or litter party will almost certainly cause ventricular fibrilation. It's almost dark and a new helicopter won't be there until morning. What are you going to do?

Best answer:

• Continue to rewarm until out of severe hypothermia or helicopter available

Frost Bite

Pick another student

You are on the team that finds Leonard Hughes. He is stumbling slowly along an unofficial trail. He seems clear headed and thankful to be found. He's not shivering but complains of his feet being frozen, as are the fingers of his left hand and his ears.

A snowmobile can be here to help carry him out in about 2 hours, after clearing some trail. It will be about another hour back to the Search Base where an ambulance will be available.

You have the most first aid training on the team. How will you handle his injuries?

Best answer

• Keep him warm
• Do not deliberately thaw frozen areas
• Loosen constrictions (boots) to frozen areas
• Do not remove boots
• Do not separate frozen fingers but place gauze between to prevent further maceration
• Prevent any thawed areas from refreezing

If thawing, do so rapidly with water just above body temperature (38-42 C).