I have seen steering columns fail explosively several time when being pulled with chains during training. This was mostly back in the 1970's and early 1980's and resulted from using spreaders to pull the column. This was a big enough problem that the state rescue program in Tennessee stopped teaching the technique during the 1980's. We did teach an alternate that included a double-X chain wrap under the tilt knuckle, and pulling the column ONLY with a come-along for less force and more control, but that procedure took so much time that it was quicker to just roll the dash.
Let's compare - the door has to come off either way. You can take the time to maneuver the chain around the column, the patient's legs - which may be broken and bleeding - find an anchor point under the front end, etc, etc, and this takes time. With hydraulics, you make one cut through the A-post above the dash, make a relief cut in the A-post between the top and bottom hinges, and roll the dash up. We trained people to do this part of the extrication in under 3 minutes. Preconnected multi-tool hydraulic systems eliminate most of the set-up time.
I used to have a minimalist approach to extrication, but what I found through extricating a lot of patients is that the more room you have, the safer it is for the patient. If you can take the same amount of time and make a big hole, why use the same amount of time and effort to make a small one.
If you look at an 0ver-the-hood chain technique from the side, the chain is roughly in the shape of a C. If the front of the car is severely damaged, then the C can actually compress during the initial pull. Picture lots of frontal intrusion. The engine and transmission are in a hydroformed safety cradle, which is shoved down and under the floor pan in the crash. All that's left to support the chain evolution is some severely torn-up and weakened sheet metal. You stress this metal together. As the chain pulls down the front of the hood/intrusion zone, it compresses the C. If the patient's legs are shoved up under the dash - which is common in frontal collisions - then the initial compression can actually pin the patient worse and definately can cause additional injury or make the initial injury more severe.
Using rams, jacks, or the spreader lift techniques lift the wreckage away from the patient with zero chance of compression, unlike pulling techniques. See my discussion on the Rule of Opposites for some of my rationale for this.
One other thing - lots of unibody cars don't have good places to hook chains under the front end any more. It can be a time-consuming and frustrating task just to locate an adequate place to hook the chain. Hooking the chain to another vehicle or heavy object isn't a good option, either, as you'll just drag the wrecked car/entrapped patient toward the anchor point.
I would like to see your tools cut some of the new steering columns out there. Too much time on something that probably wont be possible without comprimising the patient. Faster and safer to do a dash roll.
Never say never. There are times when significant dash displacment puts the steering wheel right in the patients face blocking their airway, or to there chest making patient removal difficult.
Like any other extrication technique, you need to expose the entire steering column and if you can remove the plastic on the dash do this as well. There is generally a nylon type ball connecting the steering wheel to the steering column. Make the cut here and you just gained 12 to 14 inches of space to work around. obviously make sure the airbags have deployed before you do tearing apart the dash.
If that's the case, then do a dash lift with the spreaders instead of rolling it with rams.
That will move the steering wheel out of the patient's way, create more room than any steering column attack ever could, avoid cutting in close proximity to the patient, and avoid the need to attack the steering column regardless of the deployment status of the driver's air bag.
With some of the metals used in steering columns today, the columns are becoming more difficult to cut.
We tried it as a last ditch effort in January in a blizzard on a Montana Van. The victim had already died and our primary set of jaws weren't working because it was so cold the hydraulics froze. We got things going again but our blades snapped clean off. Thank the good Lord we caused no harm to the victim.We were also thankful that we had our older original set to use while the new ones were repaired.
I have never seen a set of cutters not go through a steering column. If I were to speculate (as I wasn't there) I think the problem you may have been: 1. Becasue of the cold you had a lack of power to the tool. 2. That lack of power caused the tool torque and that is what broke the blades. 3. The cold could have made the metal in the cutters a slightly brittle thus weaker.
We have cut a few in training only. I've cut the spokes in a couple of extreme cases. Otherwise, the standard dash roll, usually is more than sufficient. Pulling the steering column? I think I did that once or twice 20 years ago. But there may be at some point, a need to do any and all depending on the circumstances of the crash, and sometimes old school is good to know.
There seems to be a lot of discussion about lifting the dash. To lift a dash you have to have room. Whether it be through a dash roll or using a spreader inside the vehicle or out. When a unibody car is in a frontal collision it has a tendancy to raise up in the fron and the back leaving the vehicle in a U shape. This can make a dash lift difficult as the spreaders won't fit in to do the lift, or the lift can't be made high enough to solve the problem. You won't always be able to lift the dash in a timely manner. All I am presenting is a tool to put in the tool box. I am certainly not saying cut every steering column that you come across.
I am not one to argue with what ifs. But in auto ex, you have to be prepared for the what if. What if you can't get a speader in place? What is the dash won't move? One of the basic rules of extrication is that for every action there is an equal reaction. To lift the dash, to roll the dash, it all has to be able to be displaced. That is not always the case. There are also other variables that need to be considered. Patient injury being the most important.
Another one I like is put the vic in a KED and cut the seat back off. The patient can then lay down and then they are out of the way as well. Of course, this is lower extremity injury dependant.
I have been on multiple extrications that would blow your mind the amount of damage to these vehicles. Many high-speed headons. When you're 15 minutes into the operations and the trauma surgeon (med control) shows up and says, you have 15 minutes to get themout or I'm cutting their legs off, you have to open the toolbox and pull somthing out.
There is one option that doesn't need ANY room inside the car to lift the dash with spreaders.
Pop the door, relief cut the A-post in two places, and lift the dash from the bottom relief cut.
You never need to put a tool inside the car to do that dash lift. The dash will displace, even if it has a reinforced lateral dash reinforcement bar or significant crumple damage. All you need is a few seconds to make the relief cuts. If you have a dash that won't displace, chances are that you either didn't make any relief cuts or that you didn't make them in the right places.
Then there's the old school dash lift where you simply turn the spreaders sideways and lift the dash. As long as you strip the purchase point to bare metal, you can simply crunch the dash out of the way. Once again, moving the dash will a) move the steering column with it and b) create a lot more room for disentanglement than simply cutting the steering column.
Cutting the seat back away is fine...if the patient's legs are not pinned under the dash. If the legs are pinned, freeing the patient's torso and pelvis may be part of the extrication, but it won't finish the job.
I've spent over three decades living "what if". What if has not yet required cutting a steering column with the driver pinned by it or immediately next to it. There's simply too much risk of explosive column failure causing further injury to the patient. That's not saying "NEVER", it's saying that it's almost impossible for cutting the steering column to pass a basic risk-benefit evaluation. There are just too many other techniques that are better, safer, faster, and don't require a trauma surgeon at the scene, let alone a field amputation.
Or...the column may simply have been made from a fortified metal alloy that was stronger than the cutter blades. Lack of power usually doesn't cause tool torque - it just causes the blades to stall and a secondary power unit stall.
If you lift the dash - even if it's at the North Pole in the dead of winter - there's no risk of the cutter blades breaking on the column, because you don't use them that way.