Depth through thoughtOUCC News 15th June 2011Volume 21, Number 5 |
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Editor: Andrew Morgan andrew.morgan@ed.ac.uk
Mike Hopley
Back in May, we had a rescue practice weekend in the Mendips, staying at the Wessex. We were privileged to have Gavin leading the "stretchers and hauling" session on Saturday, and Tony teaching us mid-rope rescue on Sunday.
First, I must put on my safety hat: do not attempt to teach yourself rescue just from this write-up; horrible accidents may happen if you do! This is a trip report, not a rescue instruction manual. (And practise in a safe environment. And be kind to animals and the elderly. And don't drink the Hunter's rocket-fuel scrumpy unawares, before blundering back without a head-torch. And for God's sake, think of the children.)
On Saturday morning, Gavin and Oliwia set off first to GB, giving them time to concoct interesting ways for Oliwia to injure herself. Gavin prepared a cunning twist: two casualties! Oliwia was obviously hurt and making some noise; as I arrived, most of the attention was on her. We found Gavin lying silent on the other side of the chamber. We faffed about for a short while, trying to work out what information had already been discovered, and who should be taking what role. The clock was ticking. We agreed that I should take charge of the first-aid, which I did ? and promptly cocked up.
I tried to establish whether Gavin was breathing (anyone spotted my mistake yet?). There were no signs of breathing (look, listen, feel). As he was lying on his front, I then got help to roll him over (the "log roll"). Rather than start mouth-to-mouth right away, I asked the casualty how intimate he wanted this role-playing to get, at which point he made a miraculous, temporary recovery and suggested something better:
Airway. Yes: in ABC, A comes before B. This is as basic as it gets, but I'd forgotten it in the heat of the moment. I've had lots of first-aid training, including some "advanced" stuff, but it's all from years ago; these skills really do fade over time. Establishing an open airway had him breathing again ? but in a real emergency, my delay could have been fatal.
(So when Jamie begs you to join a first-aid course before expedition, do try. It'll make him so very, very happy.)
Gavin heroically ignored his suspected spinal injuries so he could help us with Oliwia. She had broken her femur, and so was probably bleeding to death; but since we were already there, we had a go at rescuing her anyway. Straightening her leg reduced the muscle volume, making less space to bleed into. Nobody let me stick needles in her, despite knowing how much I enjoy it. We splinted her legs together with slings; and since she had also broken her collar bone, we splinted her arm to her side. She should have been treated as having spinal injuries, but the neck brace was pristine in its original packaging; Oliwia would just have to take her chances on permanent disability.
We fitted her into the stretcher and carried her back up the chamber. To keep it smooth, we passed her forwards rather than moving while carrying her: two cavers peeled off the back and joined at the front. When it got tighter, Vicky crawled with the stretcher on her back, with others helping from in front and behind.
Oliwia, needing a pee, soon recovered from her injuries. We then played around hauling Gavin out the entrance shaft, in his harness. It's difficult to learn hauling systems from words alone, so I'll aim this at people who already understand them and keep it brief:
We doubled the main hauling rope, attaching it to Gavin via a pulley, to give a 2-to-1 mechanical advantage. The free end was redirected horizontally through a pulley-jammer at the top. We then doubled an auxiliary rope through a pulley, attached a jammer to the pulley, and clipped this onto the main hauling rope. Pulling on the auxiliary rope gave a further 2-to-1 advantage, making a theoretical 4-to-1 in total (about 3-to-1 in reality). The jammer had to be reset frequently, by letting go the rope and sliding it back along.
We also had Gavin on an independent lifeline. A deviation was necessary near the bottom, set up with a releasable knot (a highwayman's hitch). We used another rope to help pull him sideways off the top of the shaft.
We then played around some more, replacing the pulley-jammers with Stops. Our Polish friends Miroslaw and Oliwia set up a fabulously complicated-looking system. As far as I could tell, they replaced our auxiliary hauling line with a Z-rig using a Stop, arranging things to create a belay station where the ropes could be managed more easily. Using Stops also made it easily releasable, and I suppose the whole system created a theoretical 6-to-1 advantage (good thing the anchors were strong!).
On Sunday Tony arrived and taught us mid-rope rescue - for free! This was an excellent session; I got to practise some things I've been meaning to try for ages. The Wessex SRT tower was perfect for our needs.
We started with easy scenarios. A caver is incapacitated while abseiling, and hanging on his descender. You want to reach him and lower him to the bottom of the pitch. It's better to arrive below the casualty, not above. This allows you to ensure a gentle landing, rather than just dumping him below you and abseiling onto his head. If you're above him, this means down-climbing on your ascenders and then passing him, as if he were a knot.
You attach your harness maillon to his, using a link of two locking carabiners. As a backup, you also clip your short cowstail to his maillon (with the gate facing you). Detaching your ascenders, you hang from him by the carabiner link. You then abseil down using his descender. It's all rather intimate, and I bet Vicky got some good photos.
Next we looked at passing a rebelay with the casualty. The trick is not to load your cowstail, because you will struggle to unload it! Instead, you use two descenders: attach your descender (and braking krab) next to his, on his harness maillon, thread the lower rope into it and lock it off; then abseil into the rebelay loop to unload the first descender and remove it from the rope; and finally unlock the second descender to carry on down.
One danger: if you let the rebelay loop come between you and the casualty, you will be stuck! This is easily done, and it's always worried me. How would I escape? Tony had the solution: cut the rebelay loop! Once you're untangled, tie the cut ends back together. Scary? Yes. Potentially life-saving? Yes.
Next we looked at a technique for helping an exhausted caver climb to the top of a pitch. You take the free end of the rope, where it exits the casualty's Croll, and feed it through his harness maillon. You climb up to the top of the pitch, taking this free end with you. You attach a spare jammer to the loaded rope, and attach a pulley to this jammer. You run the free end through this pulley.
You then prusik on the free end of the rope, while pulling up with your arms on the section of rope between the casualty and the pulley. His harness maillon is effectively acting as a second pulley, albeit a crude one; this gives you a theoretical 2-to-1 advantage. You'll definitely be able to help him make progress, and you may even be able to lift him on your own. Unless he's a fat bastard.
Finally, we looked at lowering a caver who is incapacitated and hanging on the rope by his ascenders. This has traditionally been a difficult manoeuvre, because you must unload his weight from the Croll. The older techniques involved brute force, counterbalancing your weight against his, or a 2-to-1 lift (i.e. refined brute force). Many cavers, including very capable and experienced cavers such as Fleur, had long ago decided that it was too difficult and dangerous; they would not take the risk of becoming a second casualty.
For our group, Sunday's practice changed all that. We looked at a newer technique that involves cutting the rope. It is surprisingly easy, but it sounds scary. Seeing it demonstrated took away the fear. By the end, everyone seemed fairly confident in performing this pick-off. I won't attempt to describe it properly here, as that would be long-winded and hard to follow. Here's an outline instead:
You take the the rope from below and tie a figure-eight loop in it. You bring this up, clip it to his jammer, and attach his descender below it (locked off). You detach him from his jammer, and cut the rope above his Croll. You have effectively "inverted" the lower part of the rope, which is being held up by his jammer: this jammer bridges the gap between the two halves of the rope. You're both hanging off a single jammer! Scary? Yes, until you get used to it. Unsafe? No: the jammer, being loaded, is impossible to detach.
You unlock his descender and abseil down. I've skipped some steps, but that's the gist of it. When you cut the rope, you also have a backup jammer attached higher up.
The great thing about this technique is that it requires no physical strength. It doesn't matter how light you are, or how heavy the casualty is. It works in just about any situation, including when there are rebelays below. And that was it. We didn't have time to try a Spanish pendulum (another hauling method), which was the fifth item on Tony's list. I would recommend trying this too if you get the chance; I find it works even better.
Miroslaw and Oliwia turned out to be frighteningly competent in all this rescue stuff. They told us that in Poland, caving is a "licensed" activity - much like scuba diving is over here. You need to get a qualification before you can go caving. Is that a good thing, or a nuisance? I don't know, but these Polish cavers certainly know their stuff.
Another useful idea: before getting underground, it's good to check out each other's kit (steady). You might be caving with someone from another country, or just someone as perverse as me who likes to dress up as a Frenchman and sometimes as a French American. Many of these rescue techniques involve using the casualty's SRT kit, so it helps to understand those weirdo setups. And who knows? You might even pick up some neat ideas among the deviancy!
I hope there will be more weekends like this in the future. The stretcher stuff is always good, but I don't recall any previous sessions on mid-rope rescue. Maybe we can start to pass on these skills within the club!
For those who are interested in learning more: Gavin maintains an excellent rescue guide, which is our main reference for carrying out rescues on expedition: http://users.comlab.ox.ac.uk/gavin.lowe/Caving/rescue_intro.html
The mid-rope rescue techniques that Tony taught us are described in the book Alpine Caving Techniques:
Note that the assisted prusiking technique in this book differs slightly from what Tony showed us, in that it uses the casualty's jammer instead of a spare one. I'd say both are safe, but I would prefer Tony's method if the spare kit was available. ...and for extra credit, the Spanish pendulum is on page 288. Oh come on, how can you resist a rescue technique that sounds like an acrobatic sex position?