Implications of suspension trauma for climbing self-rescue

I never said that suspension trauma could be the cause of the loss of consciousness in a typical climbing situation, but I don't believe that it's trivial either. I think that it can rapidly make a bad situation a lot worse.

The message from both your posts is loud and clear: the leader being unconscious after a fall means that there are much more urgent and important things to worry about than this suspension trauma that’s not really a trauma at all and that happens only very rarely. The position you describe follows logically from that statement: once you’ve taken care of keeping head and back aligned with a C-collar fashioned out of a SAM splint and some clothing, tilting the victim backwards would just be asking for trouble with the issue of holding the head in suspension; and, of course, worrying about the legs would be pointless. However, with everything I've read about suspension trauma, I remain convinced that it's a serious issue that should not be dismissed out of hand from the rescue plan.

If it turns out that getting the victim into a good position can buy enough time in which to complete a safe lowering, I could definitely go for fashioning a C-collar and placing it on the victim first thing upon reaching him, before any other positioning steps. However, if it could not and if suspension trauma can lead to catastrophic outcomes in people who are sensitive to it more rapidly than I first thought, then I’ll worry about the C-collar after I've quickly lowered the victim.

jktinst, thanks for the original post. Very thought provoking for me. This is the first time I have seen an attempt at designing a system to assist an injured climber with a "suspended position of recovery". It would seem to me that, with myriad and unforeseen circumstances possible, some exploration into this might be warranted. Also, in-line stabilization is worth considering but is not compulsory.

I've been yelling about the possibility of suspension trauma for years, mostly to deaf ears.

I think the biggest problem is that in a difficult rescue of a fallen leader, it is likely to take the average not especially efficient climber so long to reach the leader that suspension trauma will be a significant possibility if the leader isn't able to move around. Indeed, the protocols in the self-rescue books used to be so ridiculously long that I wondered if suspension trauma wouldn't be guaranteed.

Now Fasulo, in his latest edition, has finally recognized the issue, and makes more of a point about trying to get the leader out of of a hanging position. I think this needs emphasis; if at all possible get the leader's weight off the rope by lowering. It is true that this could risk making other injuries worse and maybe even fatal, but leaving a badly injured leader hanging for 15 to 30 minutes or more while the belay is escaped and the rope is ascended seems to make it pretty likely it will be a recovery not a rescue.

As for rigging all those funky inverted hanging positions for an unconscious person, good luck. Personally, I wouldn't try it. If the victim can be reached relatively quickly before suspension trauma is likely to have begun, then wouldn't it make more sense to elevate the legs for, say, five minutes or so to undo the beginnings of any pooling and get blood pressure more nearly normal and then, with suspension trauma postponed, lower them vertically?

Read a little into suspension trauma, concern is the blood pooling in the legs and starving the heart of blood, causing death.

Yes it is a concern, but let me throw in there a few things, and clarify a few already stated.

This entire post is about dealing with an unresponsive leader. Why is he unresponsive? Was he hang dogging and pass out? Or did he fall and hit his noggin? Did rock fall strike his melon?

All three of those scenarios are very emergent situations, why? The leader is unconscious. What makes it emergent? Airway. Tongue rolls back and obstructs the airway. Without oxygen to come into the lungs and carried by the blood for dispersion throughout the cells of the body, doesn't really matter if patient has suspension trauma or not, he will be dead.

This is where you need to ask, what is quicker to open the airway and get patient where you can keep that airway patent, climb up to him? Or let him down? This is where it just depends on situation, more in likely it will be to lower him to your belay ledge.

So airway is dealt with, now is the time to ask why is he unconscious again? If he had been just hanging around and went all syncope on you, then by all means, concentrate a lot of effort on dealing with the suspension trauma, Ideal situation would be a belay ledge where patient could be rested on and pressure taken off harness and legs. Compartment and crush syndrome are still a worry here, if the blood has pooled in the legs enough that the pressure is so great that blood can't return to the heart, it becomes compartment syndrome, in other words the blood has become acidotic, or stagnant. Lifting the legs would be bad here, the circulation needs to return slowly so that sodium bicarbonate created by the pancreas can compensate and return the ph balance of the blood to normal ranges. I stated in an earlier reply that as EMS, we would administered Sodium Bicarb, that would be because the pancreas can't keep up. Unless the leader is extremely lucky, this won't be an option, so slowly regaining circulation will be the key.

Now what if he is out because of trauma? Everyone has been focusing on head trauma, but what I'm about to say happens with all trauma. In all trauma, the body goes into shock. Many different kinds of shock, but to stay on topic, going to try and keep this simple, but this case would involve hypolvemic, neurologic, and septic shock. In all kinds of shock the body shunts blood to the major organs. This is part of an autonomic nervous system to keep us alive. By shunting the blood, I mean the body will vasoconstrict, or tighten down on vessels (veins, arteries, capillaries), almost like a tourniquet, so the blood supply remains more than adequate to perfuse the major organs needed for life. This starts at the fingers and toes and works towards the body core, shunting until bloodflow is maintained to the organs. This will raise the patients blood pressure significantly, and they will have an increased heart rate, so the pump will be working harder, pumping more blood, and respiratory rate will also increase to compensate for the increased blood flow, oxygen has to get in the blood, if blood goes faster, oxygen has to get into it faster. This star that the patient is in is known as compensated shock. With all this going on, one could see how it would be harder for suspension trauma to actually occur, not saying it can't, but the shock will make it harder for it to happen.

More than likely this is a head trauma. In head trauma, the pressure in the ICP (inter cranial space) increases by swelling of the brain, or bleeding in the brain. The cavity in which the brain sits is very tight, almost no extra space exists, and it's airtight, blood can't get out, so as a vessel bleeds, the blood pools, pressure increases. As ICP pressure increases, it will act as a tourniquet to other vessels bringing oxygenated blood to the brain, suffocating it. The brain being the motherboard of the body, it kicks the compensation and shunting into overdrive, protecting the brain, heart, and lungs the most. This is why head trauma patients typically have blood pressures that are through the roof, thus making suspension trauma even harder to actually happen.

Now with the head trauma, also come c-spine worry. If the spine has been fractured anywhere from C1 down to about L1, thats 19 vertebrae, there is a huge risk that the fractured bone will severe the spinal cord, and in between those before mentioned vertebrae, especially C1 through C7, it will stop all nerve signals to the major organs, without those signals to activate the muscles and organs, we die. The cord may not have been damaged in the actual trauma, but could very easily happen if proper c spine is not taken and maintained. The bones moving around during inadequate c spine can severe the cord. This is why c spine would be of higher priority than suspension trauma.

So patient is resting on a ledge, weight off leg loops, airway open, c spine is good, now what? Can you call for rescue? If so, just wait there if it is not compromising anything. More than likely however, you will need to get to the ground and get help. This is where you ask yourself, how is the safest, easiest, quickest way that is best for the patient. Every real world scenario will be different. In EMS/Fire we would be using a stokes and could lower the patient in a horizontal fashion, with the patient being fully immobilized. Sometimes, if the situation demanded it, we would lower feet first. Feet first is the way I would prefer if doing this by myself in this situation, without rescue gear. This does a couple of things, one, it keeps the spine inline, move the patient in long axis moves whenever spinal immobilization is done, and two, if the patient happens to strike something on the way down, they will strike it with their feet, not the more sensitive back area, or worse, the already injured head.

Right now the suspension trauma people are saying, "you can't lower feet first, it will make it worse." The compensated shock will take care of it, and more important, suspension trauma can be reversed with medications, a severed spinal cord can't. I am not saying to totally forget about suspension trauma, take rest on the way down, get that patient on another ledge, but don't lower in a fashion that compromised c spine or where the legs will be higher than the head, it will kill them. As I have mentioned before, the feet higher will rush acidotic blood to the heart, bad, and it will also increase the ICP even more, bad. Other things I have mentioned before is the floppy, unresponsive body. This is where a 180lb person becomes a 300lb water bed mattress, fancy rigs to lower will be very difficult to manage by yourself on the side of a rock, gravity in going down feet first will help immensely with keeping limbs close in and not flailing about and catching on stuff. The other thing with head traumas, is they can be "out of it", very altered mental status and very combative, or/and be having seizures, all of this easier to handle by using gravity to help by going feet down. Again, go feet down quick, get to the next rest ledge, get to the ground, the ground is the goal.

Once on the ground, it is a matter of getting rescue personnel there. Still don't want feet higher than head.

Another thing I forgot about head trauma, is they tend to vomit. If they are head down lower than body, they have a high possibility of aspirating the vomit into their lungs, which will turn into an infection and kill them. Aspirated vomit kill thousands every year, far far, like 1000x more than suspension trauma. One more reason to lower feet first, it makes the least possible situation for vomit to be aspirated.

Now if patient was hanging, got syncope, you lowered, no trauma, no c spine worry, then yes, your lowering idea would be suitable, but I have hung in harness while making routes a lot, usually get the "asleep" feeling in my legs, que to get moving them, and have never come close to passing out. I have also had patients do the stand too long and pass out, same theory as suspension trauma, and they will be out for a minute, but come right back around, the body is amazing at compensating, not saying that the whole suspension trauma unconsciousness thing couldn't happen without trauma, but think the odds are pretty high it won't.

Don't have much time right now but with all this talk of lowering the victim feet first, I'd just like to make sure that everyone is clear that the only time the victim should be lowered unaccompanied, if at all, should be during the first rushed lowering to that first desuspension spot (most likely the belay ledge or the ground but it could be an intermediate ledge) if it can be done relatively safely or if we've decided that lowering fastest and at all cost was the way to go. After this first rush to desuspension and emergency treatment, if the decision is made to keep going down rather than wait in situ for the rescue, the victim may be in an upright piggy-back on the rescuer's back or in a flatter (semi-fowler?) suspended position crosswise in front of him (we've already established that the feet should not be higher than the head) but, either way, the feet that should hit any obstacle first should the rescuer's, not the victim's.

Agreed, should lower together. Being horizontal or semi fowlers in front of you is going to do more damage than good without proper spinal immobilization however. We do lower that way all the time, but its with the proper equipment, like a stokes basket or SKED or the like. Piggy back could work, a reversed piggy back, so the patient and the rescuer are face to face, patients hands ties together and around rescuers neck, patients legs tied together around rescuer waist, would work better. We do that for rescue with ground ladders. Either way you do it, piggy back or in front, you are using your body as kind of a backboard, which is a lot better than horizontal or semi fowlers or trendelenburg without proper equipment.

It just seems that you are putting too much emphasis on suspension trauma. It is important, and needs to be kept in mind, but there are other priorities in the care of the patient. What I guess I am trying to get at is that you do need to take care of the suspension trauma, but not if it compromises the proper care of airway or spinal which takes priority if keeping the patient alive.

Your earlier point about the vasoconstriction reaction to trauma and shock and the possibility that it could counteract to some extent the effect of suspension trauma is quite interesting. However, as Mortimer and many of the authors he reviews say: victims who die from suspension trauma in the absence of other trauma die of shock. That is why Mortimer insists on calling it a trauma. This state of shock develops from the accumulation of blood in the legs and, in those cases, the vasoconstriction reaction was clearly not sufficient to counter that effect. It could be that other kinds of trauma might be more effective at triggering the vasoconstriction reaction or that it does get triggered in pure suspension trauma just as much and that without it, we would see many more deaths from suspension trauma than we do now. I have not seen any information about this.

Regarding the relative position of victim and rescuer, it would be very difficult to rappel with a victim wrapped around you at the front but the trickiest would be to contrive by yourself to end up with the victim’s legs wrapped around your mid-section and tied behind you so they stay out of your way during rappelling... It is not impossible but it would definitely not be KISS. This is why self-rescue manuals only talk about the piggy-backing option.

Although the victim will have a much better chance if an organized rescue can come and collect him from the first desuspension spot, let’s look at what it would mean to have to keep going down and to do so with the victim upright in a piggy-back position during subsequent rappelling. The main issue in this case is that the victim has to go from lying down unsuspended to being suspended and upright (and vice-versa at the next rappel ledge down and so on). Even dismissing suspension trauma as a concern for doing the next rappel upright, it seems to me that this manipulation is not going to be any good for the victim for some of the very reasons you cited previously.

If we’re concerned about his blood pressure and shock from other trauma, everything I’ve learned in first aid says that this change of position is going to be pretty bad for him, vasoconstriction or not. I also suspect that the manipulation is not going to be too good with regards to the victim’s neck and spine, even if we’ve managed to slap a makeshift C-collar on him, unless you have some other stabilization system. On the other hand, I don't necessarily disagree with your reasons for preferring a more upright position so it seems like another case of damned if you do, damned if you don't.

Perhaps some compromise position between semi-fowler and upright with a system that would make it possible to tilt the victim more upright or more horizontal depending on the symptoms observed? I keep coming back to the basic principle of the position1 system: the munter on the cord linking knees/feet with head/torso and clipped into the main suspension biner. This system allows this easy tilting back and forth. You just have to push/pull on both sides of the cord at the same time to shift it one way or the other and it stays there when you let go.

rgold wrote:... If the victim can be reached relatively quickly before suspension trauma is likely to have begun, then wouldn't it make more sense to elevate the legs for, say, five minutes or so to undo the beginnings of any pooling and get blood pressure more nearly normal and then, with suspension trauma postponed, lower them vertically?

If you’ve reached the victim and are planning on lifting his legs, you will need to install a chest sling and secure it to the rope first. After lifting/shaking the legs, you might as well take another minute to get the knees suspended (eg one sling to hold up each knee in the piggy-back counterbalanced rappelling). However, it’s still unclear whether the 5min. you will spend working on the chest sling and the victim's legs will do any more than pause the progression of the trauma for the same length of time, only to have it resume as soon as you stop and return your attention to the task of getting the victim down.

It wasn’t only the Querellou review that gave me doubts about the possibility of durably halting or reversing the progress of suspension trauma while remaining in suspension. The camptocamp discussion had a link to a documentary on the clinical tests done by Dr. Bariod (and reviewed by Querellou & Mortimer). The three volunteers were all in different positions in caving-type sit & chest harnesses (eg: with feet held elevated by the ascension stirrup but with head dangling back, or with a proper C-collar on but with legs dangling straight down). All 3 developed presyncopal symptoms and attempts to alleviate those by keeping the head propped up or the legs lifted up for the rest of the test effected only a very temporary reversal of the symptoms before they started progressing again.

Of course, since this study was on only 3 volunteers, it was not very representative. The Madsen study on a large number of volunteers, using a tilt table and bicycle seat instead of an alpine harness showed that and under-the-knee strop had a preventive effect on syncope development. This is what led Mortimer, Querellou and the HSE to recommend raising the legs of the victim upon reaching him but, from what I can gather from the abstract of the Madsen paper, the strop was installed from the start, not used to try and counteract an effect already well on its way. Anyway, you can see why this led me to look and ask for clarification as to whether lifting the legs would alleviate the trauma sufficiently to make the necessary time investment worthwhile in a climbing situation (as opposed to the faster caving scenario).

The skeptic in me says you just can't make it up to a leader in time to be effective in a true case of this problem. You can possibly make a difference in the secondary window, if you had to get up to them.

jktinst wrote:... but the trickiest would be to contrive by yourself to end up with the victim’s legs wrapped around your mid-section and tied behind you so they stay out of your way during rappelling...

Rereading this made me realize two things:

1) Wrapping the legs would not be all that tricky because they would not necessarily have to be tied together behind the rescuer's back to be kept out of the way, or lifted from their floppy dangling state only after positioning the victim and rescuer face-to-face. I suggested wrapping a sling around each knee for the piggy-back counterbalanced rappel and the same could be done in this case. Attaching these slings to the victim's rope just above his knot prior to positioning face-to-face would keep the legs on either side of the rescuer.

2) A much bigger issue is the fact that the angle of the victim’s body would be determined by the angle of the route. In the face-to-face configuration, the victim's rope and the tether connecting the rescuer to the rappel device would have to be sandwiched between the two and would be aligned with the rescuer's loaded rope and the rappel anchor. On a route that is vertical or less, the victim would be forced backwards, especially at the beginning or the rappel in all cases and all along the pitch in the case of a slab route. Only on overhanging pitches would the rescuer be able to keep the victim vertical without too much difficulty.

I don't know if there might be even bigger strikes against the face-to-face position but this second point would seem to provide ample reason by itself as to why the technique would not be recommended or used in climbing self-rescue. With the piggy-back, the rescuer can reasonably easily wrap the two bodies together. In addition, in this case, the angle of the victim’s body is determined solely by that of the rescuer who has a lot more control over his own angle than with the face-to-face.

Using the equivocation hitch as a self-rescue anchoring system that can be released from above?

This might have warranted a new thread but it is part of the same reflection on the options for bringing down as fast and as safely as possible an unconscious leader in situations when lowering him unaccompanied and unassessed would appear to be too risky.

The idea is for the rescuer to use the equivocation hitch to anchor the rope to the main belay so as to be able to ascend with the safety of a belay back-up but also release it from above by pulling on the release strand of the hitch. This would allow the rescuer to immediately transition to counterbalanced (CB) rappelling with the victim, which would save quite a bit of time by eliminating any weight transfers of the victim.

Of course, there would have to be a fairly free and direct line between the main belay and the victim to allow pulling on the release strand.

I have played with setting up the equivocation hitch in the regular rappelling anchor configuration and in the inverted configuration for an upward pull anchor attachment but I have not yet had a chance to practice the whole rescue sequence. However, it's clear that if there's a problem with this approach, it would not necessarily be revealed in a safe practice run at a single-pitch crag so a discussion is likely a better place to start.

Of course, this requires a long enough release strand. If the free end of the rope left after setting up the hitch will not be long enough to reach the victim, it would have to be extended with a second rope, a tagline or a makeshift tagline rapidly assembled from available cordage and webbing. The rescuer would climb/prusik up to the victim along the anchored rope, trailing the release strand loose behind him and making sure that he does not pull it tight in the process (which could release the hitch).

In the approach described earlier in this thread involving a short CB haul of the victim, transferring him to a load-releasable tether on an intermediate anchor to free his end of the rope and then transferring him back onto a tandem rappel system, the rescuer would aim to build the intermediate anchor a bit above the victim's final arrest position. With the equivocation hitch approach, the best place for the intermediate anchor would, instead, be as high up as possible. Since the rope would be left in the top pro to avoid the weight-transfers, the intermediate anchor may end up acting rather as a bombproof backup to the top pro, hence the importance of building it has high as possible (and of checking beforehand that the top fall-catching pro be - or at least look - solid enough to hold the combined static weight of the victim and rescuer).

The "better" option for the rescuer would be to keep an eye on the top fall-catching pro while ascending and, if it still looks solid as he gets up there and if there are options for additional pros just above it, to beef it up, equalizing the load with the additional pros as well as possible. However, that may not be feasible and the rescuer may have to opt for building a back-up anchor lower down. Of course, using this approach, there is a risk that, despite looking good, the top pro should fail before the rescuer has had a chance to clip the rope into the first back-up pro. If the top pro looks solid at first but, while ascending and getting a closer look, the rescuer decides that it no longer seems reliable enough, he would still have the option of building a proper intermediate anchor at a lower/safer location and transferring the victim to it using the hitch release and CB lowering.

Of course, this whole approach would be predicated on an equivocation hitch belay anchor being a "safe enough" anchoring system for this situation. As far as I know, it has only been tested as a rappel anchor. As such, it should be plenty strong enough to hold the victim's weight. The uncertainty concerns more specifically the possibility that the top pro (and all other pros located between the victim and the rescuer) should come to fail before the rescuer was able to complete the intermediate/back-up anchor. In this situation, assuming that a pro lower down would end up holding, the belay anchor would have to be strong enough to hold both the rescuer and victim falling together on the same side of the arresting pro (!!).

Thoughts? Critiques? Or better yet: realistic fall arrest testing, anyone?

I am well-aware that the equivocation hitch is not a particularly widespread rappelling technique so flipping it upside-down to use it as a releasable self-rescue belay anchor would obviously be fairly unorthodox. Between this and the potential risks, I can't imagine that this approach would ever end up being taught in a self-rescue course and I am definitely not suggesting it for people with limited self-rescue experience. However, as discussed before, in the situation of the leader dangling unconscious, with a high likelihood of serious further injury from simple lowering, there are no good (ie, safe all around) self-rescue solutions. The rescuer must choose between options that present significant risks either for the victim alone or for both.

To finish the portrait of this equivocation hitch approach: if the CB rappel does not reach a suitable ledge before the knot joining the rope and the rest of the release strand gets close to the rappel device, the rescuer would have to choose between starting CB climbing from that point while continuing to lower the victim to the ledge by "remote guidance" (provided, among various conditions, that the pitch's features that made it too risky to lower the victim in the first instance have mostly been cleared by then), or passing the knot with his rappelling device and continuing CB rappelling on the remainder of the release strand (provided that no more than one or two knots would have to be passed and that precautions would be taken to maintain adequate braking friction and prusik back-up if the rest of the release strand is a much thinner tagline-type cord).

the macrame (equivocation) is something ive tried for the fun of it ...

i can see it being useful when rapping of natural anchors ... but like all knots/hitches, one needs to practice em over and over again to be able to do it quickly and safely ... and i question how much practice one will get with it unless one is a canyoneer

if one is in an accident, i suspect conditions may not be the best on the way down, perhaps thats what caused the accident ... when one is cold, tired, hungry, being blasted with wind and pelted with rain in the dark ..

the macrame IMO has a greater "screw up" potential

KISS as much as possible

;)

The equivocation hitch is a bit more complicated to implement than the MMO but not by much and it's definitely no more complicated than the simpler hauling procedures. For most people, being able to do self-rescue procedures quickly and safely requires regular practicing. Doing them tired, cold, in the dark and the rain, etc. (as you usually like to point out ;)) will make everything much more difficult and that difficulty has to be factored in when selecting what to do and how to go about it.

In my experience, only in the most straightforward and textbook situations does the KISS principle really come into play in self-rescue. A lot of the time, self-rescue is going to be a special situation and often, paying attention to a particular detail early on in the procedure will make all the difference between the procedure working well or not working at all. Practicing whole procedures (as opposed to individual parcelled-out techniques) is the only way to realize the importance of these details.

Of course, if there’s a choice between equivalent procedures, one should always pick the simpler one but, as far as I know, there is no equivalent to the equivocation hitch approach (how’s that for alliteration?), let alone a simpler one. Compared to the nearest approach, the equivocation hitch approach implies a somewhat greater inherent risk in trade for a much faster end result in a rare situation when speed is vital. That alone should exclude it from the ranks of standard self-rescue techniques, so keeping things KISS for beginners is really not a concern in this case. I’m more concerned with whether, if implemented correctly, it is actually strong enough. If the answer is “yes (or “most likely yes”), as long as you don’t get catastrophic failure of all the pros clipped between the victim and rescuer and a hard (long) fall of both on the same side of the next arresting pro” then, the rescuer can factor this requirement in deciding whether to use this technique, its safer/longer alternative or the faster still but even riskier approach of not anchoring the rope at all. If using the equivocation hitch approach, a clearer understanding of its strength would also guide how to implement it. For example, the rescuer could place and clip one or two additional progression pros in addition to the intended back-up anchor as he gets near the top fall-catching pro and avoid at all cost being left with only that top pro between him and the victim.

Ha. When I first thought of using the equivocation hitch as a releasable self-rescue anchoring system a while ago and started wondering whether it would be strong enough, I briefly toyed with the idea of using instead the equivocation hitch to stop a Munter. It seemed that there should be a lot less doubt about the strength of this anchoring system since it would be fairly similar to an MMO but I figured that, since the Munter would stay threaded after releasing the equivocation hitch, it would prevent the knot between the main rope and the release cord from passing through the anchor biner, which would severely limit the usefulness of the approach.

I should have tried it rather than assume that it would not work. I just reread some notes and decided to try it tonight using a Petzl William as the anchoring biner and the EDK as the joining knot. As it turns out, you can quite easily get most knots to pass the Munter by just pulling (with a little shaking at the end). The knots joined the following cordage combinations: 5 or 7 mm nylon cord joined with 8 or 10.3 mm dynamic rope and all three combinations of the latter two (8-8, 8-10.3 & 10.3-10.3). I was able to quickly (between 5 & 20 sec. each time) pass the knot through the Munter and biner in all cases except the 10.3-10.3. In fact, it seems that there's really no such thing as the knot jamming the Munter. If the knot jams, it's because it's too big to get through the biner (with a fat rope Munter already clipped in it). A bigger biner would work for the 10.3-10.3 but, since it would be quite unlikely to have to tie a fat release rope to a fat climbing rope, going for a bigger biner would seem pointless.

Of course, pulling (and shaking) the rope while cradling an unconscious victim on a CB rappel is bound to be trickier than the little tests I did. I'll have to try and give this a more realistic test with one of my usual guinea pigs when I get back to the local crags but, in the meantime, this approach looks fairly promising, especially if no clear indication can be had as to whether the equivocation hitch proper would be strong enough for the job.

An important aspect of the "equivocation Munter" approach is to make sure that the Munter will stay on the wide end of the HMS throughout. To be safe, the rescuer should also stop the CB rappel well before the EDK arrives at the Munter. This way, if a hard jam should occur despite checking the combination of rope, release cord and HMS ahead of time, there would be enough slack for the rescuer to finish rappelling on his own, leaving the victim behind, to go release the jam. He could then choose among various options for finishing getting the victim down.

Of course this approach does not reduce the inherent risks associated with the possibility of the top pro failing so what I said earlier about this being unsuitable for beginner self-rescuers still holds.

MT head wrote:The n number of your study is 3?? You have more posts than you do with your "study" There is documented information on the cause of death in suspension trauma. Ranging from metabolic to severed aorta's. Your diagrams are down right dangerous and I would suspect any rigging course/SAR team would cringe at the very thought. Reading an article and experimenting with 3 volunteers is far from a gold standard in health care and best practice in the setting of Trauma. Sorry man but you sound dangerous.

It appears that you’re getting mixed up between my initial proposal of possible suspension positions and Dr. Bariod’s tests with a few volunteers in a clinical setting in France a number of years ago. If you read the thread more attentively, you’ll find that I completely accept that attempting to place the victim in a more or less horizontal position (the ones illustrated or any other) before the first desuspension is really not a good idea and I made that quite clear in the diagrams and addendum. It would take precious time away from getting the victim down and desuspended and, contrary to what I thought at first, the available literature does not indicate that pronounced and lasting benefits could be derived that would justify the necessary time investment.

Since I’m recapping the thread, I might as well indicate that in a situation when simply lowering the victim unassessed and unaccompanied would seem too risky, my current take on a leader dangling unconscious from the rope can be summarized as follows.
- After calling for help (and assuming that help is not immediately available), the belayer/rescuer escapes the belay, ascends to the victim and installs a solid intermediate or back-up anchor above the victim (different options possible depending on the intended approach for getting back down).
- Rescuer performs rapid evaluation of victim and most urgent first aid, including placing a padded SAM splint C-collar on him. Depending on the position of the victim, apparent solidity of the top fall-catching pro and various other factors, it may be best to install the C-collar as soon as reaching the victim to minimize the risk of jostling while setting up the anchor.
- Rescuer gets set up for rappelling (again, different approaches are possible involving, or avoiding, temporary transfer of the victim to the anchor).
- Rescuer rappels to the nearest suitable flat-ish surface (ledge or ground) with victim cradled in front of him.
- Rescuer transitions victim from suspended vertical rappelling position to desuspended horizontal position for further assessment and treatment. Doing this while keeping the victim’s head aligned is tricky and has not (yet) been discussed here.

I recently completed the tests and practices I had been planning and they went essentially as anticipated. I mainly wanted to test the two options discussed above for reaching and bringing back down an incapacitated leader. As discussed above and in Fasulo's Self-Rescue, there are risks involved with these options. These risks are not reviewed again in this post. I thought I'd just outline the main points of the tests.

The route used for the outdoor tests is about 13m high: less than vertical for the first 7m or so, transitioning to vertical over the next 4m and ending in a slight overhang at the top anchor.

1. Counterbalanced rappel off the fall-catching pro with a “releasable-from-above munter-mule-daisy (MMD)" anchoring the rope to the main (bottom) belay.

1.1. Hauling
Although not directly related to the main rescue exercise, I wanted to practice the Spanish Burton 3:1 hauling system (SB) and use this haul to get a heavy weight high up on the route, in a situation mimicking a leader dangling unconscious after a fall. In this practice, instead of a live “test victim", I used a large pouch filled with rocks collected around the foot of the route. I have no idea of its precise weight but I'm guessing that it was somewhat heavier than myself.

The haul was set up with two separate ascension systems: two regular (6mm) prusiks for ascending the belay side of the rope and resetting the SB haul cord and two 5mm prusiks for ascending the 7mm SB cord and raising the load (for better efficiency, as discussed in the long post at the end of this thread). Initially, I had to add a pull-up prusik loop to overcome the friction between the pouch and the wall. As friction decreased higher up, the SB without pull-up was enough to raise the pouch. It still took me about 40 min. to raise it 10m.

1.2. "Rescue of the leader”
The haul completed, I came back down and anchored the rope with a munter blocked by a mule followed by a tightly snugged daisy chain (MMD). The last (fourth) loop on the daisy was about 50 cm long to minimize the risk of accidentally unraveling the daisy. In previous posts, I discussed using the equivocation hitch to block the munter but, with the equivocation hitch, the blocking loops are set alternatively on each strand of the rope. This introduces loops on the loaded rope between the load and the munter. Not only would this be trickier to implement but it would also interfere with the Munter functioning as a braking system. I opted instead to use the mule and daisy loops to block only the brake strand, letting the loaded strand go straight to the munter in the normal way.

The Munter was set on a Petzl William clipped to an upward-pull sling (attached to a tree). The biner was maintained in the correct orientation (anchor sling at the narrow end and munter on the wide basket) by an elastic band wrapped over the biner and the sling. This avoids the risk of the munter sliding away from the biner's basket, which might prevent passage of the knot during the rappel (see below).

About 3m from the tail end of the daisy, I tied a knot in the rope to mimick the likely situation where, the leader having fallen much higher up on a long pitch, an extension would need to be attached to the end of the rope to allow releasing the daisy from near the victm.

I then re-ascended with the free end of the rope clipped to my harness. Once I arrived just below the pouch, I took in the trailing rope and yanked on it to release the daisy and mule and started the CB rappel. I stopped when the knot in the rope got close to the munter and pulled and shook the knot through the Munter, which took all of 15-20 sec. I then finished CB rappelling back to the ground.

This self-rescue part of the test, from setting the MMD to bringing the pouch back to the ground took about 12-13 min. In a real situation, I would have needed to escape the belay first and set the ascension prusiks from scratch, which would have added about 5-6 min. Of course, since the leader would have been located much higher, ascending to him would have taken longer as well. Depending on the circumstances, I might have needed to pass the knot through the ATC during the CB rappel. On a trad climb, I would also have needed to collect pros from the leader's rack and convert the top fall-catching pro (or a lower progression pro) into a solid anchor as discussed previously. This might take 4-5 min. if a good second pro placement is easily spotted near the first one and if the corresponding pro is readily obtained from the leader's rack, but could potentially take quite a bit more if, for example, the good second placement is further out and/or difficult to gauge, if there is no pro on the leader's rack that fit the better placement; if a third pro is needed; etc. Of course, this does not include either the time needed to perform a rapid preliminary assessment of the victim and provide the most urgent first aid prior to rappelling.

1.3. Strength of the munter-mule-daisy
I tested the strength of the MMD by using it to attach an old 8.5mm rope between my AWD car's 2 in. trailer hitch and a large-ish tree in my front yard. I did not push the test until spinning the wheels but still gave it a pretty strong tug. What I found most encouraging is that after this, it was still quite easy to pull on the release strand of the rope and undo the daisy and mule loops, indicating that the munter did exactly what it was supposed to; ie, lock up the rope without slipping or transmitting the pull to the mule and daisy loops.

1.4 Knot-passing through the munter with a live test victim
An additional test was done on a gym TR route to determine how easy or difficult it might be for the rescuer to pass the knot through the Munter on a CB rappel with a live test victim. This test was also quite encouraging. Obviously, it was a bit more fiddly to pull and shake the two strands of rope with both hands behind my back while keeping my test victim cradled in front of me and avoiding jostling her but I was still able to get the knot through the munter in under 30sec.

2. Using a short counterbalanced haul of the victim to transfer him to the secondary anchor, detach and recover his rope and set up a tagline tandem rappel

This second test was done on the same outdoor route but on a different occasion and with a live “test victim”. The secondary anchor was simply a long-sling extension off of the main TR anchor. The test victim climbed up to about 2m below the sec. anchor and stopped there, mimicking having fallen on lead (and, if necessary, been lowered a bit more to that convenient spot by the belayer). I then escaped the belay and left my test victim secured on the rope with an MMD attached to the tree at the base of the route.

I clipped the free end of the rope to my harness and got up to just above my test victim using a combination of climbing and ascending on prusiks. I then counterbalance-hauled her up to the secondary anchor (1:1 + pull-up); and secured her there with a short MMO on a cord sling girth-hitched to her belay loop (clipping her dynaconnexion loosely, as well, as a back-up). I then secured myself to the secondary anchor with my own dynaconnexion.

I detached my test victim's knot, recovered the rope from the top anchor and installed it in a reepschnur-like tagline rappel configuration anchored to the secondary anchor, using as the tagline the free end of the rope I brought up attached to my harness.

I then transferred myself to the single-stranded rappel rope, setting the 3rd hand and wrapping the rope around my thigh, clipped the test victim’s dynaconnexion to the ATC, released her sling MMO link to the secondary anchor, transferring her to the ATC, and tandem-rappelled back down with her cradled in front of me. This procedure took about 25 min., to which the building of the secondary anchor, the preliminary assessment of the victim, etc. would need to be added, as discussed for the first test.

While the MMD appears encouragingly solid, I am well-aware that the test described in 1.4 was not representative of the forces involved in the kind of unlikely (but pretty dire) worst-case scenario for this procedure discussed earlier. Nevertheless, I choose to trust the MMD and feel that, in this type of situation, I would be happy to use it to anchor the rope to the main belay regardless of which of the two options I anticipated using to accompany the lowering of the victim. If the following conditions are met, I would opt for the first, much faster method; otherwise, I could always fall back on the longer but somewhat safer second option. I should also mention that while I might trust the MMD well enough for this particular self-rescue situation, I would continue to prefer the standard munter-mule-overhand for most other belay escape and weight-transfer situations.

Conditions for first option (second is fall-back option)
a. I am able to quickly extend the free end of the rope to make a long enough (or close to long enough) pull cord before ascending (ie, one that should extend all the way to the position of the victim). If what can be assembled before starting to ascend falls quite short of the full height needed, the second option immediately becomes the better one. As mentioned previously, in this case, the top half of the makeshift tagline is assembled from cordage taken from the leader's rack and joined to the bottom half on the way back down.
b. The top fall-catching pro and the last few progression pros below it look solid and keep looking solid as I ascend;
c. I am able to either convert this top pro into a 2-pro anchor or set up a solid back-up anchor just below it (or, instead of points b & c, if the top fall-catching pro happens to be a solid bolt or pin); and
d. There is a fairly direct line of sight (and cord pulling) between the victim and the MMD to allow releasing the cord.

Wow!
I have not read the whole thread.
Jktinst, your thorough analysis, while dwelling on these important subjects is commendable!

I would not have ever lead a pitch if I had filled my head with so many

What Ifs. . .while I do appreciate that you have picked important subjects

You need some professional help. . .ho wait . . .right here in this thread
You have had the cream of professionals. They run the gammit from life savers to the mop up crew, and what ever has been respectfully shared has not gotten through to you?

Michael Schneider wrote:Wow! I have not read the whole thread. Jktinst, your thorough analysis, while dwelling on these important subjects is commendable! I would not have ever lead a pitch if I had filled my head with so many What Ifs. . .while I do appreciate that you have picked important subjects You need some professional help. . .ho wait . . .right here in this thread You have had the cream of professionals. They run the gammit from life savers to the mop up crew, and what ever has been respectfully shared has not gotten through to you?

YOU ARE SO MEAN...i was going to suggest knitting. Except those needles...has anyone done an analysis of potential eye loss? I mean, we can't take them on planes, they must be dangerous....

Michael Schneider wrote:Wow! I have not read the whole thread.

Or even enough to understand anything about it but why let that stand in the way of a delightful bit of flaming...

Michael Schneider wrote:... I would not have ever lead a pitch if I had filled my head with so many What Ifs...

You make it sound as though you don't want to know or think too much about climbing self-rescue because you like climbing, understand that it's dangerous in a vague and undefined way but could not stomach being forced to realize in what many different ways it can be dangerous. And I'm the one being told to take up knitting...

Michael Schneider wrote:... while I do appreciate that you have picked important subjects You need some professional help. . .ho wait . . .right here in this thread You have had the cream of professionals. They run the gammit from life savers to the mop up crew, and what ever has been respectfully shared has not gotten through to you?

This is really quite funny since this is one thread where I did substantially revise my initial thinking, thanks to constructive criticism. Unfortunately those criticisms did not point to solutions to the main issue of the thread, which is one of the more intractable problems in climbing self-rescue. They only pointed to problems with my initial thinking, which was based on other apparently authoritative material. I carried on adding to the thread because I thought of other potential solutions, which also evolved over time.

jktinst wrote: This is really quite funny since this is one thread where I did substantially revise my initial thinking, thanks to constructive criticism. Unfortunately those criticisms [which DID] point to solutions to the main issue of the thread, [HOWEVER, I chose to ignore all that and over-thought the problem anyway just so I could continue to write a bunch of gibberish]. ...

ftfy