Author Topic: Emergency Medical Knots  (Read 9550 times)

Son of Liberty

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Emergency Medical Knots
« on: November 18, 2009, 05:37:22 AM »
Hello,

I'm taking an EMT class.  In this class we are allowed to use any knot we like to secure our splints and bandages.  Our instructor uses something that I have concerns over.  It's just the beginning of a Surgeon?s Knot--(the ropes are twisted together twice).  This "knot" is easy to synch down, and when tied against a surface where pressure is pushing against the knot, such as a body part, it seems to hold tight; but, I fear that continued movement will allow the knot to loosen and slip, compromising the effectiveness of the overall splint.

Does anyone have any suggestions of knots I could use?  Keep in mind that they should be able to be tied quickly and in cramped spaces such as a crashed car.  I've tried the Surgeon's Knot, but sometimes it seems to loosen while I'm tying it.  Maybe I should just get better?

For a little background info, we generally use triangle bandages, which are basically triangular pieces of cloth rolled into a long, thinner bandage.  Our splints are usually thin and flat, about 4 inches wide.

Thanks,

Son of Liberty
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--Brave Heart

Dan_Lehman

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Re: Emergency Medical Knots
« Reply #1 on: November 18, 2009, 07:17:10 AM »
It's not clear what materials you're working with in trying to tie
some quickly secure binding:  you mention both "ropes" and
some "triangle bandage, rolled up". ??

Here's a quick idea:  make an Overhand Noose in one end
(this might be regarded as a "Slip Knot", but the difference
is that the "slipping" part --what moves-- is the main line,
not the end);
insert the opposite end through the noose eye, and even
make a 2nd insertion (somewhat *surgeon*ish, this),
and then pull back on this inserted end to pull thing tight,
which should capsize the twist in the noose eye such that
the eye is now a full round turn (double turn) around the
end, AND further tightening will tighten this noose's turn's
grip on the end (which you could at some point tie off
in a bona fide Slip Knot (end moving, for easier untying),
to completely prevent it from sliding back through the
noose's grip.

NB:  one can reeve the end around either side of the noose's
eye legs --i.e., around the side leading to the Overhand knot,
or around the side that is leading out to the main rope binding.
The difference will be whether this short coil is loaded like
a Rolling Hitch vs. the ProhGrip (Blake's; also Klemheist) hitch.
Both seem to work (though in one case with here some soft-laid
3/8" nylon, the lay is grossly distorted.  YMMV.

.:.  You want quick, simple, effective; EMT folks & hospitals
are (too) happy to cut bindings later (I lost a rope belt after
an accident, alas).  This knot should be able to be manually
further tightened or loosened, one hand grasping the knot
body, the other pulling the inserted end whichever way is
desired.  No rope need be harmed in this binding!   ;)

Your thoughts about the vulnerability of the double twist
that your instructor is using are right on target:  that requires
backing which might never adequately be there, or, as you
remark, might disappear with some movement & shifting.
(I have it from a doctor acquaintance that surgeons in fact
never use this so-called knot -- much like the Dutch Navy
probably hasn't got some different bowline, or Stevedores
their own stopper, or ... -- knotting, a world of myths!)

--dl*
====

ps:  In anticipation of things to come:
  No, the Gleipnir is nota workable solution here!   :)

DerekSmith

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Re: Emergency Medical Knots
« Reply #2 on: November 18, 2009, 02:46:34 PM »
Hi SoL,

I think that you probably are already dealing with the optimal binding for this situation - vis triangular bandage and double wrap OH knot.

For this application the knot must be easy to tie (I doubt there is anything easier than the OH and the extra wrap is trivial).
It must be easy to adjust - both tighten and slacken.
It should not jam.
It should spread the load over tissues so as not to cut off blood flow.
It should not have any 'leverage' so that the technician can easily sense the amount of force being applied.

The double wrap OH does all of these things and can be tied in materials (triangular bandage) that are always available (or can be easily made).

The knot may seem flimsy, but it is being held together by friction and the resistive back pressure of the limb it is holding.  Neither the friction nor the back pressure are  likely to go away, so the knot will stay in place at the tension it was set at.  Movement will increase the back pressure which will simply increase frictional grip and maintain the hold.

When making up the 'ropes' be careful not to make the triangles into stiff round 'ropes'.  These will not grip as well and will also tend to 'cut in'.  Aim for a reasonably loose 'scrunch', the more uneven the 'rope' is as you pull up the knot, the better the frictional grip will be.  If for any reason you are still unhappy that it might slip, then just tuck the ends under the binding to give even more frictional grip.

The other thing to remember is that the splint is likely to be bound by multiple ties.  Each one is taking a little of the load, so none of them are having to do too much work and you can check and adjust each one for tightness without needing to fiddle with any of the others. The only fix that is likely to be better is probably the 'air splint' which can give an even more uniform application of the controlling forces, or velcro ties, but you cant make these up from material at hand when most needed.

Derek

capt larry

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Re: Emergency Medical Knots
« Reply #3 on: November 18, 2009, 03:28:46 PM »
SOL,

I am entering my 25th year as a member of the National Ski Patrol.  Our original training was Red Cross Advanced First Aid augmented by special Ski Patrol training.  In 1989 Ski Patrol wrote its own course based on the National DOT program developed by the  College of Orthopedic Surgeons for EMT-B, now called Outdoor Emergency Care. It is styled "emergency care for the non-urban rescuer, ie: no ambulance and its equipment, more than an hour to definitive care."  I have also been an EMT.  Additionally I have taught and been an Instructor Trainer for Ski Patrol. You are being taught the customary method of tying cravats (triangular bandages).  These are fabric, usually muslin which is of coarse texture, and will hold a knot quite well.  The standard reef or square knot without the additional twist of the so called "surgeons knot" is perfectly adequate in this material.  Most important, it is easy to remember and quick to tie - generally speed is of essence in emergency situations - remember the "golden hour".  While your concern is understandable from a theoretical point, I have not seen failure of the properly tied reef knot in annual refreshers, classes taught or in the field.

Caveat: my remarks are limited to tying cravat bandages.  Since use of rope or cords in these situations would create a tourniquet - an undesired outcome - I think you are safe to follow the instructions given when using cravats.

You will also find that in actual practice, cravats are largely replaced by various splints which are quicker and easier and do not require knots as they fasten with velcro and such.

Hint: When tying a cravat around a person's torso eg. to treat fractured ribs, have the patient take and hold a breath when you tighten and tie the knot and it will then be nice and tight.

Wishing you success in your course.

CL

roo

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Re: Emergency Medical Knots
« Reply #4 on: November 18, 2009, 06:24:26 PM »
Hello,

I'm taking an EMT class.  In this class we are allowed to use any knot we like to secure our splints and bandages.  Our instructor uses something that I have concerns over.  It's just the beginning of a Surgeon's Knot--(the ropes are twisted together twice).  [...], it seems to hold tight; but, I fear that continued movement will allow the knot to loosen and slip, compromising the effectiveness of the overall splint.

Then demonstrate to your instructor how it would loosen.  Use the same materials and try to replicate actual usage as best as you can.  Then, you could demonstrate how a reef knot, for example, performs better under the same real-world conditions.  

« Last Edit: November 18, 2009, 06:25:32 PM by roo »
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Son of Liberty

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Re: Emergency Medical Knots
« Reply #5 on: November 19, 2009, 12:17:20 AM »
Thanks for all the insight guys.  I'll start playing around with some cravats and test everything out.

While we're on Emergency Knots, I thought I'd ask some more questions:  We haven't gone over this situation in class yet, but if we had to lower a patient from an elevated place on a streacher, what knots would you use to attach the rope to the streacher, and what type of rig / pully / system would you use to actually lower the person?

I'm not sure what the rope would be made out of, but it would probably be fairly thick and strong.  The strecher should have some holes in the side of it that you could slip a rope through.

Thanks

Son of Liberty
« Last Edit: November 19, 2009, 12:24:37 AM by Son of Liberty »
All men die.  Few men really live.
--Brave Heart

roo

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Re: Emergency Medical Knots
« Reply #6 on: November 19, 2009, 01:21:19 AM »

While we're on Emergency Knots, I thought I'd ask some more questions:  We haven't gone over this situation in class yet, but if we had to lower a patient from an elevated place on a stretcher, what knots would you use to attach the rope to the streacher, and what type of rig / pully / system would you use to actually lower the person?

I'm not sure what the rope would be made out of, but it would probably be fairly thick and strong.  The stretcher should have some holes in the side of it that you could slip a rope through.


That's kind of an open-ended question.  How short on equipment are you?  Are carabiners allowed/preferred?  Is more than one rope allowed?  Is pre-rigging the stretcher allowed?

I could imagine two somewhat short ropes, one on either side of the board, attached at the head and foot ends with the loop or hitch (and maybe carabiner) of your choice.  Then, you fold these two side ropes up over the victim to allow a grippy hitch from the main (vertical) hoisting rope encircle the two side ropes:

e.g. http://notableknotindex.webs.com/sailorhitches.html

In this way, the hitch can be slid (while loose) to coincide with the center of gravity of the victim.

If you want, you could put an on-the-bight loop at roughly the center of each of the "side ropes" to attach a carabiner or a loop knot:

ref:
http://notableknotindex.webs.com/butterflyloop.html
http://notableknotindex.webs.com/zeppelinloop.html
http://notableknotindex.webs.com/waterbowline.html
http://notableknotindex.webs.com/gnathitch.html

etc.

The rigging question regarding lowering seems a bit too open to approach, but I'll give a link for thought:

http://notableknotindex.webs.com/friction.html
« Last Edit: March 22, 2012, 06:51:24 PM by roo »
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capt larry

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Re: Emergency Medical Knots
« Reply #7 on: November 19, 2009, 03:51:38 PM »
SoL,

This is a huge topic. I doubt you will find a lot about it in a basic EMT course unless it is one of the wilderness programs.  Also, collateral to lowering a person is raising someone out of a ravine or gully.

The first order of business is to securely position the person on a backboard.  These usually have holes or slots where ropes can be attached.  Generally the straps that are affixed to stretchers are not sufficient.  There are commercially available "spider" straps or you can improvise with inch wide nylon straps.

There are various devices commercially available to provide friction and allow easy lowering or braking on lifts.  In ski lift evacuation, we use a harness with a figure 8 attached.

The ropes used would be those used by climbers, called kernmantal.  Probably 1/2 to 5/8 inch diameter with high breaking strength of 7,000 pounds or more.

Roo gives some good examples of knots to be used.  Generally, the standard Bowline is not considered acceptable in situations involving a person's life.  There is a long thread on this forum about this topic. http://igkt.net/sm/index.php?topic=1202.0

You might find interesting this knot developed by a fireman for rescue work. http://www.karashknot.com/

Lastly, you should check out the sites and forums involving climbing, caving and search and rescue.

CL

Dan_Lehman

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Re: Emergency Medical Knots
« Reply #8 on: November 19, 2009, 07:50:40 PM »
While we're on Emergency Knots, I thought I'd ask some more questions:  We haven't gone over this situation in class yet,
but if we had to lower a patient from an elevated place on a streacher, what knots would you use to attach the rope to the stretcher,
and what type of rig / pully / system would you use to actually lower the person?

These are questions with well-established answers given in various books
that you should seek, e.g.:
  •   CMC Rope Rescue Manual (3rd ed.; James A. Frank);

  •   Engineering Practical Rope Rescue Systems (Michael G. Brown);

  •   High Angle Rescue Techniques (Tom Vines & Steve Hudson);

  •   Technical Rescue Riggers Guide (Rick Lipke)

You can acquire these via Amazon.com, and maybe cop a deal for the
bulk order.  SAR teams will want some commonality of procedure vs.
ingenuity (which has benefits, along with some limitation).  From a
quick scan of above, it seems that the actual connection to a litter
is with large 'biners (big expensive steel, likely), which themselves
are clipped into Fig.8 eyes, and that back to some special collecting
device to bring the four legs of litter support together to the raising
or lowering rope(s).  And there are procedures for how to secure
the patient into the litter, usually with 1" tubular tape (I'll guess).

It is a hope of mine that a secure version of the Bowline can be
introduced to the SAR world and incorporated into their standard
practice.

--dl*
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PatDucey

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Re: Emergency Medical Knots
« Reply #9 on: November 20, 2009, 09:10:30 PM »
I used to be an EMT, but I let my certification lapse, as I am no longer working as a volunteer firefighter.  I have never had an issue with the surgeons knot slipping when tying a creveat.  The surgeons knot is a two part knot, and when the second overhand knot is tied over the fist double tucked overhand, it should hold under reasonable use.  You can always add another overhand knot on top if it is slipping.

You will find that there are many bandages that you will train with that you will never see in the field.  I am a first aid responder at the shipyard I work at, and get a call about once a week.  I have yet to use a creveat.  I use a stretchy self stick first aid wrap, and when we call the EMT's for something good, they are using the same stuff.  When we had to get a guy off of a boat that was in the yard (30' above concrete), we used the Velcro straps that come with the backboard to secure him down.  We didn't feel it was enough, so we used duct tape to fasten him down.  Duct tape works great, and when the EMT's showed up, they loved it, (mostly cause they didn't have to go up on the boat to treat him).

If you end up on a high angle rescue, hopefully you will have an experienced high angle rescue team with the correct tools.  If you have a pre-rigged harness, great, but if not, I have found that the best knot to make a loop at the end of a line is the bowline.  You should practice tying it around something, behind your back, in the dark, with gloves on, while it is raining.  Hopefully you will never have to tie it in a more difficult situation.  As to a pulley/lift rig, I have found that simple is best.  Get four or five of your fellow firefighters, grab the rope, and haul away.  If you are alone, you will have to improvise.  But if you are responding on the job as an EMT, you will always have team members close by.

Pat

Son of Liberty

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Re: Emergency Medical Knots
« Reply #10 on: November 22, 2009, 03:26:31 AM »
Thanks everyone.  These are some great thoughts.  I'll practice with them all right away.

--Son of Liberty
All men die.  Few men really live.
--Brave Heart