26 August 2008

Standing Trendelenburg on it's Head

He didn't work on Shock, and neither does his position, Dammit.

Friedrich Trendelenburg (May 24, 1844 – December 15, 1924) was a German surgeon and son of the philosopher Friedrich Adolf Trendelenburg. A number of medical treatments and terminologies have been named for him. He is perhaps best remembered for the Trendelenburg position in which the patient is placed on a bed which is put into incline such that the patient's head is lower than his feet. Trendelenburg first used this technique in 1881 for an abdominal surgery. (Wiki)
During World War 1, Walter Cannon, an American physiologist, and the same guy that coined "fight-or-flight", as well as developing the theories of homeostasis, popularized the use of Trendelenburg position as a treatment for Shock. 10 years later, he changed his mind.

Ladies and Gentlemen, in case you were absent, sleeping, or ignorant during that block of instruction, the First World War, the Great War, the War to End All Wars took place primarily in Europe from 1914 to 1918. The Treaty of Versailles was signed 28 June 1919.

WW1 ended Ninety years ago. So, at the latest, 80 years ago Dr. Walter Cannon decided he had erred, and rescinded his recommendation for the use of Trendelenburg position in the treatment of Shock. There are 12 listed surviving Veterans of that Conflict. Unlucky Thirteen if you count the Position that inspired this post.

Trendelenburg is still a fixture in initial management of Shock. Despite the fact that it doesn't work, and is potentially more harmful. The theory WAS that by elevating the lower portion of the body, either through Trendelenburg Position or passive elevation of the lower extremities, one could effect a form of autotransfusion, in which blood would be shunted "to the core". In the few studies that support this belief, performed on healthy subjects, these positions increased left ventricular filling, stroke volume and cardiac output, but the effects were transient and returned to baseline within 10 minutes. Conversely, numerous studies show that lung volumes are compromised by the weight of the viscera upon the diaphragm, and increased stress is placed upon the right ventricle. There is also evidence of increased risk of retinal detachment, brachial nerve paralysis, and of course, cerebral edema.

What's even more worrisome than the continued insistence of Trendelenburg, is the lack of elucidation. Individuals are taught to use Trendelenburg for Shock, but never which Type of Shock this nonsense supposedly works on.

Is it intended for Obstructive Shock? No, only relieving the obstruction will help. But you go right ahead, make that PE, tamponade, or pneumothorax dependent. It seems like a good idea to me.

Is it intended for Distributive Shock? As in neurogenic, septic, or anaphylactic shock. Nope, turning a patient upside down doesn't make "the Tank" any smaller. However, every patient with wheezing, urticaria, and profound angioedema LOVES being stood on their head.

Is it intended for Endocrine Shock? Does gravity have any effect on hormones?

Is it intended for Cardiogenic Shock? Like patients who can't breathe, myocardial infarction patients, and CHF-ers LOVE lying down. Even better if you can INCREASE the strain on their heart. Choke yourself.

Trendelenburg Position was intended for use during Hypovolemic Shock. Back in 1917-ish. Then Dr. Cannon changed his mind. Yet just about every where you go, "lay 'em down, raise their feet" is a given when it comes to initial management of a Shock patient. FR, First Aid, BSA, Brady, DOT, AAOS, NR, U.S. Army...

During the second stage of Shock, the Compensatory Stage, the body employs multiple physiological mechanisms in an attempt to reverse the condition. These include neural, hormonal, and bio-chemical mechanisms. I'm not going to get into Acid-Base balances, or renin-angiotensin, etc.

What I will discuss is the action of the carotid baroreceptors. The baroreceptors in the carotid arteries detect hypotension, and signal the release of adrenaline (epinephrine) and noradrenaline (norepinephrine). These are catecholamines with dual roles as hormones and neurotransmitters. Noradrenaline predominately causes vasoconstriction (α1) with a mild increase in heart rate, whereas adrenaline predominately causes an increase in heart rate (β1) with a small effect on the vascular tone; the combined effect results in an increase in blood pressure.

The body is an amazing machine. It manages to compensate, quite well. However, by throwing the legs up, or standing someone on their head, you manage to deceive the carotid baroreceptors into thinking the body has adequate blood volume, and pressure. In turn, they do not trigger the release of catecholamines. The body doesn't get the message to compensate. As soon as that Transient effect of standing them on their head subsides, you succeeded in helping the body skip right through Stage 2 of Shock, and right into Stage 3, the Progressive stage, or more ominously: Decompensation.

There are, however a few appropriate uses for Trendelenburg.
  • Abdominal surgery (HOLY SHIT, that's what it was intended for!)
  • Central Venous Line Placement in the jugular or subclavian veins. I'll extend that to EJ's for you Paramedics, but the arms of a stethoscope kinda work better.
  • Reducing abdominal hernias. For the same reason it's used in abdominal surgery.
  • Waterboarding. Yeah. Because of it's negative effects on breathing and airway. Fuckin' Terrorists.
  • Various obstetric and gynecological procedures, or practices.

As Usual, Dr. Bledsoe knows what's up.

  • Martin JT. The Trendelenburg position: a review of current slants about head down tilt. AANAJ 1995;63:29-36.
  • Ostrow CL. Use of the Trendelenburg position by critical care nurses: Trendelenburg survey. Am J Crit Care 1997;6:172-6.
  • Taylor J, Weil MH. Failure of the Trendelenburg position to im-prove circulation during clinical shock. Surg Gynecol Obstet 1967;124:1005-10.
  • Sing RF, O’Hara D, Sawyer MA, Marino PL. Trendelenburg position and oxygen transport in hypovolemic adults. Ann Emerg Med 1994;23:564-7.
  • Terai C, Anada H, Matsushima S, Shimizu S, Okada Y. Effects of mild Trendelenburg on central hemodynamics and internal jugular vein velocity, cross-sectional area, and flow. Am J Emerg Med 1995;13:255-8.
  • Bivins HG, Knopp R, dos Santos PA. Blood volume distribution in the Trendelenburg position. Ann Emerg Med 1985;14:641-3.
  • Sibbald WJ, Paterson NA, Holliday RL, Baskerville J. The Trendelenburg position: hemodynamic effects in hypotensive and normotensive patients. Crit Care Med 1979;7:218-24.
  • Reich DL, Konstadt SN, Hubbard M, Thys DM. Do Trendelenburg and passive leg raising improve cardiac performance? Anesth Analg 1988;67:S184.
  • Terai C, Anada H, Matsushima S, Kawakami M, Okada Y. Effects of Trendelenburg versus passive leg raising: autotransfusion in humans. Intensive Care Med 1996;22:613-4.

17 comments:

TOTWTYTR said...

Not that you have any strong feelings about the matter.

Terrific, fact filled, rant. We mostly don't use Trendelenburg any longer, but of course, like "Tourniquets Bad" and "Pulse Ox Good", it persists in the mythology that is EMS teaching.

Sadly, 90 years from now all three will STILL be taught in EMT classes.

ParaCynic said...

TOTWTYTR:

Thanks for commenting. At least I know one person reads me.

Many people with common sense don't use Trendelenburg. Yet, as you said, they still teach it. Also, I still have EMTs and Medics, both new, and experienced, try to convince me it's "the right thing to do".

Gertrude said...

That was a great post and I agree 100%. I'm not a hu ge fan of the position and don't use it. It was great to see the facts behind it, now I have someting to show my students that is more entertaining than reading it in a text book.

ParaCynic said...

Gertrude:

Thank you for the kind words. Hope the knee is on the mend.

Rogue Medic said...

Great post.

Just the right amount of sarcasm. :-)

Is it possible to have too much sarcasm?

I will get something up in response to Bostonian in NY's last comment. It will probably be longer than your post, but there is so much wrong about the EMS approach to tourniquets and Trendelenburg.

I'll let you handle the tampons and toilet paper, although the use of tampons does seem to correlate with a woman feeling more of the effects of gravity, so maybe gravity and hormones are related. :-)

TOTWTYTR said...

Paracynic, RM knows sarcasm, so this is high praise indeed.

To paraphrase Ronald Reagan,

"The trouble with most medics and EMTs is not that they are ignorant, but that they know so much that isn't so."

30 yr ff/pm said...

Retinal detachment?
Ahem..[cough]bullshit[cough]

You don't have to stand the patient on their head, just a slight elevation of the feet will do. 6 inches is usually enough to help if it's going to.

I'll take 10 minutes of help while I do my part to stop the leaking and refilling the tank.
If it pumps up that subclavian or internal jugular I might stick, so much the better.
Also comes in handy for the vaso/vagal syncope that may not need much further intervention. Supine works too, a little leg tilt is faster.

True Trendelenburg is the patient at a 45 deg angle. NOBODY has ever been placed in that position that I have witnessed.

30 yr ff/pm said...

I meant to add to the last post:
Rouge Medic: Just the right amount of sarcasm.
(you rosy cheeked devil)

Agreed, and just poking fun.

ParaCynic said...

30: Thirty years of voodoo, misguided efforts, and lifesaving salt water? No wonder this kind of thing perpetuates, and still gets taught. Don't do something just for the sake of doing it.

The sad thing is, you call the retinal detachment "bullshit" yet there is more evidence (albeit not a lot) to it's credit than in support of the efficacy of leg-lifts.

Next, trendelenburg in syncopal episodes of unknown etiology is generally a no-no.

Further, I'm hoping you left some credentials off your name, because if you're practicing subclavian lines and IJs on your ALS Engine, methinks you might run into some issues with scope of practice.

30 yr ff/pm said...

Next, trendelenburg in syncopal episodes of unknown etiology is generally a no-no.

You've never raised someones feet a few inches and they felt better and their vital signs improved??

Remember, I'm not advocating "standing pts on their head." (As far as retinal detachment goes, I would think that sneezing would be a far greater danger.)
Raising their legs is just a tool, that's all.
Just like infusing IV fluid is a tool to break the shock cycle.
I'm just saying that when you toss the bath water, make sure the baby is not in it.

if you're practicing subclavian lines and IJs on your ALS Engine, methinks you might run into some issues with scope of practice.

You think Docs are the only ones to do this?
Maybe in your state.
I've done quite a few, actually not that big a deal.
Will I take a peripheral line instead? Absolutely! Every day of the week and twice on Sunday. That's all fine if your pt has their periphery intact, some don't.
The only way to support the central circulation in those pts is to access it. Sometimes you gotta do what you gotta do.

ParaCynic said...

30: I rank that right up there with telling crowds to "back up and give them some air". It has no effect on the actual patient. It does, however, make it look like you're doing something, while giving nature a chance to run its course.

Lifting someones legs up will not cause them to come around, or improve, any faster, whether it's true Shock, or just psychogenic drama.

We were talking about Hypovolemic shock, not Psychogenic shock. But still, lifting a dramatic cry-babie's legs doesn't make them any less of a dramatic cry baby.

Rogue Medic said...

30 yr ff/pm said...

"Rouge Medic: Just the right amount of sarcasm.
(you rosy cheeked devil)"

Well, I eventually worked my way up from EMT-Blush and I am just demonstrating that I am not anemic. Part of it is TOTWTYTR's complement about my sarcasm. And I like to Rouge it up, when I am in Trendelenburg position.

Retinal detachment is not likely, with the minimal amount of elevation that you recommend. The problem with Trendelenburg is the lack of research to support it and the complications that may complicate care of these patients.

GERD is a growing problem. Hey, I'm a double threat - sarcasm and puns. This is a problem for people who do not have their legs elevated at all (the GERD and the puns). Raise their legs and you increase the chances of the stomach contents wandering into the airway. The puns are usually not that dangerous.

A risk vs. reward formula without any research to suggest that the benefit is worth the risk. And that is not the only risk.

ParaCynic said...

Rogue:

I failed to mention GERD and misplaced gastric contents, I apologize profusely.

Those are things I just take for granted. Due to our chosen vocation, I think most of us suffer from them at the semi-fowler's, fowler's, anatomical, fetal, sniffing, well, just about any damn position.

Oh...my agida...

Medic13 said...

I have heard this before and truly believe it. The only reason I'm actually leaving a comment is because you mentioned using the scope for ej placement, I've never heard of that and was curious how you go about doing that.

ParaCynic said...

Medic13:

The "arms" or earpieces, or whatever you prefer to call them on your stethoscope. If you place them around the lower portion of the patients neck, and they've got enough "spring" to them, or if you apply slight pressure, they'll cause the EJ's to engorge.

It works even with a patient in full-fowler's. More importantly, you get less funny looks than when you put a constricting band 'round their neck.

Hope that helps, it's easier to show than describe. I guess my words are a lousy paintbrush.

first rule of fire said...

Great post. I agree and I am not worried about retinal detachment with these patients.

How do we know that raising a patients legs 6" speeds things up? Is there any research to support this semi-kinda-almost Trendelenburg position? Do we just feel that what we are doing is making a difference because we are doing it? It would feel pretty silly to be doing this and just making the patient worse off.

Keep 'em coming.

Anonymous said...

I have been a nurse anesthetist for 31 years. In this time period I have met only one anesthesia provider that agrees with me on the nonsense of the Trendelenburg position being the way to "treat" hypovolemic shock. It is virtually impossible to get anyone to actually think about what this position actually does to the body. It's one of those things that they were taught and never really examined nor do they want to examine it. It is just accepted as gospel. I was glad to find your post while researching articles to support my views on Trendelenburg. I my mind this concept is right up there with the well-known fact that if you go outside in cold air without a coat you will "catch" pneumonia and God forbid you go out with wet hair. I've always wanted to ask people what part of our body does this "catching".