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 Walter Cannon decided he had erred, and rescinded his recommendation for the use of Trendelenburg position in the treatment of Shock.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.
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