Inclined Bed Therapy (IBT) How is everyone?

[Adrian]

The video shown shows clearly how a downward flowing liquid initiates a return flow. There is no need to hypothesise that Brownian Motion is required to generate a return flow, because BM is multidirectional and totally random so therefore cannot be considered as generating a return flow. It is the molecular drag from the downward flowing CSF which generates the pull required to circulate the CSF. http://www.youtube.com/watch?v=zNJHChtHklg

The video clearly shows the rationale behind a siphon, as could be explained in any 12 year old's physics class. I agree that Brownian Motion is not needed to explain return flow but it is the paper you link to that concludes that the upward flow is caused by Brownian Motion, hence your statement that there is no need for Brownian Motion to cause a retunrn flow is correct but you are disagreeing with the conclusions that are offere by the paper you link to. Posting a paper that you claim supports your case and then disagreeing with it does not make a convincing case.

The paper you link to makes many spurious claims about temperature difference and brownian motion being the driving forces behind CSF flow. However, the reality is that CSF flow does not require these forces to maintain its flow:

http://sikermedical.com/services/mri/mri_csf_flow/

CSF is not a static fluid; it is continuously flowing back and forth between the head and the spine. The direction of flow is determined by the cardiac cycle. When the heart maximally contracts to pump blood out of its chambers and to the head and body (the systolic phase) the brain becomes engorged with blood, and as it temporarily swells up, ventricles filled with CSF are squeezed. This action pumps CSF downward towards the skull base and spine. Conversely, when the heart relaxes (the diastolic phase) blood fills the atria and the cerebral ventricles relax, which causes CSF flow to reverse its direction and the fluid flows upward from the upper spine and skull base, into the center of the brain again. Because of this cycling spinal fluid is pulsatile; its movement is determined by pulsation of the heart.

This image shows pulsation within the CSF:


http://en.wikipedia.org/wiki/Cerebrospinal_fluid

Does that looks as though it is dependent on Brownian Motion and tempearature or density gradients?

The paper you link to does not make a CASE for IBT improving CSF circulation because it is full of over-reasoned conclusions that ignore the clearly observable driving forces behind CSF circulation.

[Adrian]

The author does not consider the cooling and density changes that must take place where evaporation occurs, I.E. in the nasal passage and the rest of respiratory tract. Also consider the evaporation taking place from the eyes and skin. In trees for example 98% of all the water at the leaves evaporates, this means that the sap has been concentrated by the evaporation by the same amount. This gives us a denser sap at the top of the tree, just as the evaporation from the respiratory tract changes the density of the capillary blood that flows through the lungs.

This paragraph clearly illustrates a poor grasp of both animal and plant physiology.

1. The capillary blood in the lungs could have its density affected by evaporative cooling but this blood quickly returns to the heart where its densites will be quickly equalised with other blood through the pumping action of the heart and in the arterial flow to the body, hence this evaporative cooling would not affect the desnity of CSF differentially in different parts of the body.

2. Making up numbers as if they were fact does you no favours. At any moment in time 98% of the water entering a leaf is not leaving the leaf. Clearly, if the leaf is not wilting then water loss must be being balanced by water uptake. Leaves can lose 100% of their mass through evaporation in an hour but they do this without reducing in mass because at any moment in time water loss is equal to water uptake.

3. Evaporation from a leaf may affect the xylem density in the leaf, however it would increase the density at the top yet the xylem continues to flow from bottom to top so this does not support your theory that increased density necessarily causes a downward flow. The phloem (aka sap) density is affected by active transport of solutes (sugars) into and out of the phloem at all levels in the plant and consequent of osmosis of water into or out of the phloem rather than by evaporation from the leaves. Phloem has been experimentally demonstrated to be flowing in both directions at the same time within the same phloem vessel.

Plants do not make the case for IBT, particularly when the reasoning used would achieve a fail grade in a lower secondary school plant physiology module of a biology course.

[anban]

...why did I get an IM??? I'm just a "bitter" spinal cord injured person.

[Andrew K Fletcher]

I wrote to you privately to question where and why you placed your remark about breast milk. I knew you were taking the pee, so did a little digging and found that a small group of people were ridiculing another member and myself in the private members forum.

[cripwalk]

Andrew, a legit business would be happy to report their corporate name and address. Why have you not done so?

[anban]

I wrote to you privately to question where and why you placed your remark about breast milk. I knew you were taking the pee, so did a little digging and found that a small group of people were ridiculing another member and myself in the private members forum.

All I got was a link to the survey you did a while back. I question the validity of calling it anything else, since there were no real controls, it's admittedly subjective and it's not quantitative.

My remark in this thread was intentionally flippant. I don't think you'll be selling too many IBT's to SCI's as we pretty much think it's FOS.

[beatscookin]

Because it isn't easy to convince people to try sleeping on an angle. They tend to come up with all sorts of excuses not to try it rather than experimenting for themselves. Just like the majority of people posting on this thread.

Sounds more like all sorts of excuses for not doing a real scientific study. Anecdotal evidence is worth nothing!

[Andrew K Fletcher]

Tilting a bed to make use of gravity is something NASA have been doing since the early 90's. I would consider their opinion as being worthwhile, especially when they go to the trouble of publishing their conclusions and thoughts. Yes I know you are going to think of all sorts of excuses to ignore this research as much as you will ignore the effects that gravity has upon the circulation, which is your choice and I respect that. But using your bias and poor understanding of physiology to try to discourage people with spinal cord injury from considering that gravity and posture can help people with neurological conditions to regain function and sensation is deplorable. Nevertheless, I hope you enjoy watching the videos. There are more interesting videos on her channel.

Published on 19 Feb 2013
In this 2012 talk at NASA's Ames Research Center, Dr. Joan
Vernikos explains how during these technology-rich times we're moving (and using gravity) less and how that is slowly undermining our health.

http://www.youtube.com/watch?v=SnEpg1MOoKg

Published on 19 Feb 2013
Dr. Joan Vernikos visits NASA's Ames Research Center and tells the story of George Mueller, and how simply standing up frequently throughout the day helped this 91 year-old get back on his feet. http://www.joanvernikos.com

http://www.youtube.com/watch?v=qSoRmaNLoiw

Published on 18 Feb 2013
In this 2012 talk at NASA's Ames Research Center Dr Joan Vernikos, author of "Sitting Kills, Moving Heals", explains how what we've leaned form astronauts has shown that so many of the ills affecting our health today are due to not moving enough throughout the day.

http://www.youtube.com/watch?v=fglQLFCAVeY

Published on 19 Feb 2013
In this 2012 talk at NASA, Dr. Joan Vernikos explains how a lifestyle of frequent, low-intensity, non-exercise movement throughout the day is a great way to remain healthier.

http://www.youtube.com/watch?v=TKjr-az3xeE