Preprint cerebral blood flow relation is abnormal in most ME/CFS patients with a normal heart rate and blood pressure response, 2024, van Campen et al

I just want to mention that based on my personal experience (very severe OI), knee-high compression socks (class II, 23-32 mmHg) is enough to make a noticeable and useful difference, measurable by the blood pressure monitor as well. Thigh-highs are more effective, but the knee-highs really do help enough to be of actual use.

I have tried high-waisted compression tights too, as well as regular firm control "shapewear" for example very high-waisted shorts. Personally I find all these a bit too uncomfortable and restricting to wear on a daily basis. In my case they haven't made much of a difference compared to the thigh-highs.

@Jonathan Edwards Sorry if you find my repeated comments on this topic annoying

 

Perhaps salt water has a longer lasting effect than predicted for this reason:

My orthostatic symptoms are dependent on how long I've been upright and the type of stressor. Sitting is better than standing but worse than lying down. Riding a bike is better than walking. Standing is worse than walking. The worst thing is repeatedly alternating between squatting and standing.

The stress caused by this accumulates over the course of the day. Drinking salt water, even just once, may lead to a lower overall stress level at the end of the day even if by then blood volume is not different.

The best thing is to repeatedly drink salt water.

 

Yes, things may be pretty complicated over a longer period of say hours. And it may vary from person to person depending on whether they have a tendency to develop oedema, like my left leg and maybe @mango?, or maybe widened calf veins.

So it would be useful to have some proper measurements from a study.

 

Salt helps my OI, too, and generally makes me feel less unwell. I used to add a bit to food, till I stayed with someone who didn't use salt in their cooking and realised my muscles weren't on fire any more. It's so painful that OI's the lesser evil.

Next best is leg compression. It doesn't resolve the low-grade headache as completely as salt, but it does improve it—when the weather's cooled down enough to wear compression garments again, my head clears within seconds. It's one of those grumbling background things that's most obvious when it stops.

 

Why not start with a trial to measure blood volume ? Was this ever discussed at the research working group @Jonathan Edwards

 

No it wasn't, but I think measuring blood volume is not that simple. It also isn't necessarily what we really want to know - which is perfusion flow in specific organs. The relation to volume may be complicated.

 

It doesn't seem to be used outside of Russia and other post-Soviet states, but within Russia, emoxypine is touted as increasing cerebral blood flow, treating endothelial dysfunction of some type, reducing oxidative stress, increasing ATP, among other things.

I have no stake in those particular claims and my Russian isn't good enough to make much sense of the academic publications on it, but I do wish someone would look into it, even if only to confirm it's overstated or irrelevant to ME/CFS.

 

Here’s a couple of studies on compression garments that might be of interest:

Compression Stockings Improve Cardiac Output and Cerebral Blood Flow during Tilt Testing in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) Patients: A Randomized Crossover Trial

Compression Garment Reduces Orthostatic Tachycardia and Symptoms in Patients With Postural Orthostatic Tachycardia Syndrome

The colourful illustrations (Figure 2) in the second paper always amuse me, for unknown reasons.

On a tangent, scientists have used a negative pressure vessel, a bit like an iron lung, to induce blood pooling in the lower body. I think Dr Blair Grubb discusses it in some of his lectures. He tried it out and described the experience as unpleasant.

On another tangent, this enterprising patient obtained a second-hand military g-suit to combat her blood pooling:
https://oiresource.com/pictures.htm

 

On measuring blood volume:

There is a recently accredited medical device that can measure total blood volume quickly and easily:
https://detalo-health.com/

It uses carbon monoxide rebreathing (a tiny amount) as a tracer.

It is not a new method, but the ability to purchase it as an EU-accredited medical device is new as of 2023. It is much cheaper to purchase and operate than the older nuclear medicine technology.


There is also apparently a new and easy way to measure splanchnic (abdominal) blood pooling.

It’s mentioned in this clinical trial looking at post-prandial symptoms in POTS but I can’t find any further info on it:

Splanchnic Venous Capacitance in Postural Tachycardia Syndrome

“… an innovative technique to assess venous capacitance in humans, using segmental impedance to measure the effect of graded positive airway pressure (CPAP) on splanchnic blood volume.”

I tried emailing the lead researcher but I don’t think I got a reply.

 

Nimodipine (calcium channel blocker) has been thought to increase cerebral blood flow by being selective for dilating cerebral blood vessels.

However, there has been further research in recent years questioning whether it is as selective as previously thought.

Also, it will lower blood pressure, so would be contraindicated for anyone with low blood pressure, and test subjects with normal blood pressure would have to be monitored.

(My daughter is currently trying nimodipine to see whether it is more effective than her previous regime of amlodipine and candesartan. She has abnormal cerebral vasoconstriction and mild hypertension that seems to be co-morbid.)

 

Dr Satish Raj (and others) found abnormalities in the renin–angiotensin–aldosterone system (RAAS) in POTS patients. It has been called the renin–aldosterone paradox.

https://www.ahajournals.org/doi/10.1161/01.CIR.0000160356.97313.5D?url_ver=Z39.88-2003&rfr_id=ori:rid:crossref.org&rfr_dat=cr_pub 0pubmed

The RAAS regulates blood volume.

I think RAAS abnormalities have also been found in ME/CFS patients.

The possible mechanism for IV saline working better than consuming water and salt is that the IV saline bypasses the RAAS, and it takes it a while to catch up and reset the body to the abnormal low level of blood volume that it mistakenly targets.

Hence the person receiving the IV fluids experiences a period of increased blood volume and improved symptoms that dissipates over perhaps a few days.

As always, more research is needed. It’s an interesting angle and I hope some new researchers take another look at it.

Dr Raj has given a lecture on this topic:
Understanding Blood Volume & Hemodynamics in POTS