Awesome summary of the really dynamic and weird state of fluid homeostasis.
There is so much understanding we get from knowing how the glycocalyx works – seems to answer a lot of long held questions and matches with recent quality data on resuscitation.

To use a metaphor – Resus without understanding the glycocalyx is like being a gastro doc who doesn’t get the intestinal brush border function.

I think we will learn a lot about crit care down this path of research

Nice description of what might be happening in septic patients. I think that we really don’t understand what’s going on in sepsis, and what is happening during one condition and at one time point and in a particular organ may not be occurring elsewhere. So blindly we go on… Regarding the glycocalyx – it appears to be of some importance – how much is unclear. Caveoli also may play a role with regards to endothelial permeability and like the glycocalyx their importance is unclear to me. I still think Starling forces are at play and whether the reflection coefficient is… Read more »

Grasp this…
http://bja.oxfordjournals.org/content/108/3/384.full.pdf+html
Colloids don’t work in low capillary pressure states because Jv is close to zero and delta pi (oncotic pressure gradient opposing filtration) will be increased even by crystalloid resuscitation, added colloid is unnecessary. Hyperoncotic solution boluses suck water out of the glycocalyx if it isn’t already flat as a pancake and should not be given to hypovolaemic patients. Now lets talk about the J-curve and the J-point.
Declaration of interest… my son & I wrote it.

Holy C^%#@%$#!!!!!!!

Back to the drawing board…awesome!

Always gotta be ready to re-examine your thinking!

Great post, Scott!

Fantastic article, Tom W……very nicely put indeed. Like I mentioned in our previous correspondence, the RSE&GM concept helps to very nicely put a lot of our clinical experiences in context. What people need to realise is that the cellular compartment, which is where life as we know happens, depends on extravasation of Oxygen and nutrients from the intravascular space into the interstitial space from where they get into the cellular compartment along electrochemical or physical gradients. In trying to chase an arbitrary MAP number, our desperate attempt to keep all the fluid in the intravascular space by perhaps synthetic colloids… Read more »

Great article, thanks Scott!

Who says noradrenaline doesn’t clamp down on the lymphatic system as well? It does seem to make sense – to maintain any kind of prolonged fight/flight response we’d need to balance the increased intravascular pressure with lymphatic pressure so we don’t extravasate all our blood volume before the chase is over… Perhaps lymphatic pressure is the missing piece in the MAP puzzle. So then… antibiotics & noradrenalin as an empiric package for severe sepsis? Is anyone doing this?

I just had a stroke reading this.

Positive pressure ventilation raises RAP, to some extent, and therefore MSFP (for a given cardiac output). How much does a change in MSFP impact upon capillary hydrostatic pressure? It may be insignificant but I can’t find anything about it.