So something has been trotting around my head for a few months, and it actually stems from a small and not-so-proud moment I experienced during a conversation with my wife, while she was still a resident.
She was telling me some of the stories of the day, and how one of her supervisors who had a mixed outpatient and ED practice, always pushed them to use PO fluids, get rid of IVs and get the patients home. I kind of scoffed, in a sadly typical acute care physician mode, saying how you had to be a bit more aggressive and give them IV fluids to revert their dehydration a bit faster.
Then I caught myself. Hmmm. What exactly am I saying this (con brio) on the basis of. Knowledge, or belief? I tried to find knowledge but came up woefully short. It seems I’m doing this out of habit, what I’ve seen/learned/believed in the two decades since someone handed me an MD degree. Damn.
So, I do believe in evolution. We have evolved platelets to stop bleeding, fibroblasts and osteoblasts that can fix bones, white cells that go mop up the messes, and all kinds of other good stuff. One thing we do NOT have is small openings in vascular structures that allow unprocessed, man-made fluids directly into the bloodstream. We make these. We insert tubing into normally sterile environment and infuse a vast number of medications directly into this fragile matrix of cells and organic colloid – with the best of intentions.
In our physiology, however, the ONLY way fluid ever enters the vascular spaces is by diffusion from the outside of the endothelial cell into the lumen, molecule by molecule and ion by ion.
So let me seemingly diverge for a bit…
Prior to the 1970’s, restricting oral intake was a “cornerstone” therapy of diarrheal illness, due to the pervasive belief that the GI tract needed time to heal and recover before resuming normal function. This was felt to be crucial. Hence, only IV therapy was used (in developed countries), and in the underdeveloped world, the death toll was appalling – especially among children. In the 40’s, Dr. Darrow of Yale started actually studying the GI tract fluid and electrolyte issue, and advocating oral rehydration with mixed fluids. He was able to bring infant mortality radically down in his practice, but it would take over twenty years before a groups started to formally look at this in the 60’s. Finally, in the late 70’s, the WHO pushed this out into the field, and the childhood worldwide mortality from acute diarrheal illness dropped by over 70%, from over 5 million deaths a year to a bit over 1 million – at that time.
Oral Rehydration Therapy (ORT) is now felt to be one of the most significant advances in modern medicine. Compared to that impact, all the critical care and cardiology trials are about as significant as a drop in a bucket. We’re not talking about composite end points and subgroup odds ratios of 0.85…
For a great review on this check out The History of Oral Rehydration Therapy by Joshua Nalibow Ruxin (google it). A great story of science and humanity, good and bad.
So, back to 2015 ED/ICU’s.
The question now becomes the following: why – in the presence of a functional gut – do I choose to entirely rely on non-physiological IV fluid resuscitation?
I can already hear the roars and the outrage and the cries of heresy. And heresy is certainly what this is (Heresy is any provocative belief or theory that is strongly at variance with established beliefs or customs – Wikipedia). But that doesn’t make it wrong.
So I would ask everyone – particularly the naysayers, to examine their knowledge and see if they actually have any at all that supports the strong conviction that IV fluids are the way to go in ALL cases (my N=1 principle precludes going for the one-size-fits-all therapeutic approach).
Now everyone agrees that, once patients are better, they should be on feeds with little maintenance fluids. I don’t think many will debate that. So that should be the basis to wonder whether, in the presence of a functional gut, a variable proportion of fluid resuscitation in acute illness should be enteral…
I’ll let everyone digest that.
Comments more than welcome.
More to come in Part 2.