Clinical Case 116: FEAST or Flush Fluids

Today’s case is about the Resus of severely dry children – very typical of Broome.  But before we get to the case – here is a bit of a review of some recent learning I have had on the topic.   I have started to rethink the traditional acute fluid resuscitation management of these kids.  The FEAST trial was published 4 years ago now.  IN a nutshell it showed that giving IV fluid boluses to sick kids was harmful – lead to higher mortality.  It was one of those trials that, if nothing else, should make us rethink our practice.  Kids with severe dehydration due to diarrheal illness were NOT included in the study, so we cannot really apply it directly to the following case. However, it certainly does make me wonder…

At SMACC in Chicago recently there was an awesome panel discussion by world leaders in fluids / sepsis management.  Dr Kathryn Maitland [lead author of FEAST] was on the stage and answered some tough questions about the role of fluids in extremely sick kids.  The mechanism by which the kids in the “bolus fluid” arm died was discussed.  The children in the “bolus” group seemed to suffer an acute cardiovascular collapse more often than the “no bolus” cohort.  Why is this?  There were a few ideas postulated.  The one that made the most sense to me is that we just might be pushing the pH over the brink of life when using bolus fluids.  But there were a few other mechanisms invoked by the brains trust also.

So anyone who has ever done the APLS or other Paeds Resus course will tell you that the treatment for severe shock is a 10 – 20 ml/kg bolus of IV (or IO) 0.9% saline.  We expect our Med Students to have this number in the front of their mind – it is the “hammer” for all Paeds Resus “Nails”.  However, if you follow the blog or are a fan of the excellent Emcrit series on acid-base therapy then you will know that “normal” SALINE is in fact a nett acidotic fluid which will raise the chloride level [narrow ones’ SID] and force your body to retain H+ ions.  Now this doesn’t matter so much in kids whom are fasting for a theatre case or otherwise well.  However if you are in a scenario where your little patient is sailing very close to the edge of biochemical disaster then a big slug of unbalanced NaCl may just be the thing that pushes them over the egde.  Do we have any direct evidence for this?  No, none that I know of. IV Therapy helps prevent illness, treat acute or chronic health conditions or bring you back to your vibrant self.

Severe dehydration with hypovolemia and malperfusion certainly needs aggressive treatment – we have to try and restore volume / flow and pull them back from multiorgan dysfunction.  So giving fluids seems like a good idea.  But how much, how fast and which fluid to use is certainly a question that I think remains unanswered. Dr John Myburgh gave a great lecture on the ICN series on the history and current state of resuscitation fluids HERE.   My favourite line from his talk was from Dr Malcolm Wilson: “I don’t care if you use dog’s piss, as long as you use it carefully.”  Very Aussie!  But the principle is important – when dealing with really sick kids and fluid Resus – you have to think it through and reassess frequently, proceed with caution.  Fluids are ‘drugs’ just like antibiotics etc.   We need to prescribe the right stuff for the patient in front of us.

So here is the case:

JJ is a 4 month old boy whom has had a diarrheal illness for 5 days.  He has been lethargic and had a few vomits today.  His parents noticed he has been “breathing fast” all afternoon and now at midnght presents with a low-grade fever, diarrhea and lethargy / somnolence.  He is refusing to feed.

Back ground history: born at 36 weeks with IUGR  LBW = 2100g.

Breastfed and has received 1 round of infant immunisations.  Was doing well and putting on weight.  He was weighed in the clinic last week at 4000 g…   but tonight he is weighing in at 3500 g [not good!]

At triage his Obs :  Temp  = 37.3  HR 200, sluggish central cap refill, RR 55/min. He has no recession / tug.  His feet are cooler than his legs

His belly feels soft with hyperactive bowel sounds.  The chest is clear [to Ultrasound!]  The bladder is empty.

This is all consistent with Gastro.  A 500 gram weight loss in this kid equates to about 12% i.e. severe end of the spectrum.

This kid is very sick – we need to know what is going on with his electrolytes / acid:base and renal function.

Luckily an IVC is able to be placed and bloods drawn.  Here is the VBG:

pH = 7.10,   pCO2 = 17    HCO3-= 6.1   BE =  -23.1   Lactate = 3.3

Na = 156  Cl = 128  K+ = 5.1    Creat = 99      The CRP is as always…. 42!

OK…  lets hit the pause button there.  A few questions.

Q1:  Does JJ require a fluid bolus?

Q2: Which fluid and what volume would you give IV in the first instance?

Q3: Assuming he need ongoing fluid replacement – what are you going to prescribe over the coming hours?