Oh, Sugar! Paediatric Hypoglycaemia

Anyone who has ever worked in or maybe even visited an Emergency Department knows that we LOVE acronyms.  Students and trainees alike know that the answer to any “How would you manage this patient?” question in the ED must begin:

“Well, first I would check A-B-C…”

In the UK, we love acronyms so much in Emergency Medicine, we have given the three parts of the college membership exam letters corresponding to our favourite acronym (other colleges have, unimaginatively, used numbers).

 

What you might also be aware of, if you have worked in paediatrics, paed EM, attended any paediatric life support course or ever seen a paediatric patient, is the acronym D-E-F-G:

Don’t Ever Forget Glucose

Now, there are quite enough acronyms in clinical medicine and their use can definitely be confusing. But the point this one makes is valid: hypo- and hyperglycemia are great pretenders (much like syphilis), presenting with a variety of vague, seemingly disconnected symptoms, and checking a bedside glucose is a vital part of the assessment of the sick child.

Management of previously undiagnosed hyperglycemia is straightforward: whether or not there is ketoacidosis present, the child needs admission under the inpatient paediatric team.  But what of paediatric hypoglycaemia?  It’s not uncommon in children presenting with gastroenteritis, and is easily corrected.  Do these patients also require inpatient admission?

This is the question posed to me on Twitter by Brian Burns (@HawkmoonHEMS), an Emergency Physician and HEMS doctor:

This question is really important, not least because it highlights an important mental divide: if you ask a paediatrician and an EM doctor how they would manage hypoglycaemia, their answers will very likely be vastly different.  Should they be?

Hypoglycaemia

Beth Jameson, a fabulous registrar in paediatric metabolic disease at the Royal Manchester Children’s Hospital, gave a great presentation on metabolic disease to me and to my PICU colleagues. She sums up how she, as a paediatric specialist, would think about hypoglycaemia in this single slide.

Credit and thanks to Beth Jameson

The problem is that, as Emergency Physicians, we see hypoglycaemia reasonably often – usually in adult diabetic patients.  We give them some jam on toast, a cup of sugary tea and they feel better, so we send them on their way.  Can we take the same approach to paediatric patients?  Well, if they have known insulin-dependent diabetes, then this approach might also be reasonable.  A quick note or phone call to their diabetic specialist nurse is a useful safety net.

We also know how to treat life-threatening hypoglycaemia in obtunded patients; the latest (5th edition) APLS guidelines advocate 2ml/kg 10% dextrose followed by an intravenous infusion.

But let’s think about those patients who don’t have diabetes: can we send them home once their sugar responds, or do they all need investigation?

Neonates

As with almost everything to do with neonates, be suspicious, be scared and refer the neonate with hypoglycaemia.  Many of the nastiest metabolic diseases present in the neonatal period; there is no way that a hypoglycaemic neonate should be discharged from the Emergency Department.  Alarm bells should be totally deafening you if the child is an ex-prem, febrile, jaundiced or there is a history of consanguinity.  Obtain IV access and resuscitate the child, and correct the glucose as above (and if you can send an ammonia level the paediatricians will love you).  Get expert paediatric help early.

Known Metabolic Disease

If you are unlucky or happen to work near a centre for metabolic disease, you might meet patients with known underlying metabolic disease.  Many of these patients become hypoglycaemic with intercurrent illness.  They will often carry details of an “emergency regime” with them, or know where to access it.  In the UK, the British Inherited Metabolic Disease Group has a fantastic online Emergency Protocols resource, divided into children and adults and listed by disease. This should help you address the basics while you get expert input.

Beyond the Neonatal Period

Beyond the neonatal period, hypoglycaemia becomes more common.  Children typically have poor glycemic stores, lasting around 12 hours in young children and 4 hours in infants.  Most commonly, hypoglycaemia is seen in children with gastroenteritis.  A recent early publication suggests an association between rotavirus infection and hypoglycaemia, in addition to an association between only giving sugar-free fluids at home to maintain hydration.  Parents who bring their children to the Emergency Department with gastroenteritis frequently justify their attendance with a concern that the child is not eating.  It is certainly not uncommon for children to have a reduced appetite during acute illness (and to “not keep anything down” if they are given porridge immediately after their last vomit) and this need not be problematic as long as the child is offered sugar-containing juice, remains alert and has a good urine output.

The problem is, previously undiagnosed metabolic and endocrine disease can be precipitated out by intercurrent illness and can be diagnosed at any age.  How can we know in the Emergency Department whether the hypoglycaemia is due to rotaviral infection or underlying adrenal failure, or medium chain acyl dehydrogenase deficiency (MCADD)?  Unfortunately, we can’t.  We can, however, be sensible.   In my practice, I try to take a sensible approach.

 The Sick Child

I would normally refer to the inpatient team:

  • Any child who does not have a good history of infective gastroenteritis.  History is very important: remember particularly in toddlers the risk of accidental ingestion. Are there any medications in the house that the child might have been able to get hold of?  Think of grandma’s gliclazide and quinine here.
  • A child who appears unwell for any other reason.  I refer you back to my personal unpleasant experience of watching a purpuric rash develop on the back of a child admitted with diarrhoea and vomiting, being observed because of hypoglycaemia at presentation. Sepsis kills.
  • The child whom the parents are concerned about.  You know they will come back anyway if the child vomits again.  But parental concern is an important cue.  Take them seriously.
  • If the child does not respond to initial enteral correction of hypoglycaemia.
  • If you are inserting an intravenous cannula (and consider sending a hypoglycaemia screen – see below).

Observe

Children who present to the department with hypoglycaemia should have a hypoglycaemia screen while their sugar level is low. It is done while they are hypoglycaemic to give a “true” lab glucose and also for a meaningful ketone level, as ketosis can be helpful in identifying underlying disease. In practice, this means stabbing a child’s veins without topical anaesthesia and is sometimes impossible because by the time you are aware of the child’s hypoglycaemia, someone has kindly given them some glucose or some jam.

If there has been documented hypoglycaemia, now corrected, in the setting of gastroenteritis with no other concerns, the child might be able to go home after a period of observation.  It is really tricky to safely discharge these patients.  Gastroenteritis as the cause is, realistically, a diagnosis of exclusion.  I would certainly advocate admission to a paediatric observation ward if one is available, with topical local anaesthetic in situ so that a hypoglycaemia  screen can be performed if the sugar falls again.

The Hypoglycaemia Screen

This will probably vary from hospital-to-hospital, but here are the basic ingredients. Please also check your local policy (don’t blame me!)

Typical hypoglycaemia screen

 

So ALL these patients need to have a hypoglycaemia screen?

I think probably, yes – sorry :-) But I can’t see any way around it.  It’s important to make a diagnosis of underlying illness if one exists, and without performing a hypoglycaemia screen it’s difficult to be completely sure.

Better safe than sorry – and I don’t feel that brave today.

 

Further Reading

Diagnosis and Management of Hypoglycaemia Beyond the Neonatal Period – here

The Investigation and Management of Neonatal Hypoglycaemia – here

Make sure you also check out our disclaimer

 

Natalie May

 

Comments

    • Natalie May says

      Thanks for the feedback Gavin, glad you like the post! List of differentials huge – hypoglycaemia bad until proven otherwise?

  1. says

    Great post again – balancing the practical nature of the problem with the clear need to always ensure patient safety. Some additional points from someone who works at both ends as it were…

    In the case of the well child who has a much lower than expected BG just check the machine is calibrated correctly. One afternoon we had 5 <2mmol/L in one hour… statistically unlikely (although possible!) but all due to an out of date and dysfunctional analyser. They get used a lot so its not un-suprising accuracy changes over time.
    [and additional point is often if you run a gas off a capillary sample and put some of the blood in a BG dipstick you get results just under and above 3 which is quite annoying]

    It is often incredibly difficult to get all the samples. It is never 'simple' to do a blood glucose screen (and it often in the age group with large amounts of subcutaneous fat). Important to prioritise locally what are must haves.

    Mild hyperglycaemia is a stress response and may be a sign serious bacterial illness.

    An observational study is needed on un-investigated hypoglycaemia secondary to gastroenteritis to find out how many end up with any long term issues.

    Carry on the great work with these blogs!

    • Natalie May says

      Thanks for the reply Damian.
      I agree – be suspicious of your glucometer! Lab confirmation is essential if you are taking bloods (I agree, not often easy – know what you want in advance and get what you can).
      Also a good point about hyperglycaemia: stress response = steroid release = hyperglycaemia with intercurrent illness (which is why diabetics need more insulin and tend to run high when unwell). Even MORE reason to be suspicious of hypoglycaemia.
      Glad you like the blog!
      Nat

  2. says

    Fantastic stuff Nat. Encapsulates a lot of what is great and also rather scary about PEM!

    You know my opinion on neonates…..!

    I cannot endorse the BIMDG guidelines enough at http://www.bimdg.org.uk/protocols/disclaimer.asp. They have got me out of a sticky situation on more than one occasion and they are totally #FOAM and as far as I’m aware always have been.

    Amy asks me to remind everyone that Ammonia needs to go on ice….

    Super stuff……again!

    S

  3. says

    I shred your post with a colleague who is a joint EP/Paediatrician who had some interesting comments. He is however, a bit scared of technology and blogs, so wouldn’t put his comment up here himself. I though I’d take the plunge (with permission from him) and put it on for him (and I quote):

    “Does it say anything other than admit and extensively investigate every hypoglycaemic patient?

    It misses the opportunity of a good argument as to which patients you could investigate less and treat as an OP.

    Idiopathic ketotic hypoglycaemia is the condition to try and fit the kid into.

    If they do measure urine ketones, VBG (exclude lactate ++), +/- cortisol and GH, acyl carnitines for fatty acid disorders. Then give ‘em some sugar, watch them a few hrs and d/c with advice, provided parents are up for it.

    I’m not sure ammonia is amazingly useful in this context either. The main time to think of it is in kids presenting with ‘encephalopathy’ and is good to screen then.

    It may be a bit up in general liver probs (Reye etc) which also have hypoglycaemia. But I think it can also be normal in those conditions so may be over relied on as an excluder.

    Blog that and I would imagine there’d be a bit of chat generated” (Nick Watkins)

    • Natalie May says

      Valuable thoughts.
      There is a real challenge here, probably exacerbated by the UK’s 4 hour target in EDs and the fact that most departments seeing children do not have access to a unit where they can be admitted for longer observation without referral to an inpatient team.
      The reality is that it is likely that most of these kids are hypo from depletion of stores and insufficient intake rather than any sinister underlying pathology. The challenge – for us anyway – is determining which kids DO have something else going on. 
      Many will have a period of observation following enteral correction of hypoglycaemia during which they maintain their sugar level – so no hypoglycaemia screen is undertaken. We obviously aren’t going to keep these children in hospital forever. But how long is “enough”? 
      The answer isn’t clear, but I suspect it is more than four hours: as a parent (I am not one) I would be concerned about my child going to sleep without assurance that they could tolerate a period of starvation. 
      As Damian says, more research is needed to help us identify which kids we can send home. Maybe we should temporarily lend out glucometers the way we lend out crutches so longer observation can be undertaken at home..?
      Also, with the identification of more subtle genetic metabolic disorders there is doubt about whether idiopathic ketotic hypoglycaemia exists or simply represents a collection of as yet unidentified metabolic disorders. Whether we even need to identify them is the million dollar question.
      Lastly, the majority of clinicians accessing the blog are not Paeds EM specialists and many may be very junior. We also try to keep things safe and simple. Hypoglycaemia in kids can represent very serious illness and if a doc new to EM now recognises that then as far as I am concerned the blog has achieved an important goal :-)

  4. Christine says

    Something not mentioned (although hopefully rare) is the possibility of underfeeding, particularly in neonates due to the poor reserve. I’ve seen at least one case where there were recurrent episodes and this was the suspected cause after everything else had been ruled out. Unfortunately never found out the outcome.

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