Tuesday, 23 October 2018

The Practicalities of Croup Management in the Community

This post is in response to a very specific question from a local GP. The question wasn't about recognising croup or even about the best evidence based treatment.  Recognising croup is fairly straightforward. There is pretty much consensus on the best management of croup. The question was about the practicalities.

The evidence for the ideal management of croup has given us a fairly straightforward and reasonably robust answer: a single 0.15mg/kg dose of oral dexamethasone.  Sounds simple doesn't it?  The difficulty is that a single dose is actually quite problematic from a pharmacy point of view. As a result the decision isn't always about the best available evidence.  It might also be about the best available medication and formulation.  To determine the answer to this question, we need to go back a couple of steps.

Croup is a clinical presentation involving barking cough, with or without stridor and respiratory distress.  This usually occurs in a relatively well child, though they will have the symptoms of a viral upper respiratory tract infection.  Like so many presentations in childhood, the underlying cause is a viral illness but the problem is due to the effect or response to the virus.  In the case of croup, that effect is upper airway inflammation and swelling.

When should croup be treated?
Croup is usually classified into mild, moderate or severe.  This can be done with or without a croup score.  While it is a minor oversimplification of what happens next, the likelihood is that severe croup will be treated with steroids and often admitted to hospital while moderate croup will usually be treated with steroids and discharged home after a period of observation.

It is the management of mild croup which often generates the most discussion.  The first question is whether it should be treated at all.  There is evidence that treating mild croup with corticosteroids (1) reduces symptoms.  There is the suggestion that it is safer to treat mild croup in that there is a reduction in time spent in hospital and reduced readmission rate for those that are treated.  However there is no specific evidence that not treating mild croup leads to an increased risk of severe or life threatening croup.  This leads some clinicians to the conclusion that if a child has a barking cough but no stridor or respiratory distress, they prefer to provide safety-netting advice and reassess if the child develops new signs.

How should croup be treated?
There is also evidence regarding the most effective steroid treatment for croup in children.  Oral dexamethasone outperforms oral prednisolone.  Both oral treatments outperform nebulised budesonide.  The suspicion is that dexamethasone outperforms prednisolone because it is better tolerated.  It's difficult for a medication to be effective if it's just been puked onto the floor.

If that's all so well evidence based, what's the problem?  Lets's get on with giving them all dexamethasone 0.15mg/kg. The problem with this is that is that dexamethasone liquid has done itself out of a job.

Dexamethasone is given as a single dose in the vast majority of cases.  The evidence shows that this works well, quickly (2) and with an effect which is sustained over several days.  It is quite potent, so small doses are effective.  These factors, combined with an unpredictable demand and a relatively short shelf life make dexamethasone liquid something that doesn't make business sense for pharmacies to stock.

I recently asked the twitter community about what they had available and while many did have dexamethasone liquid, it certainly wasn't routinely available.  The question also sparked a smattering of stories from people who had been sent from place to place looking for one that had some dexamethasone available.

This then presents a dilemma for the clinician in the community.  Do you prescribe the best tolerated and most effective treatment and take the risk that it will be unavailable?  Do you prescribe an alternative (soluble prednisolone) that is known to be slightly less effective and less well tolerated on the grounds that a medication can only be effective if it's actually been given?

There is also an opportunity to be proactive about the issue.  You could get a member of your team to contact the local pharmacies and ask if any of them do stock liquid dexamethasone.  If not, perhaps one would in which case they would be where you sent your children with croup for their treatment.

On a larger scale, primary care groups (e.g. Clinical commissioning groups in the UK) could coordinate something so that each locality has a pharmacy that stocks liquid dexamethasone.

Another way of looking at it is that there is a vicious cycle to break.  Because dexamethasone is not always available, not everyone provides it.  Because it is not prescribed often enough, it is not always stocked by pharmacists.  More prescribing of dexamethasone should make it more likely that dexamethasone will be stocked.

It is possible that liquid dexamethasone will become a more commonly prescribed medication since it has recently been suggested that it is as effective as prednisolone for childhood wheeze. (3)

What about age banding and using soluble dexamethasone?

Dexamethasone has a large therapeutic window.  The current recommended dose of 0.15mg/kg is a quarter of the dose of 0.6mg/kg which was previously the most often used dose.

This is good because age banding doses is very difficult.  A four year old can be anything from 13-22kg based on the 9th-91st centiles of the WHO growth charts.  Knowing the age is therefore nowhere near as good as having an actual weight.  Obtaining a child's weight does not require any special equipment.  If a child will not stand on a set of scales, simply weigh an adult carrying the child and without holding the child.  The difference is the child's weight.

If using Using the 9th-91st weight centiles and aiming for a dose of 0.15-0.3mg/kg gives the following results:

The ideal is definitely to have a weight and to have a liquid suspension available that would allow the precise dose of 0.15mg/kg to be given.  However, when thinking about a plan B, it seems a shame to go to Prednisolone which is known to be less effective, has more side effects and can only be given in aliquots of 5mg.  Why not do the same with dexamethasone, even if it does mean that the dose may be over in some cases?  Again, the therapeutic window of dexamethasone allows this to be possible.

Although liquid dexamethasone is not always on the shelves of the local pharmacy, it probably should be and possibly would be if it was more often used and the pharmacist knew that the bottle would get used.

Edward Snelson
Pharmacoeconomist of the year 2020

Disclaimer - If treatments are better but do not make sense financially, children should have to pay for that themselves.  If necessary, there are some coal mines near me that could be reopened, giving the children an opportunity to earn the money to pay for all the wasted dexamethasone that they are responsible for.


Wednesday, 3 October 2018

Don’t say, "Eat healthily." Say. "Eat differently."

It’s highly likely that at some point you have had a conversation with a parent or child about the dietary changes that a child needs to make if they have constipation.  This discussion is fraught with difficulties.  Hands up if you’ve ever heard any of the following:
  • My child eats healthily.
  • Are you saying that I don’t give my child healthy food?
  • I can’t make him eat anything?
  • My child is just a fussy eater.
Sometimes it feels like we are pushing water uphill when we’re trying to explain the importance of diet and fluid intake.  The NICE guidelines for management of childhood constipation (1) de-emphasised the dietary part of resolving the problem.  That is not because diet is unimportant.  It is because dietary changes alone are not seen to be adequate and it is necessary to return normality through the use of macrogol laxatives.  When I ask people why they think constipation is so common in children, they often say that it is because children eat badly.  That may be a factor but the main reason that children become constipated is because they are children.  They have poor visceral awareness, no understanding of what their stools and bowel habit should be, and their behavioural response to the problem worsens the situation.  “It hurts when I poo.  I know, I’ll stop pooing!”

Although macrogol laxatives may be an essential part of the solution, dietary change is still important since management of idiopathic childhood constipation is a game of two halves.

So, why is it so difficult to address the lifestyle changes that are so key to success?  There are several reasons.

The first issue is to do with what is normal.  Parents and children alike only have themselves and those close to them as a reference for what is normal.  It’s hardly an ideal sample, especially when by definition at least one of the people in the reference set has constipation.  Similarly, they will look around themselves when asking themselves what is a normal diet.  As a comparison, ask yourself “What is the normal number of cars for a family of five to have?”  If you look at the globally statistical answer, the answer is zero cars.  Most of us would think about the families in our street or social sphere, not considering the bigger picture.

That’s fine though, because we’re not asking people to feed their child normally, we’re asking them to give their child a healthy diet.  That’s right isn’t it?  It’s technically true, but I think that practically and socially, it is the wrong message.

This is because the second difficulty is that the diet discussion is liable to provoke negative feelings.  As soon as you talk about healthy eating, people become defensive.  They may not vocalise it but that is how they are likely to feel.  There are really only two possibilities.  The first possibility is that they believe that the diet offered to the child is already healthy enough.  The message that the child's diet is not healthy is likely to be perceived as critical, which in turn will sabotage the impact of the message.  The second possibility is that they already know that they are giving an unhealthy diet to the child.  Talking about healthy eating is probably going to ignite feeling of guilt and inadequacy, also getting in the way of the ability to move forward.

Getting the language that we use in this important part of the consultation has the potential to radically alter patient and parent buy-in to what you are recommending.  I would suggest that you try changing just one word.  Instead of talking about eating healthily, talk about eating differently.  I usually explain that no matter what a child’s diet is like, there are always changes that can be made that will help them stay free of constipation.  Let’s think about what changes you could make, since constipation is such a horrible problem that every change that has an effect is great progress.

Here are some things that you could look at with the next constipated child you see:

Achievable changes
  • Cutting out sugary drinks
  • Reducing sweet snacks and starchy snacks (chips and crisps)
Easy wins
  • Change breakfast cereal to something high fibre
  • Ask school to allow a water bottle at all times and a permissive approach to toilet access
Practical tips
  • Don't use sweet and starchy snacks as a reward or treat, even for eating healthy food
  • Don't have the constipation food in the house at all. Instead have fruit out and permanently available
  • Give parents permission to not feed the child. If the child has been offered a healthy meal and they refuse it, don't offer them an alternative. Take the food away and let them know that they can have it back if they change their mind.
  • Tell the family that everyone finds it hard to make changes.  Because constipation is a long term problem, every small change can have a big effect.
Prescribing the laxative is the easy part. Making changes that will have a long term effect is much harder.  It's important that the family understands that we know how challenging it is.  It's also important that they know that we are not asking them to change from unhealthy to healthy.  Diet is not binary. What we do need is positive change.  It's time for the child to eat differently.

Edward Snelson
Definitely different

Disclaimer: I have to admit that my kids never got a second crack at their food because I always ate it if they wouldn't.  I'm sure that's fine.  It is fine isn't it?

  1. Constipation in children and young people: diagnosis and management, [CG99]. NICE, 2017