Wednesday, 8 January 2020

Something or nothing - why topical antibiotics are not for neonates with eye and umbilical infections

Newborn babies cause clinicians a lot of anxiety.  The worry about infections can lead to the use of antibiotics "just to be safe."  This is usually not the best approach.  Most of the time, the symptoms are nothing, and when they are something more significant, sending the baby home with topical antibiotics is not the solution.

Let's look at two common scenarios.

Scenario 1 - The baby with a sticky eye

A one week old presents with a unilateral sticky eye.  The baby is otherwise well, feeding and growing.   The left eye has a yellow discharge around the margin of the eyelid.  The baby's examination is otherwise normal.

What's the problem?  Something or nothing.

The nothing problem is the more common scenario.  Many babies are born with a non-patent nasolacrimal duct.  The inability to drain tears from the eye to the nose leads to the sticky eye.  Tears are made up mainly of water and lipid (for lubrication).  The water mostly evaporates leading to a thick secretion which accumulates.  This is not a sign of an infection.

Most blocked tear ducts will self-resolve over weeks or months.  It is unusual for them to persist until the infant's first birthday.  If it does, an ophthalmologist can unblock the duct with a probe.

Rarely, there will be a cystic collection in the tear duct.  This presents with the same sticky eye but with a swelling visible at the inner canthus of the eye.  There are some good pictures of what that looks like here.  Although these do sometimes self resolve, dacrocystoceles can be problematic and should be referred to an ophthalmologist.

The something problem is infective conjunctivitis, but not as you know it in older children.  Babies have all those lovely maternal antibodies to protect them from common viral infections, so viral conjunctivitis is relatively rare in newborns.  In addition to the increased likelihood of bacterial infections, there are two other factors that make topical antibiotics a bad idea for newborn eye infections.

Firstly, the infection may be congenitally acquired.  Chlamydia and gonorrhoea are two organisms that cause bacterial eye infections in neonates.

Secondly, the baby's immune system is heavily reliant on the aforementioned maternal antibodies.  Their own immune system is immature and relatively unresponsive.  That is one reason why newborns have vague symptoms during serious bacterial infections, while a one year old has a temperature of 39C and can look really unwell with an uncomplicated viral illness.

If this baby does have a bacterial eye infection, it is high risk both for the eye and the baby.
Opthalmia Neonatorum - from the Centers for Disease Control and Prevention's Public Health Image Library #3766

As a result of all of these factors, eye infections in newborns (ophthalmia neonatorum) should be taken seriously and referred for acute assessement and management by paediatrics or ophthalmology depending on your local pathways.

How do I tell the difference between the something and the nothing?

It's actually quite simple.  There are a few quick things to check:
The answers to these questions give you the answer to what you should do next.
While it might feel like the safe option to just give topical antibiotics to every baby with a sticky eye, this is not the case.  If the problem is a blocked tear duct, the eye drops may cause a chemical conjunctivitis and make things worse.  If the problem is an infection, it is higher risk for the eye and the baby and so needs careful assessment and management.

Scenario 2 - The baby with red skin around the umbilical stump

A three day old baby is brought to you by one of their parents.  There is some redness around the umbilical stump.

What is the problem?  Something or nothing.

The nothing option if the umbilical stump is still attached is non-infective inflammation.  From the moment of birth, the umbilical stump is devitalised tissue.  In the absence of a blood supply, it goes through a process that leads to separation, usually about a week or two after birth.  During this time it can either just become dry and shrivelled or it can become a bit sticky and smelly.  Often, the skin around the base has been repeatedly cleaned to remove any stickiness.  This itself can cause a small halo of red skin.
Image taken from the Stanford Newborn Nursery site and used with permission. This material was compiled by Janelle Aby, MD for educational purposes only.  Reproduction for commercial purposes is prohibited.  Utilisation of the materials for educating those who care for newborns is permitted with proper citation of source.
The nothing option if the umbilical stump has separated is an umbilical granuloma.  These benign growths are quite common and will self resolve.  They have a tendency to produce some exudate.  Again, repeated cleaning can cause a bit of inflammation to the surrounding skin.

The something scenario is omphalitis.  Infection of the umbilical stump carries a high risk of invasive infection.  This of course is partly due to the immunology of a newborn (see above).  It is also because the umbilicus retains its connection to the circulation.  The external part may be dead but the vessels inside are still patent and may help to seed the infection systemically.
Image taken from the Stanford Newborn Nursery site and used with permission. This material was compiled by Janelle Aby, MD for educational purposes only.  Reproduction for commercial purposes is prohibited.  Utilisation of the materials for educating those who care for newborns is permitted with proper citation of source.
Omphalitis is now a rare occurrence in the UK and other similar counties.  It remains a more frequent presentation in countries with limited healthcare resources, especially where it is common to give birth in unclean environments.
Since most of these neonates will be cared for in a hospital setting, babies that present to GP or ED are likely to be low risk.

In a low risk baby, the decision about what to do is fairly straightforward.
While it might feel like the safe option to just give topical antibiotics to every baby with a sticky umbilicus, this is not the case.  If the problem is non-infective inflamed skin, applying chemicals is only likely to make that worse.  Inflamed and broken skin does not make a good barrier to infection.  If the problem is an infection, it is a high risk situation best managed in a secondary care setting.

So if it's nothing, leave it alone.  This of course always requires good safetynetting advice.  If it is something significant, this is usually best managed in a secondary care setting.  There's no real role for the practice of doing something to make us feel like we've done something.

Edward Snelson
Cautious binarian
@sailordoctor



Sunday, 24 November 2019

Paediatric Warning Scores - why they are always right but never the answer

This decade has seen a massive rise in the use of early warning scores.  For many clinicians early warning scores are a thing with which they are well familiar.  For those who were in practice before early warning scores became commonplace, they can confusing. For those wondering what the place of these scores is, it is important to be clear about what they are and what they do.
What is a Paediatric Early Warning Score and which is the best?

Paediatric early warning scores are ways of flagging patients up for further assessment and guiding the urgency of that assessment.

The original paediatric early warning score is called PEWS and exists in many forms.  It tends to be chart based and was designed for monitoring of inpatients.  The idea behind it was to take a traditional observation chart and give thresholds for concern and action to the numbers being measured.  The reason for doing this was an awareness that sometimes observations were recorded but that deterioration or severity of illness was not acted upon.

PEWS charts have colours to show how deranged the numbers are.  Anything not in the green is used either as a threshold in its own right (i.e. a red parameter for one physiological variable has a required action) or is part of a score (i.e. added to the values of other parameters) or both.
Because children have differing physiology* at different ages and because each clinical environment is different, it is essential to use a PEWS chart that is appropriate to the child and for the actions to be appropriate to the place where it is used.

Although PEWS was designed for ongoing inpatient monitoring, it has been used in other environments including primary care community settings such as out-of-hours care providers.
A relatively new kid on the block is the Paediatric Observation Priority (POPS) score.  This scoring system includes a score for nurse/clinician gut feeling and a somewhat subjective score for breathing, making it an interesting blend of measured parameters and clinical judgement.
The other big difference with POPS is that it was designed for use in the front end of an Emergency Department.  Essentially, it was crafted to identify those patients who were more likely to need early senior decision making and early investigation or treatment.

Because it is not an ongoing observation chart, it can all cleverly fit on one page which has the numerical values* for each age.  For all of these reasons, POPS is increasingly used in community settings as a front door assessment tool.

*Note the careful avoidance of the word normal when referring to physiological parameters in children.  There is no normal, just numbers.

I wouldn't say that any one is better than another.  They have different usability and different emphasis.  What works best will vary by people and place of use.

Where a snapshot assessment is needed for high volumes of patients, I find that POPS works well.

What does the score mean?

The obtuse answer to that is, "A warning score in itself is not an answer."  The score was never designed to be an answer.  Instead it is part of a process that asks questions.  A score is simply a way of assigning a numerical value to a set number of variables.  It standardises a snapshot but in no way replaces appropriate clinical judgement.

The questions that are being asked are:
  • Is this child seriously unwell?
  • Who should be assessing this child?
  • Is the assessment time critical?
Of course these are questions that have always existed before scores were invented.  So if the score just asks the obvious questions, what is the point in them?

If the score is high but I am happy with the patient, does the score prove I am wrong?

No.  Let's prove that with an example.

Scenario 1 -
You go to see a child who has a POPS score of 5...
When you look at the breakdown of how they got  that score, they are a wheezy 3 year old with slight increased work of breathing (+1), a heart rate of 160 (+1), respiratory rate of 24 (+1), and Temp of 38 (+1). They were born prematurely at 32 weeks (+1) but have no ongoing complications of this.
When you go to see them, they run past you shouting, "I'm Spiderman!"
You complete your assessment and conclude that they have an uncomplicated viral URTI with a moderate viral wheeze.  It responds really well to salbutamol.
Four hour later they are tucked in bed at home with no respiratory distress.

Scenario 2 -
You go to see a child who has a POPS score of 5...
When you look at the breakdown of how this unwell 6 month old got  that score, they have a temperature of 37.9, heart rate is 176 (+1), a respiratory rate of 40 and they are grunting (+1).  They are subdued but if someone makes a noise the child produces a weak cry (+1).  They look seriously ill and the person completing the initial POPS score gave them 2 points for gut feel (+2).
Completing you assessment you decide that they are probably septic and act accordingly. Within 4 hours they are on a paediatric critical care unit, ventilated and on inotropes.  Two weeks later they leave hospital and make a full recovery.

The score indicated a need for an early and expert decision to be made.  In the case of scenario 1, the decision that the child was essentially well was entirely valid.  The score was valid also.

A score which is made up of these parameters cannot be wrong.  It is just a score.

Should I be using POPS scores in my clinical practice?

That depends on what you are using the score for.  If the score is to identify which of several children need to be put in front of a senior decision maker and how quickly that needs to happen, then that is a good use of a POPS score.  If the score is intended to identify a possible deterioration of a patient who is being monitored and observed, then this is what PEWS was designed for, though some will use POPS in that scenario.

If you have already made a clinical decision about the best course of action, then what do you want a score for?  After all, the score is simply a volume control for a question.  If you have already decided what the answer is, what is the score for?

Edward Snelson
Qualitative quantifier
@sailordoctor
Comment from Dr Damian Roland - Consultant in PEM at Leicester Royal Infirmary and one of the original developers of the POPS score:

Many thanks Edward - great piece and love the volume analogy! I use a very similar example of two different patients with the same score and what this means. It's an important example as children with higher scores (if admitted) have longer length of stay (based on the initial assessment POPS). A child with a score of 5 and above if admitted is likely to be in hospital for over 24 hours and also has a slightly higher risk of return if discharged (but the latter association actually quite weak). But lots of children with a POPS of 5 at presentation are safely and correctly discharged. So POPS helps highlight a patient who needs an intervention (which may be something as simple as senior review) but shouldn't tell you what to do.

I try to emphasise that the patients presenting to an Emergency Department are usually in a pre-treatment phase of their illness (they've not had medications) and therefore the range of possible acuities is very wide (which is why POPS is 0-16). This is different from an inpatient PEWS which is looking to identify children in a post treatment phase who are deteriorating. The bandwidth of PEWS (typically 0-7/8) is therefore smaller.

Finally POPS was designed to also help support decisions on 'wellness'. A POPS of 0 has a very high positive predictive value for being discharged without subsequent return and admission. It's the volume analogy in reverse. A POPS of 0 screams: why are you admitting me? And in some cases (DSH, Risk from specific past medical history, Social Concerns) you will do but it's the cognitive prompt that's the important thing.

Thanks Edward for shining a light on this important topic. I am happy to share copies of my paper explaining POPS "Scoring systems in paediatric emergency care: Panacea or paper exercise?" https://onlinelibrary.wiley.com/doi/abs/10.1111/jpc.13123 on request.

Thursday, 17 October 2019

The NYCE guideline for viral induced wheeze - Let's clear a few things up

If you’re unsure about how to manage viral wheeze in children, you’re not alone.  There is much confusion about this common paediatric presentation.  The uncertainty about best management exists for several reasons.
  • Research: The research on interventions is usually age based rather than specific to the condition being treated.
  • Guidelines: There are very few guidelines specifically for viral induced wheeze.  No national guidelines exist.  Some centres use asthma guidelines for acute treatment of viral wheeze while some develop  local guidelines which have significant variations.  
  • Front-line: There is often uncertainty about the diagnosis.  Telling the difference between bronchiolitis, vial induced wheeze and asthma/multi-trigger wheeze can be a challenge.

When you see a wheezy child, you want answers to all these questions.  So here we go, one at a time.

Question 1 – Does this child have viral induced wheeze?
If the child in front of you is snotty and between the ages of 12 months and 5 years then the answer is “almost certainly.”  Almost is somewhat unsatisfactory so here is the breakdown of that statement.

Wheezy children under the age of 12 months usually have bronchiolitis, a condition that is also induced by a virus but involves wetness of the small airways rather than bronchospasm of the larger airways.

Wheezy children over the age of 5 years might still have viral induced wheeze but asthma is a more significant possibility in this age group.  Children under the age of five may also get wheezy with other triggers but there is debate about what this should be called (e.g. multi-trigger wheeze) and when a diagnosis of asthma is given under the age of five it can easily turn out to be wrong.

The most certainty about the diagnosis of viral induced wheeze exists in those children between the age of 12 months and 5 years who
  • Only wheeze with a viral illness
  • Have a relatively rapid onset of wheeze
  • Have demonstrated response to beta-agonist treatment

It is worth knowing that there are wheezy presentations in this age group that can look a lot like viral wheeze.  These include bronchomalacia, acute allergy, and cardiac failure due to e.g. acute myocarditis.

Question 2 – What and how much treatment should I give to a child with viral induced wheeze?
Treatment of acute viral wheeze is often extrapolated from asthma guidelines.  Most, such as the BTS guidelines, stratify according to severity, mainly based on signs of increased work of breathing.

Other factors to consider include the child’s previous history of wheezy episodes.  It is reasonable to treat children who have progressed to needing a critical care level of treatment on previous occasions more aggressively in terms of treatment and more cautiously in terms of admission.

It is also well worth considering is whether the child has received effective treatment prior to presentation.  If the child has either been given no inhaled beta-agonists at home or the delivery has been ineffective, they are more likely to respond to a more conservative dose of inhaled treatment.  If they have been given substantial and effective treatment at home and are working hard to breate despite this, they are more likely to need a larger number of puffs to achieve an improvement.

Here is an example of how to treat an acute viral wheeze at presentation to primary care:





































The use of oral steroids in children with viral wheeze is controversial.  Much of the available research looks at wheezing within an age group, not categorising children into phenotypes of underlying cause.  This has led to age based approaches by some and a selective approach to using steroids by others.

The best evidence (1) for the use of oral steroids for viral wheeze between the ages of 1 and 5 would suggest that the following group are most likely to have a small benefit:
  • Children with a diagnosis of asthma
  • Children who have required substantial amounts of inhaled beta-agonist prior to presentation
  • Children whose severity and lack of response to treatment with beta-agonists requires admission to hospital

One simplified application of this evidence is to say that if the child does not have asthma and does not require in-patient treatment, there is too little evidence to support the routine use of oral steroids.  Note that a family history of atopy, though often used in decision making here, is not an indicator that the child is likely to benefit from steroids.

Question 3 – Should this child be admitted?
The answer to that will depend on various factors including clinical setting and local infrastructure.  In an urban primary care/ secondary care model, admission should be the norm in the pre-hospital setting for children with a moderatel or severe episode who have required significant quantities of salbutal and are not responding well. 

Children whose severity is judged to be mild, and those who are moderate at presentation but respond well to their first dose on inhaled beta-agonist can usually be managed in the community.

Risk factors such as prematurity, comorbidities, pervious life-threatening episodes, parental confidence/competence and adverse social circumstances should all be involved in this important decision.

Question 4 – How much beta-agonist should the parents give if I am sending them home?
There is huge variation in practice here.  Experience tells us that paradoxically children tend to need larger doses of inhalers rather than standard or small doses.  This is likely to be due to a combination of delivery (getting all that is given to where it will count) and physics, since children’s airways have different flow dynamics to adult airways.
The majority of clinicians will recommend that the child receives 6-10 puffs of salbutamol 3-4 hourly.  Note that local guidelines vary in terms of dose and interval.  There is a certain amount of clinical judgement involved which will be influenced by the presentation and the circumstances (including the parental confidence and competence with delivery of inhalers and their ability to recognise markers of deterioration.)

What guidelines often fail to explain are the aims of treatment at home.
  • To get the child’s breathing looking normal or nearly normal
  • To maintain that improvement for at least a couple of hours and ideally four hours
  • To prevent the viral wheeze from affecting the child’s activity, ability to feed etc.

It is useful to tell parents that the inhalers will not treat the symptoms of the viral illness such as cough and runny nose.

Treatment failure is generally considered to be:
  • Significantly increased work of breathing despite inhaled beta-agonists
  • Worsening severity – progressively requiring more puffs or more puffs at shorter intervals
  • Parental global concern about the appearance or wellness of the child

A further variation in practice is how people manage the issue of reducing/ stopping the inhaled beta-agonist treatment.  Viral wheeze is by definition a time limited problem.  As the effect of the virus and the child’s immune response resolve, so does the bronchospasm.  There are two main approaches to the way that people advise how to move towards stopping the inhaler.
  • A set weaning regime – many centres have a planned weaning regime for inhalers that is given to parents.  This sets out a planned reduction of the number/ frequency of inhaler given to the child.  It is usually written down and given to the parents for them to follow.
  • A weaning plan that is not prescriptive – it is equally common to give parents a plan that puts them in the driving seat.  Often, it recommends a set dosing and interval for a set period (e.g. 6 puffs four hourly for two days) to be followed by a period of using the inhaler when it is apparent that the child would benefit (e.g. increased work of breathing or audible wheezing).

Each approach has pros and cons.  A set weaning regime carries a risk that the parents will follow it even when the child is not ready.  A weaning regime that requires parental judgement carries a risk that the inhalers will continue to be given when not needed (e.g. to treat a cough) or that the parents will simply stop after two days and not recognise the child’s need for further inhalers.

Whichever approach is used, the risks can be managed by careful explanation of what to do, how to do it and when to divert from the plan.

It's important to know the uncertainties and variations in practice.  It's also important to have a guideline.  Viral wheeze has always been a paradox in that regard.  There is a broad concensus that viral wheeze is not asthma, yet there has always been a tendency to shoe-horn the management of viral wheeze into asthma guidelines.  Perhaps it is time that viral wheeze had its own guideline.  Wouldn't that be NICE.

Edward Snelson
@sailordoctor
References
  1. Foster S et al, Oral prednisolone in preschool children with virus-associated wheeze: a prospective, randomised, double-blind, placebo-controlled trial, Lancet, Vol 6, Issue 2, P97-106, Feb 01, 2018

Friday, 27 September 2019

Are you thinking what I’m thinking? – Assessing response to inhalers in the wheezy child

Imagine that you’re in a training post and working in an acute paediatric setting.  A nurse gets your attention and says, “Would you have a listen to this child please?  They are due their salbutamol but I wonder if they are ready to space*.”
* Increase the interval between inhalers.

Most of us have heard those words or something very similar.  I suspect that most of us are never actually taught exactly what we should assess when reviewing a child post salbutamol.  We are making assumptions and reverting to our safe place of “more is more” when it comes to clinical information.  What is also interesting is that a large number of clinicians feel that auscultation is not the most important part of the assessment.  Many feel that the auscultation bit is positively unhelpful when reassessing a wheezy child.

So, what is the deal?  Does the noisiness of the wheeze matter after the initial assessment?

Let’s consider a case.  Three year old Adam has developed a wheeze after four days of having a cold.  He didn’t have any treatment at home.

When you clinically assess Adam, he is snotty but looks well and is hydrated.  He is sat on his parent's knee, playing with his favourite soft toy – a ragged bunny rabbit covered in drool and snot.  You can see from where you sit that he has increased work of breathing and you can hear a quiet wheeze.

On closer physical examination you see moderate intercostal recession and tracheal tug.  On auscultation there is a loud wheeze throughout his chest.  There are no focal signs.  Other than signs of an uncomplicated URTI, examination is normal.

What is the diagnosis?

Adam is too old for bronchiolitis to be a real possibility.  In any case the onset ofthe wheeze very much goes against bronchiolitis as a diagnosis. (1)  Asthma is also very unlikely.  This is his first episode of wheeze, he is three years old and there is a clear viral trigger.  Viral wheeze is the winner of the “what is the likely diagnosis?” competition?

How should Adam be treated?

Viral wheeze is the poor cousin of the childhood wheeze family.  Very little guidance exists compared to Asthma or bronchiolitis.  There are plenty of RCTs but these tend to focus on wheeze in certain age groups and avoid the issue of viral wheeze vs asthma (or multi-trigger wheeze).

The only uncontroversial treatment for viral wheeze is beta-agonist therapy (e.g. salbutamol).  Regardless of you views on steroids and montelukast as rescue therapy for acute viral wheeze, beta-agonists are the only intervention that will have immediate effect.

Oral steroids might be used for a child like Adam but the evidence for this is conflicting and confusing.  The latest research supports a practice of reserving steroid use for more severe cases and those in which response to salbutamol is poor. (2)

There is no consensus on how many puffs of salbutamol you should give a child such as Adam.  10 puffs of salbutamol via a spacer is what many would recommend.  What happens next is the more uncertain element.  The main aims of the game are to make Adam feel better and to make sure he is clinically safe.  How we assess all of that comes back to the original question.

How do we assess response and improvement (in viral induced wheeze) following beta-agonist treatment?

There are actually several ways of doing this.  There is no absolute consensus on what measures should be used and, as usual, in that situation, there is a broad spectrum of practices involved in what gets assessed and what gets particular weight put on it.

Let’s look at each option and think about the pros and cons of each.

The noise
Wheeze is a musical sound like any other.  The bronchial tree happens to be the musical instrument.  Anyone who has ever tried to play a brass or wind musical instrument will tell you that it’s not how hard you blow that matters the most.  Wheeze is subject to the same musical rules.  The amount of air being moved, the constriction of the airways and the pattern of breathing will all have an effect on the loudness of the wheeze.  Wheeze can be absent in children with bronchospasm.  It can be louder as the child improves.  Wheeze can persist even when all other signs and symptoms are resolved.

Wheeze is a hugely valuable clinical finding.  It tells you that you are dealing with a wheezy illness.  That limits the possibilities and it is important to have definite wheeze at some point when diagnosing an illness (e.g. asthma) that has wheeze as a primary symptom.  The significance of what happens to the wheeze once treatment has begun is less certain.

Auscultation can be misleading in other ways.  Focal crackles are very common in viral induced wheeze.  This can create anxieties about the presence of secondary infecton.  The good news is that wheeze is a strong negative predictor of bacterial LRTI. (3)  If the child looks really well, a few crepitations in one zone is a poor indicator of pneumonia.

What is certainly true is that auscultation is essential if there is any sign of deterioration (worsening recession or child becomes more tired) as this could indicate a number of things.  Even then, the wheeze will probably not tell you what you need to know i.e. has something else happened such as a pneumothorax or a collapsed lung.

Another issue with using auscultation findings is that this only happens when a clinician is present.  When the child is at home, this is not part of the assessment.  It could be argued that the implication that auscultation is important undermines the confidence of a parent or carer who is required to make ongoing decisions about whether the child can continue to be treated at home or needs to return for further medical assessment.

The visible signs of abnormal breathing
The visible effort of breathing is a more logical measure of the severity of bronchospasm.  Look at respiratory rate, recession, tracheal tug and use of accessory muscles.  The severity of these signs, regardless of the degree of wheeze, are more likely to indicate what treatment is needed.

There are three important caveats to this.  Firstly, if a child is becoming tired, these signs might become less apparent.  Improvement should be accompanied by an increase in activity if it is to be truly considered a sign of resolution of bronchospasm.  Secondly, the child with neurological or muscular abnormality will have less visible signs.  These children should be treated in the knowledge that what we see may not reflect how bad the problem really is.  Thirdly, the adolescent is more likely to be having a more severe episode with minimal visible signs.

The overall appearance and behaviour of the child
The appearance and behaviour of a child are measures of efficacy of breathing.  Essentially, they tell us about what the problem means for the all-important end organs.  If a child has wheeze but is running around, the end organs are telling you something.  If the child is subdued and inactive, this is important clinical information.

What next for Adam?

After being given salbutamol, Adam is running around and playing.  He has no recession and no use of accessory muscles to breathe.  He chatters away with no signs that he is short of breath.  Do you need to listen to his chest to decide what to do with him next?

The bottom line is that whether or not you auscultate the chest when reassessing a child with viral induced wheeze, you probably shouldn’t put too much emphasis on what you hear if there are visible signs of improvement.  As is so often the case in paediatrics, the take home message is simple: look at the child.

Edward Snelson
Mill Town Keeny
@sailordoctor

Disclaimer: If a wheeze falls in the forest and never causes other signs or symptoms, was it ever there?
References
  1. Snelson E., A simple model for understanding the causes of paediatric wheeze, Paediatrics and Child Health, Volume 29, Issue 8, 365 - 368
  2. Foster S et al, Oral prednisolone in preschool children with virus-associated wheeze: a prospective, randomised, double-blind, placebo-controlled trial, The Lancet Respiratory, Vol 6, Issue 2, P97-106, Feb 01, 2018
  3. Shah SN, Bachur RG, Simel DL, Neuman MI. Does This Child Have Pneumonia? The Rational Clinical Examination Systematic Review. JAMA. 2017;318(5):462–471. doi:10.1001/jama.2017.9039

Sunday, 8 September 2019

It’s all about the sequence - Reflex anoxic seizures and breath-holding attacks in children

There are a couple of childhood phenomena that every clinician should know about.  These events are terrifying to parents yet they are safe and not harmful.  When children have a reflex anoxic seizure or a breath holding episode, it will sound alarming to the clinician to whom the child presents.  The extreme nature of the event might suggest a diagnosis of epilepsy or head injury.  It is possible to distinguish these phenomena from their better known counterparts.  The best bit about diagnosing reflex anoxic seizures and breath holding episodes is that no tests are needed – it’s all about the sequence.

Let’s look at two cases:

Case One – Gina

Gina is an 18 month old toddler who has always been fit and well apart from the usual respiratory tract infections that go with the territory of being a young child.  Gina was born by normal delivery, following a healthy pregnancy and was well at birth.

Gina’s parents have attended following an event which occurred this morning.  Gina was playing when her older sister took away her toy.  Gina cried for a minute while her mother negotiated with the older sister to resolve the situation.  Gina’s mother then noticed that Gina’s crying sounded quieter and looked to see that Gina was turning a deep purple colour.  There were no objects that Gina could be choking on.  As her mother went to pick her up, Gina stopped breathing altogether and then went floppy.  While still unresponsive, Gina then started breathing and slowly her colour returned to normal.  As she improved in colour, she became responsive.  Within minutes she seemed completely normal.  Her parents have brought her to find out what happened.

Gina is now looking very cheerful and is exploring the room you are in.  She has a normal cardiorespiratory examination.  Her neurological examination is normal for her age.

What did happen to Gina?

Gina has had a breath-holding attack.  This is a phenomenon in which disordered breathing leads to prolonged expiration and a temporary failure to inhale.  Sometimes these events simply result in a blue episode and then self-resolve.  In some cases, the child may actually stop breathing and collapse.  When this occurs, the normal respiratory drive re-sets and the child recovers as a result.

Case 2 – Tina

Tina is a 2 year old child who is usually fit and well.  Tina has been brought by her parent following an event that has just happened this morning.

Tina was running around and having a lot of fun in her house this morning. She then banged her head on a door handle.  Her mother was there when it happened and there says that Tina started crying immediately.  After just a few seconds of crying Tina, suddenly went pale and collapsed to the floor.  She looked as though she was dead for a few seconds and then she went stiff.  After that she had a few jerking movements and then stopped.  Her colour then improved and she started to make some normal movements.  Tina then slowly returned to being her normal self over about 30 minutes.

When you examine Tina, she is back to normal and trying to climb onto the chair.  She is laughing and interactive.  She has a normal cardiorespiratory examination.  Her neurological examination is normal for her age.

What happened to Tina?

Tina has had a reflex anoxic seizure.  This is another phenomenon seen almost exclusively in young children.  A noxious stimulation (pain or surprise or emotional upset) causes an extreme vagal response.  This leads to hypotension and bradycardia.  Circulation is briefly arrested causing a collapse and the alarming change of colour.  In some cases the episode resolves from this point.  In some cases the sudden loss of cerebral perfusion leads to a seizure, which is usually brief.
Whether a seizure occurs or not, the child will reset and recover.  It is likely that the collapse itself stops the vagal overstimulation.

Breath-holding attacks and reflex anoxic seizures have many features in common with each other.  Both occur in young children.  Both cause colour change, collapse and self-resolve.  Both phenomena are terrifying for a parent to witness.
The way to tell the difference between a breath holding attack, reflex anoxic seizure and other cause of collapse is by listening to the sequence of events.

Telling the difference between a breath-holding attack and a reflex anoxic seizure is not crucial.  The management of the child who has had one is exactly the same.  The most important thing is to tell the difference between these two phenomena and a traumatic or idiopathic seizure.

Following a reflex anoxic seizure (or reflex anoxic spell without seizure) or breath-holding attack, the most important things to do are as follows:
  • Examine the child.
  • Ensure the child has a normal cardiorespiratory and normal neurological examination.
  • Explain the event to the parent.
  • Tell the parent that these episodes fix themselves because the child’s breathing and circulation have an automatic restart mechanism that is not affected by the breath holding or reflex anoxic seizure.
  • Explain that it is possible that the child may have further episodes.  If this occurs they should allow the child to collapse to a lying position.  Holding the child up delays the return of circulation.
In which case, trust the sequence. It is worth pointing them to a good information source such as the STARS patient information (Reflex anoxic seizures).

If the diagnosis is clear and the examination is normal, there is no need for investigation or follow-up.  Some clinicians will do an ECG but if there is genuine suspicion about an underlying arrythmia, a resting 12 lead ECG is not an adequate test.  If there are suspicious features in the history or examination, a 12 lead ECG should be a stepping stone to further investigations such as a 24 monitor.

In most cases the diagnosis is apparent and the examination is normal.

Edward Snelson
Consequential clinician
@sailordoctor

Disclaimer - If you get a Fibonacci sequence, that's worth a case report.

Tuesday, 30 July 2019

Core Principles of Paediatrics

Treating sick kids is a lot of fun.  If you can deal with any fear factor, it becomes a real pleasure most of the time.  Children are very different from adults.  While much that you know about adult medicine is useful, it usually needs a big modification to apply into practice when assessing and treating a child.  This post is going to cover some of the core principles of paediatrics as well as giving some specific examples.

Let's start with some basics:

The paediatric consultation is inherently different.  In most situations the child is part of a consultation which involves a third party, usually a parent.  That dynamic needs to be handled carefully and it is important to never forget that the child is still the patient.
When it comes to examining a child, it can be a little daunting.  In most cases, it is possible to get cooperation by making the examination fun.  There are various ways to do that but my go-to method is the "Find the food" game.  A full explanation of how that works is here.  In many cases you just have to be opportunistic and accept that there is no set piece for the examination.  In paediatrics, we can only base our assessment on the examination that is achievable.  Incomplete information goes with the territory, but it is usually possible to make an assessment.  Thankfully, the most important information usually comes from the history and from the hands-off element of the examination.
When it comes to making an assessment and deciding on a management plan, it is important to consider the age of the child.  Children get different problems at different stages of childhood and the way they respond to infections changes considerably at different ages.

Babies*
  • Immune system is heavily reliant on maternal antibodies
  • Simple viral illnesses are uncommon
  • When a baby is febrile or unwell, the likelihood of serious bacterial infection (SBI) is high.  
  • The response to SBI is sometimes vague and does not make it easy to recognise SBI.  Babies who are "off feeds" or "not their normal selves" should be taken seriously.
  • Physiological reserves are low in this age group.  Babies can compensate to a degree but are prone to sudden deterioration is moderately unwell, especially when the lower respiratory tract is affected.
  • The lack of any ability to report symptoms means that certain problems such as urinary tract infection (UTI) and surgical abdominal problems can easily go unrecognised.
*I have deliberately not attributed an age range to the term baby.  Everything here is more true for a 2 day old than it is for a 2 month old but the same principles apply.  If you really want to know if it's a baby, put it on the floor in the middle of the room.  If your patient is exactly where you left them 5 minutes later, it's a baby.

There are some simple principles to apply when assessing a baby:
  • Take any abnormal temperature (low or high) seriously.  Unless there is good evidence of a benign cause (wearing too many layers or fever post vaccination) and the baby is well, presume SBI.  In primary care/EM that means referring.  In paediatrics that means a period of observation as a minimum and in many cases the outcome is investigation and presumptive treatment.
  • Absence of fever is not absence of significant infection.
  • Take into account risk factors such as prematurity
  • Remember to do a few specifics in the examination - assess posture and limb movement, feel the fontanelle, weigh the baby (and measure head circumference in many cases) and feel femoral pulses.
  • Babies can seem "a bit off and" then be absolutely fine when assessed/ observed.  When sending the baby home, make sure that the parents know how important it is to be reassessed if there is deterioration or new symptoms.  They must never hold back from seeking assessment due to fear of being perceived as an anxious parent.
  • Conversely, many of the things that parents might worry about are often within normal, including regurgitation of feed, frequent crying and straining at stool.  In general, if the baby looks well, grows well and examines normally, these things are likely to be part of normal infancy.
Toddlers and Pre-school Children
  • No longer relying on maternal antibodies and not yet an educated immune system, this age group has a cunning survival plan - the immune system that goes crazy with every simple infection.  Simple upper respiratory tract infections provoke high fevers, high white cell counts and produce an array of other phenomena in this age group.
  • The phenomena that occur relating to viral infections in this age group include transient synovitis (irritable hips), viral induced wheeze and febrile convulsion.
  • The fact that these children get so many viral illnesses coupled with the fact that they can seem quite unwell with simple viral illnesses means that a large proportion of healthcare presentations at this age are for viral illnesses.  In contrast to babies (rule out SBI/ sepsis) the approach in this group is more usually rule in SBI/ sepsis.
  • The low probability of SBI/ sepsis in this age group presents many challenges to front line clinicians.  It is essential to remain vigilant and to approach even the most straightforward illness as though it could be or become SBI/ sepsis.
  • The prevalence of asthma in this age group is very low.  There are plenty of presentations that could be misdiagnosed as asthma but it is important not to be misled.
Older Children and Young People

  • The transition into this stage of childhood is more gradual.  Viral infections continue to occur frequently to begin with (especially as the child first goes to a new school) but become less common.
  • Response to infections is slightly less vigorous and the phenomena associated with the previous stage suddenly become rare.
  • Asthma now becomes a more significant possibility.
  • As this stage of childhood develops, the pattern of disease and clinical presentation becomes progressively more adult like.
  • The non-clinical needs of the patient tend to remain childlike more than clinicians sometimes realise.  It's daunting being a patient when you're not an adult.
Much of paediatrics is about understanding these stages of childhood.  In each stage, the challenges are different.  This "stages of immune system development" maps well to the approach to illness at each stage as well as to the various causes of childhood wheeze.
The Pitfalls

It's good to know what might catch you out.  Here are a few of the common pitfalls.

Extrapolating adult practice into paediatrics-  This rarely works.  The probabilities are different, the way that they present are different and the therapeutics are different.  Here are few examples of major differences in common problems that can occur in children and adults.

Doing something-  For many childhood presentations, paediatrics is the art of doing as much nothing as possible.  It can feel like doing a test or giving a treatment "in case" is the safe option but there is no such thing as a zero-harm test or treatment in paediatrics.  Where a test or treatment is absolutely indicated you are on safe ground.  For example with croup, dexamethasone is never wrong.  In many scenarios, a test could be done or a treatment could be given.  If that is the case, always consider the possible harm.

For example:
  • Upper Respiratory Tract Infections - antibiotics can often be justified and this can feel like a satisfactory way of dealing with parental expectations.  However, antibiotics often cause vomiting and diarrhoea and the likely benefit is small.  Antibiotic prescribing risks shifting the focus from good symptom control and the perception that antibiotics are a safe option is misleading.
  • Bronchiolitis - doing a chest X-ray (CXR) may feel like a good way of completing a clinical assessment.  The reality is that it does not add value exept in extreme cases.  The great likelihood is that the CXR will show something that can be interpreted as bacterial LRTI, leading to a prescription of antibiotics despite the evidence that wheeze virtually exludes bacterial LRTI.  Now you have a baby with bronchiolitis who is being given antibiotics when what they most need is to hydrate orally and be allowed to cope with thier wet lungs without unecessary upset.
In paediatrics, careful assessment, observation if needed and careful safetynetting are the cornerstones of safe practice.  Doing tests and giving treatments "in case" are not as safe as they feel.

Feeling the pressure-  Worrying about knowledge gaps or inexperience with paediatric presentations is quite normal.  It is common for clinicians to have niggling anxieties about their assessment of a child.  If in doubt do the following things:
  • Look at the child.  Their appearance and behavior will often tell you whether that concern may be valid.
  • Use every contact as a learning opportunity.  If you have worries about something, learn about that presentation for the next time.
  • Don't hesitate to ask for help or advice.  If you have doubts about the best management of something you feel you can deal with yourself, discuss that plan with someone experienced.  In many cases, that will be someone in your team but it can also be a paediatrician on call.  They might want to see the child but they may be happy to discuss and advise.  If you do refer a child for further assessment, find out what happened next.  That way you can educate your own clinical judgement.
Finally, if you are or become that person that someone goes to for advice or a further opinion, be helpful.  Remember how daunting it is when you first started seeing children and how much uncertainty is entirely appropriate.  If you end up seeing the child and they don't need any investigation or intervention, remember how much childhood illness can fluctuate in severity.  As the expert, you will undoubtably add value, even if it is simply in the form of an experienced assessment and brilliant safetynetting.

Edward Snelson
Induction agent
@sailordoctor

Disclaimer - Remember that when you look at a child, wear full personal protective equipment.  If you're new to seeing children, you're in for a viral rollercoaster.

Sunday, 30 June 2019

Chest X-rays in children - The Wimbledon Rules

We've come a long way in terms of reducing unnecessary tests in paediatrics.  It is within my career that it was standard to obtain a chest X-ray (CXR) for any child presenting with their first episode of wheeze.  Now, such an approach is seen as outdated.  This is a good thing.  In fact the vast majority of acute and sub-acute respiratory presentations in children can be managed without needing a CXR.

In some ways it was a lot easier to know when to do a CXR 20 years ago.  The answer was pretty often.  Every lower respiratory tract infection (LRTI), every first episode of wheeze and every persistent cough tended to result in a CXR.  Now, we should rarely do CXR in those circumstances.  Rarely doesn't mean never though, so how do you know if you're doing too many?  Enter the Wimbledon Rules for CXR in children…  I’ll come to that later.  First, I’ll explore a little bit about the complexities of doing CXRs in paediatrics.

The problem with CXR in children is that it can be misleading.  The most common scenario in which this is true is for the wheezy child.  Wheeze is a strong negative predictor of pneumonia(1).  This makes sense clinically when you think about it.  If an infant or child has restricted lower airways, that is reason enough to have respiratory distress.  If you then take a section of lung out of action, you won't be wondering if they might have a problem.  It is likely to be very obvious from how unwell they are and how abnormal their breathing is.  As a rule, children with tight airways and pneumonia together are in a very bad way.

While wheeze is a strong negative predictor of pneumonia, a CXR in wheezy children is rarely clear.  In many cases there is a patchy white area on the CXR.  This is often at the right heart border, or as it is sometimes called, "the area of radiological romance."  If you do a CXR too often in wheezy children, this will happen fairly frequently and it may be difficult to ignore.

Even if a child does have a LRTI, CXR is not necessary in many cases.  The British Thoracic Society (BTS) guidelines for community acquired pneumonia (CAP) recommend the following:

  • Chest radiography should not be considered a routine investigation in children thought to have community acquired pneumonia. 
  • Children with signs and symptoms of pneumonia who are not admitted to hospital should not have a chest x-ray.

These recommendations are based on two important facts.

  • Children with clear clinical signs of CAP may have a normal CXR
  • Children with abnormal findings on a CXR often do not have clinically significant CAP (2)

So when should we do CXR in children?

Let’s start with the times when CXR is not recommended routinely:

  • Bronchiolitis not requiring admission to a critical care unit (PCCU)
  • Episodes of asthma and viral wheeze (no matter how severe or whether it is the first episode of wheeze for that child) which are responding to treatment
  • Community acquired pneumonia without atypical features and which responds to treatment within the first two days
  • Most cases of cough without other features
  • Chest pain in children

CXR is usually most helpful in children in these circumstances

  • Severe exacerbations of asthma or viral wheeze which are getting worse despite appropriate treatment 
  • Community acquired pneumonia which has atypical features or fails to respond to appropriate treatment
  • Daily cough with any of the following features
    • Lasting more than 8 weeks
    • Progressively worsening over several weeks, esp. if moist cough
    • Red flag features (daily fever, night sweats, weight loss)
    • Known exposure to TB
    • History consistent with inhaled foreign body

The other side of the problem is that there is no gold standard test for many of those clinical scenarios where CXR is not routinely recommended.  There is often poor correlation between clinical and radiological findings, but which is more valid?  For example if you take pneumonia in children and treat based on radiological findings versus clinical findings you will end up treating different children.  Clinical findings will be falsely positive and falsely negative just as radiological findings are.

Therefore we need to get a balance between clinical common sense and judicious use of CXR in children.  A simplistic approach which could be applied looks like this:
Whether a CXR is necessary or not is highly subjective.  Ask ten clinicians and you'll get ten different answers, due to the human factors.  It's a little like an umpire in a tennis game.  They're not right all of the time.

For this reason, in a major tournament tennis game, players are allowed to appeal.  However the players appeals are limited.  If they appeal against a decision and that appeal is upheld, they retain the number of appeals that they had before the appeal.  So wrong once, they can appeal again.  Wrong twice and they're out of appeals.

I suggest that clinicians should apply the same rules to the use of CXR in children.  Before doing a CXR, we should ask ourselves the question, "What would I do based on a purely clinical assessment?"  After doing a CXR, we should then ask, "Has the CXR added genuinely useful information to my clinical decision?"

Having a CXR result in a child which doesn't alter our clinical decision, or which dysfunctionally suggests a pathology in the absence of a congruous clinical picture should make us rethink our approach to our use of CXR.  If we're going to apply the Wimbledon CXR rule, when we get one completely normal CXR (or one with a non-descript small white fluffy patch which makes us want to give antibiotics when we wouldn't have done so before the CXR) we should think about more cautious use of CXR. If we get two, we should stop and re-read the rules.

Just as tournament tennis players don't have an unlimited number of appeals, we shouldn't think of CXRs as an unlimited diagnostic resource.  We should use them when they are most likely to change our game.

Edward Snelson
Unappealing Paediatrician
@sailordoctor

Disclaimer: If you turn the umpire off and back on, the number of appeals resets.
References
  1. Hirsch, A. et al., Estimating Risk of Pneumonia in a Prospective Emergency Department Cohort, The Journal of Pediatrics, Volume 204, 172 - 176.e1
  2. Virkki R, et al. Radiographic follow-up of pneumonia in children. Pediatr Pulm 2005;40:223e7.