Galeazzi fracture-dislocations

Cite this article as:
Rie Yoshida. Galeazzi fracture-dislocations, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.21150

Patrick is a 15-year-old boy who presents to the Emergency Department with a painful left arm.  He tells you he fell off his bicycle, putting out his left hand out to break the fall.  On examination, his left forearm is deformed at the wrist.  There are no open wounds and no signs of compartment syndrome. The limb is neurovascularly intact.  

He has declined analgesia in triage but you convince him to take paracetamol and ibuprofen prior to his x-ray. You order a lateral and AP film of his left forearm including the wrist and elbow.  

Th. Zimmermann [CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0)]
His x-ray shows a distal radial fracture.  Whilst you are assessing the degree of angulation, a medical student leans over your shoulder and asks, ‘Should the head of the ulnar be sticking out like that?’. You nearly missed it but Patrick has a rare Galeazzi fracture-dislocation! 

Galeazzi fracture-dislocations consist of a fracture of the radius with dislocation of the distal radio-ulnar joint.  The fracture usually affects the distal third of the radius.

Galeazzi injuries are very rare in children (more commonly seen in the adult population).  The mechanism of injury is usually due to a fall on an outstretched hand with forearm rotation.

Examination findings

Examine the forearm, wrist and elbow joint.

Inspection and palpation: swelling, tenderness and likely deformity of the distal forearm and wrist. Check for any open wounds.

Range of movement: Maybe reduced at the wrist joint.

Check for signs of neurovascular compromise or compartment syndrome.  Ulnar nerve injury is uncommon.

Investigations

True AP and lateral X-rays of the forearm including the wrist and elbow (including distal humerus).

The key point here is if a distal to mid-shaft radial fracture is seen on  X-ray, have a good look for signs of distal radioulnar joint disruption.

Classification 

Galeazzi fractures are classified according to the direction of ulna displacement.

Galeazzi-equivalent fracture

A Galeazzi-equivalent fracture may occur in children.  This characterised by both

  • fracture of the distal radius
  • fracture of the growth plate of the ulna (separation of the ulnar physis), as opposed to dislocation of the distal radio-ulnar joint, DRUJ.

Treatment

All Galeazzi fracture-dislocations should be referred to orthopaedics on-call as a surgical intervention may be required for unstable or irreducible fractures.  The usual approach in children is conservative management with closed reduction and immobilisation in an above-elbow cast.  They should be followed up in the fracture clinic in 7 days.  Complications include malunion, compartment syndrome and nerve injury but these are more common in adults and if the diagnosis is delayed.  Children tend to have good outcomes with closed reduction and casting, even if the diagnosis is initially missed.

You are congratulated by the ED consultant for identifying Patrick’s Galeazzi fracture-dislocation.  You call the Orthopaedic surgeons.  It is a stable fracture and he has a successful closed reduction performed under procedural sedation in ED.  An above-elbow back slab is applied.  A few hours later, Patrick is ready to go home as he has recovered from the sedation.  On their way out, his mother asks you if he will recover fully.  You explain that he will be followed-up in the fracture clinic in 7 days but that his outcome should be good as the fracture was identified early and the post-reduction x-ray shows good alignment.  On your next day off, you decide to make a table of the differences between Monteggia and Galeazzi fracture-dislocations to aid your memory. 

[wpsm_comparison_table id=”10″ class=””]

*One way of remembering that both Monteggia and Galeazzi require review by orthopaedic surgeons is to remember that both fracture types are named after Italian surgeons!

Top tips

  • If you identify a distal to mid-shaft radial fracture, look for signs of distal radioulnar joint disruption or ulna physis disruption.
  • A useful mnemonic to remember the key differences between Monteggia and Galeazzi fracture-dislocations is MUGR (Monteggia fractured Ulna, Galeazzi fractured Radius)

Selected references

Eberl, R., Singer, G., Schalamon, J., Petnehazy, T. and Hoellwarth, M.E., 2008. Galeazzi lesions in children and adolescents: treatment and outcome. Clinical orthopaedics and related research466(7), pp.1705-1709.

Johnson NP, Smolensky A. Galeazzi Fractures. [Updated 2019 May 2]. In: StatPearls. Treasure Island (FL): StatPearls Publishing; 2019 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK470188/

Ethical considerations and decision-making about the resuscitation of very sick children

Cite this article as:
Karen Horridge. Ethical considerations and decision-making about the resuscitation of very sick children, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.30898

You wouldn’t judge a book by its cover, would you?

When thinking about the knotty matter of decision-making about resuscitation of sick children, we need to remember:

Every child’s life matters.

To always listen to the child, their parents and those who know the child best and include them in best-interests decision-making.

To always make decisions within an ethical framework and record the process of decision-making and who was involved.

To ensure pathways are in place to record and make visible best-interests’ decisions about levels of intervention.

So, what can help us with an ethical framework? Our friends at the General Medical Council have laid this out for us, in ‘Treatment and care towards the end of life: good practice in decision-making’.

Covers of GMC guidelines

This helpful document reminds us that:

  • Equalities, capacity and human rights laws reinforce our ethical duty to treat all children, neonates and young people fairly. 
  • We must always listen to child, parents and others close to them. We must take account of their views. Where there are different views, our primary duty of care is to the child.
  • Decisions must always be in a child’s best interests. 
    • We should weigh benefits, burdens and risks of treatment. 
    • We should consider all relevant factors in the decision-making process.
  • Decisions must start from a presumption in favour of prolonging life.

When making decisions, even in a dire emergency, we are reminded to:

  • Take account of up-to-date, authoritative clinical guidance.
  • In case of uncertainty, seek further expert opinions early.
  • Explain, justify and document all factors considered in decision-making.
  • Not rely on personal values when making best interests’ decisions.
    We must be careful not to make judgements based on poorly informed or unfounded assumptions about the impact of disability on the child or young person’s quality of life. 

So, you wouldn’t judge a book by its cover, would you?

Disabled children and young people come in all shapes and sizes. We can’t all be experts in each child, which is why it is so important for us to listen to parents and those who know the child best.

Please do beware of falling down the rabbit hole of preconceived ideas about what a child’s quality of life is like – always ask parents and familiar carers what the child is like when well. They may have photos and videos they can show you of their child having fun and taking part in everyday activities.

Disabled children may appear, sound and behave differently when unwell. This may be because they cannot tell you where it hurts or how they feel. They may present with behaviours that others may see as challenging. They may not tick the expected boxes on the usual screening tools, for example, for sepsis. Their temperatures may be low when you might expect them to be high, they might have high or low heart rates and may not be able to mount the expected increased work of breathing, because their respiratory muscles may be too weak for them to do so. Their control centres may not work as expected.

Hasty decisions based on preconceived ideas can lead to poor outcomes, including premature death. None of us want that.

So, what’s all this about premature death in people with learning disabilities?

If you are ready for a shocking read, then take a look at Death by Indifference, written by Mencap in 2006, but just as relevant today.

If you prefer some e-learning on the subject, take time to work through the Disability Matters session: Equal Access to the Best Health Outcomes Matters. This was co-produced with disabled children, young people, parent carers and other experts.

Then there’s the Confidential Inquiry into Premature Deaths of People with Learning Disabilities report. This report showed that women and men with learning disabilities die 29 and 23 years, respectively, sooner than women and men without learning disabilities.

So what about children? The series of reports on Why Children Die show that more than half of all children who die in England have a pre-existing, life-limiting condition. So, we all need to pay great attention and ensure we achieve the very best outcomes for these children and all children.

The team at Bristol University have built on the work they did for the CIPOLD report and now lead on the Learning Disabilities Mortality Review (LeDeR) programme. This links to the Child Death Review programme and considers the circumstances of every death of anyone with a learning disability at any age. The latest annual report can be found here.

Between 01/07/2016 and 31/12/2019, 516 children aged 4-17 years were notified to the LeDeR programme. Of these children and young people who died, 43% were from Black and Minority Ethnic groups. 46% had profound and multiple disabilities.

Whilst 7% of the deaths reported to the LeDeR programme were of children and young people aged 4-17 years, the death rate overall in the 5-19 years age group in England was 0.3%.

The LeDeR programme 2019 report highlights good and problematic practices that the multidisciplinary team, including people with learning disabilities, identified.

Good practices included:

  • Good care coordination across agencies and specialities
  • Excellent end-of-life care
  • Person-centred care, adjusted as the child or young person’s needs changed

Problematic areas of practice to reflect and learn from included:

  • Delays in responding to signs of illness or investigating illness.
    • This is known as ‘diagnostic overshadowing’, where clinicians may see the disabilities and think all presenting signs and symptoms can be explained by those, rather than undertaking a careful and structured clinical assessment to identify the underlying cause, such as pain from appendicitis, constipation, sepsis etc.
  • Poor quality multidisciplinary team working.
    • The needs of disabled children and young people are usually multifaceted and require a range of expertise to adequately assess and address them all.
  • Poor advanced care planning. 
    • Clinicians can be reluctant to have those difficult conversations with families about the risk of both sudden and unexpected death and also the risk of deterioration and death. We all need to do better on this.
  • Problems with the direct provision of care.

Recommendations from the LeDeR report included:

  • Identification of a key worker to coordinate care and communication for disabled children and young people.
  • Timely advanced care planning embedded in care pathways and clinical practice, responsive to changing needs.
  • Better discharge planning and better community support.
  • Consistent support and communication throughout each child’s life.

So where is the evidence about what parents think about end-of-life decision making? Dr Sarah Mitchell is a GP who is really interested in this and has written a useful paper in BMJ Open on the subject.

Sarah and her team interviewed parents and reported that:

  • Parents have significant knowledge and experiences that influence decision-making process
  • Trusted relationships with healthcare professionals are key to supporting parents making end of life decisions
  • Verbal and non-verbal communication with healthcare professionals impacts on the family experience.
  • Engaging with end of life care decision-making can be emotionally overwhelming, but becomes possible if parents reach a
    ‘place of acceptance’
  • Families perceive benefits to receiving end of life care for their child in a PICU 

With regard to the last statement, preferred place of death is, in my experience, different for each family. Some choose home, others need to know that no stone has been left unturned right to the end, so choose intensive care. Whilst this may not always sit comfortably with paediatric intensive care teams, for some families it is what is needed to bring them peace in their journeys of grief. I have been witness to what I would consider to be ‘good deaths’ in a wide range of settings, including homes, hospices, children’s wards and intensive care units over many years. What matters most and what families remember, are how the child’s needs were identified and addressed at every step and how they are families were kept in the loop about what was happening, including being fully involved in all decision-making.

Smiling boy with disability
Matthew

It’s all well and good listening to my views as an experienced disability paediatrician on the subject, but much better to hear directly from a mother who has been on the advance care planning journey. Here are Kay’s words, describing her and her family’s journey with her son Matthew. If you prefer to hear her speaking directly, please check out the Disability Matters e-learning session Advance Care Planning Matters.

Kay says:

“Matthew had quite severe learning and physical disabilities. He was a very complex child and we used the Emergency Health Care Plan to help plan for the future and to enable us to communicate fully with other health professionals in the healthcare setting. 

Matthew didn’t have the capacity to actually make decisions for himself although he was a very wilful little boy who had very clear likes and dislikes, so he could make decisions for himself that were relevant to his day to day needs like what he wanted to eat, where he wanted to go. He had no formal communication, but as parents and the people who were involved with him we learned to read what he was trying to tell us, and as I say, he was very clear on what he liked and disliked doing but wouldn’t have been able to make the kind of big decisions that as parents we were responsible for making for him.

We did have a very large team involved in Matthew’s care and we discussed the Plan with his consultant paediatrician but she also took into account the views of people like the occupational therapists, physiotherapists, the surgeons who were dealing with him as well as the parents, myself and Matthew’s dad. We were all involved in the discussions around the development of the Plan and what was in his best interests.

Matthew’s Health Care Plan went everywhere with him and it lived in his communication bag on the back of his wheelchair. So it went with him to school, to his respite and to his dad’s house when he was there and also it was with him whenever he needed to go into hospital.

The Emergency Health Care Plan actually protected Matthew’s rights should he ever become seriously unwell. It clearly stated that he needed full resuscitation and any treatment that was available to him and clinicians then could use the plan to make judgments on what treatment would be necessary but he was able then to access a full range of treatment that would be available to any other child in a similar circumstance.

Matthew was very well for the early part of his life but when he turned 11 he had an accident, a quite serious accident and we were able to use the Emergency Healthcare Plan to access full range of medical interventions for him, as a result of that he did end up in intensive care for the first time. After that we did go through a period when he was 12 he had a twisted bowel, so he was literally in and out of intensive care and needed to be resuscitated on quite a few occasions, unfortunately, but his plan enabled us to access all of this medical intervention for him and saved his life in that instance.

Over a period of about a year, Matthew became more and more unwell. He needed regular trips to Intensive Care and regular trips to the hospital. The Plan actually went with him to hospital in Newcastle. It gave us the assurance that during these periods of Matthew being very, very poorly that the doctors in the hospital that weren’t used to dealing with Matthew, the Plan gave them all the information so we didn’t have to go through it every time that he was admitted. They trusted what we were saying because it was backed up by the Plan”.

Matthew’s paediatrician says:
“Matthew developed a lot of new symptoms that were unexplained; his seizures were becoming less controlled and we needed discussions around how we were going to treat these new symptoms as and when they appeared and what needed to be done for them.

So at this point in time, having taken account of the views of both of Matthew’s parents and the whole of the multidisciplinary team, we made a decision in his best interests that, at that time, further intrusive procedures or further intensive care was not going to be helpful or appropriate for him and might cause him further distress. So, together, we changed the wording on Matthew’s Advanced Care Plan at that time to reflect the possibility of him being allowed a natural death when his time came, recognising that we would always be there to manage his symptoms and always be there to support his family”. 

Kay continues:
“Matthew had had a chest infection and was having great difficulty breathing and his dad brought him up to hospital. We called all the family, it was obvious that Matthew was dying at this point. We had all the family called from all corners of the UK to come and say goodbye to him. We sat for hours and hours with him in the hospital ward and he was almost pronounced dead when all of a sudden, he decided it wasn’t quite his time and he took a great big breath and started breathing normally and all his colour came back. His dad described it as, like, “re-booting” his system as he wasn’t on any treatment. He was having no medication or anything and he just decided “No, it’s not my time. I’m going to come back” and we had him for another five weeks after that.

Then one day, approximately five weeks after the “re-booting” incident, Matthew wasn’t very well at all. He was due to see his paediatrician in clinic that day, but I phoned and said that “I don’t think he’s up to actually travelling to hospital,” so the paediatrician agreed to visit at home, so we waited. He’d had a massive seizure. I’d had to give him medication to bring him back from the seizure. When his paediatrician arrived, it became obvious that he was deteriorating very, very quickly and we decided that we were just going to keep him at home and see what the outcome would be, whether he would “re-boot” again or how it would play out this time”.

Matthew’s paediatrician continues:
“So Matthew was really very frail on clinical assessment at this point, so I needed to put in place the right procedures to make sure that his needs were met and the family’s needs were met. He was very peaceful and he was essentially drifting off to sleep. He didn’t have any difficult symptoms at that point that needed any changes in medication or changes in his Plan. What we did at that point is I made arrangements for if Matthew was to slip away in the night, a colleague to be able to come out and support the family and to confirm his death at that point. I also contacted the Coroner, because our Coroner liked to know in advance about any child’s death and if there is a death that is likely to be expected as defined under the Child Death Review Procedures, then our Coroner liked to know in advance. So, we made all of those arrangements and let the family have their special private time together”. 

Kay reflects:
“We spent quite a few hours with Matthew – we called close family this time around. We didn’t get everybody coming from the far end of the country to be with Matthew. So, the time when Matthew did die, it was very, very peaceful. We had some quality time with him. We had a wonderful five weeks planning memories, planting memories for the other children and we spent those few hours reflecting on that and talking and supporting each other through the inevitable outcome of Matthew dying in the early hours of the morning.

We found that, when dealing with the professionals around Matthew’s death, that being able to change the wording of the Emergency Health Care Plan it kind of validated for us that what we wanted … we wanted Matthew to be peaceful and at home when he died, surrounded by his toys and his family. We felt that the Plan, when we read the wording of it, was quite a shock to see that he should be allowed to ‘die with dignity’ but it validated what we were feeling, that it gave us permission to ask that he could die at home where we wanted him to be. It made us feel that we weren’t asking for anything that was out of the ordinary or not possible and felt that we were actually more in control of the situation when the time actually came for Matthew to pass away”. 

Achieving a supporting a child or young person through a good death is an important part of our job, when death is inevitable. We need to ensure we always steer the best possible course through the tricky waters of decision-making, protecting the rights of all children and young people to the best possible outcomes.

So, back to the key messages

  • Every child’s life matters.
  • Always listen to the child, their parents and those who know the child best and include them in best-interests decision-making.
  • Always make decisions within an ethical framework and record the process of decision-making and who was involved.
  • Ensure that pathways are in place to record and make visible best-interests’ decisions about levels of intervention.

If you want to read more about advance care planning, look at:

Horridge KA. Advance Care Planning: practicalities, legalities, complexities and controversies. Arch Dis Child. 2015;100:380-385

If you want to see and hear examples of the conversations that underpin advance care planning, more free e-learning can be found here:

https://councilfordisabledchildren.org.uk/our-work/health-and-wellbeing/practice/emergency-healthcare-plans

To listen to discussions between paediatricians and a parent about signs of sepsis in disabled children, tune in to Episode 4 of the RCPCH sepsis podcast series here.

Thank you for your time and all the best for your advance planning and decision-making.

Hirschsprung Associated Enterocolitis

Cite this article as:
Peter Tormey. Hirschsprung Associated Enterocolitis, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.28496

Michelle is a 5-year-old girl with a background of Hirschsprung’s Disease. She had a pull through procedure performed 6 months ago. She is on daily PR washouts.

She presents to ED acutely unwell with multiple episodes of brown vomiting. On examination she is lethargic, grey in colour and peripherally shut down. Her abdomen is distended.

What is Hirschprung’s Disease?

Hirschprung’s Disease (HD) is caused by the failure of neural crest cells to migrate completely during intestinal development.

The neural crest cells are progenitor cells for the enteric nervous system, which controls peristalsis, blood flow to the gut and secretions. The enteric ganglia are interconnected to form 2 plexi that extend along the length of the bowel: an out myenteric (Auerbach) plexus running the full length of the gut and an inner submucosal (Meissner) plexus, found in the small and large intestine. The absence of these plexi results in an aganglionic segment of colon, which fails to relax, causing a functional obstruction.

Interestingly, the timing of the arrest in migration of the neural crest cells influences the severity of disease. The cells migrate in a craniocaudal fashion, therefore, early arrest results in a longer segment of aganglionosis.

The incidence of HD is 1 in 5000 live births. The male-to-female ration is 4:1 in short segment disease but it is 1:1- 2:1 in long segment disease.

How do children with Hirschprung’s present?

How these children present depends on whether they have short or long-segment disease. Short-segment disease only involves the rectosigmoid colon and accounts for 80-85% of cases. In long-segment disease, the aganglionosis extends proximally to the sigmoid colon.

Those with long-segment disease are more severely affected and tend to present earlier, usually in the first few days after birth. They can present with any of the following features:

  • Abdominal distension
  • Bilious vomiting
  • Delayed passage of meconium
  • Enterocolitis

Those with short-segment disease may present later in childhood with constipation and failure to thrive.

What is “delayed” passage of meconium?

There is a big variation in the timing of first meconium passage in neonates, however, most healthy newborns will pass stool within the first 24 hours. All healthy newborns should pass their first stool within 48 hours.

Clark studied 395 term infants and found that 98.5% of them passed stool within the first 24 hours and 100% within 48 hours.

It is generally acknowledged that term infants who don’t pass stool within the first 48 hours should undergo careful evaluation and investigation. 60-90% of patients with HD will not pass meconium within 48 hours.

The differentials of delayed passage of meconium are listed below:

  • Meconium plug syndrome
  • Meconium ileus
  • Hirschsprung’s disease
  • Anorectal malformation
  • Intestinal atresia
  • Malrotation, volvulus
  • Hypoplastic left colon syndrome
  • Opioid use
  • Hypothyroidism
  • Sepsis
  • Prematurity, low birth weight

Hirschprung Associated Enterocolitis

Hirschsprung Associated Enterocolitis (HAEC) is a serious complication of HD. Patients can present critically unwell with haemodynamic instability, fever, vomiting, explosive diarrhoea and abdominal distension. An explosive release of gas or stool during rectal examination strongly supports a diagnosis of HD.

The incidence of HAEC ranges from 6-60% prior to pull-through surgery and 25-37% after surgery. HAEC can be potentially life-threatening. Swenson was one of the first to report on mortality in HAEC, reporting a mortality rate of 33% after HAEC, compared with 4% in HD patients without EC. The reported mortality in other studies varies greatly from 0 to 39%.

Mortality rates have improved in recent years, most likely due to improved supportive care in PICU and improved surgical expertise. The mortality rate in HAEC is now 1%.

Poor prognostic factors are: HAEC present at diagnosis of HD and postoperative HAEC.

While it can be seen in all children with HD, several features appear to be associated with an increased risk:

  • Trisomy 21
  • Long-segment disease
  • Previous HAEC
  • Post-op obstruction

The cause of HAEC is unknown. Several hypothesis have been proposed:

  • Dysbiosis of the intestinal microbiome
  • Impaired mucosal barrier function
  • Altered innate immune response
  • Bacterial translocation

Mild cases can present with symptoms of viral gastroenteritis, fever, mild abdominal distension and diarrhea. If it is not promptly recognized and treated it can progress to toxic megacolon, which can be fatal. 

It is important to remember that HAEC can also occur in children who have had surgical repair for HD. It is due to obstruction, which can be due to:

  • Retained aganglionosis
  • Transition zone pull-through
  • Dysmotility following pull-through
  • Anastamotic stricture

A high index of clinical suspicion is required to make the diagnosis. Abdominal x-ray is also helpful and usually shows significantly dilated bowel loops and air-fluid levels.

HAEC is an emergency. Prompt treatment is required with IV antibiotics, (e.g metronidazole, gentamicin, amoxicillin) fluid resuscitation and surgical evaluation, which may include rectal washouts or an emergency colostomy.

Which children with constipation do we need to worry about?

Constipation is a very common presentation to ED. When assessing these patients it is important to screen for any underlying abnormalities, including HD.

Constipation, with the following features should raise your suspicions for undiagnosed HD:

  • Neonates
  • History of delayed passage of meconium
  • Chronic, refractory constipation
  • Failure to thrive
  • Presence of other urogenital abnormalities
  • Family history of HD (the risk for a sibling is 200 times higher than the general population, (4% vs. 0.02%)
  • Associated syndromes:
    • Down Syndrome
    • Bardet-Biedl syndrome
    • Cartilage-hair hypoplasia
    • Congenital central hypoventilation syndrome
    • Multiple endocrine neoplasia type 2
    • Mowat Wilson syndrome
    • Smith-Lemli-Opitz syndrome
    • Waardenburg syndrome

How is Hirschprung’s diagnosed?

Abdominal x-ray may show dilated bowel loops, thickened bowel loops or air fluid levels. These findings, however, are non-specific.

Contrast enema is useful to demonstrate the functional obstruction seen with HD, as seen in the film below.

Contrast study demonstrating a stenotic segment in the sigmoid colon with dilation of the descending colon.
Case courtesy of Dr Mohammad Farghali Ali Tosson. From the case https://radiopaedia.org/cases/50255 rID: 50255

Definitive diagnosis is by rectal suction biopsy.

It is important to consider HD in children presenting to ED with constipation. You should have a low threshold for surgical referral, particularly if they have any risk factors listed above.

How is Hirschprung’s treated?

Treatment involves surgical resection of the aganglionic segment and anastomosis of the normal bowel to the anus, while preserving sphincter function.

Long term complications include:

  • Chronic constipation
  • Incontinence
  • Recurrent HAEC
  • Psychosocial issues

Did you know?

HD was first described by Harald Hirschsprung in 1886. He described 2 children with severe constipation, due to dilation and hypertrophy of the colon.

Lennander in 1900 was the first to suggest that the pathogenesis may be neurogenic in origin. Tittel then demonstrated in 1901 histiological findings indicating aganglionosis of the colon. In 1948 Swenson used motility studies to demonstrate absence of peristalsis in the aganglionic colon.  

The history of Hirschsprung’s Disease is an interesting and colourful one with many false starts and conflicting opinion. If you’re interested in reading more, look no further than this American Academy of Surgeons history of surgery article.

Michelle was fluid resuscitated and commenced on IV antibiotics. She was transferred to PICU due to haemodynamic instability. She was managed conservatively by the surgical team with regular rectal washouts.

Michelle has had several episodes of HAEC previously. This episode, in particular, was life-threatening. Her parents are finding it harder to perform the daily rectal washouts as she gets older. As a result, it was decided to perform an ileostomy to improve bowel management and to try and prevent HAEC.

References

1. Butler Tjaden NE, Trainor PA. The developmental etiology and pathogenesis of Hirschsprung disease. Vol. 162, Translational Research. Mosby Inc.; 2013. p. 1–15.

2. Congenital aganglionic megacolon (Hirschsprung disease) – UpToDate [Internet]. [cited 2020 Jul 7]. Available from: https://www-uptodate-com/contents/congenital-aganglionic-megacolon-hirschsprung-disease?search=hirschsprung disease children&source=search_result&selectedTitle=1~76&usage_type=default&display_rank=1

3. Haricharan RN, Georgeson KE. Hirschsprung disease. Semin Pediatr Surg [Internet]. 2008 Nov [cited 2020 Jul 20];17(4):266–75. Available from: https://pubmed.ncbi.nlm.nih.gov/19019295/

4. Ryan ET, Ecker JL, Christakis NA, Folkman J. Hirschsprung’s disease: Associated abnormalities and demography. J Pediatr Surg [Internet]. 1992 [cited 2020 Jul 20];27(1):76–81. Available from: https://pubmed.ncbi.nlm.nih.gov/1552451/

5. Clark DA. Times of First Void and First Stool in 500 Newborns [Internet]. Vol. 60, PEDIATRICS. 1977 [cited 2020 Jul 28]. Available from: www.aappublications.org/news

6.Loening-Baucke V, Kimura K. Failure to Pass Meconium: Diagnosing Neonatal Intestinal Obstruction. Am Fam Physician. 1999 Nov 1;60(7):2043.

7. Gosain A, Frykman PK, Cowles RA, Horton J, Levitt · Marc, David ·, et al. Guidelines for the diagnosis and management of Hirschsprung-associated enterocolitis. Pediatr Surg Int. 2017;33:517–21.

8. Swenson O, Davidson FZ. Similarities of Mechanical Intestinal Obstruction and Aganglionic Megacolon in the Newborn Infant. N Engl J Med [Internet]. 1960 Jan 14 [cited 2020 Jul 28];262(2):64–7.

9. Vieten D, Spicer R. Enterocolitis complicating Hirschsprung’s disease. Semin Pediatr Surg. 2004 Nov 1;13(4):263–72.

10. Murphy F, Puri P. New insights into the pathogenesis of Hirschsprung’s associated enterocolitis. Pediatr Surg Int [Internet]. 2005 Oct 30 [cited 2020 Jul 28];21(10):773–9. Available from: https://link-springer-com.proxy.library.rcsi.ie/article/10.1007/s00383-005-1551-1

11. Badner JA, Sieber WK, Garver KL, Chakravarti A. A genetic study of Hirschsprung disease. Am J Hum Genet [Internet]. 1990 [cited 2020 Jul 20];46(3):568–80. Available from: /pmc/articles/PMC1683643/?report=abstract

12. Hirschsprung disease • LITFL • Medical Eponym Library [Internet]. [cited 2020 Jul 20]. Available from: https://litfl.com/hirschsprung-disease/

PEM Adventures Chapter 2

Cite this article as:
Team PEM Adventures. PEM Adventures Chapter 2, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.30926

Are you ready for another PEM adventure? This time the stakes are a little higher. Join us on another journey (with an inbuilt time travel machine) as we manage Grace…

Teenager holding mobile phone

Meet Grace. Grace is a 15-year-old vegetarian environmental activist. She’s thrilled because she’s recently hit a TikTok following of 10,000 – social media is SO the way to spread the word.

She spent yesterday at an illegal climate strike rally outside parliament. Buoyed up on the adrenaline of a thrilling protest, she and some buddies went back to her friend, Zak’s house where they celebrated in style with vodka pops. But this morning, horrified by the fact Grace was impossible to wake, Zak called the emergency services.

Meanwhile, you’ve just fished a pea out of a child’s ear when the red phone rings. Hearing the pre-alert, you mobilise the team and prep a bay in resus. Minutes later, Grace is wheeled in with Zak in tow and she’s transferred to a trolley.

Whiteboard containing vital signs

Your SHO, Lucy, does a primary survey:

  • A: Tolerating an oropharyngeal airway. No stridor or stertor.
  • B: Self-ventilating in 15L O2 via a non-rebreathe mask. Respiratory rate is a bit raised but her chest is clear and she doesn’t have any other signs of respiratory distress.
  • C: Warm and well perfused, heart rate 68 with normal heart sounds and normal pulse volume. Blood pressure is 115/70 and capillary refill time is less than 2 seconds.
  • D: GCS 7, made up of M4, V2, E1. Pupils are size 3 bilaterally and normally reactive to light. Tone is generally low but reflexes are normal and plantars are down going.
  • E: No rashes, no bruises and Grace is currently afebrile.

Lucy gets Grace’s mum’s number from Zak and phones her to get a bit more information. Grace is a healthy adolescent with no significant past medical history. She’s not on any medications, is not allergic to anything and is fully vaccinated. She’s been completely well with no fever, cough, coryza, or any other symptoms. She did have a cold sore a few months ago – could that be relevant?

Grace’s parents, who had gone away for the first time since covid-lockdown lifted, are running to the train station to make their way back home.

Back in resus, you put in a cannula, and send off some bloods: FBC, U&E, LFT, CRP, blood culture and an alcohol level.

Her venous gas shows a pH of 7.47, pCO2 of 2.7, bicarb 14, lactate of 2.7 and normal glucose.

Blood gases showing respiratory alkalosis

That’s odd, you think to yourself, a respiratory alkalosis with some metabolic compensation. You pause for a second and work through your list of possible causes.

  1. Could this be a central cause of hyperventilation? A bleed? A tumour? A meningoencephalitis? You put up a request for CT brain. 
  2. Could this be a respiratory cause? Asthma? Pneumonia? Pneumothorax? Better get a chest x-ray too.
  3. Could this be sepsis? You prescribe ceftriaxone and add acyclovir. There was that coldsore after all…
  4. Pregnancy?
  5. Endocrine or hypermetabolic cause? Maybe DKA? No… her blood sugar’s normal. Or thyrotoxicosis?
  6. Maybe it’s something toxicological? You remember, from your undergraduate days, learning that salicylates cause a respiratory alkalosis.

You add a salicylate level, and paracetamol for good measure, add thyroid function and ask for a catheter urine for beta HCG and a tox screen.  

But her catheter urine doesn’t give you any extra clues. Grace’s urine beta-HCG is negative, her tox screen is negative and her dip is negative.

The resus nurse gently touches your elbow and quietly says, “Do you want to call the anaesthetist?

Good question, you think to yourself. Her GCS is 7 and she’s tolerating the oropharyngeal airway, but she’s breathing well for herself at the moment. What do you want to do?

There are some compelling arguments not to intubate; Grace is maintaining her airway and she’s obtunded and may have seizures – if you give her a paralysing agent as part of her RSI you’ll never be able to tell. Sure, if you really want to monitor for seizure activity, AND you’re in a a tertiary centre with a PICU with capability of CFM or EEG monitoring, you could keep arguing you can monitor for seizure activity while she’s intubated and ventilated, but it takes a while to set up, and time is of the essence.

So you make the brave decision not to intubate. 

You later decide it was less brave and more foolhardy. While Grace is in CT she drops her GCS further and then has a respiratory arrest, which quickly deteriorates into cardiac arrest. The scanner is a terrible place for CPR. While you’re trying to run an arrest on a narrow CT bed you wish you could go back in time and make that choice again. Luckily for you, the inbuilt PEM adventures time travel machine can do just that. In you hop and whizz back to resus.

Close the toggle and this time click on the ‘intubate’ choice.

There are some compelling arguments not to intubate; Grace is maintaining her airway and she’s obtunded and may have seizures – if you give her a paralysing agent as part of her RSI you’ll never be able to tell if she’s seizing. 

But there’s something niggling you… Grace is heading for a CT scan and the LAST thing you need is for her to arrest in the scanner.

And yes, it’s true, there is a risk you could miss a seizure if she was paralysed, but you can give her a long-lasting anticonvulsant to prevent seizures. 

So… you decide to follow your gut and make the decision to intubate.

Thankfully the anaesthetist is nifty with a tube and she’s already drawn up the RSI drugs – fentanyl, ketamine and rocuronium in a 1:1:1 ratio (that’s fentanyl 1mcg/kg, ketamine 1mg/kg and rocuronium 1mg/kg). She’s intubated without difficulty. 

Grace has bilateral equal breath sounds and a mobile chest x-ray shows the tube to be in a good position, with clear lung fields and normal heart size. You mentally cross respiratory causes of an alkalosis off your list.

You’re doing great.

The anaesthetist asks you, “How should I ventilate Grace? Should I match her raised respiratory rate?

That’s a good question, you think to yourself. What should you do?

This is a very good question and you’re not sure you know the answer. Grace is hyperventilating for some reason, and maybe mimicking this is the right thing to do…

But, you’re worried about her ultra low pCO2. At 2.7 it’s likely to be causing cerebral vasoconstriction and hypoperfusion. It’s time to start some simple, proactive neuroprotective measures.

On reflection, you decide it would be better to slow Grace’s breathing so resolutely you turn back to the anaesthetist and ask him to SLOW Grace’s respiratory rate to keep her end tidal CO2 tightly between 4.5 and 5; you want to prevent secondary brain injury.

He nods his assent, while tilting the head of the bed up to 30 degrees.

But, remembering a great DFTB post by Costas Kanaris, you know you can do more than that to neuroprotect. As well as maintaining normocapnia and nursing her at 30 degrees head in line, Grace needs strict normothermia and hypoxia should be avoided at all costs. She needs vigilant glucose monitoring, tight circulatory monitoring and support and an anticonvulsant to prevent seizures. 

Close the toggle and move on to the next part of the story.

You think this through. The alkalotic pH doesn’t matter quite so much, what’s really troubling you is Grace’s pCO2. With a pCO2 of 2.7, there’ll be huge amount of cerebral vasoconstriction and hypoperfusion. It’s time to start some simple, proactive neuroprotective measures.

Resolutely you turn back to the anaesthetist and ask him slow Grace’s respiratory rate to keep her end tidal CO2 tightly between 4.5 and 5; you want to prevent secondary brain injury and so now’s the time to start some neuroprotection.

He nods his assent, while tilting the head of the bed up to 30 degrees.

But, remembering a great DFTB post by Costas Kanaris, you know you can do more than that to neuroprotect. As well as maintaining normocapnia and nursing her at 30 degrees head in line, Grace needs strict normothermia and hypoxia should be avoided at all costs. She needs vigilant glucose monitoring, tight circulatory monitoring and support and an anticonvulsant to prevent seizures. 

Great choice! Close the toggle and move on to the next part of the story.

With fortuitous timing, CT ring down to say they’re ready for Grace.

Satisfied that A, B and C are all stable, you turn to take the brake off the trolley when Lucy, your SHO, asks, “But do we only want a plain non-contrast CT?

That’s a good question, you think to yourself. Is that all I want? What neuroimaging will you choose?

“Yes”, you say to Lucy. “A non-con CT is quick and will show us most tumours and bleeds. She can have an MRI later to get a bit more detail.” 

But,” your SHO counters, “a non-con CT won’t always detect an ischaemic stroke. Perhaps we should ask for a CTA too?

You remember a case from a few weeks ago, a little boy called Tomas. You’d bookmarked the RCPCH Stroke in Childhood guideline on your phone. You quickly bring it up and Lucy’s right, the guideline says to consider stroke in children with focal neurology, speech disturbance, focal seizures, severe headache, cerebellar signs… and unexplained decreased conscious level.

Smiling gratefully at Lucy you pick up the phone and ask the radiologist if you can add a CTA. They say yes.

Minutes later, Grace has her CT with CTA… but it’s normal. No abscess… no tumour… no bleed… and no stroke.

Well that’s good news for Grace, you think to yourself, but it doesn’t give you any much-needed clues.

Great work. Close the toggle and move onto the next part of the story.

You know what”, you say to your SHO, “let’s ask for a contrast-enhanced CT. It’s still quick and will give us a little more detail than a non-con CT.

But,” she counters, “do you think we should be considering stroke in our differential? Perhaps we should ask for a CTA too?

You remember a case from a few weeks ago, a little boy called Tomas. You’d bookmarked the RCPCH Stroke in Childhood guideline on your phone. You quickly bring it up and Lucy’s right, the guideline says to consider stroke in children with focal neurology, speech disturbance, focal seizures, severe headache, cerebellar signs… and unexplained decreased conscious level.

Smiling gratefully at Lucy you pick up the phone and ask the radiologist if you can add a CTA. They say yes.

Minutes later, Grace has her CT with CTA… but it’s normal. No abscess… no tumour… no bleed… and no stroke.

Well that’s good news for Grace, you think to yourself, but it doesn’t give you any much-needed clues.

Great work. Close the toggle and move onto the next part of the story.

You know what”, you say to your SHO, “let’s ask for a CT plus CTA. The CT will show us most tumours and bleeds and she can have an MRI later for a bit more detail, but we should consider stroke in our differential, and to detect that we need to add angiography to our CT.

You think back to a case from a few weeks ago, a little boy called Tomas. You’d read the RCPCH Stroke in Childhood guideline and remember that it says to consider stroke in children with focal neurology, speech disturbance, focal seizures, severe headache, cerebellar signs… and unexplained decreased conscious level.

Smiling gratefully at Lucy you pick up the phone and ask the radiologist if you can add a CTA. They say yes.

Minutes later, Grace has her CT with CTA… but it’s normal. No abscess… no tumour… no bleed… and no stroke.

Well that’s good news for Grace, you think to yourself, but it doesn’t give you any much-needed clues.

Great work. Close the toggle and move onto the next part of the story.

You haven’t ruled out infection. So, when you’re back down in resus, you ask Lucy if she’d like to do the LP.

Really? Is that safe with her low GCS?” she questions. 

What do you think? Should you LP?

It’s fine,” you reply, “she doesn’t have physiological signs of raised ICP: she’s not bradycardic or hypertensive, she’s not posturing and she didn’t have focal neurology. Plus, her CT doesn’t look like there’s cerebral oedema.

Feeling reassured, Lucy picks up the spinal needle and performs an LP. 

But it’s not your finest decision. Grace cones and arrests. 

Luckily for you and Grace, there’s an inbuilt time travel function in your PEM adventure and you return back to resus just as your SHO asks if it’s safe to LP Grace.

You have a strange feeling of déjà vu, while a little voice tells you that although a normal CT is usually reliable for ruling out raised intracranial pressure, this isn’t failsafe and it might be safer to defer the LP for when she’s a little more stable. You’ve already started the ceftriaxone and acyclovir, so this time you decide that the LP can wait until she’s a bit more stable and can have an MRI first. 

Thank goodness for that time machine! Close this toggle and move onto the next part of the story.

Lucy’s right. Although a normal CT is usually reliable for ruling out raised ICP, this isn’t failsafe and there’s no rush to get CSF now. You’ve already started ceftriaxone and acyclovir anyway. And when she’s a bit more stable she can have an MRI to check the LP’s safe. The LP can wait for now.

Great teamwork! Close the toggle and continue the next part of the story.

You’re still not sure what’s causing Grace’s low GCS though. Maybe the bloods will help. So you log in to the computer to check Grace’s results.

Results showing a mild transaminitis

Huh, you think to yourself. Grace’s FBC and CRP are normal; it’s sounding less and less like infection.

Her urea is low and her liver enzymes are raised, with a slightly prolonged INR.

Her salicylate and alcohol levels are undetectable. This isn’t feeling so toxicological anymore.

You mull this over with Lucy. Maybe this is a viral picture. There was that cold sore…

Just then Maureen, the ED cleaner, pops her head into the office. “Might this be of any use?” she asks. She’s holding the RCPCH Decreased Conscious level guideline.

You quickly flick through. Bloods… imaging… you’ve done pretty much everything it suggests. But then you take a closer look at the list of bloods it suggests. And there, in black and white, it says ammonia.

Of course!” you say out loud. “That would explain the respiratory alkalosis!

You draw off an ammonia sample, get it on ice and ask Raymond, the dashing porter, to run it down to the lab. You give the lab a ring so they can get the machine primed.

While you’re waiting for the result to come back, Zak comes running over. He’s just been looking in Grace’s backpack for her mobile and found a high protein Diet book. Apparently she’s been trying to lose weight for TikTok. Could it be relevant?

The cogs begin to whir… Hang on a minute… A high protein diet in a vegetarian environmental activist?

The lab phones with Grace’s ammonia level.

It’s over 500! And normal is less than 40.

It all falls into place. Selective vegetarian… Recent protein load… Raised transaminases… High ammonia… This is all beginning to sound a bit metabolic.

But what should you do about that ammonia? As far as you can see, the DeCon guidance only tells you to take it, not what you do when it comes back at over 10 times the upper limit of normal.

Just a sec,” says Lucy scrolling through her mobile phone, “The British Inherited Metabolic Disease Group have got this covered. They’ve produced a whole range of easy access emergency guidelines, including this one, for the management of an undiagnosed hyperammonaemia.”

It says, turn off protein catabolism by giving a 10% dextrose bolus followed by a dextrose infusion to provide an alternative energy source. If her glucose climbs, add insulin but don’t reduce the dextrose – otherwise, she’ll just start breaking down more protein. And, finally, mop up that ammonia with scavengers like phenylbutyrate and sodium benzoate.

The words ‘ammonia scavengers’ remind you of another post you read on Don’t Forget The Bubbles, about the different types of metabolic conditions, how they present and the various treatment strategies. You make a mental note to read it again later to remind yourself of the differences between an amino acid and organic acid.

Meanwhile, you hastily prescribe…

  •       A 2ml/kg bolus of 10% dextrose
  •       a dextrose infusion
  •       And those ammonia scavengers, sodium benzoate and sodium phenylacetate

Grace is subsequently diagnosed as having a urea cycle disorder. You’re amazed to discover that although most diagnoses are made in neonates, diagnoses are sometimes made in adolescents and adults presenting encephalopathic after a big protein load or when catabolic, such as after trauma, childbirth, major surgery, major haemorrhage, critical illness, rapid weight loss or simply after switching to a high protein diet. This is particularly true for ornithine transcarbamylase (OTC) deficiency, which although is X-linked, can present in symptomatic female OTC carriers. Little diagnostic clues include autoselective vegetarianism (that protein makes them feel a bit ‘ugh’) and subtle or behavioural difficulties from chronic low-level hyperammonaemia.

You bookmark a fantastic review article to read later and flick back through your undergraduate biochemistry textbook to remind yourself about urea cycle defects… and hastily close it again when you remember how little you knew even then, at the prime of your undergrad years.

Wow, what a shift. You pack up your stethoscope and head home, reflecting on your day as you walk to the bus stop.

Grace has taught you the importance of…

Reaching for the RCPCH DeCon guideline when looking after a child with an unexplained low GCS.

Not ever forgetting to send an ammonia in an encephalopathic child, young person or even adult; these tricksy urea cycle disorders can present in adulthood. If the ammonia comes back high, BIMDG have a handy guideline telling you exactly what to do.

And, remembering that a normal CT does not ALWAYS rule out raised ICP. In a child with low GCS, put away that LP needle and neuroprotect instead.

But what happened to Grace? Let’s jump in the time travel machine and find out…

Your epic diagnosis of a late presenting metabolic disorder was the talk of the ED. The RCPCH DeCon poster was put up in the ED staff room and from that point onwards, everyone remembered to check an ammonia in a patient presenting with an unexplained low GCS. 

Lucy was nominated as employee of the month. This shift was a pivotal moment in her career as she decided PEM was her vocation.

The ammonia scavengers did the trick and Grace made a full recovery.

Grace focussed her efforts on reducing plastic waste in hospital and successfully petitioned for the introduction of plastic-free PPE, reducing plastic waste during the COVID-19 pandemic by an incredible 275%.

She hit 3 million TikTok followers (and you’re one of them).

This PEM adventure wouldn’t have been possible without some help from some amazing people. Thank you to Roshni Vara, Consultant in Paediatric Inherited Metabolic Disease at the Evelina London, Costas Kanaris, PICU and retrieval consultant at the Royal Manchester Children’s Hospital and Jon Lillie, PICU and retrieval consultant at the Evelina London Children’s Hospital.

Here are some of their wise words of advice…

As Costas says in The N of 1 matters, we’ve outlined our take on Grace’s case and how we’d manage her in our own resus bays. Medicine’s not always so clear cut and there are often different approaches to the same problem, but this is our consensus on minimising risk using, as Costas says, a rational, evidence-based and pharmacologically prudent approach (I love that phrase Costas!)

Should we intubate Grace?

Grace is self-ventilating but the fact that she is tolerating an oropharyngeal airway means some of her airway reflexes have gone. Scanning a child with a GCS of 8 or less, without securing the airway, puts them at risk. If they vomit, they aspirate. If they stop breathing and arrest in the scanner, the CT room is one of the least fun places to run an arrest, perhaps second only to an elevator. Are there any counter-arguments? Yes, and they’re soft.  One is “this patient is encephalopathic/obtunded and may have seizures; if the child starts fitting we won’t be able to tell as they’ll be paralysed”.  Costas says he usually stands his ground and says that if someone is worried about seizures then the child can be given a long-acting antiepileptic. Levetiracetam is his preference, although phenytoin would work just as well unless there’s suspicion of an overdose of an arrhythmogenic agent. The last thing you need is to tip this child into an arrhythmia.

When should a lumbar puncture be performed in a child with a decreased conscious level?

CT is a useful tool for ruling out raised intracranial pressure before proceeding to lumbar puncture. And we’d agree. But Grace has a low GCS and this changes the picture.

If we take a look at the full RCPCH DeCon guideline it dedicates a whole section to answering the question about LP in decreased conscious level. So, let’s start there.

The DeCon guideline advises a lumbar puncture if your differentials are viral encephalitis or tuberculous meningitis and advises that we consider lumbar puncture when our differentials are bacterial meningitis, sepsis, or the cause of the low GCS is not known. This is cloaked with the phrase “when no acute contraindications exist” and this is key. So what are those contraindications?

  • Signs of raised intracranial pressure: dilated pupil(s), abnormal pupil reaction to light, bradycardia, hypertension or abnormal breathing pattern.
  • A GCS equal to or less than 8, or a deteriorating GCS
  • Focal neurology
  • A seizure lasting more than 10 minutes with a GCS less than 13
  • Shock or clinical evidence of meningococcal disease
  • CT or MRI suggesting obstruction of the CSF pathways by blood, pus, tumour or coning.

What’s the evidence? Well, it’s mostly been derived by expert opinion, and there aren’t many people who’d dispute them.

But what about when you have a normal CT? The radiologists can look for midline shift and for signs of impending herniation by assessing the position of the cerebellar tonsils. So, surely that can rule out raised ICP, allowing an LP to be done?

The DeCon guideline quotes a study published in 2000 that showed that in 124 CT scans from 65 children with traumatic brain injury, CT had an excellent sensitivity of detecting raised ICP of 99.1%, with a specificity of 78.1%. But, a 2019 revision to the guideline says that no further evidence about the sensitivity or specificity of CT in detecting raised ICP in children has been found. None. Although the sensitivity in the one quoted study was very high, it was felt that one study, in children with traumatic brain injury, could not be extrapolated to all children with a decreased conscious level. And so the guideline states that a normal CT scan does not exclude raised ICP. If other contraindications are present, don’t use a normal CT to justify LP.

What does this mean in practice? Well, in a child with a GCS of 8 or less, like Grace, there’s no rush to do an LP. It’s unlikely to change your management acutely in the ED. Her infection can be treated empirically and once she’s more stable, and you have more information including, potentially, an MRI, she can then have an LP for PCR.

What neuroimaging should we do?

That’s a good question, answered beautifully by an article by Hayes et al, published in 2018. Although this article focuses on neuroimaging for headaches, it has a great section on when you might choose each type of scan.

We’d all agree that the ideal imaging to look for a brain tumour is an MRI. It gives excellent detail about the brain tissue as well as other intracranial soft tissues and the extra-axial CSF spaces.

But, if you want a quick answer, or your access to MR is difficult, a non-contrast CT can be performed easily from the ED. If there’s no possibility of a later MR, then contrast-enhanced CT might be better as it gives more detail, but it’s more radiation – this is one for discussion with the radiologist.

CT is very sensitive in detecting blood, and it can be done quickly, in an emergent setting from the ED. So, in children with thunderclap headache, when you want to exclude subarachnoid hemorrhage, a non-contrast CT will be your first choice scan. If blood is detected, then add in arterial imaging: CT or MR angiography (CTA or MRA). Contrast is injected and images taken in the arterial phase.

CTA or MRA are also useful in the investigation of suspected stroke. In practice, you need an answer fast, particularly if the child’s within the thrombolysis window and could be a candidate if there’s evidence of ischaemic stroke, so a CTA is a more practical scan. The CT component looks for blood or large areas of parenchymal infarct, while the angiography looks for filling defects in the arteries that could indicate a thrombus.

If you’re looking for intracranial extension of infection, such as from an orbital cellulitis, mastoiditis or a brain abscess, then a contrast-enhanced CT will highlight suppurative collections.

And if you suspect a venous sinus thrombosis, such as in children with coagulopathies, sickle cell disease, infective spread from meningitis / mastoiditis / sinusitis, or secondary to dehydration or renal failure? Then you need to look at the venous spaces. CT or MR venography (CTV or MRV), when contrast is injected and images obtained in the venous phase, will give you the answers you need.

And what ARE the causes of a respiratory alkalosis?

There are a few! Here are the main ones:

  • Central: brain tumours, meningoencephalitis; stroke
  • Respiratory: asthma, pneumonia, pneumothorax, PE
  • Sepsis
  • Pregnancy
  • Endocrine and hypermetabolic cause: DKA, thyrotoxicosis
  • Toxicology: salicylates 
  • Hyperammonemia: liver and metabolic disorders 
infographic of causes of respiratory alklosis

We would LOVE your feedback about these DFTB PEM adventures so if you can spare a minute, please complete our survey at www.tiny.cc/DFTBpemadventure or use your smartphone to let the QR code take you straight there. We timed ourselves completing it and it takes less than a minute. Thank you.

Select references

The management of children and young people with an acute decrease in conscious level. A nationally developed evidence-based guideline for practitioners. RCPCH. 2015 update, with 2019 revisions. Management of children and young people with an acute decrease in conscious level – Clinical guideline | RCPCH

Undiagnosed Hyperammonaemia. Diagnosis and Immediate Management. British Inherited Metabolic Disease Group. Last reviewed 2017. The major causes are as follows (bimdg.org.uk)

Hirsch, W., Beck, R., Behrmann, C. et al. Reliability of cranial CT versus intracerebral pressure measurement for the evaluation of generalised cerebral oedema in children. Pediatric Radiology 30, 439–443 (2000). https://doi.org/10.1007/s002470000255

Expert Panel on Pediatric Imaging:, Hayes LL, Palasis S, Bartel TB, Booth TN, Iyer RS, Jones JY, Kadom N, Milla SS, Myseros JS, Pakalnis A, Partap S, Robertson RL, Ryan ME, Saigal G, Soares BP, Tekes A, Karmazyn BK. ACR Appropriateness Criteria® Headache-Child. J Am Coll Radiol. 2018 May;15(5S):S78-S90. doi: 10.1016/j.jacr.2018.03.017. PMID: 29724429.

Mitani H, Mochizuki T, Otani N, Tanaka H, Ishimatsu S. Ornithine transcarbamylase deficiency that developed at the age of 19 years with acute brain edema. Acute Med Surg. 2016;3(4):419-423. doi:10.1002/ams2.214

Summar ML, Barr F, Dawling S, Smith W, Lee B, Singh RH, Rhead WJ, Sniderman King L, Christman BW. Unmasked adult-onset urea cycle disorders in the critical care setting. Crit Care Clin. 2005 Oct;21(4 Suppl):S1-8. doi: 10.1016/j.ccc.2005.05.002. PMID: 16227111.

Kanaris C, Ghosh A, Partington CG389(P) A case for early ammonia testing in all encephalopathic patients: female patients with x-linked ornithine transcarbamylase deficiency. Archives of Disease in Childhood 2015;100:A158-A159. http://dx.doi.org/10.1136/archdischild-2015-308599.343

Summar, Marshall. (2005). Presentation and management of urea cycle disorders outside the newborn period. Critical Care Clinics. 21. IX-IX. 10.1016/j.jccc.2005.08.004.

Shoulder x-ray interpretation

Cite this article as:
PJ Whooley and James Foley. Shoulder x-ray interpretation, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.29653

Don’t be bamboozled by a paediatric shoulder x-ray. Use an ABCD approach and pick up some tips and tricks in our step-by-step guide.

A – An adequate x-ray 

Is it the right patient and do you have the 2 views you want to see? The typical views are AP (external rotation) and the scapular Y view. (Not sure why then thisx meme may help).  Occasionally an axillary view is added to assess for dislocations and glenohumeral instability. 

B – Bones

Go through the bones one at a time. Follow the cortex of every bone in each view. Look for a disruption or a buckle in the cortex or any fracture fragments. They should all be smooth.  

  • The clavicle is a good bone to start with – it is by far the most common paediatric shoulder injury. Midshaft fractures account for 80% of clavicle fractures. Make sure there are no distal or medial fractures as they can often be subtle. 
  • Move onto the proximal humerus – check the epiphysis and metaphysis. A normal humeral head looks like a walking stick on the AP view. The most common fracture of the humerus is a metaphyseal fracture. Metaphyseal fractures occur in ages 5-12 and Salter-Harris fractures outside of this range. 
  • Don’t forget the scapula, seen best on the Y view. Management is conservative but a fracture here indicates a significant trauma. 

Like the paediatric elbow, the paediatric shoulder has ossification centres, so x-ray appearances differ depending on the age of the child.

At birth, the humeral diaphysis, mid position of clavicle and the body of the scapula are ossified – the rest are essentially cartilage.

The proximal humerus has three ossification centres:

  • Head – 1 year of age
  • Greater tubercle – 3 years
  • Lesser tubercle – 5 years

  • The scapula has 7 secondary ossification centres. 
Ossification centres of the scapula

Look carefully for the following two – if they appear early they may be the only sign of an avulsion fracture:

  • The sub-coracoid ossificiation centre appears between 8 to 10 years and completely fuses between 16 and 17 years of age, forming the upper third of the glenoid articular surface . If it appears before the age of 8, this may indicate an avulsion (pulled by the long head of biceps at its attachment to the superior glenoid). 
  • The inferior glenoid ossification centre, appears at the lower two-thirds of the glenoid articular surface. It grows and fuses to form a horseshoe shaped epiphysis that combines with glenoid rim and sub-coracoid ossification centre. This appears between 14 and 15 years (although sometimes as young as 11 years), with complete fusion by 17 to 18 years. It can be difficult to view on standard radiographs but sometimes it can be seen on the Grashey (AP oblique) view 

A top tip: If you are unsure whether what you are seeing is an avulsion fracture or a simple ossification centre, then press directly on the patient where the fragment is. If this isn’t painful then it is highly likely to be an ossification centre and not an avulsion. Range of movement is another great give-away – it is quite hard to have an avulsion fracture and intact range of movement! If in doubt, speak to a friendly radiologist (in hours) or be conservative and place in an arm sling and bring back to clinic (out of hours) for re-assessment (when the x-ray will have been reported).

Don’t forget the other bones that don’t make up the shoulder. Have a look for rib fractures, and if you see old healing rib fractures then consider non accidental injury.

C – Connections & Connective Tissue

Are all the bits connected to where they should be? Ask yourself a few questions when you’re looking at the different joints.

Glenohumeral joint:

  • Do the articular surfaces of the humerus and glenoid have 2 parallel lines with an even joint space?
  • Does the humeral head sit evenly on the glenoid in all views?
  • Does the humeral head sit adjacent to the glenoid on the AP view? Does it sit over the glenoid on the Y view? If the answers to these questions are no, and instead the humeral head is lying under the coracoid process, this indicates an anterior shoulder dislocation

Anterior Shoulder Dislocation (AP and Y views).The humeral head is located beneath the coracoid on the AP view and no longer located centrally on the Y view. In addition there is flattening of the humeral head suggesting a Hill Sachs lesion (more on this in the upcoming shoulder dislocation post)

  • Has the humeral head lost its characteristic walking stick appearance on the AP view? Does it instead look rounder, like a light bulb? If the answer to these questions is yes, this suggests a posterior shoulder dislocation.
  • Is there a joint effusion or lipohaemarthorsis present? This could indicate an intra-articular fracture of the glenoid or the humeral head. 
Case courtesy of Dr Garth Kruger, Radiopaedia.org. From the case rID: 21129

Acromioclavicular (AC) joint:

  • Does the bottom of the acromion lines up with the bottom of the distal clavicle? If there’s a step, think clavicle fracture or physeal injury
Normal alignment of the AC joint
  • Is there widening of the acromioclavicular joint (normal is 5-8mm) or coracoclavicular distance (normal is 10-13mm)? A widened AC joint > 8mm suggests an AC ligament rupture. If the coracoclavicular (CC)  distance is >13 mm consider CC ligament rupture. If you’re unsure, get weighted views of both AC or CC joints to compare each side (literally with the child holding weights in each hand to stress the joints).
AP view of shoulder

D – Don’t forget the other tissues

Always look around the area to look for foreign bodies or subcutaneous emphysema indicating a pneumothorax or pneumomediastinum. If there are, then a dedicated chest x-ray should be performed.

And finally, although the above may seem complicated, realistically common things are common.

  • Clavicle Fractures. By far the most common. 80% are mid-shaft and occur following a fall onto the outstretched hand or shoulder or direct trauma from a seatbelt or during sport.
  • Proximal humeral fractures. These occur in older children. 
  • Anterior shoulder dislocation. Usually in older children playing sports. Falls result in forced ABDuction, external rotation, and extension. Account for 95% of shoulder dislocations. 

Don’t miss

  • Acromioclavicular Joint injuries – widening or step at acromioclavicular joint and/or increased coraco-clavicular distance. 
  • Rib fractures – healing rib fracture? Consider NAI

References

  1. JS. Zember, ZS Rosenberg, S. Kwong, SP. Kothary, MA. Bedoya. Normal Skeletal Maturation and Imaging Pitfalls in the Pediatric Shoulder.  Radiographics. 2015 Jul-Aug;35(4):1108-22
  2. https://radiopaedia.org/articles/paediatric-shoulder-radiograph-an-approach

Metabolic presentations 3: Galactossaemia

Cite this article as:
Taciane Alegra. Metabolic presentations 3: Galactossaemia, Don't Forget the Bubbles, 2020. Available at:
https://doi.org/10.31440/DFTB.28602

It’s 11am on Easter Monday in Dublin. Emily is a 6 day old baby girl, born at 37 weeks via normal vaginal delivery across the Irish sea in Wales while her mother was visiting some friends. When Emily was 3 days old her mother returned to Ireland to stay with her own mother for some early baby support. Since day two of life Emily has been vomiting after feeding. She is bottle fed and since yesterday she has only been accepting half of each bottle. Her mother initially thought she was tired from the long trip but has brought her to the ED this morning because she has been quiet, hasn’t been crying as usual with nappy changes and seemed too sleepy to take this morning’s bottle. 

Emily was born in good condition by spontaneous vaginal delivery at 37/40. Her birth weight was 2.9kg. She was jaundiced on the second day of life, but below phototherapy levels. 

Social history: Emily’s parents are both healthy and from the Irish Traveller Community. 

Emily’s weight today is weight 2.45kg (a 16% drop below her birth weight). She’s jaundiced, lethargic, her anterior fontanelle is sunken, and Emily looks dehydrated. You can palpate the liver 2 cm below the right costal margin. No spleen palpable. Otherwise no positive findings. She’s afebrile with normal observations.

This baby has some red flags that will make anyone concerned. She is vomiting, lethargic, jaundiced, dehydrated, has hepatomegaly and has lost 16% of her birth weight. Emily is definitely sick. The list of potential diagnosis is extensive, but sepsis should always be the top of your list.

As you’re taking bloods for an FBC, U&E, LFT, ammonia and blood culture you’re told that Emily is hypoglycaemic so you collect additional bloods for a hypoglycaemia screen.

First, let’s correct the glucose!

Follow your local guideline regarding the initial investigation and management of hypoglycaemia and give 10% Dextrose 2mL/kg IV as soon as possible. 

Bloods should be be collected prior to treatment, but do not delay treatment due to problems collecting samples.

As this could be a metabolic presentation, instigate a generic management approach:

  • Clinical stabilisation
  • Antibiotics
  • Stop feeds
  • Give maintenance fluids with electrolytes to maintain hydration

The hypoglycaemia screen

The hypoglycemia workup should preferably be collected while the patient is hypoglycaemic, before giving glucose.

The basic screen aims to identify the most common endocrine or metabolic conditions responsible for hypoglycemia. Briefly, it involves: glucose, ketones (Beta-hydroxybutyrate), insulin, cortisol, Growth Hormone (GH), ammonia, lactate, free fat acids, serum amino acids, acylcarnitines profile (Guthrie card) and urine for organic acids and ketones. 

Discussing them in depth is beyond the scope of this post, but if you want to learn more, you can refer to this post by PaediatricFOAMed. 

Find out if your institution has a “hypoglycaemia kit” ready to go, as hypoglycaemia in a neonate can be a stressful situation that requires quick action. 

Emily’s blood sugar normalises. She has a full septic screen and is started on intravenous broad spectrum antibiotics. But, what’s her diagnosis?

Emily is hypoglycaemic with raised ketones, a normal response we would expect as she’s using fat as an alternative source of energy. However, in addition to this, Emily has hepatomegaly and raised liver enzymes, which together with hypoglycaemia, point towards a diagnosis of galactosaemia.

The worldwide incidence of classic galactosaemia is around  1:45,000 live births. Some countries screen for galactosaemia in their newborn screening programmes (Ireland, UK, New Zealand and some parts of Australia). Because of its autosomal recessive inheritance, galactosaemia is more common in some ethnic groups. 

In Ireland, around 1 in every 16,200 babies born each year may have galactosemia, however in the Irish Traveller community, this incidence is approximately 1 in 450 births, compared to only 1 in 36,000 in the non-traveller Irish population. Because of the high incidence in babies born to parents from the travelling community, these babies are specifically screened earlier, on day 1 of life, in Irish maternity hospitals.

High risk babies’ diets should exclude galactose, so newborn babies of Irish travelling families are given soy-based formula rather than breast feeds or standard formula until their screening test result is known.

A bit about galactosemia

As per definition, “galactosemia” refers to disorders of galactose metabolism that include classic galactosemia, clinical variant galactosemia, and biochemical variant galactosemia (Gene Reviews). The most common is classic galactosemia, an autosomal recessive disorder, that occurs due to a defect in the enzyme galactose-1-phosphate uridyl transferase (GALT), important in the transformation of galactose into energy.

Galactosemia presents after the affected patient receives the sugar galactose, present in milk. Accumulation of galactose-1-phosphate results in damage to the brain, liver, and kidney. The diagnosis is made by measuring the (GALT) enzyme activity (that will be low); by detecting elevated concentration of galactose-1-phosphate in erythrocytes (the substrate); or by testing if there are pathogenic mutations (two copies) in the GALT gene. The presence of a reducing substance in a routine urine specimen may be the first diagnostic clue.

Liver failure is a predominant finding in galactosemia and, besides that, the affected neonate presents with vomiting, hypoglycaemia due to an inability to metabolise glucose, feeding difficulty, seizures, irritability, jaundice, hepatomegaly, splenomegaly, cataracts and Escherichia coli sepsis

Treatment of the newborn requires the exclusion of all lactose sources from the diet, instead using lactose-free formulas. This must be started immediately after the disorder is suspected clinically, whilst awaiting screening results in high risk groups, or following a positive newborn screening results.

Interestingly, if the galactose-free diet is started early enough, the symptoms will disappear, jaundice will resolve within days, liver and kidney functions return to normal, liver cirrhosis may be prevented and cataracts may clear. 

Later in life…

Even patients treated from the very first few days of life can develop complications as they grow up. Galactosaemia represents a spectrum with symptoms varying from mild growth retardation, delayed speech development, verbal dyspraxia, difficulties in spatial orientation and visual perception, and mild intellectual deficit. Neuropsychological problems can appear during adolescence.  

Unfortunately, ovarian dysfunction is an almost inevitable consequence that can’t be prevented even by a strict diet. It is often seen early in infancy or childhood with hypergonadotropism. 

References

Berry JT. Classic Galactosemia and Clinical Variant Galactosemia In: Adam , HH. Ardinger, RA. Pagon, S. E. Wallis, L. J. H. Bean, K. Stephens, & A. Amemiya (Eds.), GeneReviews® [online book].

 Berry, JT, Walter JH, Fridovich-Keil JL. Disorders of Galactose Metabolism. In: Saudubray J-M, Baumgartner MR, Walter JH. (editors) Inborn Metabolic Diseases. Diagnosis and treatment. 6th Edition. Springer 2016. 

HSE. A Practical Guide to Newborn Bloodspot Screening In Ireland. December 2018. https://www.hse.ie/eng/health/child/newbornscreening/newbornbloodspotscreening/information-for-professionals/a-practical-guide-to-newborn-bloodspot-screening-in-ireland.pdf