Assessment and resuscitation of the shocked child is a complex and difficult topic even for those whose daily job it is to manage such situations. All the weirder, then, the college decision to include this specialised paediatric topic in their general adult intensive care examination process. It is unclear how detailed knowledge of this area identifies an adult intensivist as somebody deserving specialist-level accreditation. Certainly it enhances your practice, insofar as any medical knowledge does - but it is hard to argue that it forms a part of some sort of core body of essential knowledge.
Anyway, that rant is quite irrelevant. Paediatric shock is part of the curriculum. The shocked child has come up several times during the exam, in various variations:
These questions have had no specific focus. They tend to ask you to "outline the principles of management" or "early management". Candidates may be called upon to "list, in broad terms, the key differential diagnoses" and to produce some sort of diagnostic approach. Question 4 from the first paper of 2012 was distinct in its focus on hypovolaemia; it came in the wake of the 2011 FEAST trial. There was nowhere else to put a few lines about assessment of dehydration, so it ended up in this chapter.
In terms of answering such questions, it appears from the college model answers that an A-B-C-D approach was favoured. Very generic answers seem to have been supported. In fact the college answer for Question 10 from the first paper of 2015 even includes the phrase "General ICU housekeeping". Elsewhere, the college throw away marks by casually referring to an "ABCDEFG approach", which is something they constantly reprimand the candidates for doing.
Oh's Manual presents a series of lists for the assessment and recognition of shock, which are fairly commonsense. These lists are reproduced here with a few minor modifications.
Generic to the infant/paediatric population | ||
History
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Examination
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Investigations
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Specific for the neonatal population: | ||
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This was asked about in Question 10 from the first paper of 2015. They gave us a two week old baby who has been well after birth, and who has progressively deteriorated. The picture was of severe metabolic acidosis. What could this be, the college asked. Differentials are necessarily broad, and can be split into age categories. A table of suitably broad differentials is offered below. It does not come from any specific source.
Domain | Neonate/infant age group | Children older than 12 months |
Vascular |
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Infectious |
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Neoplastic |
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Drug-induced |
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Congenital |
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Autoimmune |
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Trauma |
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Endocrine or metabolic |
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Question 4 from the first paper of 2012 gave us a dehydrated child, and asked us exactly how dehydrated they were.. LITFL follows the college answer verbatim. Here it is, interpreted as a table:
Mild (5-6% loss of body weight) |
Moderate (7-10% loss of body weight) |
Severe (over 10% loss of body weight) |
2 or more of:
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2 or more of:
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That whole "two or more" thing comes from Gorelick (1997). "A subset of four factors—capillary refill >2 seconds, absent tears, dry mucous membranes, and ill general appearance—predicted dehydration as well as the entire set, with the presence of any two or more of these signs indicating a deficit of at least 5%". In general, when it comes to assessing dehydration, Gorelick et al recommend using a combination of three signs (this is also mentioned in the college answer) - a combination of three signs had a sensitivity of 87% and specificity of 82% for detecting a water deficit of 5% or more.
This is not the only possible dehydration assessment scale. The following table is slightly modified from Vega and Avner, by way of Steiner et al (2004). It is a list of clinical features which stratifies dehydration in young infants.
Mild
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Moderate
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Severe
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The Royal Children's Hospital give another, slightly different one:
Mild
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Moderate
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Severe
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Note the lack of "restlessness" and "also ask the parent". The pragmatic physicians from the RCH acknowledge the unreliability of subjective findings. At risk of inundating the candidate with more similar-looking dehydration assessment scales, one may merely refer to the popular Friedman (2004) which extends the pursuit of objective measurements further, extending the scale with urine output measurements, urinary specific gravity, specific heart rate ranges, and so forth.
This is an approach which supports undifferentiated shock presentations as described in the college answers. There needs to be a way for the candidate to appear confident and safe in managing generic issues while giving the appearance that they know exotic NICU interventions in significant detail. In other words, "assess the airway and the need for intubation" needs to appear in there somewhere, but apart from such sophomoric crap you also need to mention how you'll put that infant on an alprostadil infusion to keep their ductus arteriosus patent while you wait for their duct-dependent congenital defect to be repaired.
Working on the premise that all readers seriously preparing for this exam are going to "assess the airway and the need for intubation", here is a succinct list of important neonatal and paediatric caveats which need to be mentioned as a part of the answer:
The answer to a "describe your approach" question can use a familar A-B-C-D template. This approach was taken by the college in their model answer to Question 7 from the second paper of 2016.
Steiner, Michael J., Darren A. DeWalt, and Julie S. Byerley. "Is this child dehydrated?." Jama 291.22 (2004): 2746-2754.
Levine, Adam C., et al. "Empirically Derived Dehydration Scoring and Decision Tree Models for Children With Diarrhea: Assessment and Internal Validation in a Prospective Cohort Study in Dhaka, Bangladesh." Global Health: Science and Practice 3.3 (2015): 405-418.
Freedman, Stephen B., et al. "Diagnosing clinically significant dehydration in children with acute gastroenteritis using noninvasive methods: a meta-analysis." The Journal of pediatrics 166.4 (2015): 908-916.
Friedman, Jeremy N., et al. "Development of a clinical dehydration scale for use in children between 1 and 36 months of age." The Journal of pediatrics 145.2 (2004): 201-207.
Gorelick, Marc H., Kathy N. Shaw, and Kathleen O. Murphy. "Validity and reliability of clinical signs in the diagnosis of dehydration in children." Pediatrics 99.5 (1997): e6-e6.
Holliday, Malcolm A., and William E. Segar. "The maintenance need for water in parenteral fluid therapy." Pediatrics 19.5 (1957): 823-832.
Meyers, Rachel S. "Pediatric fluid and electrolyte therapy." The Journal of Pediatric Pharmacology and Therapeutics 14.4 (2009): 204-211.
Wang, Jingjing, Erdi Xu, and Yanfeng Xiao. "Isotonic versus hypotonic maintenance IV fluids in hospitalized children: a meta-analysis." Pediatrics (2013): peds-2013.
Neilson, Julie, et al. "Intravenous fluids in children and young people: summary of NICE guidance." BMJ: British Medical Journal (Online) 351 (2015).
Arikan, Ayse Akcan, and Agop Citak. "Pediatric shock." Signa Vitae 3.1 (2008): 13-23.