A two-week-old baby is brought to your general ICU in extremis pending transfer to a Paediatric centre. Born at term, she had been discharged well on day 5 of life. For three days she has had progressive tachypnoea, lethargy and failure to feed, and has now presented after a seizure. She has been intubated in the Emergency Department.
Blood test results taken on air prior to intubation are shown below:
Parameter |
Patient Value |
Adult Normal Range |
OH |
7.04* |
7.35 - 7.45 |
PCO2 |
14 mmHg 1.9 kPa)* |
35 —45 (4.6 — 6.0) |
P02 |
80 mmHa (10.5 kPa) |
|
Bicarbonate |
5 mmol/L* |
22 - 28 |
Lactate |
8 mmol/L* |
|
Glucose |
0.9 mmol/L* |
3.5 - 6.1 |
White Cell Count |
14.7 x 109/L* |
4.0 - 1 1.0 |
Neutrophils |
27% |
|
Lymphocytes |
70% |
|
Alanine aminotransferase (ALT) |
1600 U/L* |
10-55 |
Aspartate aminotransferase (AST) |
2200 U/L* |
10 —40 |
a) List, in broad terms, the key differential diagnoses for this presentation (20% marks)
b) Outline your approach to differentiating between these diagnoses. (30% marks)
c) Outline principles of early management pending transfer. (50% marks)
a)
Inborn error of metabolism
Sepsis (viral likely)
Cardiac disease- especially duct dependent disease
Trauma (NAI)
Drugs / Toxins
b)
History:
Exposure to ill persons including siblings and parents.
“Colds”, chicken pox and maternal herpes should be specifically solicited.
Maternal Group B Strep swab should be reviewed
Injury
Cyanotic spells Apnoeas
Family history including infant deaths, inborn errors of metabolism (IEMs), cardiac disease, degree of consanguinity
Examination:
General exam - trauma, rash Liver edge (failure, hepatitis) Murmurs Femoral pulses
Investigations:
CXR
ECG
Ammonia
Urine amino and organic acids (if can’t be processed, take while acidotic and store) Cultures if not done
CMV, HSV PCR
Consider skeletal survey if any suggestion of injury
Cranial ultrasound (widely available)
Echo if available
c) Ongoing liaison with receiving centre.
Restore then maintain BSL using 10% Glucose (2.5-5ml/kg 10% glucose bolus then 6mg/kg/min infusion.)
Restore intravascular volume (even post FEAST fluid bolus reasonable)
Direct therapy if specific pathology found- e.g. alprostadil infusion if evidence of duct dependent cardiac disease
Empiric antibiotics
Empiric antiviral given results above (acyclovir or ganciclovir)
Nil protein intake till initial metabolic results in- maintain on glucose as above
Lung protective ventilation
General ICU housekeeping.
Examiners Comments:
Reasonably well done. Part a) was answered better than b) and c). Some candidates did not read the question completely and described intubation of the baby.
This question, and the college answer, are weirdly identical to Question 10 from the first paper of 2015, except now they have capitalised the word "Paediatric", and in 2018 the bloods merely "show," instead of now being "shown below". What was the merit of making these changes without altering any other features of the question? What is the significance of these changes? Surely there must be some reason behind them, because it would have required less effort to simply cut and paste the SAQ. However, this line of thinking is unproductive. Trying to get into the examiner's heads in the pursuit of some hidden eldritch meaning, there is some risk that a trainee might suddenly be confronted with the Lovecraftian cosmic horror of realising that nobody is carefully tending to the wording or syntax of these SAQs. Gibbering madness may ensue.
In context of these matters, below one may see that the author has cut-and-pasted the entire discussion section from Question 10 from the first paper of 2015, with subtle changes which on the surface might appear random and cosmetic.
a) Differentials for this shock-like presentation:
Domain | Neonate/infant age group | Children older than 12 months |
Vascular |
|
|
Infectious |
|
|
Neoplastic |
|
|
Drug-induced |
|
|
Congenital |
|
|
Autoimmune |
|
|
Trauma |
|
|
Endocrine or metabolic |
|
|
b) Assessment of this shock state:
Generic to the infant/paediatric population | ||
History
|
Examination
|
Investigations
|
Specific for the neonatal population: | ||
|
|
|
c) Approach to management, which is very generic:
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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.
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