The Unconscious Baby Flashcards
What can cause a raised RR in a neonate with altered consciousness?
Sepsis - common even without a temperature Cardiac cause Respiratory disease Metabolic - acidosis, or raised ammonia Pain
What needs to needs to be considered in a child with altered consciousness?`
Sepsis
Meningitis - can cause altered consciousness and can accompany sepsis
Inborn metablic error (metabolic acidosis and raised ammonia can be seen in severe sepsis)
NAI
How do you calculate the anion gap?
(Na + K) - (Cl+Bic)
Normal anion gap is below 11
What are the 2 main groups of inborn errors of metabolism causing hyperammonaemia?
Urea cycle disorders
- Typically the ammonia level is markedly raised, often over 1000 micromols/L
- Liver dysfunction
- Blood gas often shows a respiratory alkalosis due to the ammonia acting as a respiratory stimulant
Organic acidaemia
- Mixed picture of metabolic acidosis and hyperammonaemia
- Hyperammonaemia is typically less than that seen in urea cycle defects
- 1st sign - Metabolic acidosis that does not respond to standard fluid resuscitation
2nd sign - Raised anion gap caused by the presence of the abnormal organic acid
Methylmalonic acidaemia and propionic acidaemia are the 2 most common organic acid disorders
Which inborn errors of metabolism are screened for at birth?
Phenyketonuria (PKU)
MCAD deficiency
What is PKU?
Mutation of Phenylalanine hydroxylase (PAH)
Body fails to convert phenylalanine to tyrosine
Accumulation of phenylalanine leads to severe developmental delay and seizures
What is the management of phenylalanine?
Very low protein diet
Supplements of all amino acids except phe
Monitoring of phe levels
What is Zellweger syndrome?
Disorder of embryogenesis
Absence of peroxisomes
High forehead, large anterior fontanelle
Shallow supraorbital ridges
Small lower jaw
High palate (sometimes cleft)
Brain kidney and bone abnormalities
Floppy
Rarely feed
Seizures
What is Hurler disease?
Disorder of remoddelling
Absense of lysosomal enzyme
Mucopolysaccharidosis
Coarse features - hair, thickening of subcut tissues Protrusion of tongue Sagging of cheeks Middle ear problems Large liver spleen Skeletal abnormalities Learning difficulties
Where does ammonia come from?
Breakdown of amino acids
Why does a newborn with a urea cycle disorder not immediately suffer from high levels of ammonia?
In the womb, ammonia would be excreted via the placenta
Ammonia gradually increases during the fisrt hours of birth
What are ammonia scavenger drugs?
Benzoate
Phenylacetate/Phenylbutyrate
Modulate hepatic nitrogen metabolism mainly by providing alternative pathways for nitrogen disposal
What conditions does the heel prick test for? (9)
Sickle Cell CF Hypothyroidism PKU Medium chin acyl co A dehydrogenase (MCAD) Mple syrup urine disease (MSUD) Homocystinuria Isovaleric acidaemia Glutaric aciduria
