Hypoglycaemia

Disclaimer

These guidelines have been produced to guide clinical decision making for the medical, nursing and allied health staff of Perth Children’s Hospital. They are not strict protocols, and they do not replace the judgement of a senior clinician. Clinical common-sense should be applied at all times. These clinical guidelines should never be relied on as a substitute for proper assessment with respect to the particular circumstances of each case and the needs of each patient. Clinicians should also consider the local skill level available and their local area policies before following any guideline. 

Read the full PCH Emergency Department disclaimer.

Aim 

To guide staff with the assessment and management of hypoglycaemia in the Emergency Department.

Key points

  • In non-diabetics hypoglycaemia is a low Blood Glucose Level (BGL) and can be defined as:
    • < 2.6 mmol/L in neonates
    • < 2.5mmol /L in children
  • Hypoglycaemia in children with diabetes is a low Blood Glucose Level (BGL) <4.0mmol/L in all diabetic children
  • Refer to Diabetes Hypoglycaemia Management for inpatient management.

Causes of hypoglycaemia

Increased glucose utilisation

  • Hyperinsulinism
  • Hypoglycaemic drug administration
  • Sepsis
  • Multiple trauma

Abnormalities in hormone secretion

  • Growth hormone deficiency
  • Adrenal insufficiency

Abnormalities in fuel substrate metabolism (defects in metabolism or utilisation)

  • Metabolic disorders - inborn errors of carbohydrate, amino acid or fatty acid metabolism (e.g. MCAD)
  • Acquired defects - liver disease, alcohol and salicylate ingestion

Abnormalities of substrate availability

  • Starvation
  • Ketotic hypoglycaemia

 

Assessment

  • Use of bedside glucometers are inaccurate in determining blood glucose levels below 4mmol/L
  • Laboratory (including satellite laboratory blood gas machine) estimation of glucose values are essential

Symptoms of hypoglycaemia

Autonomic Neurological
Pallor
Sweating
Tremor
Hunger
Weakness
Nausea
Anxiety
Abdominal pain

Confusion
Irritability
Drowsiness
Coma
Convulsions
Headache
Behaviour disturbance
Visual disturbance

Investigations

The following should be performed at the time when the child is hypoglycaemic and are the most useful investigations for unexplained hypoglycaemia.

Bedside Glucometer

Bedside Glucometers are inaccurate in determining blood glucose levels below 4mmol/L. Laboratory (including satellite laboratory blood gas machine) estimation of glucose values are essential.

Critical Sample

This is the most useful investigation of unexplained hypoglycaemia in childhood and should be performed at the time when the child is hypoglycaemic. The following samples should be taken:

Test CollectionTube / Container    Minimum Volume
Insulin, growth hormone, cortisol Clotted (analysed immediately)  Red top - black ring 1mL
Plasma glucose, ammonia, β-hydroxybutyrate, amino acids, acylcarnitines
Lithium heparin (on ice)
Green Top (4mL)  1.5 mL
Blood gas  Heparinised blood gas syringe    
Urine metabolic screen (taken as close to the event as possible)
Standard urine collection container
  5mL

Results during hypoglycaemia
  • Insulin levels should be undetectable (increased levels = hyperinsulinism)
  • Growth hormone and cortisol should be increased (no rise = deficiency)
  • Ketones should be present in urine (lack of ketones = hyperinsulinism or MCAD).

Management

Severe hypoglycaemia

  • 10% Dextrose 2mL/kg (= 0.2g/kg) given IV over 5-10 minutes
  • Continue IV 10% Dextrose infusion at maintenance rates until BGL is normalised (> 5mmol/L for 2 hours)
  • Repeat BGL at 30 minutes, then at hourly intervals
  • Be aware of recurrent hypoglycaemia, especially as a result of oral hypoglycaemic drug ingestion.

Note:

  • In some circumstances (e.g. hyperinsulinism) infusion concentrations greater than 10% Dextrose may be needed to maintain blood glucose level
  • Central venous lines are preferred for infusions of high Dextrose concentrations as extravasation is extremely irritant.

Bibliography

  1. AMH Children’s Dosing Companion (2015) Australian Medicines Handbook Pty Ltd
  2. Thornton PS, Stanley CA, De Leon DD, Harris D, Haymond MW, Hussain K, Levitsky LL, Murad MH, Rozance PJ, Simmons RA, Sperling MA, Weinstein DA, White NH, Wolfsdorf JI J. Recommendations from the Pediatric Endocrine Society for Evaluation and Management of Persistent Hypoglycemia in Neonates, Infants, and Children. Pediatr. 2015;167(2):238. 
  3. Haymond M W. Hypoglycemia in infants and children. Endocrinol Metab Clin North Am. 1989;18(1):211.


Endorsed by:  Director, Emergency Department   Date:  Mar 2018


 Review date:   Mar 2021


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