see also:

• endocrinology
• diabetes mellitus
• insulin
• DDx of hyperglycaemia
• oral hypoglycaemic agents
• metformin
• hypoglycaemia
• diabetic ketoacidosis
• diabetes mellitus in children

• diabetes mellitus is an important co-morbidity factor for patients presenting to the ED, particularly, if they are type 1 insulin dependent diabetics as these patients often have their basal insulin requirements forgotten raising the risk of diabetic ketoacidosis
• if it is a first presentation, see Mx of 1st presentation diabetes mellitus instead

• check BSL on arrival (and preferably ketones)
  • given that DKA may also occur in T2DM patients with BSLs < 15 when they are on SGLT2 inhibitor induced diabetic ketoacidosis (gliflozin DKA) and many patients cannot recall exactly which medications they are on, as well as the possibility of undiagnosed Latent Auto-immune Diabetes of Adults LADA, or elderly patients actually being type 1 diabetics instead of the presumed type 2 diabetics, it is perhaps prudent to do a ketone level as well as BSL on arrival to ED for all diabetic patients
• if BSL is low
  • manage as per hypoglycaemia
• if ketones > 1mmol/L:
  • check venous blood gas to ascertain if there is acidosis present and thus potentially diabetic ketoacidosis (DKA)
    • whilst the usual cutoff for doing VBG is ketones > 1.7mmol/L, ED patients tend to be unwell and thus the lower cutoff of > 1mmol/L is in accordance with 2020 Australian Diabetic Society guidelines¹⁾
  • if venous pH < 7.30, contact Endocrinology Registrar for advice
  • serum ketones > 3.0mmol/L or bicarb < 15 or base excess < -5mmol/L or pH < 7.3 should raise suspicion of DKA!
• if ketones > 0.6 mmol/L but < 1.0 mmol/L:
  • re-check capillary ketones 6 hourly (or more often if the patient's general condition is worsening)
• if BSL is high and ketones are < 1mmol/L:
  • if type 2 diabetic, could they have hyperosmolar hyperglycaemic state (HSS or HONK)?
    • consider adding serum osmolality to list of bloods
• if none of the above are present:
  • ensure their basal insulin requirements are maintained to prevent diabetic ketoacidosis (DKA)
  • see below for additional considerations

• acute coronary syndromes which may be silent (ie. pain free or atypical such as presenting as epigastric pain)
• sepsis / septicaemia which may be afebrile or hypothermic (cold sepsis))
• increased risk of more rapid progression of surgical conditions such as diverticulitis
• stroke (CVA) - have a lower threshold for Ix with CT brain etc especially for vertigo - peripheral vs central, etc
• neuropathies and hence may present with atypical or occult presentations eg. foot fractures, burns, injuries, infections requiring vigilance and careful examination
• hypoglycaemia

• corticosteroids
• etc.

• multiple forms available
• widely differing doses
• risk of hypoglycaemia if excessive dosing or fasting
• risk of diabetic ketoacidosis (DKA) if basal dosing not given
• patients often do not recall which type of insulin or what dose they are on
• complexity of electronic ordering of prn sliding scale insulins

• see local guidelines