Non-clinical sciences/Lab medicine · Glucose emergencies

DKA vs HHS

What it means

DKA (T1DM): glucose >11 (or known DM) + ketones >3 + pH 30, osmolality >320, no significant ketones/acidosis; slower onset, profound dehydration; rehydrate first, cautious insulin only if glucose not falling.

Worked example

Glucose 35, osmolality 330, minimal ketones, no acidosis in an elderly T2DM patient → HHS (fluids first).

In the exam

An elderly type-2 diabetic is profoundly dehydrated with glucose 38, osmolality 335 but only trace ketones and a normal pH.

What settles it

DKA = ketones + acidosis (T1DM); HHS = extreme hyperglycaemia + hyperosmolality WITHOUT significant ketosis/acidosis (T2DM).

Classically confused with

Metabolic acidosis (raised anion gap)

Source: JBDS guidelines