Hyperosmolar Non-Ketotic Coma (HONC)
Hyperglycaemic Hyperosmolar state
Diagnostic criteria
- Hyperglycaemia ( glucose > 30 mmol/l)
- Total osmolality > 340mOsm/kg
- Serum bicarbonate >15mmol/l
- Urinary ketones < 1+ plus
Features
- Elderly
- Type 2 diabetes mellitus
- Marked hyperglycaemia
- Marked dehydration (over days)
- Altered level conc. correlates with serum osmolality
- No significant ketosis and acidosis
- Exacerbated by glucose drinks / diuretics
- Teat with GRADUAL normalisation biochemistry
- Beware co-existing medical conditions / triggers
- Beware thromboembolism.
Management
Osmolality
[2 x (Na+ + K+) + Urea + Glu]
Usually > 350 mosmmol/kg
- Oxygen.
- CVP monitoring often required to guide fluid replacement.
- NG tube if ↓ level of consciousness.
- Urinary catheter.
- Prophylactic heparin (Innohep), if no contraindications.
