Management of hyperosmolar hyperglycaemic state in adults with diabetes.

Hyperglycaemic hyperosmolar state (HHS) is a medical emergency, which differs from diabetic ketoacidosis (DKA) and requires a different approach. The present article summarizes the recent guidance on HHS that has been produced by the Joint British Diabetes Societies for Inpatient Care, available in full at http://www.diabetologists-abcd.org.uk/JBDS/JBDS_IP_HHS_Adults.pdf. HHS has a higher mortality rate than DKA and may be complicated by myocardial infarction, stroke, seizures, cerebral oedema and central pontine myelinolysis and there is some evidence that rapid changes in osmolality during treatment may be the precipitant of central pontine myelinolysis. Whilst DKA presents within hours of onset, HHS comes on over many days, and the dehydration and metabolic disturbances are more extreme. The key points in these HHS guidelines include: (1) monitoring of the response to treatment: (i) measure or calculate the serum osmolality regularly to monitor the response to treatment and (ii) aim to reduce osmolality by 3-8 mOsm/kg/h; (2) fluid and insulin administration: (i) use i.v. 0.9% sodium chloride solution as the principal fluid to restore circulating volume and reverse dehydration, (ii) fluid replacement alone will cause a fall in blood glucose (BG) level, (iii) withhold insulin until the BG level is no longer falling with i.v. fluids alone (unless ketonaemic), (iv) an initial rise in sodium level is expected and is not itself an indication for hypotonic fluids and (v) early use of insulin (before fluids) may be detrimental; and (3) delivery of care: (i) The diabetes specialist team should be involved as soon as possible and (ii) patients should be nursed in areas where staff are experienced in the management of HHS.