Hyperglycaemic Hyperosmolar State (HHS)

Warning

Diagnosis

  • hypovolaemia
  • osmolality usually greater than 320 mOsm/kg
  • marked hyperglycaemia (usually greater than 30 mmol/L)

If significant ketosis (capillary greater than 3 mmol/L, urine greater than 2+) or acidosis (H+ more than 45 mmol/L; HCO3- less than 15 mmol/L) present treat as per the diabetic ketoacidosis (DKA) protocol.

Initial assessment

An initial assessment form and monitoring chart (admission to 24 hours) is available to record required information. 

Key aspects to good care

  • repeated clinical and biochemical assessment is essential
  • the patient’s ability to tolerate shifts in fluid balance if co-existing cardiac or renal disease must be taken into consideration
  • assess if any markers of severity present (see section 'markers of severity')
  • inform the on-call diabetes team.The BGH diabetes team are available in working hours. Contact diabetes/endocrinology via diabetes liaison nurse email inbox or, if urgent review required, via bleep to consultant covering ward referrals - diabetes secretaries have this rota.

Key treatment goals

  • osmolality reducing by 3-8 mOsm/kg per hour
  • plasma glucose reducing by 1-5 mmol/L per hour aiming for a target range of 10-15 mmol/L
  • fluid replacement aims:
    • achieve positive fluid balance of 2-3L by 6 hours
    • achieve positive fluid balance of 50% of the estimated fluid loss within 12-24 hours and 100% estimated fluid loss by 24-48 hrs
    • always adapt fluid replacement to clinical assessment and presence of co-morbidities

Hour 1: assessment and treatment

Assessment:

  • perform clinical assessment and necessary investigations as determined by the clinical picture eg ECG/sepsis screen/foot examination
  • measure capillary glucose, capillary or urinary ketones, U&Es, venous blood gas, lactate, calculated osmolality
  • consider catheterisation to allow accurate fluid balance measurement

Treatment:

  • commence IV 0.9% sodium chloride – 1L over 1 hour
  • commence insulin (Actrapid 0.05 units/kg/hour intravenously) only if significant ketonaemia (plasma ketones more than 1 mmol/L or urinary ketones more than 2+)
  • commence prophylactic LMWH unless contraindicated (patients are at high risk of thromboembolic disease)
  • treat any identified precipitant – eg infection, stroke, acute coronary syndrome

Hours 1-6 of treatment

Aim for a gradual decline in osmolality (3-8 mOsmol/kg/hour) and achieve positive fluid balance 2-3L by 6 hours.

  • measure glucose, U&Es and calculate osmolality as per timings on flow sheet (page 3)
  • monitor urine output
  • adjust fluid administration based on clinical assessment and measurement of osmolality
  • potassium replacement (see section 'potassium replacement')

If by 6 hours:

  • osmolality falling less than desired rate (3-8 mOsmol/kg/hour)
    • if dehydrated clinically increase the IV fluid rate per hour
    • if patient in positive balance of more than 3L, commence IV insulin (Actrapid) at 0.05 units/kg/hour
  • glucose falling less than desired rate (1-5 mmol/litre per hours) - commence insulin (Actrapid) - aim to keep glucose between 10-15 mmol/L
  • Glucose falls below 14 mmol/L - commence 10% dextrose at 125ml/hr in addition to current fluids (ensure that this additional fluid is taken into consideration for other infusion rates)

Aim to achieve positive fluid balance of 50% estimated fluid loss within 12-24 hours and 100% estimated fluid loss by 24-48 hrs.

Continuing care

  • consider and treat precipitating cause e.g. sepsis, stroke, myocardial infarction, limb ischaemia
  • monitor for cerebral oedema
  • assess for arterial venous thrombosis/pressure ulcers/ foot ulceration
  • continue regular biochemical and clinical evaluation of hydration status

Markers of severity

If 2 or more present discuss with senior medical staff and if appropriate consider discussion with critical care:

  • osmolality more than 350 mOsmol/kg
  • H+ more than 80mmol/L
  • GCS less than 12
  • systolic BP less than 90 mmHg
  • urine output less than 0.5 ml/kg/hr
  • hypothermia
  • sodium more than 160 mmol/L
  • potassium less than 3.5 mmol/L or 6.0mmol/L
  • oxygen saturations less than 92% (if normal at baseline)
  • creatinine more than 200 micromol/L
  • macrovascular or other serious co-morbidity

Potassium replacement

  • If K+ above 5.5 mmol/L - no additional KCL
  • If K+ between 3.5 and 5.5 mmol/L – prescribe 40 mmol KCL per litre of infusion fluid
  • If K+ below 3.5 mmol/L - seek senior advice as additional potassium is required

Ensure that the hourly rate of potassium administration is considered with rapid infusion rates.

Editorial Information

Last reviewed: 01/03/2022

Next review date: 01/03/2025

Author(s): Williamson R.

Version: 3

Author email(s): rachel.williamson@borders.scot.nhs.uk.

Related guidelines