You’ve found a patient is hyperglycaemic & either they are ketotic or have significant hyperglycaemia (>30mmol/L) and so you suspect DKA or HHS respectively.

These conditions carry a high mortality and therefore you must escalate all cases to your seniors.

Diabetic Ketoacidosis (DKA)
DKA is defined as the biochemical triad of:

  • Ketonaemia ≥3 mmol/L (on ketone meter) OR significant ketonuria (≥2+ on standard urine sticks)
  • Blood glucose ≥ 11mmol/L OR known diabetes mellitus*
  • Bicarbonate (HCO3) below 15mmol/L AND/OR venous pH < 7.3

*Some patients may be euglycaemic or mildly hyperglycaemic (particularly those on SGLT2 inhibitors). It is important to always test for ketones.

Clinical features
DKA usually evolves rapidly over 24 hours, with presenting symptoms secondary to severe metabolic acidosis:

  • Abdominal pain
  • Nausea and vomiting
  • Hyperventilation (Kussmaul’s breathing)
  • Fruity odour
  • Signs of volume depletion

Severe DKA

Indications of severe DKA requiring consideration of HDU involvement:
  • Blood ketones > 6mmol/L
  • Bicarbonate < 5mmol/L
  • Venous/arterial pH < 7.0
  • Hypo or hyperkalaemia on admission (ensure cardiac monitoring & beware that insulin & fluids will cause the potassium to fall further)
  • GCS < 12 or abnormal AVPU scale (consider a nasogastric tube to reduce the risk of aspiration)
  • SpO2 <92% on air (assuming normal baseline respiratory function)
  • SBP <90mmHg OR HR >100 or <60 bpm

For the following, I’ve used the Diabetes UK guidelines

Immediate Management (in the first hour)

  • ABCDE management
  • Fluid boluses as required if shocked/hypotensive. If unresponsive to fluids consider alternative causes of hypotension/shock
  • Investigations include: FBC, U&E, VBG, blood cultures, ECG, CXR, Urine MC&S (& pregnancy test)
  • Start fluids & insulin as per your local guidelines. This might be:
    • 1L 0.9% sodium chloride over 1 hour
    • Fixed-rate insulin infusion at 0.1 units/kg/hour – for 70kg man this would be 7 units per hour (usually made of 50 units of Actrapid in 50ml of 0.9% sodium chloride)
  • Consider the underlying trigger & treat this – diarrhoea/vomiting, sepsis, ACS

Be careful of fluids in the elderly, pregnant, heart/kidney failure or 18-25 years of age – senior involvement is necessary to avoid fluid overload or cerebral oedema.

The fluid deficit is about 1L per 10kg (i.e. 7L in a 70kg patient)

After the first hour (to 6 hours)
The focus is on hydrating the patient & replacing the potassium to ensure it remains in the normal range whilst the acidosis & ketonaemia improves. Don’t forget to:
  • Prescribe their long acting insulin as this prevents rebound hyperglycaemia on discontinuation of the insulin infusion (local guidelines in some places may recommend against this)
  • Don’t forget VTE prophylaxis (they’re at a high risk of clots).
  • Measure hourly – levels should fall at 0.5mmol/L/hour. If not available use measure bicarbonate using VBGs – levels should increase at 3mmol/L/hour.
  • If not falling, check the syringe pump is working & escalate to seniors (for consideration of a higher rate of insulin infusion)
  • Take a VBG at 1 hour and then 2-4 hourly thereafter (at least with every new bag of IV fluids to determine the amount of potassium in each one)
  • Ensure the potassium remains in the normal range (maximum rate ≤ 10mmol/hour via a peripheral line)
    • This means the 2 hourly bags would have a maximum of 20mmol/L
  • Diabetes UK recommends:
    • Over 5.5mmol/L – none
    • Between 3.5-5.5, 40mmol/L of potassium
    • Below 3.5mmol/L – senior involvement
  • Ensure the patient is passing urine (otherwise the potassium might rise). Catheterise if necessary to monitor urine output.
Screenshot%2B2020 06 04%2Bat%2B16.53.24
Diabetes UK
  • Measure hourly, aiming to avoid hypoglycaemia
  • If the glucose falls below 14mmol/L, commence glucose 10% at 125ml/hour (1L over 8 hours) alongside 0.9% sodium chloride.
After 6 hours

  • Continue fluids & insulin (monitor for complications of pulmonary oedema & cerebral oedema)
  • Insulin should not be stopped until the ketosis resolves

After 12 hours

  • Look for resolution of DKA
    • Ketones <0.6mmol/L or Urine: 1+ or negative
    • Venous pH >7.3
  • If DKA has resolved
    • If eating & drinking, ideally switch at mealtime. Start their normal insulin regime, stopping the insulin infusion 1 hour after administering their subcutaneous short-acting dose
    • If not eating & drinking, switch to a variable rate insulin infusion until you can do the above
  • If after 24 hours, DKA has not resolved – specialist input is required as this is unusual
  • Conversion to insulin for the insulin-naive should be done by a specialist team

Hyperosmolar Hyperglycaemic State (HHS, previously known as HONK)

Although often discussed separately, HHS and DKA exist on a spectrum with frequent overlap. Mortality is around 10-20% (higher than DKA) and therefore this should be managed by your seniors. All but mild cases usually require ITU input.

There is no strict definition, however characteristic features include:

  • Severe hyperglycaemia (≥30mmol/L)
  • Absence of significant ketoacidosis (ketones <3.0mmol/L, pH >7.3, bicarbonate >15)
  • Hyperosmolality (Serum osmolality ≥320mosmol/kg [2xNa+ + Glucose + Urea])
  • Hypovolaemia

Clinical features
Insidious onset over days with weight loss, polyuria and polydipsia, leading to more extreme dehydration and metabolic disturbances.

Aetiology frequently includes infection/sepsis or macrovascular events (ACS/stroke) or other illnesses that impair access to water intake.

Can present neurological symptoms due to hyperosmolality:

  • Focal neurological signs
  • Seizures
  • Decreased GCS
Severe HHS or patients requiring ITU input (any of the following criteria)
  • Osmolality >350mosmol/kg
  • Sodium >160 mmol/L, hypo or hyperkalaemic
  • pH <7.1
  • GCS < 12 or abnormal AVPU scale (consider a nasogastric tube to reduce the risk of aspiration)
  • SpO2 <92% on air (assuming normal baseline respiratory function)
  • SBP <90mmHg OR HR >100 or <60 bpm
  • Urine output less than 0.5ml/kg/h or Creatinine above 200
  • Hypothermia
  • Macrovascular event or serious co-morbidity

Management (based on Diabetes UK guidelines)

  • ABCDE management. Fluid boluses as required for shocked/hypotensive patients
  • Investigations include: FBC, U&E, LFTs, bone profile, magnesium, VBG, blood cultures, ECG, CXR, Urine MC&S & sputum MC&S. Have a low threshold for a Troponin.
  • Fluids are continued with hourly monitoring of blood glucose
  • Local guidelines may vary from those who start insulin immediately to those only after glucose ceases to fall with fluids alone.
  • Usually, a fixed-rate insulin infusion scale is used at 0.05 units/kg/hour which is titrated to aim for a glucose or osmolility reduction of about 3mmol/L/hour
  • Usually, electrolytes and renal function are checked every 2-4 hours
  • Ensure potassium replacement & VTE prophylaxis

Further Reading & References

Written by Dr Helena Fawdry (FY1) & Dr Akash Doshi (CT2)

How useful was this post?

Click on a star to rate it!

Average rating 4.9 / 5. Vote count: 22

No votes so far! Be the first to rate this post.

As you found this post useful...

Follow us on social media!

We are sorry that this post was not useful for you!

Let us improve this post!

Tell us how we can improve this post?

Related Posts

Gastroenterology in Primary Care
Gastroenterology in Primary Care
INTRODUCTION This article covers common gastroenterological...
Medication in Diabetes
Medications in Diabetes
In this article, we’ll cover the treatments used in Diabetes...
Red Eye
Red Eye
Red eye is one of the most common eye presentations you will...

Leave a Comment

Your email address will not be published. Required fields are marked *

Follow us



Trending Now

Doctor's Pay Calculator 2024
We’ve created a pay calculator to help you better understand your salary, how much tax you’ll...
Paracetamol Overdose
Paracetamol overdose is a common presentation in A&E and so you may often find yourself looking after...
Understanding the MSRA
The Multiple Specialty Recruitment Assessment (MSRA) is a computer-based exam increasingly being used...
How to take a psychiatric history
Psychiatry, as a specialty is unique in that diagnostic methods, rely very heavily on symptomatology,...
Common Viral Infections (exanthem) in Paediatrics
Viral infections are extremely common in paediatrics and a common presentation to paediatric A&E...
Abdominal X-rays
The advantages of AXRs are far less radiation to patients & that they’re logistically easy...
Essential Apps
Here’s a list of apps that are in order of how essential we find them. There’s probably more...

Sign up for our awesome resources

Join over 40,000 users who have signed up for our free weekly webinars, referral cheat sheet & other exclusive content!