Hyperosmolar hyperglycaemic state

Question 1

What is hyperosmolar hyperglycaemic state?

Answer 1

A medical emergency where hyperglycaemia has resulted in osmotic diuresis (increased peeing) - leading to severe dehydration and electrolyte deficiencies.

Question 2

What electrolyte disturbances are usually seen in hyperosmolar hyperglycaemic state?

Answer 2

Hypotonia.
Hypokalaemia.

Both sodium and potassium are excreted alongside glucose in the urine.

Question 3

How does the body become hyperosmolar?

Answer 3

The loss of fluid in the serum leads to an increased osmolarity.

The blood becomes hyper viscous.

Question 4

what is the typical hyperosmolar value seen in HHS?

Answer 4

> 320mosmol/kg.

Question 5

why might patients not look dehydrated even though they are extremely so?

Answer 5

The body becomes hypertonic (muscle tone increases) leading to the muscles looking preserved.

Question 6

What are the signs of HHS?

Answer 6

Fatigue
Lethargy
Nausea
Vomiting
Altered consciousness
Headaches
Papilloedema
Weakness
Hyperviscosity
Dehydration
Hypotenson
Tachycardia

Question 7

what complications can arise due to hyper viscosity?

Answer 7

Myocardial infarctions
Stroke
Peripheral arterial thrombosis

Question 8

How long does HHS take to present?

Answer 8

It takes days (slower onset than DKA) which is why the results are usually more severe.

Question 9

How high is blood glucose levels usually in HHS?

Answer 9

Usually >30mmol/L.

WITHOUT KETONAEMIA OR ACIDOSIS.

Question 10

what are the main differences between HHS and DKA?

Answer 10

• HHS has hyperglycaemia but NOT ketonuria or acidosis.
• DKA has hyperglycaemia, ketonuria and acidosis.
• HHS arises over days, DKA arises over hours.
• HHS has a higher mortality than DKA.
• HHS is more common in T2D, DKA is more common in T1D.
• The internal insulin in T2D means ketones are not produced in HHS.
• Hypotension and hyperosmolarity are present in HHS, usually in DKA they are not.

Question 11

Why does HHS not cause acidosis and ketonuria?

Answer 11

It usually occurs in T2D patients, who still create insulin.

This insulin is not enough to control blood glucose levels (hence hyperglycaemia and hyperosmolarity) BUT it is enough to prevent ketogenesis.

Question 12

What is the treatment priorities for HHS?

Answer 12

Rehydration and electrolyte disturbances should be treated before hyperglycaemia.

Question 13

What are the main things to remember when treating HHS?

Answer 13

• Rehydration + electrolyte fixing > lowering blood glucose.
• Rehydration should be done more slowly than in DKA.
• VTE prophylaxis should be given due to hyperviscous state.

Question 13

What are the main things to remember when treating HHS?

Answer 13

• Rehydration + electrolyte fixing > lowering blood glucose.
• Rehydration should be done more slowly than in DKA.
• VTE prophylaxis should be given due to hyperviscous state.

Question 14

What fluid is given to treat HHS?

Answer 14

0. 9% saline.
   - can add KCL to this.
   - Change to 0.45% saline if failing to reduce osmolality.

Question 15

When should insulin be given in HHS?

Answer 15

ONLY if ketones >1mmol/L OR if glucose fails to fall with fluid replacement.
Or if severe acidosis.

Question 16

Why is 0.9% saline used?

Answer 16

Because it is hypotonic so helps to lower serum osmolality.

Question 17

What is the goal regarding timings for fluid replacement?

Answer 17

50% of fluid lost should be replaced in the first 12 hours.

The net 50% should be replaced in the next 12 hours.

Question 18

Why should insulin never be given before fluid replacement?

Answer 18

The water might move out of the intravascular space and cause cardiovascular collapse.