Hypoglycaemia

Question 1

What is hypoglycaemia?

Answer 1

A condition characterized by abnormally low blood glucose levels.

Question 2

What are some causes of hypoglycaemia?

Answer 2

1. Insulinoma - increased ratio of proinsulin to insulin
2. Self-administration of insulin/sulphonylureas
3. Liver failure
4. Addison’s disease
5. Alcohol - causes exaggerated insulin secretion due to its effect on pancreatic microcirculation.
6. Nesidioblastosis - beta cell hyperplasia.

Question 3

What is the physiological response to hypoglycaemia?

Answer 3

1. Hormonal response: decreased insulin secretion followed by increased glucagon secretion, with growth hormone and cortisol released later.
2. Sympathoadrenal response: increased catecholamine-mediated and acetylcholine-mediated neurotransmission.

Question 4

How are blood glucose levels and symptoms correlated in hypoglycaemia?

Answer 4

Blood glucose levels and the severity of symptoms are not always correlated, especially in patients with diabetes.

Question 5

What autonomic symptoms occur at blood glucose concentrations <3.3 mmol/L?

Answer 5

1. Sweating
2. Shaking
3. Hunger
4. Anxiety
5. Nausea

Question 6

What neuroglycopenic symptoms occur at blood glucose concentrations <2.8 mmol/L?

Answer 6

1. Weakness
2. Vision changes
3. Confusion
4. Dizziness

Question 7

What are severe and uncommon features of hypoglycaemia?

Answer 7

1. Convulsion
2. Coma

Question 8

How is hypoglycaemia investigated?

Answer 8

A combination of serum insulin and C-peptide levels can be measured to determine the cause.

Question 9

What does a high insulin and high C-peptide level indicate?

Answer 9

Endogenous insulin production, potentially due to insulinoma or sulfonylurea use/abuse.

Question 10

What does a high insulin and low C-peptide level indicate?

Answer 10

Exogenous insulin administration, such as exogenous insulin overdose or factitious disorder.

Question 11

What does a low insulin and low C-peptide level indicate?

Answer 11

Non-insulin-related causes, such as alcohol-induced hypoglycaemia, critical illness, adrenal insufficiency, growth hormone deficiency, or fasting/starvation.

Question 12

What is the initial management of hypoglycaemia in the community?

Answer 12

Oral glucose 10-20g should be given in liquid, gel, or tablet form, or a proprietary quick-acting carbohydrate like GlucoGel or Dextrogel.

Question 13

What is a ‘HypoKit’?

Answer 13

A kit that may be prescribed containing a syringe and vial of glucagon for IM or SC injection at home.

Question 14

What should be done for a conscious patient in a hospital setting with hypoglycaemia?

Answer 14

A quick-acting carbohydrate may be given.

Question 15

What should be done for an unconscious patient in a hospital setting with hypoglycaemia?

Answer 15

Subcutaneous or intramuscular injection of glucagon may be given, or intravenous 20% glucose solution may be administered.