Hypoglycaemia

Question 1

What is the threshold for plasma glucose to be classified as hypoglycaemia?

Answer 1

Below 4 mmol/L

Question 2

What are the most common cause of hypoglycaemia in diabetic patients? Name at least 3

Answer 2

• Dose error
• absorption problems, injection site problems
• missed or delayed meals.
• renal disease
• increased exercise
• drugs and hypoglycemic agents
• alcohol
• endocrine problems

Question 3

Name the clinical features of hypoglycaemia.

Answer 3

2 types of symptoms: Autonomic and neuroglycopenic.

Autonomic - sweating, feeling hot, palpitations, shaking, parasthesia
Neuroglycopenic - poor coordination/concentration, drowsiness, fits and coma.
Other - hunger, nausea, fatigue

Question 4

What are the investigations if you suspect hypoglycaemia.

Answer 4

Hypoglycemia - medical emergency esp if patint in coma or fit, measure

• capillary glucose reading
• FBC or CRP if underlying infection or sepsis
• renal function if renal impairement

If new/recurrent hypoglycemia and weight loss, investigate for Coeliac disease, hypoadrenalism and malignancy.

Question 5

What is the management of hypoglycaemia in adults who are conscious, oriented and able to swallow?

Answer 5

Emergency

Quick acting carbohydrate to return blood glucose to normal eg 150-200ml pure fruit juice, 90-120ml Lucozade or 4-5 Glucotabs

Repeat blood capillary glucose after 10 to 15 minutes

• if still < 4 mmo/L a further short acting carbohydrates should be given
• if > 4 mmol/L and the patient has recovered - long acting carbohydrate given e.g. two biscuits, a slice of toast or 300 mL glass of milk

In hospitals - hypo box on wards

Question 6

What do you need to do if the blood glucose fails to rise above 4 mmol/L after three cycles of short acting carbohydrates or after 45 minutes, or straight away if patient is unconscious or having a seizure?

Answer 6

Administer 1 mg of intramuscular glucagon

In hospital - 10% dextrose IV 100ml/hour

Question 7

What do you need to do once the acute hypoglycaemic episode has been treated?

Answer 7

• Find out the underlying cause
• educate the patient to prevent further episodes by involving the diabetic team
• encourage the patient to monitor blood glucose levels regularly and note patterns of recurrent hypoglycaemia to adjust insulin doses or diet
• educate patient about exercise and driving
• consider dose reduction of insulin depending on the underlying cause.

Question 8

What is impaired awareness of hypoglycaemia (IAH)?

Answer 8

Because the counterregulatory hormones and sympathetic neural response is impaired in diabetes some of the autonomic symptoms and signs are absent/occur at much lower level of plasma glucose so that the patient is unaware of hypoglycaemia

Question 9

What are the symptoms of fasting hypoglycemia?

Answer 9

Several hours after food (on waking, or at night) and can be precipitated by exercisse

• irritability, confusion, seizures, coma
• sweating
• pallor
• tachycardia

Question 10

What are some of the causes of fasting hypoglycemia?

Answer 10

Drugs eg insulin, alcohol
Organ failure eg liver/renal failure
Hormone deficiency eg Addison's disease
Insulinoma
Inborn errors of metabolism eg glycogen storage disease

Question 11

What are the causes of posprandial hyperglycemia?

Answer 11

Symptoms 2-5 hours after food

Post-gastrectomy
Alcohol induced
Incipient diabetes mellitus.

Question 12

How do you assess someone with hypoglycemia?

Answer 12

Clarify adrenergic (pallor, sweating, tachycardia, tremor) and neuroglycopenic (impaired concentration, irritability, confusion, seizures, coma)&raquo_space;> in FASTING or POSTPRANDIAL state?

PMH - drugs, diabetes, renal, liver, endocrine disease

Measure lab plasma glucose level (<2.5mmol/L) - pinprick unreliable
at low conc

Check liver and renal function

Septic screen.

Synacthen test - exclude adrenal insufficiency.

Question 13

How do you further investigate fasting hypoglycemia?

Answer 13

Fasting insulin
C peptide
Ketones
Glucose

measured during confirmed episode

Elevated insulin with hypoglycemia suggests insulinoma or exogenous insulin or sulphonylurea therapy - C peptide and ketones supressed in patients on exogenous insulin but elevated in insulionma or sulphonylureatherapy.

Question 14

How do you further investigate postprandial hypoglycemia?

Answer 14

75g OGTT with freq measurement of glucose for up to 6 hours - confirms postprandial hypoglycemia.

Question 15

How do you treat hypoglycemia, both fasting and postprandial?

Answer 15

Underlying cause eg insulinomas - surgery

Postprandial - low CHO diet and/or small meals

Question 16

What is the management of hypoglycaemia in adults who are Conscious but confused, disoriented, unable to cooperate or agressive but are able to swallow?

Answer 16

Give GlucoGel squeezed into mouth between teeth and gums

Or give glucagon 1mg IM