Management of Diabetes

Question 1

What are the effects of acute deficiency of insulin, as in untreated Type 1 DM?

Answer 1

1. Excessive urination – the bodies response to too much glucose in the blood. The body tries to remove it through urination
2. Excessive thirst – during excessive urination, the body is also removing water from the body so become thirsty.
3. Tiredness – as the body cannot access the glucose in the blood, it is missing its energy source hence the feeling of tiredness.
4. Thinner – When the body cannot access blood glucose via an insulin deficiency, it starts to break down muscle and fat to try and get the energy it requires.

Question 2

What is the distinction between Type I and Type II Diabetes, with reference to insulin
availability to and action upon its target cells?

Answer 2

1. Type I diabetes – The pancreas is unable to produce insulin from the beta cells in the pancreas. These cells are destroyed by an autoimmune disease
2. Type II diabetes – The pancreas produces enough insulin, but the insulin receptors on the target tissues are unable to uptake the glucose which is bound to insulin. Essentially the target tissues have become insensitive to insulin. Type II diabetics can also have problems producing enough insulin

Question 3

What are the effects of insulin in the control of blood glucose?

Answer 3

1. Insulin allows cells to uptake glucose that is circulating in the blood, this means that insulin helps to reduce blood glucose

Question 4

What are the sites of action of insulin?

Answer 4

1. Tyrosine kinase receptors on cell membrane of target tissues

Question 5

What are the mechanisms of action of insulin?

Answer 5

1) Once Insulin has been release by the Beta-cells of the Pancreas it attaches itself to the Tyrosine Kinase receptors of the insulin-sensitive tissues.
2) Once bound to the Tyrosine Kinase receptors, Insulin stimulates GLUT4 transporters to move to the cell membrane and take glucose into the cell

Question 6

What is the interaction of insulin with the counter regulatory hormone glucagon?

Answer 6

An increase in plasma insulin levels results in a decrease in plasma glucagon levels.

Question 7

What is the interaction of insulin with the counter regulatory hormone adrenaline?

Answer 7

An increase in plasma adrenaline levels would result in a reduced plasma insulin levels

Question 8

What is the interaction of insulin with the counter regulatory hormone cortisol?

Answer 8

An increase in plasma cortisol levels will result in a decrease in the effectiveness of insulin, i.e. cortisol produces insulin resistence

Question 9

What is the interaction of insulin with the counter regulatory hormone growth hormone?

Answer 9

An increase in GH levels results in a decrease in insulin effectiveness, and hence a decrease in glucose uptake by cells

Question 10

How can glucose metabolism change in times of stress (exercise, starvation, diabetes)?

Answer 10

Exercise - Glucose metabolism will be increased and there will e an increase in the number of GLUT-4 transporters at the cell membrane.

Starvation - Glucose metabolism will be decreased, as the body will switch to burning fat for its energy source.

Diabetes - The body is worse at anabolising glucose

Question 11

What is the aetiology and risk of DKA?

Answer 11

Aetiology:

1) Lack of access to nutrients in the blood (e.g. lack of insulin due to forgetting to take insulin injection)
2) Body breaks down reserves from fat and muscle as cannot get energy from glucose
3) Breakdown of fats and muscle results in elevated levels of FFA’s and ketones in the blood.
4) The lack of insulin in the diabetic patient means that the ketones cannot be taken up by the cells that require them.
5) Build up acidic ketones means the blood becomes acidic
6) Life-threatening acidosis = <7.1

Risk of DKA:

• Being a Type 1 Diabetic
• Having an infection
• Missing Insulin injections
• Steroid medication

Question 12

What are the causes, prophylaxis and treatment of hypoglycaemia (“hypos”) and
hyperglycaemia (diabetic ketoacidosis (DKA) and hyperosmolar hyperglycaemic state (HHS))?

Answer 12

1. Hypos:
   
   1. Causes – Injecting too much insulin, skipping meals, exercise, alcohol, injection site problems
   2. Prevention – Patients should carry CHO/orange juice with them, regularly monitor blood glucose levels, rotate injection sites, alter insulin before and after exercise
   3. Treatment – 15-20g CHO, fruit juice, glucgon
2. DKA:
   
   1. Causes – Drastic reduction in insulin – cells don’t have enough glucose so starts breaking down fats and proteins for energy – this results in elevated blood FAA concentrations creating acidosis.
   2. Prevention – Education
   3. Treatment – IV saline, IV insulin, IV potassium

Question 13

How is type I diabetes treated?

Answer 13

1. Insulin with varying lengths of action:
   
   1. Rapid acting – Humalog, Novorapid
   2. Short acting – Humulin S
   3. Intermediate acting – Isophane
   4. Long acting – Lantus