Treatment of T1DM

Question 1

Outline the normal glucose/insulin physiology

Answer 1

• Insulin is secreted at a low basal rate which accounts for 50% of insulin produced
• Post-prandial insulin is secreted in relation to post-meal glucose

(treatments aim to replicate this interaction)

Question 2

What is the first line regime for T1DM treatment ?

Answer 2

Basal-bolus regime - this is a rapid acting insulin given before having a meal and a long acting insulin given once or twice per day

Question 3

What are the rapid acting insulins ?

Answer 3

Humalog (insulin lispro), Novorapid or Apidra (HAN-solo)

Question 4

What are the long-acting insulin analogues ?

Answer 4

Lantus or levemir

Question 5

What are the short acting insulins ?

Answer 5

Humulin S, Actrapid, Insuman rapid (HIA to remember them)

Question 6

What are the intermediate acting insulins?

Answer 6

Insulatard, Humulin I (isophane human), Insuman basal

Question 7

What are the rapid acting analogue intermediate mixtures ?

Answer 7

Humalog mix 25/50 or Novomix 30

Question 8

What are the short acting intermediate mictures ?

Answer 8

Humulin M3. Insuman comb 15,25,50

Question 9

What is the importance of carb counting ?

Answer 9

Because peoples carb intake varies from meal to meal so need to tailor there rapid/short acting insulin intake per meal to the carbs in that meal

Question 10

What is the ratio of units of insulin to grams of carb ?

Answer 10

1 unit to 10grams of carb

Question 11

What is an insulin pump ?

Answer 11

• Medical device which gives a continuous administration of short acting insulin S/C
• Delivers a background insulin dictated by basal rate

Question 12

What are the different ways in which you can evaluate metabolic control of diabetes ?

Answer 12

• Home blood glucose (fingerstick tests)
• Urine testing (glucose/ketones)
• Glycated haemoglobin (HBA1c)
• Continuous glucose monitor

Question 13

What is a draw back of fingerstick tests in blood glucose monitoring ?

Answer 13

They only provide a snapshot of control not able to see the whole picture with them

Question 14

What is a benefit of HBA1c in blood glucose monitoring ?

Answer 14

Provides a measure of average blood glucose over a prolonged time - 6-8 weeks

Question 15

What are some of the limitations/problems encountered with insulin therapy ?

Answer 15

No therapy is able to replicate normal human insulin physiology

Normal human pancreatic insulin secretion - is direct into the portal blood stream, rapidly prevents post-meal hyperglycaemia and is rapidly cleared

Insulin therapies - Injected in S/C tissue. peak too slow to prevent post-meal hyperglycaemic spike, have a slow clearance

Question 16

What are some of the factors which effect insulin absorption/action ?

Answer 16

• Injection accuracy
• Leakage at injection site
• Lipohypertrophy developing and affecting absorption at site

Question 17

What are some of the safety issues with insulin ?

Answer 17

• Potential wrong dosage given - due to misreading e.g. 10U can be read as 100 and patient is then given 100 units. This is why abbreviations such as U and IU are never used
• Insulin omission e.g. if a patients unwell
• Wrong insulin type given - the names all look very similar e.g. Humalin I and Humalin S

Question 18

What are the principles of insulin dose adjustment ?

Answer 18

• Review glycaemic control and adjust to optimise control
• Insulin adjustment can precipitate hypoglycaemia
• Do not omit insulin if hypoglycaemic, treat the hypo and administer insulin as usual

Question 19

What are the blood glucose targets in insulin treatment ?

Answer 19

• Pre-prandial - 4-7mmol/L
• Post meal - < 10 mmol/L
• HBA1c 48 mm

Question 20

What are the key points about insulin administration ?

Answer 20

1. Verify amount of insulin with patient or if not possible with a colleague as you must ALWAYS have 2nd independent check of insulin doses
2. Only use specific insulin syringes
3. Glucose should be used for all IV insulin infusions except patients admitted with DKA

Question 21

Note the I, S and M when talking about Humulin stand for short, intermediate and mixed

Answer 21

.

Question 22

When do you give IV insulin ?

Answer 22

• DKA
• Role in hyperosmolar hyperglycaemic state (HHS)
• Acute illness
• Fasting patients who are unable to tolerate oral intake

Question 23

What monitoring is required for patients receiving IV insulin ?

Answer 23

• Hourly blood glucose monitoring - aim for a BG of 5-12 mmol/L
• Check ketones if BG > 12
• Check Us and Es at least daily