BC ADM Insulin Therapy 3 — Questions and Answers
Question 1: A patient on basal-bolus insulin therapy has consistently elevated 2-hour postprandial glucose after dinner but acceptable fasting and pre-meal values. The most appropriate adjustment is:
- Increase the morning basal insulin dose
- Increase the pre-dinner rapid-acting insulin dose (Correct answer)
- Add a bedtime snack with NPH
- Switch basal insulin to twice-daily dosing
Correct answer: Increase the pre-dinner rapid-acting insulin dose
Isolated postprandial hyperglycemia after a specific meal indicates insufficient mealtime (prandial) insulin coverage for that meal.
Question 2: Which factor most significantly reduces insulin absorption rate from a subcutaneous injection?
- Injection into the abdomen rather than the thigh
- Injection into a lipohypertrophic site (Correct answer)
- Use of a shorter (4 mm) pen needle
- Rotating injection sites within the same region
Correct answer: Injection into a lipohypertrophic site
Lipohypertrophic tissue is fibrotic and poorly vascularized, substantially slowing and unpredictably altering insulin absorption.
Question 3: The 'dawn phenomenon' in diabetes refers to:
- Nocturnal hypoglycemia followed by morning hyperglycemia (Somogyi effect)
- Early morning hyperglycemia due to physiologic rise in counter-regulatory hormones (Correct answer)
- Insulin resistance that develops only during sleep
- Hypoglycemia occurring at approximately 3:00 AM
Correct answer: Early morning hyperglycemia due to physiologic rise in counter-regulatory hormones
The dawn phenomenon is caused by early-morning surges in growth hormone and cortisol that increase hepatic glucose production, raising fasting blood glucose.
Question 4: A patient using CSII (insulin pump) therapy develops diabetic ketoacidosis. The most likely pump-related cause is:
- Excessive basal insulin delivery overnight
- Catheter occlusion or site failure interrupting insulin delivery (Correct answer)
- Accidental double bolusing at mealtime
- Insulin degradation due to cold temperature in the reservoir
Correct answer: Catheter occlusion or site failure interrupting insulin delivery
Catheter kinking, dislodgment, or site occlusion can completely interrupt subcutaneous insulin delivery, rapidly leading to DKA since pumps use only rapid-acting insulin.
Question 5: When calculating an insulin-to-carbohydrate ratio (ICR), the '450 rule' is used instead of the '500 rule' in which scenario?
- When the patient uses NPH as basal insulin
- When the patient uses regular (short-acting) insulin for meals (Correct answer)
- When the patient has gastroparesis
- When total daily dose exceeds 100 units
Correct answer: When the patient uses regular (short-acting) insulin for meals
The 450 rule is applied when regular (human) insulin is used for meal coverage because its slower onset requires a slightly different ratio than rapid-acting analogs.
Question 6: Pramlintide (Symlin) is used as an adjunct to mealtime insulin primarily because it:
- Increases endogenous insulin secretion postprandially
- Suppresses glucagon, delays gastric emptying, and reduces appetite (Correct answer)
- Directly blocks hepatic glucose production at meal times
- Enhances insulin receptor sensitivity in skeletal muscle
Correct answer: Suppresses glucagon, delays gastric emptying, and reduces appetite
Pramlintide is an amylin analog that suppresses postprandial glucagon secretion, slows gastric emptying, and promotes satiety, reducing postprandial glucose excursions.
Question 7: A type 1 diabetes patient on MDI reports consistent hypoglycemia between 2–4 AM with rebound hyperglycemia by 7 AM. The most appropriate initial intervention is:
- Increase bedtime basal insulin to prevent the rebound
- Reduce the evening basal insulin dose and verify with nighttime CGM (Correct answer)
- Add a bedtime snack with rapid-acting insulin coverage
- Switch to twice-daily NPH to smooth overnight glucose
Correct answer: Reduce the evening basal insulin dose and verify with nighttime CGM
Nocturnal hypoglycemia followed by rebound suggests excess evening basal; reducing it and monitoring with CGM confirms the pattern before further adjustments.
BC ADM Insulin Therapy 3
A patient on basal-bolus insulin therapy has consistently elevated 2-hour postprandial glucose after dinner but acceptable fasting and pre-meal values.
The most appropriate adjustment is: