BC ADM Blood Glucose Monitoring 4 — Questions and Answers
Question 1: During exercise, a patient's CGM shows glucose dropping from 140 to 95 mg/dL over 30 minutes with a downward arrow. Per ADA exercise guidelines, what should the patient do?
- Stop exercise immediately and call 911
- Consume 15–30g fast-acting carbohydrates and continue or pause exercise (Correct answer)
- Administer glucagon
- Increase basal insulin infusion
Correct answer: Consume 15–30g fast-acting carbohydrates and continue or pause exercise
ADA exercise guidelines recommend consuming 15–30g of fast-acting carbohydrates when glucose falls rapidly during exercise to prevent hypoglycemia.
Question 2: Which statement about continuous glucose monitor (CGM) sensor accuracy during the warm-up period is correct?
- CGM sensors are fully accurate immediately upon insertion
- Most CGM sensors require a 1–2 hour warm-up before providing reliable readings (Correct answer)
- Warm-up periods only apply to implantable CGM devices
- SMBG calibration eliminates the warm-up accuracy limitation
Correct answer: Most CGM sensors require a 1–2 hour warm-up before providing reliable readings
Most CGM sensors require a 1–2 hour initialization/warm-up period after insertion before glucose readings are sufficiently accurate for clinical use.
Question 3: A hospitalized patient on insulin drip has fingerstick BG of 52 mg/dL but appears clinically well without symptoms. What is the most appropriate next step?
- Repeat the fingerstick immediately and treat if confirmed (Correct answer)
- Administer IV dextrose without repeating the test
- Discontinue insulin and observe
- Check A1C to assess chronic glycemic control
Correct answer: Repeat the fingerstick immediately and treat if confirmed
In the hospital, a low fingerstick result without symptoms warrants immediate repeat testing to confirm hypoglycemia before treatment, as capillary samples can yield erroneous results.
Question 4: Which CGM alarm threshold setting is most appropriate to help a patient with hypoglycemia unawareness?
- Low alarm at 60 mg/dL
- Low alarm at 80 mg/dL with a predictive low alert at 20 minutes (Correct answer)
- High alarm at 200 mg/dL only
- Alarm-free use to avoid alarm fatigue
Correct answer: Low alarm at 80 mg/dL with a predictive low alert at 20 minutes
Setting a low alarm at 80 mg/dL with a predictive alert provides early warning for patients with impaired hypoglycemia awareness, allowing intervention before glucose falls to dangerous levels.
Question 5: A patient's CGM Mean Absolute Relative Difference (MARD) is reported as 12%. What does this indicate?
- The sensor is inaccurate and should be replaced
- On average, CGM readings differ from reference blood glucose by 12% (Correct answer)
- 12% of readings are in hypoglycemic range
- The sensor requires calibration immediately
Correct answer: On average, CGM readings differ from reference blood glucose by 12%
MARD is the standard CGM accuracy metric; a 12% MARD means CGM values deviate from reference glucose by an average of 12%, which is within acceptable clinical accuracy range.
Question 6: When counseling a patient about blood glucose testing technique, which error most significantly affects SMBG accuracy?
- Testing at room temperature below 65°F (18°C)
- Using the first drop of blood after vigorous squeezing of the fingertip
- Testing within 1 hour of a meal
- Using alcohol to clean the site and testing before it dries (Correct answer)
Correct answer: Using alcohol to clean the site and testing before it dries
Residual alcohol on the fingertip dilutes the blood sample and can cause falsely low readings; the site must be completely dry before lancing.
Question 7: Which of the following best defines 'time below range' (TBR) Level 2 in the CGM consensus targets?
- Glucose <70 mg/dL
- Glucose <54 mg/dL (Correct answer)
- Glucose 54–69 mg/dL
- Glucose <40 mg/dL
Correct answer: Glucose <54 mg/dL
TBR Level 2 is defined as glucose <54 mg/dL, representing clinically significant hypoglycemia; the target is <1% of readings in this range.
BC ADM Blood Glucose Monitoring 4
During exercise, a patient's CGM shows glucose dropping from 140 to 95 mg/dL over 30 minutes with a downward arrow.
Per ADA exercise guidelines, what should the patient do?