Continuous Glucose Monitoring

Diabetes Management Evolution Diabetes Management Evolution

Insulin Delivery

Glucose Monitoring

2000 First CGM system

2006

Paradigm REAL-Time, combining Insulin Pump and CGM

1983 First Minimed

Pump-502

1978First Insulin

Pump1920s

Insulin Injections

2005-2007Real-time CGM

Urine Testing

1977 Blood Glucose

Meter

1999 First AnimasPump-R1000

2012 Dexcom G4

Navigator

NOTE: Only the Medtronic Real-time CGM is approved for use in children and adolescents in the U.S.

Why Continuous Glucose Monitor?

• Prevention of hypoglycemia

• Prevention of hyperglycemia

• Pattern assessment

• Basal Testing

• Assess the impact of food on blood glucose

• Assess the impact of exercise on blood glucose

• Behavior modification tool

• Alerts/Alarms: Safety, peace of mind…

Hypoglycemia in Children and Adolescents

• 657 children followed for 3 years

• 8.5% had severe (seizure/coma) hypoglycemia

• 27% had moderate (required assistance) hypoglycemia

• 75% of seizures occurred at night

• Recent CGM data shows seizure may require prolonged severe hypoglycemia prior to event

Davis EA, et al. “Hypoglycemia: Incidence and clinical predictors in a large population-based sample of children and adolescents with IDDM” Diabetes Care 1997;20:22-25.

17 y.o. Female, A1C 6.2%, in Study 3 Months

17 y.o. Female, A1C 6.2%

Seizure

14 y.o. male A1C 6.6%, Crews (rowing team) in PM

5/16/06

5/27/06

Camp Study: Duration of hypoglycemia with and without remote monitoring in 13 y.o. male on MDI

“Insulin Rx” is glucagon

No Remote Monitoring<70 mg/dl = 350 minutes<50 mg/dl = 305 minutes

Remote Monitoring<70 mg/dl = 110 minutes< 50 mg/dl = 10 minutes

0

50

100

150

200

250

300

350

400

Fingerstick Measurement

Glu

cose

(mg/

dl)

Breakfast8:30 am

Lunch12:00 noon

Dinner6:00 p.m.

Bedtime10:30 p.m.

Insulin Bolus

Target Range

Daily Patient Log

Target Range

Daily Patient Log and Sensor Data

0

50

100

150

200

250

300

350

400

Glu

cose

(mg/

dl)

Breakfast8:30 a.m.

Lunch12:00 noon

Dinner6:00 p.m.

Bedtime10:30 p.m.

Sensor Measurement

Insulin Bolus

Fingerstick Measurement

What’s the Difference??

1. 100 mg/dL

OR

2. 100 mg/dL dropping at rate of >2 mg/dL/min

CGM adds an additional dimension, the rate of change and direction of change.

Practical Application:Real Life Experience

“Paula’s Pearls”

Pearl # 1: Match Device to Patient Needs

Size…real estate issues

Transmitter Range

Transmitter Range:

I can’t find you!!

Pearl # 2 : Match Insertion Approach…Ouch!

◊ Use numbing cream: lidocaine topical

Ela-Max cream

EMLA cream

◊ Use soap and water to wipe off cream

then clean with alcohol

Tape Issues: How do we get this thing to stay on??

• IV 3000, Tegaderm, Hy-Tape

• Coban

• IV prep- avoid at sensor insertion area

• “Sandwich”/layer tape

• Tape Allergies…Ugh!

Pearl # 3: Teach, Teach and Teach Again!

Sensor Lag Time

Calibration

Trend Arrows

Glucose Trends/Patterns

Sensor Lag Time: Why doesn’t the sensor match my fingerstick reading?

• There is a 10-20 minute lag time between interstitial fluid (ISF) glucose and BG

• Lag occurs with ALL subcutaneous sensors

• CGM is a trending device, NOT a treatment device

Sensor Lag

Time (minutes) (0 = start if meal)

-40 -20 0 20 40 60 80 100 120 140

Blo

od G

luco

se (

mg/

dl)

0

100

200

300

400

500

Freestyle Sensor

Sensor Lag

Fingerstick Capillary Glucose (SMBG)

Interstitial Fluid Glucose (CGM)

QUESTION:When will the ISF glucose and the BG value be the most similar/closest?

When BG is stable/not fluctuating rapidly

QUESTION:When using a CGM, when should the patient test their BG with a fingerstick?

1. Before all treatment decisions and insulin

2. To verify symptoms of hypoglycemia

3. Before driving

Calibration: When to calibrate?

• The accuracy of all the CGM’s are dependent on the calibration phase

• Devices calibrate in 1-2 hours

• Must do a fingerstick BG to calibrate

• Do NOT calibrate when the BG is changing rapidly

Calibration: When is the best time to calibrate?

• When BG is not changing rapidly

Trend Arrows:

• Show the direction of change

• Provides information on the rate-of-change

Activity

• Table teams review the CGM downloads

• What do you see?

• What don’t you see?

• Recommendations/Suggestions?

Glucose Trends – CGM Report

Post-breakfastexcursion

Post-breakfastexcursion

Nocturnal lows

Glucose Trends – CGM Report

Pearl # 4: Respond to Data

1. Change behavior!• Pre-bolus

• Less carbs at breakfast

• Assess food impact

2. Check basal rates

3. Use alarms

Pearl # 5: Who should wear a CGM?

• MOTIVATED patients/parents!

• Those willing and able to be educated on the device

• Those who are willing to look at and respond to the data!

• Those with realistic expectations and who can handle a potentially “rocky” start

CGM REPORTS

Report #1: Patience is important!

Report # 2: Missed Meal Bolus

Report # 3: Near perfection! A1C 6.1%

Report # 4: Failure to acknowledge alarms and using pump suspend

Report # 5: Pump site failure

Pump site failure Insulin via syringe Insulin via syringe

“NAKED DIABETES!”