CHAPTER 19 · TECH & MONITORING
DIABETES TECH TOOLS
How CGMs and insulin pumps actually work, and how to wear one.
Technology can make living with diabetes easier and safer. Tools like continuous glucose monitors (CGMs) and insulin pumps help you keep your blood sugar levels steady and avoid serious highs and lows.
Continuous Glucose Monitoring (CGM)
What a CGM does and where it sits.
📡 What CGMs do
- Track your blood sugar levels and help keep them within target ranges.
- Reduce the risk of dangerously low (hypoglycemia) or high (hyperglycemia) blood sugar.
- Help calculate how much insulin you need.
- Reduce the need for regular finger pricks.
📍 Where it sits
- Usually placed on your skin, upper arm or abdomen.
- Don’t remove it unless it needs to be changed.
- Needs to be changed about every 10 to 14 days, depending on the brand.
- Changing parts is quick and easy, you’ll learn from your medical team, and you can also find step-by-step videos online.
Two main types of CGM
For a deeper comparison, see Chapter 18: Finger Prick & CGM.
🔄 Real-time CGM
- Measures blood sugar every 1 to 5 minutes.
- Sends readings automatically to your phone or receiver: no scanning needed.
- More sophisticated alarms for highs and lows.
- Components: a sensor with a transmitter, plus a smartphone or receiver that displays the data. Newer devices often combine the sensor and transmitter into one all-in-one unit, instead of a separate clipped-on transmitter.
📲 Intermittently scanned CGM
- Measures blood sugar every few minutes too.
- Traditionally needs scanning of the sensor to see and save results.
- Components: a sensor-and-transmitter combo (usually on the upper arm) and a reader, either a dedicated handheld device or a smartphone.
- The line is blurring, some of the newest devices and apps can stream readings continuously too, but most still rely on scanning, and alarm features tend to be more limited than on real-time CGMs.
Insulin Pumps
Small devices that deliver insulin throughout the day.
💉 The basics
- Usually used together with CGMs.
- Small devices that deliver rapid-acting insulin continuously over 24 hours.
Placing your pump
A few rules of thumb that make wearing it easier.
📏 Where it goes
- Pinch an inch: place it where you can pinch a small pad of skin.
- Keep distance: don’t place it within 2 inches of a CGM.
- Avoid problem areas: thickened skin, swelling, or lumps (using the same spot over and over causes these fatty lumps).
How insulin pumps work
How they work, and how they make daily life easier.
⚙️ How it works
- Use only rapid-acting insulin.
- Deliver small doses throughout 24 hours (basal insulin).
- Automated insulin delivery (AID) or hybrid closed loops are pumps that work together with a CGM and adjust your background insulin automatically, see Chapter 18: Finger Prick & CGM.
✨ How it helps
- Can help calculate insulin needs based on carb intake.
- Recommend doses you can confirm or adjust.
- Deliver correction doses if your blood sugar is too high.
- Send reminders so you don’t forget your mealtime insulin.
- For more on the medications themselves, see Chapter 12: Insulin & Medication.
Things to remember
A few practical points worth keeping in mind.
⚠️ Good to know
- You can remove pumps if needed.
- Once removed, you’ll be without insulin. Don’t leave it off for long: blood sugar rises and ketones can build within hours, with a risk of DKA, a medical emergency.
- Some pumps are not waterproof.
- Pumps and sensors must not go through airport X-ray (see the Travel Checklist), and they need to come off for MRI and CT scans.
Pump types
Insulin pumps come in 2 main types, and each works a little differently in how it delivers insulin.
🔌 Tethered (tubed) pump
- Includes a pump, a tube, and an infusion set.
- A soft tube/cannula under the skin delivers the insulin.
- Pump can be clipped to clothing, kept in a pocket, strapped to your leg, or placed between bra cups.
- Change cannula/infusion set usually every 2–3 days.
- Pump itself can last for years.
- Need to change the insulin reservoir regularly.
- Some pumps are waterproof, others aren’t.
🩹 Patch pump
- Pump attaches directly to the skin.
- Includes both reservoir and cannula in one unit.
- Controlled with a handheld device or phone.
- Worn on areas like upper arm, abdomen, hip, buttock, or thigh.
- Units are usually changed about every 3 days.
- Often waterproof (you can swim and bathe with them).
Everyday device challenges
Wearing something on your skin all the time comes with a few practical questions.
🩹 Handling everyday device challenges
- Skin irritation and eczema under a sensor or infusion set are common. They can often be avoided, and usually settle, with correct placement, changing the spot every time, good skincare, taking the device off gently, and letting the skin heal before you use that area again.
- Prep wipes, barrier dressings and gentle adhesive removers are made for exactly this. If irritation keeps coming back anyway, tell your team, it can sometimes be an allergy to the adhesive.
- Showering: most devices are waterproof. Keep them out of the direct jet of a high-pressure showerhead, and pat the skin dry instead of rubbing, so the adhesive stays put.
- Covering up: if your device is not waterproof, or you prefer it covered, overpatches and large adhesive bandages are made for this.
- Sport: a compression sleeve or arm sleeve is another option, on its own or over one of the covers above.
A note on this chapter: details vary by brand and change over time. For anything specific to your device, follow your medical team’s guidance and your manufacturer’s instructions.
Before you go. TeenHealthInsight is a health education website, not a substitute for medical advice. Any questions or worries about your medication, devices, or daily care should be brought to your doctor. Learn here, decide there, always loop in your diabetes team before changing anything you do.