How Is a CGM Inserted? Step-by-Step Guide

Continuous Glucose Monitoring (CGM) devices and systems have ushered in a new era in the treatment of diabetes, giving accurate, real-time glucose measurements that enable a patient to preempt the highs and lows.

So, how does this little device ultimately get under your skin, and does it hurt?

Not a surprise, the answer is that the CGM insertion process is quick and easier than most expect. In this article, I describe the CGM insertion process step-by-step, so you can see for yourself how easy and empowering a CGM can be.

What is CGM Insertion?

CGM insertion is the procedure to insert a small flexible sensor just under your skin. The sensor will measure glucose levels in the interstitial fluid (the fluid between your cells) and wirelessly send this data level to a receiver, smartphone, or insulin pump for live tracking.

Typically, the user inserts the CGM sensor using a pre-loaded applicator, which inserts the sensor with little discomfort. The sensor is worn for a few days to two weeks (depending on the device), continuously transmitting data so you can better manage your diabetes without “fingersticks.”

How to Prepare for CGM Insertion?

With enough prep work, you can optimize sensor performance, reduce irritation to your skin, and arrive at your experience with less hassle overall.

Choose the Right Location

Recommended sites will vary by manufacturer, but the belly and back of the arm’s upper area are the most common because of the fat content, as well as convenience. Do not place the sensor where you have moles, scar tissue, or skin folds, to give the best opportunity for readings and wearing comfort.

Clean and Dry Your Skin Thoroughly

Use soap and water to clean the site, then pat dry with a towel. Never use alcohol unless specifically stated by your CGM manufacturer. There is a possibility that some adhesives may not bond well with alcohol-cleaned skin. You must not apply lotion or oil to the skin first ever.

Gather All Necessary Supplies

Make sure you have a CGM sensor and applicator, transmitter (if separately purchased) and your monitor/app in close proximity. If you feel like you may need a sustainable adhesive patch or barrier wipe, have those on hand also to help maximize your experience. 

Stay Calm and Relaxed

Tension may cause you to be more aware and sensitive throughout the process. Breathe deeply for a few moments and visualize the result. Remind yourself that most people say the insertion is way easier than they ever imagined.

7 Easy Steps for CGM Insertion 

Step 1: Inspect the Sensor and Applicator

• First, carefully take out the sensor and applicator.
• Confirm there is no damage to the packaging, or any other items are missing.
• Do not touch the sensor filament or needle.
• Read the instructions for your model before substituting your existing device. Each of the brands can be slightly different.

These steps take place of the standard hygiene procedures. Once you remove the packaging, you are avoiding damaging the sensor even before you insert it.

Step 2: Position the Applicator on the Chosen Site

With the insertion site cleaned and dried, carefully place the applicator flat against the skin.

• Press the base of the applicator against your skin where you want to insert it.
• Keep the applicator steady to have the accurate placement of the sensor.

If you are nervous about accurately placing the device you could practice with a demo (or dummy) device if available.

Step 3: Deploy the Sensor

This is where the sensor is inserted.

• Push the button or method to insert the filament under your skin?
• The device is automatic and is designed to make this process as pain-free as possible.

Most users describe it as a small pinch or flick. Definitely not as painful as a normal injection.

Step 4: Secure the Sensor with Adhesive

• Once inserted, press around the sensor to make sure the built-in adhesives work. 
• For extra durability, and if you sweat a lot or are active, use additional patches or over-bandages. 

This step is important in preventing the sensor from falling off sooner than intended. 

Step 5: Attach the Transmitter

• If the transmitter is separate from the sensor, align and click into place. 
• You should hear or feel a soft click when attached properly. 

After then, your app or receiver will wirelessly receive your blood sugar levels.

Step 6: Activate the Sensor and Calibrate (If Needed)

• Now launch the receiver or your CGM app. To begin a new sensor session, adhere to the instructions and prompts. 
• The majority of CGMs need to warm up before they can provide readings. Typically, this warm-up lasts one to two hours.
• Some devices, such as older Dexcom models, require human fingerstick calibration of the sensor. 

It is crucial to do these steps, otherwise, the readings can be inaccurate, or you’ve wasted time trying to track your trends. 

Step 7: Monitor for Initial Discomfort or Skin Reactions

• Tenderness, or light redness, is normal. 
• Try to not bump, touch, or scratch the site.
• If it starts itching, swelling, or shows any signs of infection, you do need to see your provider as soon as you can.

Rotating sites and using barrier wipes regularly can help to reduce the symptoms of skin reactions or irritation especially if you are wearing a CGM for an extended period of time.

Best Practices for CGM Insertion: Tips from Experts

Would you like even better results with even fewer issues? Consider the following best practices:

• Rotate your insertion sites regularly—don’t use the same site frequently—so that you can avoid skin breakdown or scar tissue.
• Do not insert on tattooed skin or scarring skin, which may affect readings.
• Use adhesive enhancers or skin barrier wipes when using sites on oily or sensitive skin.
• Consider inserting a sensor when activity is low or at a time of day when activities are less likely—like early in the morning. In this manner, the adhesive will have enough time to solidify.
• Engaging in mindful/affected distractions (like music or breathing) can reduce anxiety; especially useful when inserting a sensor in children, or for first-time users.

Troubleshooting CGM Insertion Problems

Each time when inserting a new CGM sensor, you will inevitably encounter issues. Only a handful of the typical issues and their fixes are listed below:

• Sensor is not sticking: Clean the area again, don’t rush the drying, and consider proactive skin prep or better adhesive patches.
• Pain persists: You may have been near a nerve or should ask your healthcare provider to check your technique.
• Sensor falls out early: Always consider tight fitting clothes, exposing, or poor adhesion. Consider overlay patches.
• Inaccurate readings: Make sure the sensor is fully inserted, check the calibration if used and avoid inserting near a navel or bony site.

When to Replace or Remove Your CGM Sensor

Each manufacturer determines a usage period, with most products falling in the 7-14 day range.

Do not exceed the recommended period, or it will impact sensor accuracy.

Have your next sensor ready to go so there is no gap in the data.

To remove the sensor, do so gently—using adhesive remover will lessen the risk to the skin.

Check the site for any redness, swelling, or sticky adhesive burns.

Rotate sites to allow full healing of skin while receiving continuous data.

Importance of Proper Insertion Technique

Proper technique is not just a formality—it is essential to successful glucose monitoring.

• Incorrect insertion can lead to missed highs/lows or premature sensor failure.
• Placing the device in a hygienic manner limits the risk of infection.
• More of a “comfortable” position leads to more consistent wear and less disrupted use.

If you cannot find a place to get a proper demo of the device, ask your healthcare team.

How Healthcare Providers Can Assist with CGM Insertion

You are not alone on this journey. We believe medical professionals can help even in ways you may not realise:

• Certified diabetes educators are trained in teaching proper insertion techniques.
• Some clinics offer practice sessions or demos.
• Healthcare providers can assess your skin type and use their experience to help locate the best sites for insertion.
• Scheduled visits allow for periodic follow-up visits, which increases your comfort with the device and your confidence in using it.

Support from professionals can help change hesitation into a habit.

How to Adapt to CGM Insertion for Children and Seniors

Age-specific considerations can mitigate barriers to successful CGM use.

• For children: Parents or caregivers install a CGM by using comforting strategies and distraction methods.
• For Seniors: Reduced physical abilities or reduced vision might require support from a caregiver or assistive tools.

In both cases, extra instruction and compassion will enhance the experience.

With some practice, CGM DG tools can be safely installed regardless of age.

FAQs 

1. Does CGM insertion hurt?

The overwhelming response is no. People tend to say it feels like a quick pinch, which is certainly much less painful than fingersticks or injections.

2. How long can I wear a CGM sensor?

Most CGM sensors last from 7 to 14 days depending on the CGM type (e.g. Dexcom, Freestyle Libre, Medtronic).

3. Can someone swim or shower with a CGM?

Yes. Most CGMs we are using now are designed to be water-resistant. Please consult your CGM user guide to obtain the time and depth limits for your device.

4. What should I do if the sensor falls off?

Reapply the sensor using medical tape. If the sensor becomes dislodged during the CGM session, you need to replace the sensor with a new sensor so you can resume monitoring as intended.

5. Is it safe to insert a CGM at home?

Yes! These devices were designed to be installed at home by family members. Example, it is very helpful and effective to have professionals sharing their knowledge with a family member to get the new experience started.

Conclusion

Getting started with CGM can seem daunting, but when you have the right tools, techniques, and support the insertion process will become second nature. You’ll not only improve your glucose data but also help ensure peace of mind and better long-term health. 

Healify Now is ready to help you–whether you are using CGM for the first time or simply want to improve your routine. Our team will work with you individually, live and personalized, to ensure each insertion is as easy and comfortable as possible. 

Contact us today for your free consultation, and let’s empower your diabetes care together!

Evelyn Brown