For individuals living with diabetes, an upcoming medical procedure—whether a minor outpatient surgery, a diagnostic imaging session, or a major operation—introduces unique challenges. Blood glucose levels can swing unpredictably due to fasting, stress, anesthesia, and changes in medication schedules. Mismanagement of diabetes around procedures increases the risk of complications such as delayed wound healing, infections, hypo- or hyperglycemic episodes, and even extended hospital stays.

Fortunately, modern diabetes management tools now allow for data-driven preparation. One of the most powerful platforms is Medtronic CareLink, a secure, web-based system that aggregates data from insulin pumps, continuous glucose monitors (CGMs), and blood glucose meters. By uploading and reviewing your device data through CareLink, you can create a detailed picture of your recent glycemic trends, insulin usage, and device performance. This information enables both you and your healthcare team to make informed decisions about insulin adjustments, timing of the procedure, and perioperative glucose targets.

The purpose of this guide is to show you exactly how to use CareLink to prepare for diabetes-related medical procedures. You will learn step-by-step preparation techniques, best practices for data sharing, and strategies for avoiding common pitfalls that could derail your procedure. Whether you are a Medtronic pump user, a Guardian CGM user, or someone who uses both devices together, CareLink offers a centralized approach that simplifies coordination with your endocrinologist, surgeon, and anesthesiologist.

CareLink is a secure online platform developed by Medtronic that allows users to upload data from compatible diabetes devices, including the MiniMed™ series insulin pumps (630G, 670G, 770G, 780G), Guardian™ Connect and Guardian™ Sensor 3 CGMs, and select blood glucose meters. Once uploaded, the data is displayed in clear, interactive reports that show glucose readings, insulin delivery, sensor trends, and alarms. These reports can be viewed by the patient and shared with healthcare providers through a secure portal.

CareLink is not just a passive record; it actively analyzes patterns. For example, it can identify times of recurrent hypoglycemia, insulin stacking, or suboptimal basal rates. It also tracks carbohydrate entries and corrections if you use the SmartGuard™ or Advanced Hybrid Closed-Loop features. This analytical capability makes CareLink an indispensable resource when preparing for a medical procedure, because it allows your care team to quickly assess your current diabetes control and make real-time adjustments to your therapy plan.

Many people with diabetes still rely on paper logs or manual spreadsheets to track glucose readings and insulin doses. While these methods can work, they often miss important data points such as overnight trends, daily fluctuations, and device malfunctions. CareLink automates this process: it can capture 288 sensor readings per day with a CGM, plus pump history that includes every bolus, basal rate change, and alarm event. This rich dataset reduces the chance of human error and provides a level of detail that can be critical when planning a procedure that involves fasting, sedation, or changes in insulin sensitivity.

Moreover, CareLink synchronizes data across multiple devices. For instance, if you use both a MiniMed pump and a Guardian CGM, CareLink will correlate insulin delivery events with glucose readings, helping you see how a meal bolus at noon affected your glucose two hours later. This integration is particularly valuable before a procedure because it lets you judge whether your current insulin-to-carb ratios and correction factors are still working—or whether they need temporary adjustment.

Security and HIPAA Compliance

Because CareLink contains sensitive health information, Medtronic ensures that the platform is HIPAA-compliant. Data transmitted from your device to CareLink is encrypted, and you control who has access to your account. When you share your reports with a healthcare provider, they must also have authorised access to the CareLink clinic portal. This protects your privacy while still enabling seamless collaboration. For pre-procedure planning, this means you can confidently upload and share data without worrying about unauthorised access.

Step 1: Gather Your Devices and Confirm Compatibility

Before you can upload data, you need to confirm that your devices are compatible with CareLink. Most Medtronic pumps manufactured after 2015 are supported, including any MiniMed model with the 3.0A, 3.0B, or later firmware. Guardian CGM transmitters should have the latest software. If you are unsure, check the official Medtronic CareLink page for a list of compatible devices.

Also, gather your USB connection cable (if using a pump that connects via MiniMed USB adapter) or set up the web uploader tool if your pump supports Wi-Fi or Bluetooth upload. Many newer pumps allow direct upload through the CareLink mobile app. For this preparation, it is best to upload from a computer with a stable internet connection, as the larger reports are easier to review on a screen.

Step 2: Download Recent Data from Your Devices

CareLink can pull data directly from your pump and CGM when you connect them. However, it is a good practice to first do a manual download from your pump using the Medtronic Diabetes software or the pump’s built-in history to ensure all data is fresh. Some users find that uploading after a sensor change or after a full day of data gives a more complete picture. Ideally, you should gather data covering at least 7 to 14 days before the procedure. This window captures both weekday and weekend patterns, which often differ due to activity levels, meal timing, and stress.

If you use a Guardian CGM, make sure the sensor is calibrated according to the manufacturer’s instructions. Inaccurate sensor readings can mislead your preparation. Medtronic recommends calibrating when glucose is stable (not rising or falling rapidly) to ensure the sensor is reliable.

Log in to your CareLink account at carelink.minimed.com. Click on the "Upload" button (if not automatic) and follow the prompts to connect your pump via USB or Bluetooth. The upload process typically takes 1 to 3 minutes. Once complete, CareLink processes the data and generates reports that you can view immediately.

If you are using the CareLink mobile app on your smartphone, you can also upload via Bluetooth, but be aware that some pumps require the desktop version for the most complete report generation. For pre-procedure preparation, the web version offers richer analytics, such as the Daily Patterns, Sensor Overlay, and Sensor Daily Graphs that help identify trouble spots.

Step 4: Review Your Data for Key Indicators

Now comes the critical part: understanding what the data says about your readiness for a medical procedure. Look for these patterns in your CareLink reports:

  • Hypoglycemia frequency: How many times have you experienced low glucose events in the past week? Are they overnight? During exercise? If you need to fast for the procedure, your risk of hypoglycemia may increase. Share these patterns with your provider so they can adjust basal rates or recommend temporary insulin suspension.
  • Hyperglycemia trends: Is your glucose consistently high in the morning (dawn phenomenon)? Do you have unexpected spikes after meals? High glucose can impair immune function and wound healing, so your team may want to tighten control before the procedure.
  • Insulin usage: Review total daily insulin (TDI) trends. Large variations from day to day may indicate that your current settings are not stable, which can complicate perioperative insulin management. Your provider may ask you to standardise your basal rates or carb ratios a few days before the procedure.
  • Sensor accuracy: Check the Mean Absolute Relative Difference (MARD) if available. If your CGM appears to be off by more than 10% compared to fingersticks, you may need to recalibrate or change the sensor before the procedure to avoid false alarms.

Take screenshots or print the reports that show the past 3-7 days. If you see any alarming patterns—like frequent severe lows or persistent highs above 300 mg/dL—contact your endocrinologist immediately. Do not wait until the day before the procedure.

Step 5: Share Your Data with Your Healthcare Team

CareLink makes sharing straightforward. In the Reports section, you can email a PDF or generate a secure link that your provider can access. Alternatively, your healthcare provider may already have a CareLink clinic account. They can then view your data on their end without you sending anything. It is wise to call your provider’s office a week before the procedure and ask: "Do you have access to my CareLink data? Should I share it in a specific way?" Many endocrinologists prefer to see at least 14 days of data, so plan accordingly.

If your surgeon or anesthesiologist is not a diabetes specialist, it may help to provide a one-page summary generated from CareLink. This summary should include your device type, current insulin settings, recent glucose range, and any automated insulin delivery features (like SmartGuard) that may need to be turned off during the procedure. A resource from Diabetes UK on surgery and diabetes can also help you frame the conversation with non-specialist providers.

Advanced Preparation Strategies

Adjusting Pump Settings Before the Procedure

Using the data from CareLink, you and your endocrinologist can decide whether to modify your pump settings in the few days leading up to the procedure. For example:

  • Basal rates: If fasting is required, the insulin requirement typically drops. CareLink data can help determine a temporary basal profile that reduces risk of hypoglycemia during the fast. Some patients switch to a "sick day" or "fasting" profile that delivers 50-80% of their normal basal rate.
  • Closed-loop settings: For users of MiniMed 780G with SmartGuard, you may need to turn off Auto Mode or set a higher glucose target (e.g., 120 mg/dL instead of 100 mg/dL) to reduce the risk of overcorrection during fasting. Review your CareLink reports to see how Auto Mode behaves during periods of low insulin demand.
  • Alarm thresholds: Some patients lower their hypoglycemia alarm threshold to 70 mg/dL in the days before a procedure to catch lows earlier. CareLink can show you if false alarms are a problem and whether the threshold adjustment would be beneficial.

    Checking Connectivity and Battery Life

    Nothing causes more anxiety than a dead pump battery or a failed upload on the morning of a procedure. Use CareLink to check the battery history of both your pump and transmitter. Many CGM transmitters have a life of about 7-12 months. If your transmitter is nearing its end, replace it before the procedure. Also, verify that you have the correct charging cable and a backup battery for your pump. The last thing you need is to be rushed to the operating room with a pump showing a low battery alert.

    Creating a Pre-Procedure Checklist

    To make sure nothing slips through the cracks, create a printed checklist that includes:

    1. Upload data to CareLink 14 days and 3 days before the procedure.
    2. Email reports to provider at least 1 week before.
    3. Confirm provider has looked at the data and given feedback.
    4. Adjust pump settings as instructed (temporary basal, alarm thresholds).
    5. Pack spare supplies: extra infusion set, reservoir, sensor, transmitter, batteries, glucose meter, and fast-acting glucose.
    6. Write a list of current medications, insulin types, and device serial numbers.
    7. Discuss with the anesthesia team whether the pump can remain attached during surgery (often it can, but they need to be aware).

    Keep this checklist accessible on your phone or printed in your procedure bag.

    Common Pitfalls and How to Avoid Them

    Pitfall: Waiting Until the Last Minute

    Many patients forget to upload data until the night before the procedure. By then, the provider may not have time to review it and respond. Solution: Set a calendar reminder for two weeks before your procedure to start reviewing your CareLink data. A second reminder three days before ensures you can handle any issues.

    Pitfall: Ignoring Nighttime Glucose Patterns

    Because most procedures require fasting after midnight, nighttime glucose management is crucial. CareLink reports can show nocturnal lows or highs that you might otherwise miss. If you see patterns, address them with your provider. Some patients benefit from a reduced overnight basal or a bedtime snack adjustment.

    Pitfall: Forgetting to Share with All Care Team Members

    Your endocrinologist may receive the data, but your surgeon and anesthesiologist may not. Solution: Use CareLink's sharing feature to send a summary report to each provider’s office directly. Alternatively, ask your endocrinologist to forward the relevant insights to the surgical team. A study published in the Journal of Diabetes Science and Technology highlighted that perioperative glucose management improves when all team members have access to CGM data—read more in this journal article.

    Preparing for a diabetes-related medical procedure no longer has to be a guessing game. CareLink gives you and your healthcare team the data you need to make precise adjustments, reduce risks, and promote a smooth recovery. By uploading data early, analyzing patterns, and sharing reports, you transform yourself from a passive patient into an active participant in your care.

    Remember: good preparation is a team effort. Use CareLink to open a conversation with your providers about glucose targets during fasting, insulin adjustments before sedation, and what to do if a device alarm goes off in the operating room. With the right data in hand, you can approach any procedure with confidence.

    For more detailed guidance on using CareLink, refer to the official Medtronic CareLink support page or consult your diabetes educator. Your health is worth the preparation.