The Tandem t:slim X2
Safety Reminder: When preventing DKA while using a hybrid closed loop pump
- Place the pump in manual mode before giving insulin by pen or syringe.
- Keep the pump in manual mode for at least 4 hours after the last injection of insulin by pen or syringe.
- After resuming automated insulin delivery, check that the desired glucose target is set.
- Colour touch screen
- Dexcom G6 CGM enabled
- Rechargable battery
- Tubed proprietary infusion sets
- Upgrades are done via software downloads after learning module completions.
- Basal IQ, the feature in older models, only reduces basal insulin but also allows for individualization of glucose targets e.g. in pregnancy. Tandem provides loaners for clients on Control IQ currently wishing to transfer to Basal IQ during their pregnancy.
- Control-IQ is in the newest upgrade. It adjusts insulin delivery to help prevent highs (automated partial corrections and increased basal insulin) and lows (temp basal suspensions), while requiring the user to manually bolus for meals. Individualization of glucose targets is not an option. The algorithm uses a patient's programmed basal rates, and correction factors (ISF) and potentially other factors to make automated dose adjustments. Carbohydrate counting and food boluses are still required. When Control IQ is active, a patient can adjust basal rates, ISF, carb ratios but not insulin duration, and not glucose targets.
- Consideration: If A1c prior to the start of using a hybrid closed loop (HCL) could drop quickly by more than 2% over 3 months (particularly for those with A1c in double digits), consider discussions with the specialist physican and patient about higher temporary glucose targets. Rapid A1c improvements have been associated with changes in retinopathy and rarely, painful treatment induced neuropathy of diabetes (TIND) or insulin edema.
How Control IQ Works
- SIMULATOR or VIRTUAL PUMP: Tandem t:simulator app for iPhone & Android
- MENU MAP - Tandem 2021
- User Manuals and Quick Reference Guides
- Patient education: Tandem FAQs and Tandem Guide for Successful Pumping
- Personal PIN over-ride is 314159
- CARES- Calculate, Adjust, Revert, Educate, Sensor
- Tandem Health Care professionals Page
- See below for notes and FYI for dose adjustments
- Analyzing Glooko Reports using Control IQ - 2022-06
- General Glooko Reports (not Tandem specific) - Video
- Glooko Legend (icons) eg. for set changes etc
- Tandem specific Glooko tips
- Summary Tab in Glooko:
Start here for AGP, TIR, time CGM active, insulin summary (basal bolus split etc), amount of time over riding pump, % time CIQ active, % time sleep activity is used. Average suspensions by day and more.
- Graphs Tab > Overview:
View about a week's worth of data. Hover over a single day to get more info. To see CIQ data, click Graphs tab > Overview > Click on one day to open a full-page single-day report. Click here for sample image. View day by day. Change the date range if needed.
Graphs Tab > Overlay:To pick weekends, vs weekdays or other days,
Graphs Tab > Calendar: To view over a period of time.
- Insights Tab: To view site changes. Shows CGM graph before and after each site change.
- Devices Tab: To view programmed basal profiles etc
- PDF only: WEEK VIEW: This report is only available when printing PDF reports. This PDF weekly report is a great overview to see CGM, boluses and CIQ action in one place.
- Personalize report selection for you as educator: Bottom right, under reports, you can select the types of reports you like regularly so when print to PDF, they are the default.
- Summary Tab in Glooko:
- Training Videos
- Specific Programming Videos (also see Tandem YouTube Channel)
- Navigating the Touch Screen
- Setting up Personal Profile - Options > My Pump > (choose profile)
- For each time segment, the following are required: basal rate, ISF, ICR.
- Loading and filling a cartridge
- Cartridge Fill Expectations
- Control IQ - Turning on
- Control IQ: Exercise Mode
- Control IQ: Sleep Mode
- Extend a Bolus
- Bolus Calculator
- Quick Bolus Button
- Set Temporary Basal Rate
- Stop and Resume Insulin
- Enter CGM Transmitter ID
- Home Screen Shortcut
- Turn Off Your Pump
- Unintended Touch Protection
- Understand the Wake Button Colored LEDs
- Cannula Fills
- t:90 set 6 mm cannula requires 0.3 units of insulin
- t:90 set 8 mm cannula requires 0.5 units of insulin
Indications, TDD, Weight & other FYI
- TDD and weight in Control IQ
- Indications for Control IQ are TDD 10-100 units per day and weight 25-140 kg. Patients beyond these indication levels have still used Control IQ; it is then an off-label usage. These are the maximum allowable entries into the system at initiation.
- Control-IQ uses these initial entries to enable the algorithm to start working right immediately without awaiting past data for the algorithm. However, as time passes, the algorithm uses actual delivered TDD based on a rolling 6 day average.
- However, if weight and/or TDD change dramatically and regularly (e.g. off-label DIP use or continual weight loss/gain), update the information as it can impact how the algorithm works.
- Max Basal Rate:
- If programmed basal rate is > 3u/hr, the system will deliver it if the CGM signal is active. However, for safety, if a CGM signal is lost for > 20 minutes the system reverts to 3u/hr as max even if their programmed rate is >3u/hr. To avoid this being an issue, suggest having the patient turn Control-IQ OFF during the two hour warm up on a new sensor every 10 days.
- For basal modulations and automated corrections in Control IQ, the algorithm requires the following.
- Programmed basal rates
- Programmed correction factor (ISF)
- The last 6 days of total daily insulin dose or the inputted total daily dose and weight at the start of using Control IQ. It’s recommended, but not required, to update these values on occasion. These should be updated to current values if resuming pump after having been off it.
- Current and predicted glucose reading 30 minutes out
- Glucose target (default, sleep or exercise mode)
- Insulin on board
- Bolus information
- Maximum bolus size is 25u. Over that, patients would need two boluses for a meal.
- Max extended bolus duration is 2 hours.
- Control IQ suggests manual meal boluse and manual corrections doses using the same calculations of the pump in manual mode.
- Duration of insulin action is set to 5 hours and cannot be changed in Control IQ
- These items below can be changed in Control IQ
- Basal rate and alternate basal profile
- Carb Ratio
- Insulin Sensitivity Factor e.g. Correction (may wish to make stronger if people are used to a shorter duration of insulin action e.g. from ISF of 3 to 2.5)
- The preset target from default (6.1 mmol/L) to sleep to activity
- To prevent getting Minimum Fill Notifications, fill reservoir/cartridge with about 50 units of insulin more than what is needed for tubing fill. Note: a minimum of A minimum of 10.2 units must be filled before you can stop the Fill Tubing step.
- Switching from another Automated Insulin Delivery Pump to Control IQ (CIQ)
- Suggestion: Use 40-45% of Total Daily Dose (TDD) for basal in CIQ
- For ISF use 90/TDD (this is more aggressive than standard 100/TDD)
- For ICR use 450/TDD (this is more aggressive than standard 500/TDD)
Control IQ Start Tips, Suggestions, Experiences
Starting Control IQ (CIQ) at the time of pump start requires a conversation with the patient and healthcare team. As a reminder, patients can self-train and start on their own; that needs to be kept in mind with the conversations. Safety is the priority, especially with switches from considerably longer acting injected basals (Tresiba) to CIQ. Some suggestions for discussion are below.
- When setting up CIQ, consider inputting only 75% of total daily insulin into the field requesting this data.
- Consider using Exercise Activity (higher target) if using CIQ at time of pump start.
- Depending on when Tresiba (degludec) or potentially other injected basal insulin was reduced or stopped, it may be safer to use one day (or more) of manual pump with a signifcant temp basal reduction before proceeding to CIQ using the Exercise Activity for the second day on pump.
- Prioritize your problem solving and change doses for actual hypoglycemia events that occur despite Control IQ suspending low.
- Frequent basal suspensions in the reports (red bars) do not necessarily indicate hypoglycemia or indicate a need for a change in therapy. Problem solve or change doses if the suspensions are for longer periods of time and/or with a regular pattern. Tandem indicates short suspensions are 5-30 minutes. Long suspensions are more than 30-45 minutes.
- Tandem suggests using 5-10 g or rapid acting carbohydrate to treat hypoglycemia and evaluate. Since basal insulin delivery had already been suspended for some period of time, the full carbohydrate treatment may not be needed.
- Frequent auto basal increases or hourly auto corrections in the Diasend reports do not necessarily indicate a need for change in therapy.
- Assess problem areas of high readings where the automated insulin delivery cannot address the hyperglycemia.
- The Tandem user guide reports the maximum insulin delivery rate is calculated using ISF (Insulin Sensitivity Factor or Correction Factor), estimated and recorded total daily insulin, and IOB (current insulin on board).
- Hyperglycemia occuring in repeated patterns may be addressed with basal rate changes or depending on the timing, ICR.
- Hyperglycemia that is frequent but sporadic in timing and non responsive may, after troubleshooting, be addressed with changes to ISF. Tandem Control IQ uses an insulin action time of 5 hours. Some patients have found they need a more aggressive ISF when in Control IQ.
- Patients may wish to set different basal profiles: A manual profile with usual (less aggressive) ISF when not using Control IQ; A profile for when control IQ is used on a usual day (may have a more aggressive ISF); A profile for when sick or menstruating which may have increased basal rates beyond the settings used for their usual Control IQ profile.
- Consider Exercise Activity (mode with higher target) 60-90 minutes prior exercise. How far in advance (and when to stop that higher target) will depend on the individual, the activity, the duration and past experience. Remember that if starting exercise with a higher glucose reading, this is not a protecting factor; Control IQ will still modulate basal rates and give partial correction doses to address this.
- If still experiencing lows with Exercise Activity, consider creating a new Personal Profile with decreased basal rates, less aggressive carb ratios and correction factors. Turn this “Exercise Profile” on prior to starting exercise. This may also be needed for exercise that is longer in duration (e.g.10k run) or extreme or extreme. As an example only, as this needs to be individualized:
- half the basal rate e.g. 1.0 u/hr to 0.5 u/hr
- double the carb in the ratio e.g. ICR of 10 to ICR of 20
- double the sensitivity of ISF e.g. ISF of 2 to ISF of 4
- If a user creates an alternate profile for an "extreme" activity and sets basal at 0.1 u/hr, the pump will still modulate insulin up (to an extent) or down from that starting point and still provide partial corrections based on the ISF in the profile.
- "Carb loading" may result in higher glucose readings and correction boluses even when Activity Exercise is set.
- Longer duration exercise of over an hour may also be managed by eating 15g CHO every half hour without bolusing. Caution though, as higher glucose readings will still trigger partial corrections. This emphasizes the importance of setting safe alternate ISF, basal rates and glucose target for exercise.
- Note: When setting alternate profiles for exercise (or other), new glucose targets are required to be programmed in. As long as Control IQ is on, the targets in these profiles will not be used.
- Turn off Exercise Activity and activate the usual personal profile 0 - 60 minutes after completing activity depending on glucose reading.
- If worried about delayed lows overnight, consider keeping Exercise Activity on overnight.
- Consider this Tandem webinar - Control-IQ Technology in Clinical Practice: Optimizing Control-IQ Management and T1D Outcomes (tandemdiabetes.com)
Sets & Misc
Kinked Canulas: If using an Autosoft 90 infusion set, sometimes the plastic cannula can lift closer to the top of the insertion needle. This can cause the cannula to kink on insertion. To prevent this from happening:
- Twist and lift the blue needle protector
- Lift the paper off the adhesion on the infusion set, then gently check that the cannula is well below the needle. (To avoid touching adhesive - and lifting- remove adhesive tab after the needle guard.)
- Ensure the tubing has not been placed in the notch of the inserter before it has been pulled (cocked) back. This can easily lift the infusion set off its
base and raise the plastic cannula higher so the needle does not have enough of a lead to insert the plastic cannula properly.
- Once the infusion set has been pulled back, then place the tubing in the notch.
- Check the needle and make sure the cannula is well behind the needle. Then inject by squeezing the two flat circular areas together
- Be sure to massage the white handle of the infusion set well before removing the needle. This ensures the adhesive is well stuck to the skin. Then remove the needle by pulling the white handle (not the outside part) straight out. The needle should be straight after removal.
- Tandem Diabetes Care Canada Website adn the Tandem Health Care Professionals site
"Office Hours" for Healthcare Professionals ONLY to connect with Tandem Trainers are below:
Monday’s 3pm – 7pm ET hosted by Teri Currie RN, CDE
Wednesday’s 12pm – 4pm ET hosted by Jessica Eichler RD, CDE
Thursday’s 12pm – 4pm ET hosted by Donna McGlennon RN, CDE
Thursday’s 10am – 2pm ET hosted by Jennifer Rene RN, CDE (FRENCH)
Friday’s 11am – 3pm ET hosted by Amanda Coschi RN, CDE