Your pump will declare an occlusion alarm when it detects a blockage preventing insulin delivery. It will alarm and stop insulin delivery, until you acknowledge the alarm by pressing “OK” and ”Resume Insulin.” You may see either alarm 2A or 26A on your pump screen, as shown below; in both cases, insulin delivery is stopped and there are a few steps you should take to identify and fix the cause of the alarm so you can resume delivery.
TROUBLESHOOTING STEPS
When you receive Occlusion Alarm (2A), the pump instructs you to check the cartridge, tubing and site. These steps will help you figure out where the occlusion is occurring. While most occur at the infusion site on the body, it is possible for an occlusion to occur in the tubing or the pump cartridge.
Before beginning any of the troubleshooting steps below, be sure to disconnect your tubing from your infusion site first. If you have already resumed insulin, stop insulin and disconnect before troubleshooting.
- Tighten the t:lock connection between your infusion set tubing and your cartridge tubing by twisting it clockwise.
2. Check for visible air bubbles in the tubing. If you see any, unlock your pump screen and go to Options> Load -> Fill Tubing, and Tap “Fill” (not “New”) when prompted. Important: Be sure you are still disconnected from your infusion site before starting the tubing fill to prevent the unintended delivery of insulin.
3. When there are no visible air bubbles in your tubing, hold your tubing so that the connector needle is pointed down, and deliver a 5-unit bolus into the air. Note that this will affect the IOB displayed on your pump. If you are using Control-IQ technology, please note that pump may not increase your basal rate or deliver an automatic correction bolus for up to 5 hours due to this increase in displayed IOB. Please take this into account when making diabetes management decisions.
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- If the Occlusion Alarm did not recur during this bolus, the occlusion is likely at the infusion site. Remove the infusion set and inspect the cannula for any kinks or bends by gently wiggling the tip of the cannula. Also inspect the site on your body for redness, bumps, and leaking of insulin. Any visible damage to the cannula or inflammation at the site is most likely the cause of the occlusion. Insert a new infusion set in a new location and resume normal delivery. Review proper insertion technique for your infusion set.
This is what a Bent Cannula – a common cause for occlusions – may look like.
If the occlusion alarm did recur, the occlusion is likely in either the tubing or the cartridge itself. To determine which, continue with the next step.
4. The next step is to test the cartridge and tubing. First, disconnect tubing from the t:lock connection to the cartridge, hold the connection so it’s pointing down, and deliver another 5-unit bolus. Note that this will affect the IOB displayed on your pump. If you are using Control-IQ technology, please note that pump may not increase your basal rate or deliver an automatic correction bolus for up to 5 hours due to this increase in displayed IOB. Please take this into account when making management decisions.
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- If the Occlusion Alarm did not recur during this bolus, the occlusion is likely in the tubing. Change your infusion set and tubing and resume normal delivery.
- If the Occlusion Alarm did recur during the second bolus, the occlusion is likely in the cartridge. Install a new cartridge and resume normal delivery. Please pay particular attention to the air removal step in filling the cartridge. For step-by-step instructions on filling and loading a cartridge, please click here.
If you are also experiencing high glucose related to an occlusion, please consult the Glucose Troubleshooting guide.
TIPS TO PREVENT OCCLUSIONS
- Do not add insulin to the current cartridge.
- Do not reuse any insulin from old cartridges.
- Use room-temperature insulin when filling the cartridge.
- Fill cartridge with minimum of 95-120 units and no more than 300 units
- Change the cartridge and load pump according to the instructions here.
- Use approved, U-100 insulin.
- Choose a site free of scar tissue, surgical scars, tattoos and stretch marks (see recommended sites highlighted in green below).
- Practice good site rotation—below is an example of rotation patterns around the abdomen. Using the same area may cause scarring or lumps, which will affect insulin absorption.
- Wear your pump in a case, if possible, to help protect the pump and cartridge, and to improve ventilation surrounding the air vents.
If you follow these troubleshooting steps and tips but are still experiencing occlusions, please contact Tandem’s Customer Technical Support.
