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Diabetes at the RCH

Insulin pump line failure

  • Insulin pump line failure: blood glucose level (BGL) of 15 mmol/L or higher with ketones of 0.6 mmol/L or higher 

    High blood glucose + ketones = Not enough insulin in the body

    • Insulin pump therapy carries a higher risk for developing ketones compared to other insulin regimens because only rapid acting insulin only is used
    • Insulin pump users need to have access to rapid acting injected insulin at all times as an alternative way of giving insulin e.g. NovoRapid® Flexpen or Humalog® Kwikpen.
    • A ketone reading of 0.6mmol/L or higher is positive and if associated with BGL 15.0mmol/L or higher needs immediate treatment with an 'urgent dose' injected insulin (see below) via pen or syringe

    Step 1

    • Calculate 'urgent dose' by dividing your pump total daily dose (PTDD) of insulin by 6
    • Give this 'urgent dose' of Novorapid®/Humalog® via pen or syringe. Do not use the pump to correct the high glucose. 
    • Turn automode off i.e. SmartGuard (Medtronic), Control IQ (Tandem), automode (Ypso), Smart Adjust (Omnipod). This ensure that the pump will not auto adjust insulin whilst the insulin injection is working. 
    • Disconnect the pump from your body.
    • Enter the BGL into the pump, change the recommended bolus to the urgent dose just injected and deliver the insulin correction into the air.
      This will keep a record of the BGL and the injected insulin in the pump. Your injected insulin will be calculated in your active insulin/insulin on board.
    • Complete a full insulin reservoir, line and cannula change and reconnect your pump. It is ok for basal insulin to be running at this time (manual mode). 

    Urgent dose will change as PTDD changes. Please update this dose regularly.

    PTDD is accessed in you pump history or from your download report:

    • MEDTRONIC – History – Summary – 7 Days
    • T SLIM: Options – Pump History – Delivery Summary – 7 Day Average
    • Ypso CamAPS: CamAPS app - Main Menu and statistics or on your Glooko report
    • Omnipod - Can be viewed on Glooko 

    Step 2

    • Re-check BGL and ketones in 2 hours
      • If ketones are 0.6 mmol/L or higher and BGL is 15 mmol/L or higher, repeat step 1 (inject pen insulin using the 'urgent dose'), however a line change is not required. Unless you are confident with appropriate action, seek urgent medical advice. Continue close monitoring.
      • If ketones are 0.6 mmol/L or higher and BGL is 14.9 mmol/L or lower, enter your BGL and any carbohydrate consumed into the pump and give the calculated bolus. Turn automode back on. Continue close monitoring and seek medical attention if any concerns. 
      • If ketones are 0.5 mmol/L or lower, Bolus as usual through your insulin pump. Turn automode back on. 

    • Continue to re-check your BGL & Ketones two hourly until BGLs are less than 15mmol/L and ketones 0.5 mmol/L or lower. Remember that when you are back on your pump, ensure you turn automode back on.  

    You will not know your new line is working until the effect of your injected insulin has finished. Be aware – Every line change carries the risk of line failure.

    Updated January 2026

  • Seek urgent medical attention or call an ambulance by dialing 000 if: 

    • You have had 3 vomits or diarrhoea or continued stomach pains, especially if these pains are associated with high BGLs.

    • If at any stage, ketones are 3.0 mmol/L or higher, you should give an 'urgent dose' of rapid acting insulin as explained above and present to hospital for urgent medical assessment. This situation has a high risk of diabetic ketoacidosis (DKA) which is a medical emergency.  Remember signs of DKA include; vomiting, stomach pain, rapid breathing, drowsiness.

    • After following the above advice, ketone levels are increasing or remain 0.6 mmol/L or higher. 

    The Royal Children's Hospital (RCH) Sick day service phone number 9345 5522 ask for the 'Diabetes sick day call' 7am – 9pm Monday – Friday (for patients of the RCH).