Insulin Pump Management for MRI Procedures

Introduction to Guidelines

• The British Journal of Anaesthesia guidelines (2016) recommend that for CT/MRI procedures, the pump and metal infusion set must be removed to prevent electromagnetic field interference and potential pump malfunction 1
• The Lancet Diabetes and Endocrinology (2021) reinforces that pumps must be removed for certain radiological procedures including MRI, emphasizing the importance of safety protocols 2, 3

Critical Safety Considerations

• The electromagnetic fields generated during MRI can cause insulin pump malfunction or failure, leading to unpredictable insulin delivery and potential heating of metal components in the infusion set 1, 4, 7
• Unpredictable insulin delivery (either excessive or interrupted) can occur due to MRI-related interference, posing a significant risk to patient safety 4

Management Protocol for MRI Procedures

Before MRI

• Start intravenous insulin infusion at least 30 minutes before disconnecting the pump, initially at the patient's programmed hourly basal rate, to prevent rapid hyperglycemia and ketosis 4, 5, 6, 7, 8
• Monitor blood glucose hourly during the transition to ensure adequate glucose control 7, 8

During MRI

• The pump remains outside the MRI room entirely to prevent interference and ensure patient safety 1, 2, 3
• Continue IV insulin infusion, adjusting based on blood glucose monitoring to maintain optimal glucose levels 5, 8

After MRI

• Reconnect the pump and run it alongside IV insulin for 2 hours to re-establish a subcutaneous insulin depot, ensuring a smooth transition back to normal insulin delivery 4, 5, 7, 8
• Monitor blood glucose hourly during this transition period to prevent hyperglycemia or hypoglycemia 7, 8

Important Caveats

• For emergency MRI situations where 30-minute overlap isn't feasible, start IV insulin immediately upon pump removal without delay to prevent diabetic ketoacidosis 5, 7, 8
• Continuous glucose monitors (CGMs) should also be removed for MRI, unless explicitly verified as safe by the manufacturer, to prevent potential interference or damage 10