Background & Health Considerations
"Lot 8" Background Information
Please know that Medtronic voluntarily initiated this recall - it was not triggered by a patient injury report. Medtronic received a report that an infusion set did not prime properly and our internal testing revealed that this was a result of clogged vents due to a change in the manufacturing process. Venting is necessary to equalize air pressure in the reservoir compartment with the surrounding atmosphere. Clogged vents could potentially cause too much or too little insulin to be delivered.
The manufacturing process was corrected and Medtronic is instructing patients to stop using "Lot 8" Quick-set infusion sets. Last week, Medtronic sent more than one million infusion sets to customers to ensure therapy continuation. The company is also working closely with distributor partners to provide infusion sets to everyone who needs them.
Blood Glucose Variability and Clogged Vents
Although patients may wonder if their past blood sugar variability is a result of clogged vents, our internal testing shows that the possibility for insulin over or under delivery is limited to the following two scenarios:
Scenario 1 - Over-Delivery of Insulin
For a significant hypoglycemic event to occur as a result of clogged vents, a rapid change in air pressure would be necessary. For example, when taking off in an airplane or quickly driving up a mountain, air pressure could build up inside the reservoir compartment and potentially cause over-delivery of insulin. This could result in a severe hypoglycemic event, which may require immediate action or assistance.
Since our testing shows that this occurs only with a rapid increase in altitude, this severe low blood sugar event is different than the typical low blood sugars that many people experience as part of their routine diabetes management.
Scenario 2 - Non-Delivery of Insulin
During priming, clogged vents may prevent the reservoir compartment from equalizing air pressure. As a result, the insulin pump may appear to be properly primed when it is not. Once the infusion set is inserted, this could lead to a period of non-delivery of insulin, which can potentially result in a hyperglycemic event following an infusion set change.
Since this occurs closely following an infusion set change, it may be different than the typical height blood sugars that many people experience as part of their routine diabetes management.
Therapy Considerations
Please review this information regarding therapy considerations associated with the "Lot 8" Quick-set infusion set recall:
"Lot 8" Quick-set infusion sets are the only infusion sets affected by this recall. If you do not have replacement Quick-set infusion sets, you can use any other Medtronic infusion sets you have been trained on and have available. These include Quick-sets other than "Lot 8," Silhouette infusion sets, Sof-set QR/Sof-set Ultimate QR infusion sets, Sure-T infusion sets and Polyfin infusion sets for use with MiniMed Paradigm insulin pumps. Any therapy adjustments, including the use of a different infusion set, should be made in consultation with your healthcare provider.
If circumstances occur where you do not have an alternative infusion set available, one option is to revert to the back-up injection plan established with your doctor. Please be aware of the following risks associated with continued use of "Lot 8" Quick-set infusion sets:
Risks Associated with Using "Lot 8" Quick-set Infusion Sets
Too Much Insulin Can be Delivered
- Changes in air pressure could cause too much insulin to be delivered when using an infusion set that does not vent properly.
- A rapid change in air pressure may cause a significant over delivery of insulin that may not be detected until after it has occurred.
- Examples where an increase in altitude can change air pressure include when an airplane is taking off, and when traveling from sea level to a higher elevation, such as driving up a mountain.
Any sign or symptom of hypoglycemia requires immediate attention and treatment.
Too Little Insulin Can be Delivered
- Even at stable altitude or stable air pressure, insulin delivery can be interrupted when using an infusion set that does not vent properly.
- The priming process builds up air pressure in the reservoir compartment and makes the insulin pump appear to be working properly when it is not.
- As always with insulin pump therapy, any interruption in insulin delivery would be detected through frequent blood glucose monitoring.