Development of remotely controlled implantable devices for programmed insulin infusion.

Area of Science:

• Biomedical Engineering
• Endocrinology
• Medical Devices

Background:

• Externally worn insulin pumps have shown efficacy in managing labile diabetes.
• Long-term therapeutic potential necessitates the development of implantable insulin delivery systems.
• Key requirements for implantable devices include small size, light weight, longevity, biocompatibility, reliability, safety, and external controllability.

Purpose of the Study:

• To develop and evaluate an implantable insulin infusion device for long-term diabetes therapy.
• To ensure the device is safe, reliable, and user-friendly for patients with labile diabetes.

Main Methods:

• Development of a compact (94 cm3, 180 g) implantable insulin pump with a 10 ml refillable reservoir.
• Utilized a roller pump driven by a stepping motor for insulin delivery, programmable for basal rates and prandial doses.
• Incorporated a telecontrol system for programming, monitoring, and safety checks, including over-dosing prevention mechanisms.
• Encapsulated all components in a titanium housing with an underpressure system to prevent insulin leakage.

Main Results:

• The implantable device has a reservoir requiring refills approximately every three weeks (at 100 units/ml insulin concentration).
• A lithium battery provides power for over one year.
• The device allows programming of 12 basal rates and 12 prandial doses, with automatic return to basal rate after one hour.
• Extensive testing in dogs and recent human implantation of research prototypes have been conducted.

Conclusions:

• The developed implantable insulin infusion device offers a promising solution for long-term, controlled insulin delivery in labile diabetics.
• The design emphasizes safety, with features to prevent overdosing and ensure biocompatibility and reliability.
• Further clinical evaluation is warranted to confirm the long-term efficacy and safety in a broader patient population.