Chapter 5 - Use of intraperitoneal insulin delivery for artificial pancreas

Abstract

From the initial bedside in-hospital artificial pancreas (AP), the development of wearable ambulatory closed-loop systems for the therapy of type 1 diabetes has prioritized the mode of subcutaneous (SC) insulin delivery according to the widespread diffusion of pumps for continuous subcutaneous insulin infusion. Although these AP systems have shown their ability to reach a safe and efficient automated glucose control in basal free-life conditions for several months, they still need meal announcement by the patients for the calculation of insulin bolus at meal time and remain cumbersome due to the external glucose monitoring and insulin infusion devices. Intraperitoneal (IP) insulin infusion from implantable programmable pumps or through implanted abdominal ports has been limited in clinical use to cases of unreliable SC insulin absorption or highly variable glucose levels including severe hypoglycaemia. Nevertheless, IP insulin pharmacokinetics show quicker insulin action and lower basal insulin levels thanks to first portal distribution of absorbed insulin. IP insulin delivery has been explored in AP systems in combination with IV or SC glucose sensing and recently compared to SC insulin route. Whereas basal control is safe with minimal variability, post meal glucose excursions are reduced without meal announcement thanks to allowed higher insulin infusion rates without increased time in hypoglycaemia. Development of new models of implantable pumps with updated electronics, improved insulin stability, and redesigned catheters to prevent occlusions, ideally connected to IP glucose sensors, could lead to a fully automated and implanted artificial beta cell responding to unmet needs by current AP systems.