Insulin Distribution in Human Adipose Tissue via a Novel Insulin Infusion Catheter

Continuous subcutaneous insulin infusion (CSII) is a widely used treatment for diabetes patients. Insulin infusion sets (CSII-catheters) are continuously optimized regarding size, handling and safety, but recurring dysfunction (kinking or occlusion), due to different user situations, behavior or chain of events, demand new ways to improve the functionality and safety in patients experiencing these issues. A novel CSII-catheter design (Lantern) features additional lateral perforations, which guarantee functionality even in case of kinking or occlusion. This study aimed to compare functionality, insulin distribution, and failure rate of Lantern and standard catheters using excised human adipose tissue samples. Novel Lantern CSII-catheters (open and artificially occluded) and commercially available standard CSII-catheters were inserted into adipose tissue samples. A mixture of insulin and contrast agent was infused as single bolus (7 IU) with an insulin infusion pump at highest flow rate (1 IU/s). Microtomography images and surface-to-volume ratios were used to assess insulin distribution and depot volume indicating the functionality of CSII-catheters. Failure rate was measured by flow-stop alerts of the pump. We found no difference in the volume of insulin depots compared with the nominal volume of 70 mu L. Surface-to-volume ratios showed no significant difference among CSII-catheters. None of the catheters triggered any flow-stop alarm. The novel Lantern CSII-catheter design achieved similar insulin distribution as commercially available CSII-catheters. Moreover, functionality of Lantern CSII-catheters was guaranteed during occlusion, which is an improvement compared with standard CSII-catheters. We conclude that the novel CSII-catheter design has the potential to provide a valuable contribution to patient well-being and safety.