Open Loop Insulin Delivery Device for the Control of Glycemia

摘要

Four routes of insulin administration were evaluated for suitability for use with implantable pumps. Subcutaneous (SQ), intraperitoneal (IP), inferior vena caval (IVC) and portal (PV) routes were studied sequentially in mongrels dogs. Good but not perfect control of glycemia was achieved in all routes. However during subcutaneous infusion, a trend toward hyperinsulinemia was noted. Subcutaneous delivery had a high complication rate. Venous (portal or caval) delivery was complication free when 80% glycerol was used to promote solubility. However, it appeared to cause sterile abcesses and adhesions when used for intraperitoneal infusion. Approximately 30 potential insulin infusates were evaluated in rotating vial studies and another 12 in rotating Infusaid TM pumps. Lack of precision and repeatability of current methodology made these results difficult to interpret. A bolus-accumulator equipped implantable pump was evaluated in bench tests and is currently undergoing in vivo study.