Is an automatic pump suspension feature safe for children with type 1 diabetes? An exploratory analysis with a closed-loop system

• Published in: Diabetes technology & therapeutics Vol. 11; no. 4; p. 207
• Main Authors: Cengiz, Eda, Swan, Karena L, Tamborlane, William V, Steil, Garry M, Steffen, Amy T, Weinzimer, Stuart A
• Format: Journal Article
• Language: English
• Published: United States 01.04.2009
• Subjects: Adolescent; Automation - standards; Blood Glucose - drug effects; Blood Glucose - metabolism; Diabetes Mellitus, Type 1 - blood; Diabetes Mellitus, Type 1 - drug therapy; Female; Glycated Hemoglobin - metabolism; Humans; Hypoglycemia - prevention & control; Insulin - administration & dosage; Insulin Infusion Systems - adverse effects; Insulin Infusion Systems - standards; Male; Safety
• ISSN: 1520-9156; 1557-8593
• DOI: 10.1089/dia.2008.0102

It has been proposed that the first step towards a closed-loop artificial pancreas might be to use a continuous glucose sensor to automatically suspend the basal insulin delivery based on projected low sensor glucose values. We reviewed our recent experience with an artificial pancreas system, utilizing a proportional-integrative-derivative (PID) algorithm, in 17 adolescents with type 1 diabetes (T1D) to assess the safety and efficacy of this maneuver. During 34 h of closed-loop automated insulin delivery, 18 pump suspensions > or =60 min (90 +/- 18 min) occurred in eight subjects. Sensor glucose levels fell from 159 +/- 42 mg/dL to a nadir of 72 +/- 13 mg/dL. Corresponding plasma glucose levels fell from 168 +/- 51 to 72 +/- 16 mg/dL, with values <60 mg/dL recorded in only four of the 18 events. These data suggest that automatic pump suspension using the PID algorithm may be an effective means to prevent hypoglycemia in youth with T1D.