title: Acceleration of insulin pharmacodynamic profile by a novel insulin infusion site warming device.
abstract: OBJECTIVE
  Subcutaneously injected rapid-acting insulin analogs do not replicate physiologic insulin action due to delays in their onset and peak action resulting in postprandial glucose excursions. The InsuPatch (IP) is a novel insulin infusion site warming device developed to accelerate insulin action by increasing blood flow to the area of insulin absorption. Thirteen adolescents with type 1 diabetes (T1D, mean age 14 ± 4 yr) were enrolled in this study to investigate the effect of the IP on the pharmacodynamics and pharmacokinetics of a 0.2 unit/kg bolus dose of aspart insulin using the euglycemic clamp technique.
  
  
  METHODS
  Each subject underwent two euglycemic clamp procedures on separate occasions: one with IP and one without IP activation in random order.
  
  
  RESULTS
  When the insulin bolus was given with IP activation as compared to without IP activation, time to reach maximum insulin action (T(GIRmax)) and to reach 50% maximum action (T(50%GIRmax)) were 35 and 18 min earlier (125 ± 8 min vs. 90 ± 6 min, p = 0.002 and 58 ± 5 min. vs. 40 ± 3 min, p = 0.01, respectively), and the area under curve, AUC(GIR 0-90 min), reflecting early glucodynamic action, was significantly greater (p = 0.001). IP activation also accelerated the rise in plasma insulin levels after the bolus (p = 0.03) and resulted in a higher peak (p = 0.04) and greater overall increase (p = 0.02) in plasma insulin levels.
  
  
  CONCLUSIONS
  Our results show that insulin infusion site warming with IP activation accelerates the time action profile of aspart insulin which may be of benefit to current open-loop and future closed-loop insulin delivery in patients with T1D.
authors.affiliation: Division of Pediatric Endocrinology & Diabetes, Yale School of Medicine, New Haven, CT 06520, USA. Eda.Cengiz@yale.edu
authors.forename: Eda
authors.initials: E
authors.lastname: Cengiz
authors.forename: Stuart A
authors.initials: SA
authors.lastname: Weinzimer
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Sherr
authors.forename: Eileen
authors.initials: E
authors.lastname: Tichy
authors.forename: Melody
authors.initials: M
authors.lastname: Martin
authors.forename: Lori
authors.initials: L
authors.lastname: Carria
authors.forename: Amy
authors.initials: A
authors.lastname: Steffen
authors.forename: William V
authors.initials: WV
authors.lastname: Tamborlane
mesh_terms: D000042:Absorption; D000293:Adolescent; D001786:Blood Glucose / Q000032:analysis; D002648:Child; D018592:Cross-Over Studies; D003922:Diabetes Mellitus, Type 1 / Q000097:blood / Q000188:drug therapy*; D005260:Female; D015309:Glucose Clamp Technique; D006358:Hot Temperature; D006801:Humans; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use; D055104:Infusions, Subcutaneous; D061267:Insulin Aspart / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics / Q000627:therapeutic use; D007332:Insulin Infusion Systems; D008297:Male; D012039:Regional Blood Flow; D012881:Skin Temperature
chemical_list: D001786:Blood Glucose; D007004:Hypoglycemic Agents; D061267:Insulin Aspart