title: Patient-specific insulin-resistance-guided infusion improves glycemic control in cardiac surgery.
abstract: BACKGROUND
  Maintenance of appropriate capillary blood glucose in cardiovascular surgery patients has been associated with improved outcomes, including lower mortality. Interpatient variability in insulin resistance can make management difficult, leading to unexpected episodes of hypoglycemia and hyperglycemia. To improve postoperative glucose control at our institution, a patient-specific insulin-resistance-guided (IRG) protocol was developed.
  
  
  METHODS
  Prospective data were gathered on 100 consecutive cardiovascular surgery patients managed with our standard insulin infusion protocol and 100 patients managed using the IRG protocol. Clinical characteristics and glycemic indices were analyzed for the two groups. Primary endpoints included (1) percentage of time spent in the target range, (2) number of hypoglycemic and hyperglycemic episodes, (3) time to achievement of target blood glucose, and (4) the total daily dose of insulin required.
  
  
  RESULTS
  The IRG protocol resulted in significant improvements, including increased percentage of time spent in the normoglycemic range (82.5% versus 65.8%, p < 0.001), reduced rate of hypoglycemic episodes (0.12 versus 0.99, p < 0.01), reduced rate of hyperglycemic episodes (capillary blood glucose >126 mg/dL: 4.8 versus 8.2, p < 0.01), and a reduced time to the first measurement in the target range. Total daily dose of insulin was mildly increased, but failed to reach statistical significance (92.48 versus 82.64 units, p = 0.32).
  
  
  CONCLUSIONS
  Use of the IRG protocol led to improved glycemic indices while reducing episodes of hypoglycemia in both diabetic and nondiabetic patients. The ability to adjust a patient's insulin dosing based upon factors related to their insulin resistance results in improved blood glucose control and safety in cardiovascular surgery patients.
authors.affiliation: Division of Cardiothoracic Surgery, Oregon Health and Science University, Portland, Oregon 97239, USA.
authors.forename: Kirk A
authors.initials: KA
authors.lastname: Caddell
authors.forename: Christopher B
authors.initials: CB
authors.lastname: Komanapalli
authors.forename: Matthew S
authors.initials: MS
authors.lastname: Slater
authors.forename: Daniel
authors.initials: D
authors.lastname: Hagg
authors.forename: Frederick A
authors.initials: FA
authors.lastname: Tibayan
authors.forename: Stephen
authors.initials: S
authors.lastname: Smith
authors.forename: Andrew
authors.initials: A
authors.lastname: Ahmann
authors.forename: Steven W
authors.initials: SW
authors.lastname: Guyton
authors.forename: Howard K
authors.initials: HK
authors.lastname: Song
mesh_terms: D001786:Blood Glucose / Q000378:metabolism*; D006348:Cardiac Surgical Procedures; D004305:Dose-Response Relationship, Drug; D005260:Female; D005500:Follow-Up Studies; D038321:Glycemic Index; D006331:Heart Diseases / Q000601:surgery; D006801:Humans; D007003:Hypoglycemia / Q000097:blood / Q000517:prevention & control*; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D007262:Infusions, Intravenous; D007328:Insulin / Q000008:administration & dosage*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D011446:Prospective Studies; D016896:Treatment Outcome
chemical_list: D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin