Hyperglycemia, hypoglycemia, and glycemic complexity are associated with worse outcomes after surgery.
OBJECTIVE
The purpose of this study was to determine if glycemic complexity, along with hypoglycemia and hyperglycemia, was associated with worse outcomes after cardiac surgery.


METHODS
We conducted a retrospective analysis of 970 patients who had insulin infusions designed to keep blood glucose levels between 80 and 110 mg/dL. Glycemic complexity was calculated using jackknifed approximate entropy. Logistic regression was used to adjust for confounders.


RESULTS
A total of 495 patients (51%) developed complications, and 32 patients (3.3%) died. Along with older age, comorbidities, and complicated surgeries, any hypoglycemia (glucose<71 mg/dL) and the number of glucose values greater than 140 mg/dL were independent predictors of complications. Increased risk of mortality, after adjusting for other risk factors, was associated with older age, longer perfusion time, receiving intraoperative transfusions, and greater jackknifed approximate entropy of the glucose time series.


CONCLUSIONS
We found that hypoglycemia (glucose<71 mg/dL) and hyperglycemia (glucose>140 mg/dL) were associated with increased risk of complications, whereas greater complexity of the glucose time series was associated with mortality.
Departments of Anesthesiology and Internal Medicine, Mercy St Vincent Medical Center, Toledo, OH; Department of Anesthesiology, University of Michigan, Ann Arbor, MI. Electronic address: engorenm@med.umich.edu.
Milo
M
Engoren
Department of Cardiovascular and Thoracic Surgery, University of Toledo, Toledo, OH.
Thomas A
TA
Schwann
Department of Internal Medicine and Outcomes Research Unit, American University of Beirut, Beirut, Lebanon.
Robert H
RH
Habib
D000328:Adult; D000367:Age Factors; D000368:Aged; D001786:Blood Glucose / Q000187:drug effects* / Q000378:metabolism; D006348:Cardiac Surgical Procedures / Q000009:adverse effects / Q000401:mortality*; D015897:Comorbidity; D016638:Critical Illness; D019277:Entropy; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000150:complications*; D007003:Hypoglycemia / Q000097:blood / Q000150:complications*; D007004:Hypoglycemic Agents / Q000008:administration & dosage*; D007328:Insulin / Q000008:administration & dosage*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome
D001786:Blood Glucose; D007004:Hypoglycemic Agents; D007328:Insulin
Diabetes mellitus; Outcomes