Glucose Control by eMPC Algorithm in Peri- and Postoperative Period in Cardiac Surgery Patients

• Mean blood glucose
  
• percentage of time in target range
  

• Number of hypoglycaemic episodes
  

Context. Increased blood glucose levels frequently occur in critically ill patients and its normalization by intensive insulin treatment markedly improves clinical outcome.

Objective and Design: Randomized controlled trial to compare blood glucose control by the model predictive control algorithm with variable sampling rate (eMPC) with routine glucose management protocol (RMP) in peri- and postoperative period in cardiac surgery patients.

Setting: Department of Cardiac Surgery, University Hospital. Patients. 60 cardiac surgery patients. Interventions. Elective cardiac surgery and treatment with continuous insulin infusion to maintain euglycemia (target range 4.4 – 6.1 mmol/l). 30 patients were randomized for eMPC and 30 for RMP treatment. Blood glucose was measured in 1-4 hour intervals depending on request of each algorithm during surgery and post-operation period for 24 hours.

Main Outcome Measures. Mean blood glucose, percentage of time in target range. Results. Mean blood glucose was 6.15 ± 1.11 mmol/l in eMPC vs. 7.21 ± 1.08 mmol/l in RMP group (p<0.05); percentage of time in target range was 60.4 ± 22.8% for eMPC vs. 27.5 ± 16.2% for RMP group (p<0.05). No severe hypoglycemia (blood glucose bellow 2.9 mmol/l) was observed during the study. Average insulin infusion rate was 4.67 ± 3.34 in eMPC vs. 2.57 ± 1.66 IU/h in RMP (p<0.05), average sampling interval was 1.46 ± 0.31 vs. 2.10 ± 0.22 hours (p<0.05).

Conclusions. eMPC algorithm was more effective and comparably safe as compared to RMP in maintaining euglycemia in cardiac surgery patients.