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Real-Time Proxy-Control of Re-Parameterized Peripheral Signals using a Close-Loop Interface
Published on: May 8, 2021
Glucose control using a closed-loop device decreases inflammation after cardiovascular surgery without increasing
Takahiko Tamura1, Tomoaki Yatabe2, Tsutomu Namikawa3
1Department of Anesthesiology and Intensive Care Medicine, Kochi Medical School, Kohasu, Oko-cho, Nankoku, Kochi, 783-8505, Japan. tamura_t@kochi-u.ac.jp.
Insights
Closed-loop glucose control within 110-180 mg/dL significantly reduced inflammation markers after cardiovascular surgery. This approach offers a potential strategy to manage post-operative inflammation without increasing hypoglycemia risk.
Area of Science:
- Cardiovascular Surgery
- Intensive Care Medicine
- Metabolic Regulation
Background:
- Tight glucose control may mitigate inflammation post-cardiac surgery.
- The efficacy of a 110-180 mg/dL glucose target range for controlling inflammation remains uncertain.
Purpose of the Study:
- To investigate if a glucose target range of 110-180 mg/dL decreases inflammation following cardiovascular surgery.
- To compare the inflammatory response between closed-loop and conventional glucose control methods.
Main Methods:
- Retrospective study of 72 cardiovascular surgery patients.
- Two groups: closed-loop control (110-180 mg/dL) vs. conventional control (<200 mg/dL).
- Primary outcome: C-reactive protein (CRP) levels on postoperative days 1, 2, and 7.
Main Results:
- The closed-loop group exhibited significantly lower average glucose levels (169±24 vs. 201±36 mg/dL) and glucose variability (22±13 vs. 44±20 mg/dL).
- Significantly lower CRP levels were observed in the closed-loop group on postoperative days 2 (10.8±5.6 vs. 14.1±5.7 mg/dL) and 7 (4.6±2.5 vs. 7.3±4.0 mg/dL).
Conclusions:
- Glucose control using a closed-loop device within the 110-180 mg/dL range may reduce post-cardiovascular surgery inflammation.
- This method appears effective without elevating the risk of hypoglycemia.
Abstract:
Although tight glucose control might reduce inflammation after cardiac surgery, it remains unclear whether inflammation can be controlled by maintaining glucose levels within 110-180 mg/dL. We hypothesized that a glucose target range of 110-180 mg/dL decreases inflammation after cardiovascular surgery. This retrospective study included 72 cardiovascular surgery patients divided into two groups according to the glucose control approach. Patients allocated to the closed-loop group received closed-loop glucose control (target glucose levels at 110-180 mg/dL) from admission to the intensive care unit until 9 a.m. on postoperative day (POD) 1. Patients allocated to the conventional group received conventional glucose control using a sliding scale method to maintain blood glucose levels < 200 mg/dL. Primary outcomes were C-reactive protein (CRP) levels on PODs 1, 2, and 7. Data were reported as mean ± standard deviation. Comparisons were performed using the chi-squared test and unpaired t test, with p < 0.05 indicating statistical significance. The closed-loop group had significantly lower average glucose levels (169 ± 24 vs. 201 ± 36 mg/dL, p < 0.001) and standard deviation of glucose levels (22 ± 13 vs. 44 ± 20 mg/dL; p < 0.001). The CRP levels on PODs 2 and 7 were significantly lower in the closed-loop group than in the conventional group (10.8 ± 5.6 vs. 14.1 ± 5.7 mg/dL, p = 0.02; 4.6 ± 2.5 vs. 7.3 ± 4.0 mg/dL, p < 0.001; respectively). Our findings suggest that glucose control using a closed-loop device might decrease inflammation after cardiovascular surgery without increasing hypoglycemia risk.
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