Abstract:

Objective To observe the changes of perioperative insulin resistance during conventional coronary artery bypass grafting (CCABG) in patients with coronary atherosclerotic heart disease and different status of glucose metabolism. Methods Sixty patients with coronary atherosclerotic heart disease undergoing CCABG were divided into normal fasting plasma glucose group (normal control goup, n=20), fasting plasma glucose impairment group (n=20) and diabetes mellitus group (n=20) according to status of glucose metabolism before operation. Blood samples were taken from each group at different perioperative time points (before surgery, immediately after anesthesia, 5 min after the beginning of cardiopulmonary bypass, 10 min after rewarming, 5 min after protamine neutralization, 2 h after cardiopulmonary bypass, the third day after surgery and the seventh day surgery), the levels of fasting plasma glucose and fasting insulin were detected, and homeostatic model assessment of insulin resistance (HOMA-IR) was calculated. Results HOMA-IR of fasting plasma glucose impairment group and diabetes mellitus group was significantly higher than that of normal control group before surgery (P<0.05). Fasting plasma glucose levels and HOMA-IR of time points from 5 min after the beginning of cardiopulmonary bypass to the seventh day after surgery were significantly higher than those before surgery in normal control group and fasting plasma glucose impairment group (P<0.05). Fasting plasma glucose levels and HOMA-IR 5 min after the beginning of cardiopulmonary bypass were significantly higher than those before surgery in diabetes mellitus group (P<0.05), while there was no significant difference between fasting plasma glucose level of the seventh day after surgery and that before surgery and between HOMA-IR of the third day after surgery and the seventh day after surgery and that before surgery in diabetes mellitus group (P>0.05). Conclusion Fasting plasma glucose and insulin resistance increase during CCABG in patients with coronary artery disease, and the information of status of glucose metabolism before surgery may help to manage glucose metabolism disorder and improve insulin resistance.

Key words: glucose metabolism, insulin resistance, conventional coronary artery bypass grafting, coronary atherosclerotic heart disease