What is the management of intraoperative hyperglycemia?

From the Guidelines

Intraoperative hyperglycemia should be managed by maintaining blood glucose levels between 100-180 mg/dL.

Management Strategies

• A preoperative risk assessment should be performed for people with diabetes who are at high risk for ischemic heart disease and those with autonomic neuropathy or renal failure 1.
• The target range for blood glucose in the perioperative period should be 100-180 mg/dL (5.6-10.0 mmol/L) within 4 h of the surgery 1.
• Metformin should be held on the day of surgery, and SGLT2 inhibitors must be discontinued 3-4 days before surgery 1.
• Oral glucose-lowering agents should be held the morning of surgery or procedure, and basal insulin should be given at half of the NPH dose or 75-80% doses of long-acting analog or insulin pump basal insulin based on the type of diabetes and clinical judgment 1.
• Blood glucose should be monitored at least every 2-4 h while the individual takes nothing by mouth, and short- or rapid-acting insulin should be dosed as needed 1.
• Basal-bolus insulin coverage has been associated with improved glycemic outcomes and lower rates of perioperative complications compared with reactive, correction-only short- or rapid-acting insulin coverage alone with no basal insulin dosing 1.

Glycemic Targets

• Stricter glycemic targets tighter than 80-180 mg/dL (4.4-10.0 mmol/L) did not improve outcomes and were associated with more hypoglycemia 1.
• Moderate control of glycaemia (< 1.8 g/L or 10 mmol/L) decreased the number of hypoglycaemic episodes compared to strict control (0.8-1.2 g/L or 4.4-6.6 mmol/L) without any differences in morbidity/mortality in cardiac surgery 1.
• Blood glucose levels less than 150 mg/dL appear to be beneficial, and continuous intravenous insulin to achieve and maintain an early postoperative blood glucose concentration less than or equal to 180 mg/dL while avoiding hypoglycemia is indicated to reduce the incidence of adverse events, including deep sternal wound infection, after CABG 1.

From the Research

Management of Intraoperative Hyperglycemia

The management of intraoperative hyperglycemia is crucial to prevent postoperative complications. Several studies have investigated the optimal strategies for managing hyperglycemia during surgery.

• Intraoperative blood glucose management is associated with postoperative blood glucose levels, and adequate management can help prevent postoperative hyperglycemia 2.
• The optimal glycemic threshold for initiating insulin therapy is unknown, but starting insulin at a glucose threshold of 140 mg/dL may be associated with lower postoperative glucose levels and fewer incidences of postoperative hyperglycemia 2.
• Hyperglycemia is associated with increased mortality and morbidity in critically ill patients, and the treatment of hyperglycemia with insulin infusions has not provided consistent benefits 3.
• Patients with diabetes mellitus require more intensive perioperative glucose management, and the use of oral hypoglycemic agents should be carefully managed before surgery 3.
• The use of novel audiovisual monitors, such as AlertWatch, can modify intraoperative glycemic management behaviors and increase the initiation of insulin treatment for hyperglycemia 4.

Strategies for Managing Intraoperative Hyperglycemia

Several strategies can be employed to manage intraoperative hyperglycemia, including:

• Screening at-risk patients for hyperglycemia before surgery 5.
• Using preoperative oral hypoglycemics and home insulin to manage hyperglycemia 5.
• Selecting appropriate anesthetic types and medications to minimize the risk of hyperglycemia 5.
• Monitoring blood glucose levels during surgery and initiating insulin therapy as needed 2.
• Avoiding hypoglycemia and recognizing the risk of increased glucose variability 3.

Current Guidelines and Controversies

Current guidelines for perioperative glucose management are varied, but most suggest that tight glucose control may not be beneficial, while mild hyperglycemia appears to be well-tolerated 3, 6.

• The optimal glycemic targets for surgical patients are still a subject of debate, and more research is needed to determine the best approach to managing hyperglycemia during surgery 6.
• A sensible approach to managing hyperglycemia in the surgical population includes preoperative recognition of diabetes mellitus and risks for inpatient hyperglycemia, judicious control of glycemia during the pre-, intra-, and postoperative time periods, and avoidance of hypoglycemia 6.