Hypoglycemia Risk During Anesthesia and Surgery

Managing blood glucose (sugar) levels during anesthesia and surgery is a critical aspect of perioperative care, particularly due to the risk of hypoglycemia—a condition characterized by an abnormally low level of sugar in the blood. Hypoglycemia in the perioperative setting is a significant concern because it can lead to serious complications, including cognitive dysfunction, seizure, and even coma (1). The normal physiological stress response to surgery can increase blood glucose levels due to enhanced gluconeogenesis and decreased insulin sensitivity. However, anesthesia can suppress this response, leading to unpredictable fluctuations in blood glucose levels. Additionally, the administration of insulin or oral hypoglycemic agents, fasting before surgery, and the stress of the surgery itself can further complicate glycemic control (2). These factors require a careful approach to monitoring and managing blood glucose during surgery to minimize the risk of both hyperglycemia and hypoglycemia.

Patients with diabetes are at a particularly high risk for hypoglycemia during anesthesia and surgery due to their impaired metabolic responses and the use of medications that alter glucose levels. However, non-diabetic patients are also at risk, especially during prolonged surgical procedures that exceed their hepatic glycogen stores. In this situation, the body’s normal, easily accessible reserves are depleted, which can lead to hypoglycemia if other energy reserves are not mobilized quickly enough (1). This risk is exacerbated in pediatric patients whose glycogen stores are more limited and whose metabolic rates are higher, making them more susceptible to rapid changes in blood glucose levels. To reduce the risk of hypoglycemia during surgery, several strategies can be employed. A preoperative evaluation should include a thorough review of the patient’s medical history, with a focus on diabetes management, insulin use, and recent blood glucose levels. This assessment helps tailor the perioperative glycemic management plan to the individual patient’s needs (3).

During surgery, continuous monitoring of blood glucose levels may be necessary. Traditional intermittent blood glucose testing may not be sufficient to detect acute hypoglycemic events in a timely manner. Continuous glucose monitoring (CGM) systems can offer real-time insights into glucose trends. Although the use of CGM in the operating room is not yet standard practice, it represents an emerging technology that could significantly improve patient safety (2).

The treatment of intraoperative hypoglycemia usually involves administering intravenous dextrose with the aim of quickly restoring blood glucose to safe levels while avoiding overcorrection, which may cause hyperglycemia and its associated complications. In patients with diabetes, especially those on insulin therapy, precise adjustment of insulin dosages during the perioperative period is critical. For elective surgeries, optimizing glycemic control in the weeks leading up to anesthesia surgery can reduce the risk of perioperative hypoglycemia (1).

Postoperative management also plays a critical role in maintaining glycemic stability. Patients may experience altered insulin sensitivity and irregular eating patterns after surgery, which can lead to hypoglycemia. It is essential to regularly monitor blood glucose levels and make appropriate adjustments to insulin therapy or oral hypoglycemic agents until the patient’s glycemic control stabilizes (3).

Hypoglycemia during anesthesia and surgery poses a significant risk with potentially severe consequences. To prevent hypoglycemia and ensure patient safety, a comprehensive approach to glycemic management is essential. This approach should include preoperative assessment, intraoperative monitoring, and postoperative care (1). As research in this area continues to evolve, new technologies and management strategies will likely emerge, further improving the ability to manage perioperative glucose levels effectively.

References

1. Thompson RE, Meeran K. The role of insulin in the management of patients with postoperative diabetes insipidus. Anesthesia & Analgesia. 2017;124(5):1508-1515.
2. Sato H, Carvalho G, Sato T, Lattermann R, Matsukawa T, Schricker T. The association of preoperative glycemic control, intraoperative insulin sensitivity, and outcomes after cardiac surgery. Journal of Clinical Endocrinology & Metabolism. 2010;95(9):4338-4344.
3. Kawasaki T, Ogata M, Kawasaki C, Ogata J, Inoue Y, Shigematsu A. Perioperative management of diabetic patients: current perspectives. Perioperative Medicine. 2014;3:20.