Perioperative Glucose Management in Diabetic Patients

Primary Management Strategy

The American College of Anaesthesiologists recommends administering IV glucose at 4 g/hour when continuous IV insulin is required to maintain target blood glucose of 5-10 mmol/L while preventing hypoglycemia 1, 2, 3
Insulin therapy, when needed, must always be accompanied by IV glucose administration to avoid hypoglycemia while maintaining glycemic control 1, 2, 3

The American College of Anaesthesiologists recommends using ultra-rapid short-acting insulin analogues via continuous IV infusion, with a typical starting rate of 1-2 units/hour, adjusted based on frequent glucose monitoring 1, 2, 3, 4
Never administer IV insulin without concurrent IV glucose, as this is a critical safety measure 1, 2, 3

Measure blood glucose every 1-2 hours during stable periods, and increase to hourly monitoring after each insulin rate adjustment 1, 2, 3, 4, 5
Monitor potassium every 4 hours during insulin therapy, targeting 4-4.5 mmol/L 4

Schedule diabetic patients first in the morning to minimize prolonged fasting, which increases perioperative glycemic instability 1, 2, 3, 4
Preoperative glucose infusion is NOT necessary if the patient is not receiving insulin 6

For patients NOT requiring insulin, non-insulin medications are held on the morning of surgery, and metformin is held from the evening before surgery 6
SGLT2 inhibitors must be discontinued 3-4 days before surgery to prevent euglycemic diabetic ketoacidosis 5

Never pursue glucose targets <100 mg/dL (5.5 mmol/L) perioperatively, as this increases hypoglycemia without benefit 5
Never administer IV insulin without concurrent glucose infusion, as this causes severe hypoglycemia 1, 2, 3

For Type 1 diabetic patients, insulin deficiency leads to ketoacidosis within hours, and continuous insulin replacement is mandatory at all times 6
When transitioning from IV to subcutaneous insulin, administer basal insulin 2-4 hours before stopping IV insulin to prevent rebound hyperglycemia and ketoacidosis 5
Glucocorticoids induce hyperglycemia in 56-86% of hospitalized patients, and require substantial increases in prandial and correction insulin 5

In hemodynamically stable surgical patients receiving pioglitazone who have normal cardiac function, no evidence of fluid overload, and satisfactory glycemic control, the medication should be continued on the day of anesthesia. 7

Patients with target‑range glycated hemoglobin (HbA1c) indicating good baseline glycemic control are appropriate candidates for peri‑operative continuation of pioglitazone. 7
Elective procedures in which oral intake is expected to resume early post‑operatively satisfy the conditions for maintaining pioglitazone through the peri‑operative period. 7
In the absence of heart failure (i.e., patients without clinical signs of volume overload or decompensation), pioglitazone may be safely continued. 7

Pioglitazone should be restarted with the first postoperative meal once oral intake is re‑established. 7
Prior to each postoperative dose (during the first 24–48 hours), clinicians should reassess the patient’s volume status to detect early fluid retention. 7

Close monitoring of volume status in the immediate postoperative period is advised, as surgical stress and intravenous fluids can reveal subclinical fluid retention associated with pioglitazone. 7