6.4 Management of hyperglycemia in hospitalized patients

Insulin therapy should be initiated for treatment of persistent hyperglycemia at a threshold >10.0 mmol/L (checked on two occasions).

Once insulin therapy is started, a target glucose range of 7.8-10.0 mmol/L is recommended for the majority of critically ill and non-critically ill patients.¹

Table 6.5 Insulin therapy in critical and noncritical setting¹

Insulin therapy¹

• Insulin therapy is preferred for treatment of hyperglycemia in all hospitalized individuals.
• In noncritical setting, scheduled insulin regimen is recommended.
• Use of sliding scale insulin regimen is strongly discouraged.
• Pre-mixed insulin is not preferred in hospitalized patients.
• If oral intake is poor, a safer procedure is to administer prandial insulin immediately after the person eats.

Glucose monitoring in hospital¹

• Those who are on oral feeding: bedside glucose monitoring before meals and 2 hours after meals.
• Those who are on NG tube/NPO: bedside glucose monitoring every 4-6 hours.
• In critical setting, who are on IV insulin: more frequent monitoring from every 30 minutes to 2 hours may be needed.

• Pre-operative assessment must be done in close consultation with the physician, surgeon and anesthetist.
• Metformin should be stopped 24 hours prior to or on the day of surgery.
• SGLT2 inhibitors must be discontinued 3-4 days before surgery.
• Withhold any other oral glucose lowering agents in the morning of surgery or procedure and give half of NPH dose or 75-80% doses of long acting analogue if scheduled in morning.
• The target blood glucose in perioperative period is 7.7-10.0 mmol/L.⁹
• In all major surgeries glucose-insulin infusion should be started. The unit of insulin to be added to 5 or 10% dextrose or dextrose saline needs to be individualized and adjusted as per the results of the glucometer readings.
• Blood glucose should be monitored 2 to 4 hourly. Glucose-insulin-potassium infusion may be considered according to situations. Best option I/V insulin syringe pump which can be practiced in long surgical procedure.
• During minor surgery glucose-insulin infusion may sometimes be required in uncontrolled diabetes, but not in stable state.

Table 6.6 Insulin dose adjustment prior and during surgery¹⁰

Post-operative care¹

• The glucose-insulin administration is continued (where required) till the person is able to take oral food.
• At this time, if the blood glucose is not under fair control, rapid acting insulin can be given in small doses (as correctional dose) subcutaneously.
• Once the person is back on his routine diet and is stable, he or she can be managed with the prior regimen to surgery.

6.4.3 Glucocorticoid therapy in hospitalized patients¹

• The prevalence of Glucocorticoid use in hospitalized patients can be as high as 10%.
• Those on morning steroid regimens have disproportionate hyperglycemia during the day, but frequently reach normal blood glucose overnight.
• In individuals with once or twice daily steroids, administration of NPH insulin is a standard approach. As NPH action peaks at 4-6 hours after administration, it is best to give concomitantly with steroid.
• For long acting glucocorticoids like Dexamethasone and multidose or continuous steroid use, long acting insulin required to control fasting blood glucose.
• Insulin dose should be adjusted with anticipated change in steroid dosing.

6.4.4 Glucose management in enteral and parenteral feeing¹¹

Enteral feeding

Enteral nutrition is started via nasogastric tube, or less frequently, percutaneous gastric tube. Diabetic specific formulas contain carbohydrates with monounsaturated fatty acids (up to 35 % of total calories), dietary fiber (10-15 g/L), and fructose. Low dose basal insulin in combination with supplemental regular insulin was shown to be effective in providing glycemic control in majority of patients receiving enteral feedings.

Parenteral feeding

Both subcutaneous and intravenous insulin have been shown to be effective in managing hyperglycemia in patients with TPN. In critically ill or hemodynamically compromised patients, treatment with intravenous continuous insulin infusion is preferred. Adding insulin to TPN mixture is clinically safe and effective in controlling hyperglycemia during TPN. Adding insulin at the ratio of 1 unit of insulin per 11 g of dextrose in persons with diabetes receiving TPN containing 150-300 g of carbohydrates per day is an effective initial step to prevent and reduce hyperglycemia.