Fluids, Electrolytes, Acid-Base Disorders, and Nutrition Support

Excessive insulin dose

ii.

Abrupt discontinuation of EN or PN without an adjustment in the insulin therapy (purported

to cause 62% of severe hypoglycemic events in the 2006 Van den Berghe trial of medical ICU

iii.

Decreasing steroid dose while on insulin therapy

iv.

Hepatic failure

Renal failure (half-life of insulin is prolonged, impaired renal gluconeogenesis in response to

hypoglycemia)

vi.

Advanced age

vii.

Inotropes, vasopressor agents, octreotide with insulin therapy

viii.

Sepsis

Transitioning from a continuous intravenous insulin infusion

Lack of a transition plan results in loss of glycemic control. Different methods have been described

in the literature, and the best approach depends on whether the patient is transitioning to an oral

2012;40:3251-76; ASPEN Adult Nutrition Support Core Curriculum 2012:580-602).

Once stable, ICU patients with type 1 or 2 diabetes receiving insulin infusions at greater than 0.5

unit/hour or those with stress-induced hyperglycemia receiving at rates greater than 1 unit/hour

should be transitioned from an intravenous insulin infusion to a basal-bolus insulin regimen before

the insulin infusion is discontinued. Several criteria should be met before transitioning to a basal-

bolus regimen, including no foreseeable interruptions to nutrition for procedures, resolution of any

Transitioning from a continuous intravenous regular insulin infusion to a subcutaneous basal-bolus

regimen: A long-acting insulin such as glargine administered every 24 hours can be used for basal

coverage with initial dosing at 60%–80% of the total daily dose required from the insulin infusion.

The first dose should be administered 2–4 hours before discontinuing the insulin infusion (Crit

therapy should be incorporated into clinical decisions related to insulin dosing. Bolus insulin

regimens are designed with rapid-acting, short-acting, or regular insulin doses to be provided as

scheduled doses before meals and/or correction doses based on BG measurements (i.e., every 4–6

hours); correction doses based on BG measurements may be more appropriate for patients receiving

continuous forms of nutrition support such as EN or PN. A protocol for using intermediate-acting

insulin (NPH [neutral protamine Hagedorn]) has also been described for basal insulin coverage

in patients receiving continuous enteral nutrition (JPEN J Parenter Enteral Nutr 2013;37:506-16).

Patient Case

weaned from mechanical ventilation and is being transferred from the ICU to the floor. Her current PN

formulation is 200 g of dextrose (1.8 mg/kg/minute), 110 g of amino acids, and 80 g of lipids (1.1 g/kg/day),

which meets her goal requirements at 26 kcal/kg/day and 1.5 g/kg/day of protein. It contains regular human

insulin at 20 units/day. During the past 24 hours, her fingerstick BG measurements have been 170–210 mg/

dL, and her serum glucose concentration is 182 mg/dL. She has received 14 units of sliding-scale regular

human insulin coverage. Which would be best to suggest for optimal glycemic control?