Chapter 46: Common Metabolic Problems on the Neurology Wards

PART 1—GENERAL CARE OF THE HOSPITALIZED DIABETIC PATIENT

How do I manage glycemic control in a diabetic patient admitted for a neurological condition?

Factors to consider:

1. Stress of illness, abrupt changes in caloric intake, and physical activity will change her metabolic state and insulin requirements

2. Need for NPO status for procedures or tests

3. Interactions between some oral hypoglycemic agents and intravenous contrast on kidney function

4. Neurological conditions that will affect nutrition (dysphagia)

National guidelines recommend blood glucose between 140 and 180 mg/dL in critically ill patients and pre-meal glucose of less than 140 mg/dL and random glucose of <180 mg/dL in noncritically ill patients.¹

How do I manage a patient that is taking oral hypoglycemic agents?

Oral hypoglycemic agents are often temporarily discontinued during hospitalization because of contraindications (renal failure, need for contrast, NPO status, heart failure). These agents could be restarted at discharge if metabolic status returns to previous baseline.

How do I dose insulin?

The majority of hospitalized patients with DM will require some form of insulin coverage during their admission. The goal for hospitalized patients requiring insulin is to provide a baseline minimum insulin coverage throughout the day to combine with additional doses to match the nutritional needs.

• Sliding scale insulin (SSI) are protocols adopted that provide predetermined amount of subcutaneous regular insulin based on glucose levels checked after meals or every 6 hours for patients on NPO status or on continuous enteral feeds. Relying on SSI alone is not enough, as it addresses hyperglycemia only after it occurs and has been associated with excessive hyperglycemia in hospitalized patients when used alone.² It can be used initially to estimate insulin coverage for patients who are insulin naïve, newly diagnosed with DM, or cannot continue oral hypoglycemic agents. A sliding scale order could accompany a basal bolus regimen to temporarily correct any increase in demand during neurological illness (insulin correction).

• Basal bolus correction. This strategy consists in the administration of an intermediate or long-acting dose insulin (NPH, glargine, detemir) and a short-acting dose insulin (lispro, aspart, and glulisine) provided before meals (or soon after if food intake is uncertain) to mitigate the hyperglycemic response. Calculation of the dose is based on AM glucose and previous insulin requirements (Figure 46-1).