Hyperglycemia & Hypoglycemia

Please refer to the Nursing Pocket Card Managing Acute Diabetic Complications.

Hyperglycemia (Lippincott Procedures, 2020)

• In hospitalized patients, hyperglycemia is defined as blood glucose greater than 140 mg/dL (7.8 mmol/L).
• Signs and symptoms include increased thirst, increased urination, weight loss, headache, decreased energy level and blurry vision.
• Causes (other than diabetes) include stress from infection, acute illness, or surgery.
• Treat with correctional insulin as needed and prescribed.

Hypoglycemia (Lippincott Procedures, 2020; ADA, 2022)

• Hypoglycemia in hospitalized patients is categorized by the following:
  • Level 1 hypoglycemia: glucose level 54-70 mg/dL (3.0-3.9 mmol/L)
  • Level 2 hypoglycemia: glucose level less than 54 mg/dL (3.0 mmol/L); requires immediate glucose correction.
  • Level 3 hypoglycemia: a clinical event with a change in mental and/or physical functioning that requires assistance from another person for recovery; requires immediate glucose correction.
• Early symptoms include shakiness, weakness, sweatiness, hunger, dizziness, light-headedness, palpitations, and anxiety.
• Central nervous system signs and symptoms include vision changes, gait disturbances, changes in affect or behavior, confusion, paresthesia, slurred speech and sleepiness progressing to coma or seizure.
• Hypoglycemia in the hospital may be caused by:
  • Improper prescribing of other glucose-lowering medications
  • Inappropriate management of the first episode of hypoglycemia
  • Nutrition-insulin mismatch (i.e., unexpected interruption of nutrition, enteral or parenteral feedings or reduced oral intake)
  • Acute kidney injury
  • Sudden decrease in corticosteroid dose
  • Poor timing of short- or rapid-acting insulin related to meals
  • Decreased infusion of intravenous dextrose
  • Delayed or missed blood glucose checks
  • Inability of patient to report symptoms

Considerations for Special Settings (American Diabetes Association, 2022)

Critical Care

• Utilize a continuous intravenous (IV) insulin infusion for glucose 180 mg/dL (10.0 mmol/L) or higher.
  • Titrate infusion carefully to prevent hypoglycemia, as prescribed.
  • Monitor blood glucose every 30 minutes to 2 hours while on a IV insulin infusion, as prescribed.
  • Titrate the infusion rate based on glycemic fluctuations using a validated written or computerized protocol.
• When transitioning patients with type 1 or type 2 diabetes from intravenous insulin to subcutaneous, administer a dose of subcutaneous basal insulin 2 hours before the intravenous insulin is discontinued. The basal dose should be based on the infusion rate during the last 6 hours of stable glucose readings.
• Failure to overlap the IV and subcutaneous insulin may result in rapid hyperglycemia and risk of diabetic ketoacidosis (DKA) in patients with type 1 diabetes.

Perioperative Care

• Recommended target glucose is 80-180 mg/dL (4.4-10.0 mmol/L).
• Perform a preoperative risk assessment for patients at high risk for ischemic heart disease and those with autonomic neuropathy or renal failure.
• Hold metformin the day of surgery.
• Hold other oral hypoglycemic agents the morning of surgery and give half the NPH dose or 75-80% of the dose of long-acting analog or pump basal insulin.
• Monitor blood glucose every 4-6 hours while NPO and treat with short-acting insulin as needed.
• Reducing insulin the evening before surgery by 25% may achieve perioperative blood glucose levels in the target range with lower risk of hypoglycemia.
• In non-cardiac general surgery patients, basal insulin plus premeal regular or short-acting insulin (basal-bolus) coverage is associated with improved glycemic control and lower rates of perioperative complications compared with sliding scale regimens.

Patient Self-Management (American Diabetes Association, 2021)

• Patients may self-manage their diabetes in the hospital if the patient has:
  • A history of successful self-management of diabetes at home
  • Demonstrated the cognitive and physical skills needed to self-administer insulin and performed self-monitoring of blood glucose
  • Adequate oral intake
  • Shown proficiency in carbohydrate estimation
  • Been utilizing multiple daily insulin injections or continuous subcutaneous insulin infusion (CSII) pump therapy
  • Stable insulin requirements
  • An understanding of sick-day management

• If self-management is used, a hospital protocol is recommended requiring that the patient, nursing staff, and provider agree that self-management is appropriate.

Continuous Subcutaneous Insulin Infusion (CSII)

Patients with continuous subcutaneous insulin infusion pumps may continue to self-manage their infusion if they are mentally and physically capable to do so.

• Confirm that the patient has the supplies required to safely manage the pump.
• Ensure a policy and procedure is in place to help guide inpatient CSII therapy.
• Document basal and bolus doses at least daily.
• If the pump is discontinued for procedures, diagnostic imaging or surgery, subcutaneous insulin should be prescribed. 

Noninsulin Therapies

• Consider discontinuing saxagliptin and alogliptin in patients who develop heart failure.
• Sodium-glucose cotransporter 2 (SGLT2) inhibitors:
  • Avoid in patients with severe illness, ketonemia or ketonuria, and during prolonged fasting and surgical procedures
  • Not recommended for routine in-hospital use
  • Discontinue 3 days before scheduled surgery

Discharge Planning 

Please refer to the Nursing Pocket Card Discharge Planning for Patients with Diabetes Mellitus.