Canterbury DHB

Ward Management

This topic provides guidance on how to manage glucose in Haematology patients who have been admitted to hospital and are starting to take corticosteroid medication.

Goals

• Avoid complications such as severe hyperglycaemia, volume depletion, and electrolyte abnormalities that could prolong hospital admission and complicate treatment.
• Identify patients who may have pre-existing undiagnosed diabetes so that appropriate treatment and follow-up can be arranged.
• Identify patients with pre-existing diabetes who may need their treatment plans adjusted.

About steroid induced hyperglycaemia

• In addition to their anti-inflammatory and immunosuppressive effects, corticosteroids have profound effects on glucose metabolism.
• Any steroid dose that is more than physiological replacement has the potential to cause glucose disruption.
• Steroid-induced hyperglycaemia (sometimes called steroid-induced diabetes) is very common.
• Steroid-induced hyperglycaemia may occur in patients with (or without) a prior history of diabetes mellitus.

Corticosteroids and their effects

Steroids usually affect blood glucose levels after food.

Example

Prednisone given at breakfast time tends to cause the highest blood sugars in the afternoon and evening but usually has less or no effect on waking blood glucose levels.

Example

Dexamethasone is a very potent steroid, particularly at doses given according to Haematology protocols. The effect on plasma glucose may be prolonged (more than 24 hours after a single dose).

Management for all patients starting corticosteroids

Check finger prick glucose regularly for the first 24 hours after starting steroids:

• before meals (breakfast, lunch, dinner)
• before bed

Depending on blood glucose levels, seek medical review

Actions

Intervention will depend on a number of factors which must be considered by the treating physician, including:

• Anticipated length of steroid course – e.g. course of steroids greater 1-2 weeks.
• Severity of hyperglycaemia – e.g. if glucose levels > 15 mmol/L.
• Presence of a pre-existing diagnosis of diabetes – likely to need treatment intensification.
• Treatment goals for the patient.

Treatment options

Refer to HealthPathways for guidance or contact the Diabetes Registrar on call (if needed).

Provided the patient is eating, insulin doses should be administered at regular times. ‘PRN’ dosing of rapid-acting insulin (e.g. NovoRapid q4hrly) should be avoided.

Patients not already on insulin

• Intermediate-acting insulin (Protaphane or Humulin NPH) given once or twice daily (before breakfast and/or dinner) effectively manages most glucose excursions.
• Start at a dose of around 0.2-0.3U/kg/day and adjust every day until target is reached.
• Correction doses of rapid-acting insulin (NovoRapid, Humalog, or Apidra) can be charted prior to meals if the pre-meal blood glucose is > 15 mmol/L. The dose required is likely to be 1/4 to 1/3 of the total daily dose of intermediate acting insulin.

Patients already on insulin

• Insulin doses may need to be adjusted, particularly insulin given prior to meals.
• Intermediate or fast-acting insulin may need to be added temporarily to the treatment regimen if a patient is on long-acting insulin alone (e.g. Lantus).

Discharge planning

Record the diagnosis of steroid-induced hyperglycaemia in the Discharge Summary.

This will alert the GP and other medical staff to the problem and allow anticipatory planning for any future courses of steroids

Encourage patients to self-monitor glucose

Make sure they have a glucose meter and testing strips. Testing should be done before breakfast and bed.

Ensure adequate follow-up arranged

If the steroid or insulin regimen is complex, request inpatient advice from a Diabetes Nurse Educator or the Diabetes Registrar on call.

All patients should be advised to see their own GP for review following discharge.

Topic Code: 284655