Surgery is HUGE STRESS -
insulin requirements increase.
Annotations:
Increased catecholamines and cortisol released. Antagonise the effects of insulin.
Need to avoid ketosis and
hypoglycaemia.
Type 1 diabetics
Major elective surgery
1. Give normal insulin dose the evening
before surgery. Hence, admit day before.
2. Early morning - start infusion of KCl and dextrose (only if not
hyperkalaemic). Infuse at the fluid requirement rate - usually
125ml/hour. First on list.
Annotations:
Make up all infusions according to local infusions.
3. Piggy back a pump of insulin made up in 0.9% NaCl.
Rate according to frequent blood glucose monitoring,
and patient's fluid requirement, cardiac function, age.
Annotations:
Make up all infusions according to local protocols.
If a pump isn't available then have to add soluble insulin to the KCl and dextrose infusion, provided not hyperkalaemic. Rate is determined by the patient's fluid requirement - usually 125ml per hour (3 L per day). The dose of added insulin has to be adjusted to the blood glucose concentration according to local protocol.
4. Once eating and drinking, SC insulin before
breakfast, stopping IV infusion 30 mins later. Dose
may need to be 10-20% higher than usual if in bed
or unwell. 30-40 units per day is acceptable in 4
divided doses if previously not receiving insulin -
soluble insulin before meals, and intermediate before
bed.
Annotations:
Patients that were hyperglycaemic often relapse after insulin restarted. May require additional doses of insulin at any of the 4 times. Addition of a temporary IV infusion or reversion to a fully IV insulin regimen.
Minor elective surgery
Omit the morning long acting insulin
dose. Give a soluble insulin dose, a
quarter of the total daily dose. Light
breakfast 6 hours before the surgery.
Arrange surgery for between 12pm to 5pm.
Arrange an appropriate calorie and
carbohydrate loaded meal in the evening.
Light meal with 10-20 soluble insulin
according to the blood glucose.
Emergency surgery
Same as for elective major surgery, except
more insulin is likely if there is ketosis. Ketosis
should be controlled before surgery.
Type 2 diabetics
Minor surgery - well controlled
Omit the morning dose of
oral hypoglycaemic.
More than minor surgery
Monitor blood glucose - use insulin SC or IV if too high