Table 1.

Guideline for peri‐operative adjustment of insulin (short starvation period – no more than one missed meal)

Insulin	Day before admission	Day of surgery		Whilst a VRIII is being useda
		Surgery in the morning	Surgery in the afternoon
Once daily (e.g. Lantus®, Levemir®, Tresiba®, Insulatard®, Humulin I®, Insuman®)
Evening	Reduce dose by 20%	Check blood glucose on admission	Check blood glucose on admission	Continue at 80% of usual dose
Morning	Reduce dose by 20%	Reduce dose by 20%; check blood glucose on admission	Reduce dose by 20%; check blood glucose on admission	Continue at 80% of usual dose
Twice daily
Biphasic or ultra‐long acting (e.g. Novomix 30®, Humulin M3®, Humalog Mix 25®, Humalog Mix 50®, Insuman® Comb 25, Insuman® Comb 50, Levemir®, Lantus®) by single injection, given twice daily	No dose change	Halve the usual morning dose; check blood glucose on admission; leave evening meal dose unchanged	Halve the usual morning dose; check blood glucose on admission; leave the evening meal dose unchanged	Stop until eating and drinking normally
Short‐acting (e.g. animal neutral, Novorapid®, Humulin S®, Apidra®) and intermediate‐acting (e.g. animal isophane, Insulatard®, Humulin I®, Insuman®) by separate injections, both given twice daily	No dose change	Calculate total dose of morning insulin(s); give half as intermediate‐acting only in the morning; check blood glucose on admission; leave evening meal dose unchanged	Calculate total dose of morning insulin(s); give half as intermediate‐acting only in the morning; check blood glucose on admission; leave evening meal dose unchanged	Stop until eating and drinking normally
Three to five injections daily
	No dose change	Basal bolus regimens: Omit morning and lunchtime short‐acting insulins; keep basal unchangeda Premixed morning insulin: Halve morning dose and omit lunchtime dose; check blood glucose on admission	Give usual morning insulin dose(s); omit lunchtime dose; check blood glucose on admission	Stop until eating and drinking normally

^aIf the patient requires a VRIII then the long‐acting background insulin should be continued but at 80% of the dose the patient usually takes when he/she is well.

VRIII, variable‐rate intravenous insulin infusion.