Patients with Insulin Treated Diabetes Undergoing Surgery
You are due to have an operation which will mean that you will be asked to omit at least one meal. This leaflet gives advice about what you should do about your diabetes treatment before and after the surgery.
Before your operation, please follow the instructions below.
If your operation is in the morning
- Do not take any food or drink other than water from six hours before the time you are asked to come to hospital.
- You may drink water until two hours before you come to hospital
- Check your blood glucose from 6am every two hours before you arrive at hospital
- If you are driving, check your blood glucose before starting the car and drive only if your blood glucose is more than 5mmol/l
- Please inform staff at the hospital if you have needed to take any hypo treatment because it is possible that your surgery may have to be rearranged for another day.
If your operation is in the afternoon
- Eat breakfast before 7am and take no food or drink other than water after this time
- You may drink water until two hours before you come to hospital
- Check your blood glucose level before breakfast and every two hours before you arrive at hospital
- If you are driving, check your blood glucose before starting the car and drive only if your blood glucose is more than 5mmol/l
- Please inform staff at the hospital if you have needed to take any hypo treatment because it is possible that your surgery may have to be rearranged for another day
How to treat hypoglycaemia or low blood glucose levels 4mmol/L or less
You can treat immediately with one of these options of quick-acting glucose treatments:
- 200ml (a small carton) of smooth orange juice
- five glucotabs
- six dextrose tablets
- five jelly babies.
You can repeat one of these treatments if you do not feel better after 10 minutes (or if your blood glucose level is still less than 4mmol/L). For further information on how to treat hypoglycaemia or low blood glucose levels less than 4mmol/L please visit the Trend Diabetes website.
Things to bring with you to hospital
- Hypo treatments (glucose drink, tablets or jelly babies)
- Blood glucose testing equipment you usually use
- Insulin you usually take for your diabetes, labelled with your name.
During your operation
If you are likely to miss more than one meal, or if your blood glucose is high at the time of the operation, you may be given an intravenous insulin infusion (a combination of insulin and fluid given into a vein). This will be continued until you are ready to eat and drink and will be discontinued once you have taken your usual insulin.
After your operation
It is not uncommon to experience changes in blood glucose levels after your operation. Your blood glucose will be monitored after the operation and additional insulin given if necessary. The glucose targets may change for safety reasons.
After your operation you will be offered food and drink when you feel able to eat.
Once you are eating and drinking normally, you should restart your normal insulin from that meal onwards. Your blood glucose levels may be higher than usual for a day or so.
At home
Continue taking your usual medication and insulin as advised by your healthcare team.
Monitor your blood glucose levels more often as these may be higher than usual for a day or so. This is not a problem unless you are feeling unwell.
If you feel unwell, especially if you are vomiting and unable to eat or take medication, please seek medical attention.
For more information on what to do when you are ill, please access the useful documents on the Trend website.
Type 1 Diabetes: What to do when you are ill
Type 2 Diabetes: What to do when you are ill
Contact your usual diabetes team/GP surgery or local out-of-hours service for advice. If you usually attend the hospital for diabetes care, please telephone the Diabetes team on 01305 255342.
What to do with your insulin before surgery
Long-acting insulin
Examples: Abasaglar®, Humulin® I, Insulatard®, Insuman® Basal, Lantus®, Levemir®, Semglee®, Tresiba®, Toujeo®, Xultophy®
| Frequency/timing of long-acting insulin | Day before admission | Day of surgery if your operation is in the morning | Day of surgery if your operation is in the afternoon |
|---|---|---|---|
| Once daily long acting (morning) | No dose adjustment necessary | Give 80% of usual dose and check blood glucose on admission | Give 80% of usual dose and check blood glucose on admission |
| Once daily long acting (lunchtime) | Give 80% of usual dose. | Check blood glucose on admission Restart at normal dose when eating and drinking | Check blood glucose on admission Restart at normal dose when eating and drinking |
| Once daily long acting (evening) | Give 80% of usual dose | No dose adjustment necessary Check blood glucose on admission | No dose adjustment necessary Check blood glucose on admission |
| Twice daily long acting | Morning dose stays the same, evening dose will need to be given at 80% of usual dose | Give 80% of usual morning dose Evening dose unchanged Check blood glucose on admission | Give 80% of usual morning dose Evening dose unchanged Check blood glucose on admission |
Short-acting insulin with meals
Examples: Actrapid®, Apidra®, Fiasp®, Humalog®, Humulin® S, Porcine Neutral, Insuman® Rapid, Lyumjev®, Novorapid®
| Short-acting insulin | Day before admission | Day of surgery if your operation is in the morning | Day of surgery if your operation is in the afternoon |
|---|---|---|---|
| Short-acting insulin with meals (2 – 4 doses a day) | No dose adjustment necessary | Omit morning dose if no breakfast is eaten Check CBG on admission Omit lunchtime dose if not eating and drinking normally Resume normal insulin with evening meal if eating a normal meal If eating half or a small meal, give half usual dose If not eating, give basal long-acting only component (see above) | Take usual morning insulin dose with breakfast Omit lunchtime dose if not eating Check CBG on admission Resume normal insulin with evening meal if eating a normal meal If eating half or a small meal, give half usual dose If not eating, give basal only long-acting component (see above) |
Premixed insulin prepared by manufacturers
Examples: Humulin® M3, Humalog® Mix 25, Humalog® Mix 50, Hypurin® Porcine 30/70 Mix, Insuman® Comb 15, Insuman® Comb 25, Insuman® Comb 50, Novomix® 30
| Frequency of premixed insulin | Day before admission | Day of surgery if your operation is in the morning | Day of surgery if your operation is in the afternoon |
|---|---|---|---|
| Twice daily (premixed insulin) | No dose adjustment necessary | Half usual morning dose Check blood glucose on admission Resume usual insulin with evening meal if eating a normal meal If eating a half or small meal, give half usual dose If not eating, start VRIII | Half usual morning dose Check blood glucose on admission Resume usual insulin with evening meal if eating a normal meal If eating a half or small meal, give half usual dose If not eating, start VRIII |
| Three times per day (premixed insulin) | No dose adjustment necessary | Half usual morning dose Check blood glucose on admission Omit lunchtime dose Resume normal insulin with evening meal if eating a normal meal If eating a half or small meal, give half usual dose If not eating, start VRIII | Half usual morning dose Check blood glucose on admission Omit lunchtime dose Resume normal insulin with evening meal if eating a normal meal If eating a half or small meal, give half usual dose If not eating, start VRIII |
Self-mixed insulin prepared by patient/carer
Examples: Short-acting: Actrapid®, Apidra®, Fiasp®, Humalog®, Humulin® S, Hypurin®Porcine Neutral, Insuman® Rapid, Lyumjev®, Novorapid® and Intermediate-acting: Humulin® I, Hypurin® Porcine Isophane, Insulatard®
| Self-mixed insulin frequency | Day before admission | Day of surgery if your operation is in the morning | Day of surgery if your operation is in the afternoon |
|---|---|---|---|
| Twice daily (two different types of insulin combined by the patient or carer into one injection) | No dose adjustment necessary | Calculate total dose of both morning insulins and give half of this total dose as intermediate acting insulin only, in the morning Check blood glucose on admission Resume usual insulin with evening meal if eating a normal meal If eating half or small meal, give half usual dose If not eating, start VRIII | Calculate total dose of both morning insulins and give half of this total dose as intermediate acting insulin only, in the morning Check blood glucose on admission Resume usual insulin with evening meal if eating a normal meal If eating half or small meal, give half usual dose If not eating, start VRIII |
Contact numbers
We hope that you have found this information useful. If you have any questions or are worried about anything, please speak to the Pre-operative Assessment Unit on 01305 254222 or the diabetes nurse specialist on 01305 255342.
About this leaflet
Authors: Amelia Denham, Deputy Sister, Pre-assessment Department and Dr Claire Joannides Consultant Anaesthetist and Pre-assessment Lead and Dr Mo-Lee Wong, Consultant Diabetes and Endocrinology
Written: February 2023
Approved: October 2023
Review date: October 2026
Edition: v1
If you have feedback regarding the accuracy of the information contained in this leaflet, or if you would like a list of references used to develop this leaflet, please email patientinformation.leaflets@dchft.nhs.uk
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