Diabetes and surgery patient passport
Find out more about the steps you can take to improve your diabetes control and what to expect before, during and after your operation.
Download this information in pdf format by following the link on the right.
How diabetes affects your surgery
Diabetes can affect the body’s ability to heal after an operation. Before you have your operation, it’s important to have the best possible control of your diabetes. This will give you the best outcome and a quicker recovery from your operation.
This information explains the steps you can take to improve your diabetes control and what to expect before, during and after your operation.
Download a copy of this information and bring it to your pre-operative assessment appointments, and to hospital on the day of your operation. It provides important information for you and medical staff.
What are the risks of poorly controlled diabetes and surgery?
Research shows that people with poorly controlled diabetes have increased risk of complications after their surgery. This can include slower wound healing, infections and a prolonged hospital stay.
Before your operation, you’ll need an HbA1c blood test. Your GP practice nurse can do this. If you have a high HbA1c level, the risks of surgery can outweigh the benefits. To make the surgery safe for you to have, we may need to postpone or cancel it until your diabetes is well controlled.
Before your operation
To improve your diabetes control, you can:
- be a healthy weight
- have well controlled blood pressure
- have had your HbA1c checked within the last 6 months
- attend pre-operative appointments to review your diabetes
- make any adjustments needed to your medication or lifestyle.
Discuss with your practice nurse if you need help with any of these issues.
What happens during pre-operative clinic appointments?
Before your operation, a hospital doctor or nurse will assess your diabetes control either by telephone or in person.
They’ll advise you about your HbA1c blood test, weight and blood pressure control results. If these are too high, they’ll give advice such as diet and exercise, smoking cessation and medication changes. This advice will help to make your operation safer for you. It’s very important that you follow it.
What changes might happen with my medication?
Often, we may need to stop or change your medication dose medication before surgery. For example, we may need to remove your blood pressure medication the day before surgery. We may also need to remove or reduce the dose of your diabetes medication the day before surgery.
We make these changes on an individual basis. It’s that important you understand what medication you normally take and what changes we make before surgery.
Recording medication changes
On the download copy of this information, there’s a section for you or your healthcare professional to record your medication changes.
The day of your surgery
You’ll need to fast before your operation.
If your operation’s in the morning:
- Do not eat food after 2 am on the day of the operation
- Do not drink anything containing milk or fizzy drinks such as Lucozade as they count as food
- Drink water. Have a final 1 to 2 glasses of water at 6am – it’s essential you do this
- Do not drink anything after 6am.
If your operation’s in the afternoon:
- Do not eat food after 7 am on the day of the
- Please note drinks with milk in them and fizzy drinks such as lucozade count as
- Please continue drinking water and have a final 1-2 glasses of water at 11am, it is vital you do
- Do not drink anything after 11.
How will fasting affect my blood glucose?
Many people worry that fasting for an operation will cause low blood glucose. However fasting before surgery is essential to reduce the risk of aspiration on stomach contents into the lungs. You should monitor your blood glucose closely, up to hourly, during this time.
If you have episodes of low blood glucose or ‘hypos’, bring glucose tablets, glucogel or a non fizzy sugary drink with you to hospital. We do not advise you to bring your usual fizzy drinks or juice.
We’ll measure your blood glucose before the operation. If it’s low, we’ll tell you how many glucose tablets to take. If you do not have any glucose tablets, we’ll give you glucogel to increase your blood glucose to a safe level.
If you feel unwell, or think your blood glucose might be low, tell us and we can measure your blood glucose.
What should I bring to hospital?
Bring a download copy of this information (follow the link on the right).
You should also bring:
- your normal medications in their original packaging (you may also find it useful to bring or take a photo of your prescription list on your phone)
- a note of the number of insulin units you inject and their times
- your insulin injection device, needles and any other equipment you need
- glucose tablets if you get low blood glucose
- blood glucose monitor and test strips if you use one at home
- your diabetes specialist’s name and contact details
- change (coins) if you use the hospital car park.
How do I manage my diabetes after the operation?
Many people find that their blood glucose is higher or lower for several days after their operation. This is common because of the stress of surgery and changes in your activity level. You may need to adjust your insulin/oral medication.
It’s very important to keep your diabetes well controlled after surgery. Aim for blood glucose readings less than 12mmol/L.
If you have any concerns about your blood glucose readings after surgery, please contact your practice nurse or GP at your surgery. If you have type 1 diabetes with access to the helpline, you can also call for advice.
It’s important to follow advice about your diabetes medication. Keep your discharge letter safe which will include any changes to your medication.
Type 1 diabetes – what should I do if my glucose is high or I feel unwell?
If you have type 1 diabetes you must:
- stay hydrated – aim to sip 2.5 to 3.5 litres of water each day
- see your GP if you think you have an infection or any other concerns
- measure your blood glucose 4 times a day. If it’s greater than 11.0mmol/L, you’ll need to test for blood ketones.
Understanding blood ketones
Less than 0.6 mmol/L is normal.
If it’s 0.6 to 1.5 mmol/L, test it again in 2 hours.
1.6 to 2.9 mmol/L means you’re at risk of diabetic ketoacidosis. It’s a serious condition so you must contact your GP or diabetes team.
Greater than 2.9 mmol/L means you have a high risk of diabetic ketoacidosis. You must get immedicate medical attention.
Adjusting insulin doses
If your blood glucose is:
- 11 to 17 mmol/L, add 2 units of insulin to each dose
- 17 to 22 mmol/L, add 4 units of insulin to each dose
- greater than 22 mmol/L, add 6 units of insulin to each dose.
If you have type 1 diabetes and know your own correction dose, please use your correction ratio.
If you start vomiting, can not keep fluids down, or can not control your blood glucose or ketone levels, you must seek urgent medical advice from your GP, nurse, or helpline if you have access.
You can also call 111.
Even if you’re not eating, never stop your insulin. If your blood glucose is4.0 mmol/L or less, take your usual hypo treatment such as dextrose tablets.
Type 2 diabetes – what should I do if my glucose is high or I feel unwell?
Follow the sick days rules. You must:
- stay hydrated. Aim to sip 5 to 3.5 litres of water a day
- see your GP if you think you have an infection as you may need antibiotics
- monitor your blood glucose levels more frequently if you can
- contact your GP or practice nurse if your readings stay high, you feel very unwell or you’re not sure what to do.
If you take tablets or a non-insulin injection, follow these instructions.
If you have diarrhoea or vomiting and take metformin or an SGLT2 inhibitor (dapagliflozin, empagliflozin, canagliflozin, ertugliflozin), stop taking your medication until you’re rehydrated and drinking well.
If you take gliclazide you may need to increase the dose or even need insulin injections for a short time.
If you have a non-insulin injection and develop abdominal pain, nausea and vomiting, stop the injections and seek urgent medical attention.
Contact your GP if your blood glucose levels are persistentlt above 15 mmol/L.
If you take insulin
Monitor your blood glucose four times a day, even if you ‘re not eating. If your blood glucose is persistently greater than 11 mmol/L, you need to adjust your dose.
If your blood glucose is:
- 1 to 17 mmol/L, add 2 units of insulin to each dose
- 1 to 22 mmol/L, add 4 units of insulin to each dose
- greater than 22 mmol/L, add 6 units of insulin to each dose.
You must reduce any adjustments gradually as you start to feel better. Contact your GP or specialist nurse if you’re unsure about adjusting your dose.
If your blood glucose is 0 mmol/L or less, reduce your insulin by 20% and ensure your have hypo treatments such as dextrose tablets.