How surgery can affect your diabetes

If you have diabetes, you are more likely to develop problems during and after surgery. Your operation will be carefully planned and you will be closely monitored.

Before the operation, tell the doctors you have diabetes. Talk to your diabetes team too. They can talk to your surgeon and make sure you get the best advice to help you prepare for surgery.

You should not eat or drink anything for a few hours before the operation. This is to help reduce the risk of you being sick. The nurse or doctor will talk to you about managing your diabetes when you are not eating. You may be given a drip of sugar and insulin to help keep your blood sugar levels well-controlled.

You will be encouraged to manage your diabetes again as soon as possible after your operation. This may be difficult at first. The ward nurses will help you and will check your blood sugar levels regularly. You will not be expected to manage your diabetes yourself until you are fit enough.

What is surgery?

Surgery means treating illness by cutting away body tissue. It’s one of the main treatments for many cancers. The type of surgery you have and how it may affect you will vary depending on the type of cancer you have.


How surgery can affect your diabetes

Having diabetes may increase your risk of problems during and after surgery. For example, you may heal slower than someone who does not have diabetes. You are also more likely to get a wound infection if your blood sugar levels are not well-controlled. We have more information about these side effects of treatment.

If you have an operation to remove the pancreas, you will no longer be able to produce insulin to control your blood sugar. After surgery, you will need to start injections of insulin and regularly test your blood sugar levels. A diabetes specialist team will support you with this.

If you have had part of the pancreas removed, the remaining pancreas may not be able to make enough insulin straight away. This means your blood sugar levels won't be controlled. You may need to have an insulin drip into a vein, called an infusion. You will usually only have this until the remaining pancreas recovers and starts to make insulin again. The ward staff will closely monitor your blood sugar during this time. If you don't already have diabetes, there is an increased risk of developing it in the future after this operation.

I am not on insulin but take tablets. The only time it became a problem was when I needed surgery for a hysterectomy, so I was put on a drip.

Clare


Planning your operation

To help prevent problems, your operation should be carefully planned and you will be closely monitored. Most operations for cancer are planned in advance, so you will have time to prepare.

You can help reduce the risk of any problems by keeping your diabetes as well-controlled as possible in the weeks before your operation. Your diabetes team can help you with this.

Before your operation, you should have an appointment at a pre-surgery assessment clinic. This is to discuss the plan for your care. Tell the doctors that you have diabetes and about any problems you have. Having surgery can be more risky if you have problems because of diabetes, such as problems with your heart, eyes or kidneys, or if you have lost any feeling in your feet. Your doctor may arrange for you to have tests to check your health before your operation.

Talk to your diabetes team about your operation. They can talk to your surgeon and make sure you get the best advice to help you prepare for surgery. This advice will depend on how you manage your diabetes:

  • If you take tablets, you may be asked to stop them for a short time before and after the operation.
  • If you use insulin, you may need to change the dose. You should not stop taking insulin.

Ask for some written information so you know exactly what you need to do and when.

You will also usually meet the doctor who puts you to sleep and makes sure you are safe during the operation (the anaesthetist). They will tell you how they will care for you and control your blood sugar during surgery.


The day of your operation

You will normally be admitted to hospital on the morning of your operation. Sometimes you may be asked to come in the day before the operation, so that the nurses can monitor your blood sugar levels. You may have a drip (infusion) of sugar and insulin to help keep your blood sugar levels well-controlled.

Your doctor will ask you not to eat or drink anything for a few hours before the operation. This is to help reduce the risk of you being sick.

Where possible, you should be the first person on the operating list for that morning or afternoon. This will help reduce the amount of time you cannot eat. The nursing and medical staff will plan the best way to manage your diabetes when you are not eating. This will depend on how long you cannot eat:

  • If you miss one meal, you should be able to control your diabetes by adjusting your normal routine.
  • If you miss two or more meals, you may need a drip of sugar and insulin for a short time. The amount of insulin you have will vary depending on your blood sugar level. Your nurses will regularly check this.

Having an operation can put you at risk of developing a blood clot in the leg. Compression stockings (also known as anti-embolic stockings) help to reduce this risk. You might be asked to wear a pair of compression stockings during your operation and for some time afterwards. But you should not wear them if you have any problems with feeling or circulation in your feet.


After your operation

You will be encouraged to look after your diabetes again as soon as possible after your operation. The nursing staff will help you do this. You may have trouble controlling your blood sugar at first. This may be because you are:

  • not allowed to eat normally
  • being sick
  • in pain
  • less active than normal
  • stressed.

The nurses on the ward will check your blood sugar levels regularly. You will not be expected to manage your diabetes yourself until you are fit enough.

You will keep having the drip of sugar and insulin until you can start eating and drinking again. Some people will be able to eat very soon after their operation. For others, it may take longer. This will depend on the type of operation you have had. Your doctors will try to get you eating your normal diet as soon as possible. They will tell you how soon you can start eating and drinking again, and when you should start taking your usual diabetes medicines.

If you are in bed for a long time, you are at risk of developing bedsores (pressure sores). It is important that you move around the bed and change your position regularly. This is especially important if you have less feeling in your hands and feet, as you may not feel if you are developing a sore. You will be encouraged to get up fairly soon after your operation. The ward staff will help you with this if needed. Moving around will also help your blood sugar levels to return to normal.

Your nurse or doctor will tell you when you can go home. You may have to stay in hospital slightly longer than someone who doesn't have diabetes.

Any stitches, clips or staples in your wound are usually taken out 7 to 10 days after the operation. The wound may take longer to heal if your blood sugar levels are not well-controlled. Your practice nurse can remove any stitches. If you can’t leave home, a district nurse can visit you.

If your diabetes is not well-controlled, you are more at risk of developing an infection. It’s important to let your nurse or doctor know straight away if your wound becomes hot, painful or begins to bleed or leak any fluids, even after you go home.