Problems after surgery

There is a risk of problems or complications after any operation.

Possible problems after bowel cancer surgery include a leak where the surgeon has joined the ends of your colon together, or your bowel not working properly. Other risks include infection, blood clots and bleeding. 

Many problems are minor but some can be life threatening. Treating them as soon as possible is important.

A leak where the ends of your colon are joined

Leaks can happen where the surgeon joins the ends of your colon together. This is called an anastomotic leak. This is a serious problem and you need to have treatment straight away.

Treatment includes:

  • stopping eating and drinking
  • antibiotics

This might be enough to heal the leak. But some people need more surgery to repair the leak if other treatments don’t work. This operation will usually involve you needing a stoma.

Bowel not working

Your bowel might be slow to start working after surgery. 

Treatment includes:

  • stopping eating and drinking and having fluids through a drip
  • a tube down your nose into your stomach (nasogastric tube) to drain bile and stop you feeling sick

This usually gets better with time. But some people need more surgery if there is a blockage in the bowel. It is very rare to develop a blockage very soon after a bowel cancer operation.

Other risks

After any major operation there is a risk of: 


You are at risk of getting an infection after an operation, such as a wound, chest or urine infection. You will have antibiotics to reduce the risk of developing an infection after surgery. Tell your doctor or nurse if you have any symptoms of infection.

They include:

  • a high temperature
  • shivering
  • feeling hot and cold
  • feeling generally unwell
  • cough
  • feeling sick
  • swelling or redness around your wound

Occasionally for an infection in your wound or pelvis, you may need another operation.

Blood clots

Blood clots (deep vein thrombosis, DVT) are a possible complication of having surgery because you might not move about as much as usual. Clots can block the normal flow of blood through the veins. Let your doctor or nurse know if you have an area in your leg that is swollen, hot, red or sore.

There is a risk that a blood clot can become loose and travel through the bloodstream to the lungs, causing a blockage there (a pulmonary embolism). Symptoms include:

  • shortness of breath
  • chest pain
  • coughing up blood
  • feeling dizzy or light headed
If you have any symptoms of a blood clot when you are at home, see your GP or go to your nearest accident and emergency department (A&E).

To prevent clots it's important to do the leg exercises that you were taught by your nurse or physiotherapist. Your nurse might also give you an injection just under the skin to help lower the risk whilst you are in hospital. You might need to carry on having these injections for 4 weeks, even after you go home. This depends on the type of operation you had.

Your nurse might teach you to do these injections yourself before you go home. Or a district nurse might come to your home to do them.

It's important to continue wearing compression stockings if you have been told to by your doctor.


There is a risk that you will bleed after your operation. The team looking after you will monitor you closely for signs of bleeding. The treatment you need depends on what is causing the bleeding and how much blood you lose. You might need a blood transfusion.

Life after bowel surgery

Having sex

You will need time to get over surgery before having sex again. Give yourself at least six weeks after major surgery.

The effects mentioned below don't affect everyone who has bowel cancer treatment. Some of the problems may get better over time. But some changes can be permanent. You may feel very embarrassed to talk to doctors or nurses about sexual problems. But if you tell them about any problems you have, they can find ways of helping you to deal with them.

An operation involving the rectum can affect the nerves to the sex organs. A man may not be able to get, or keep an erection, or might have problems with orgasm and ejaculation. Women might also notice changes. 

You may have surgery for cancer in your lower rectum, to remove your anus and rectum. If you're used to having anal sex, you will no longer be able to. Your surgeon and specialist nurse will talk to you about this before and after your surgery. Sharing your thoughts and feelings with your partner can help with this.

Your bowels

After surgery you might notice changes to your bowels including:

  • pooing more often
  • having little or no warning that you need to poo or pass wind
  • changes to your poo such as loose runny poo (diarrhoea) or hard, difficult to pass poo (constipation)
  • feeling bloated and passing wind
  • difficulty emptying your bowel completely when you poo

Your bowel habits might never return to how they were before your cancer treatment. But things should settle so that you develop a new ‘normal’ pattern. It might feel difficult at first. But remember that it’s likely to get better over time. Your specialist nurse or doctor can advise you about what you can do to manage these changes.

Last reviewed: 
04 Feb 2022
Next review due: 
04 Feb 2025
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