A hemicolectomy is a surgical procedure involving the removal of a segment of the colon. A hemicolectomy may help treat colon cancer and bowel diseases, such as Crohn’s disease or severe diverticulitis.

During a hemicolectomy, a surgeon removes a damaged section of the intestine and reattaches the healthy parts of the colon.

In this article, we explain why a person would have a hemicolectomy, how a surgeon performs it, ways to prepare, and what to eat after surgery.

two surgeons performing a hemicolectomyShare on Pinterest
A doctor may suggest a hemicolectomy to treat certain bowel conditions.

The colon, or large intestine, sits inside the abdominal cavity. It starts in the iliac region of the abdomen and continues across the width of the abdominal cavity. The colon then travels down the left side of the abdomen and ends at the anus.

One of the main functions of the colon is to regulate water levels in the body. The colon absorbs water from food. It also absorbs some vitamins and processes waste for expulsion from the body.

Trauma can damage the colon, as well as various diseases, including:

If colon cancer develops, a doctor will often recommend surgery to remove the tumor or part of the large intestine.

In instances of bowel disease, surgery may be necessary to remove the diseased or damaged section of the large intestine.

During a hemicolectomy, a surgeon only removes one side of the colon. Which side of the colon the surgeon removes depends on the location of the tumor or diseased tissue.

Removal of a section of the colon will not affect a person’s ability to digest food.

Learn more about the anatomy of the colon here.

A surgeon can perform a hemicolectomy using either laparoscopic or open surgery.

Laparoscopic procedure: During a laparoscopic procedure, the surgeon makes small incisions in the abdominal wall and inserts a thin scope. The scope has a lens and light for viewing purposes. The surgeon then inserts surgical instruments through the small cuts in the abdomen.

This type of procedure is also known as keyhole surgery. If a surgeon cannot carry out the operation by this method, they will need to use open surgery.

Open surgery: An open hemicolectomy involves making longer cuts in the body to access the colon. Since the cuts are larger with an open procedure, recovery may take longer.

The colon consists of three parts:

  • the ascending colon, which attaches to the small intestine
  • the descending colon, which attaches to the rectum
  • the transverse colon, which is between the ascending and descending colon

Types of hemicolectomy

A hemicolectomy may involve removing a portion of the colon on the right or left side.

  • Right hemicolectomy: A surgeon removes the ascending colon. Afterward, they reattach the transverse colon to the small intestine.
  • Left hemicolectomy: A surgeon removes the descending colon before reattaching the transverse colon.

Preparation for a hemicolectomy varies, depending on a person’s overall health and the medications they may be taking.

Typically, a doctor will perform tests before the surgery to make sure the individual is an appropriate candidate for a hemicolectomy. These tests include an electrocardiogram (EKG) and blood tests.

A person may need to stop taking certain medications, such as blood thinners, for a specific time ahead of surgery. However, it is essential only to stop medications on a doctor’s instruction.

People will need to fast for 12 hours before their procedure. They may also need a bowel prep, which involves taking a laxative to clean out the colon.

Some individuals notice very little change in their digestion after the removal of colon tissue.

However, some people experience cramps or diarrhea. A doctor might recommend drinking more water and following a bland diet to help control bowel movements.

A bland diet will have foods that reduce the risk of inflammation and may include:

  • lean meat, poultry, and fish
  • dried beans
  • nuts and nut butter
  • any fruits except for citrus
  • any vegetables
  • low fat or nonfat milk and dairy

It is important to avoid added fats, caffeine, and alcohol, as well as condiments and foods with intense or spicy flavors.

People should also avoid doughnuts, rich desserts, and chocolate.

Read more on the bland diet here.

A hemicolectomy can be an effective treatment for digestive diseases and cancers. However, as with any surgery, the procedure may present risks.

While it may not be possible to prevent all complications, following the doctor’s recommendations after the procedure may decrease the risks.

Excessive bleeding

If a person has an open hemicolectomy instead of laparoscopic surgery, there is a higher chance of excessive bleeding

In some cases, the doctor may carry out a blood transfusion to replace blood loss.

Internal injury

During the procedure, damage to the bladder or surrounding organs may occur. Additional surgery may be necessary, depending on the extent of the damage. If an internal injury occurs, this may delay recovery.

Anastomotic leak

When a surgeon removes the diseased section of the colon, they sew the healthy segments together. The site where the colon reattaches is called an anastomosis.

After a hemicolectomy, the colon can leak at the point of the anastomosis. Symptoms of a leak may include nausea, vomiting, and stomach pain.

An anastomotic leak can be life threatening. Recent research suggests the risk of fatality within 60 days of surgery due to anastomotic leak is 3.1%.

Either way, an anastomotic leak can be a dangerous surgical complication. A person should seek immediate medical attention if they notice the symptoms.


Infections can develop during or after any intestinal surgery, including a hemicolectomy. An infection will usually need treatment with antibiotics and may lead to a longer hospital stay.


One risk of a hemicolectomy is if the surgeon is unable to reattach the remaining colon to another part of the intestine or the rectum.

When reattachment is not possible, the surgeon may need to perform a colostomy for some people. This procedure involves attaching the colon to the abdominal wall and creating an opening, or stoma.

The surgeon attaches a colostomy bag to the stoma to collect the body’s waste. A colostomy may be permanent or temporary.

Recovery from a hemicolectomy depends on whether the procedure is laparoscopic or open surgery. However, recovery is likely to take 1–2 months.

A person’s underlying health condition may also affect recovery. In many instances, a hemicolectomy without complications requires a hospital stay of 3–7 days.

Typically, a bladder catheter will remain for 1–2 days after the procedure to drain urine from the body. The surgeon may also insert abdominal drains to remove fluids.

An anesthetist will usually administer pain medication through an epidural, which they insert into the person’s back, near the spine. After removing the epidural, a medical team may administer oral pain medications.

Although it can vary, people can usually resume eating and drinking as soon as they feel ready. However, it may take 6–8 weeks before they can resume their regular diet.

The doctor may encourage a person to start walking as soon as possible after the procedure. Walking decreases the risk of a blood clot developing and also promotes digestion.

After discharge from the hospital, a person will receive specific recovery instructions. These may include when to resume everyday activities, such as driving and lifting heavy objects.

The outlook for people who have a hemicolectomy varies, depending on the reason they needed the procedure. Some people may have to make lifestyle or dietary changes following the surgery.

People who undergo a hemicolectomy to treat a bowel disease may feel better and experience reduced symptoms after the surgery.

If the surgery took place as part of colon cancer treatment, the outlook would depend on the extent of cancer. Additional treatment, such as chemotherapy, may also be necessary.