Review question

Does closing defects after Roux-en-Y gastric bypass (RYGB) in bariatric surgery prevent internal hernias?

Key messages

• Due to a lack of evidence, it is unclear whether closing defects is better than not closing defects in preventing internal hernias after bariatric surgery.

• Closing defects may reduce the number of internal hernias compared to not closing them.

Background

An internal hernia is a serious problem that can happen after a type of weight-loss surgery called Roux-en-Y gastric bypass (RYGB). During this surgery, a small pouch is made from the stomach and connected directly to the small intestine. An internal hernia occurs when the small bowel goes through a hole created by the RYGB. If not detected or treated in time, it can be very dangerous. An internal hernia can cut off blood supply to part of the intestines, leading to tissue death. Emergency surgery is needed to treat this, and it often involves removing the damaged part of the intestine and reconnecting the healthy parts. Closing the defects is recommended to prevent internal hernias. However, closing defects might be associated with an increased risk of the surgical connection between small intestines becoming kinked. Currently, there is a lack of evidence that shows the benefits of defect closure.

What is internal hernia?

Definition. An internal hernia occurs when the intestines move into spaces where they do not usually go, through defects inside the abdomen.

Cause. This can happen after some obesity surgeries, which create new pathways for the intestines. These new pathways can sometimes have defects where the intestines can get stuck.

Symptoms. When the intestines get stuck, it can cause symptoms, such as pain, nausea, vomiting, and bloating.

What is Roux-en-Y gastric bypass (RYGB)?

Roux-en-Y gastric bypass surgery involves two main steps. First, the surgeon creates a small pouch at the top of the stomach. Second, the small intestine is cut and connected to this pouch, bypassing the rest of the stomach and the upper part of the small intestine. This reduces the amount of food you can eat and absorb.

What did we want to find out?

We wanted to find out whether closing defects is better than not closing them, and whether closing them is better and safer for preventing internal hernia after bariatric surgery.

What did we do?

We searched for randomised clinical trials that compared closure of defects with non-closure of defects. We compared and summarised the results of the studies and rated our confidence in the evidence, based on factors such as study methods and sizes. We investigated how successful closure of defects prevents internal hernias after bariatric surgery. In addition, we evaluated the harmful events and the length of hospital stay.

What did we find?

We found three studies, with 3010 participants, which compared closure of defects with non-closure of defects. The studies were conducted in Denmark, the United States, and Sweden.

Main results

Compared with non-closure of defects, closure of defects:

• may reduce internal hernias;

• may make little to no difference in complications after the surgery;

• may make little to no difference in death after the surgery;

• may make little to no difference in overall complications;

• may lead to a longer length of hospital stay.

What are the limitations of the evidence?

Our confidence in the results is limited because the results are from only three studies.

How up to date is this evidence?

The evidence is current to August 2024.