Mini-Gastric Bypass vs. RNY Gastric Bypass

Written by Bryee Shepard, MS, RD and medically reviewed by Dr. Stephen Boyce, MD

With many advances in the field of bariatric surgery, new surgical methods arise regularly to improve the efficacy and outcomes of the various procedures. The mini-gastric bypass is an example of such advances.

Here are some quick facts about the mini-gastric bypass to get us started. The procedure:

With all that being said, what exactly is the mini-gastric bypass? Let’s jump into all there is to know about the procedure.

What is a mini-gastric bypass?

A mini-gastric bypass, also known as a single-anastomosis gastric bypass, is a weight loss surgery procedure that has been established as a safe alternative surgical method.

The surgery is considered minimally invasive because it is performed laparoscopically in which a small incision is created and a special camera is inserted through the incision. The camera then transmits images of the abdominal cavity to video monitors that the surgeon uses for the procedure.

Mini gastric bypass anatomy before and after

During a mini-gastric bypass procedure, the top part of the stomach is stapled off to form a thin tube that becomes the new stomach pouch. This pouch then bypasses the first part of the small intestine known as the duodenum and is attached just below. The remaining part of the stomach and small intestine that was bypassed remains in the body but is no longer functioning in the digestion process.

Mini-gastric bypass VS traditional gastric bypass

The traditional gastric bypass, also called the Roux-en-Y (or RNY) procedure serves as the gold standard of bariatric surgery, and that which the mini-gastric bypass originated from. The difference between the two surgeries lies within the procedure itself.

Gastric bypass vs mini gastric bypass

The traditional Roux-en-Y procedure reduces the stomach size to hold about one ounce of food or liquids. The small intestine is then divided to separate the upper and lower parts, known as the duodenum and the jejunum. The new stomach pouch is attached to the lower portion of the small intestine, or jejunum, while the upper portion of the small intestine, or duodenum, is connected further down the small intestine.

That is, two new connections are made. One from the new stomach to the lower small intestine, and another from the upper small intestine to the lower small intestine.

Like the Roux-en-Y, the mini-gastric bypass reduces the stomach. However, the new stomach pouch is somewhat larger, holding a volume of two to five ounces. Rather than dividing the small intestine, the new stomach pouch is attached directly to the jejunum or lower portion of the small intestine. Therefore, only one new connection is made, thus simplifying the gastric bypass procedure.

Let’s take a deeper look at the similarities and differences between the mini-gastric bypass and the Roux-en-Y. When compared to the traditional Roux-en-Y gastric bypass, the mini-gastric bypass offers:

  • A shorter operative time
  • Fewer temporary or permanent disabilities that occur during the procedure
  • Slightly higher long term weight loss rates
  • Similar outcomes in resolving metabolic syndrome
  • A simpler method to obtain the same if not better results
advantages of the mini gastric bypass

It’s clear that the mini-gastric bypass procedure is a safe and effective contender in the bariatric surgery field. Let’s dive deeper into how much weight you can expect to lose after this procedure and how it compares to other popular weight-loss surgeries.

Weight loss after mini-gastric bypass

How much weight will you lose after undergoing your mini-gastric bypass surgery? To accurately make a determination, we must turn to the research. In most clinical research studies, weight loss comparisons are made by assessing excess body weight lost.

Quick tangent: Excess body weight is basically your current body weight minus your ideal body weight. This leaves us with the extra weight, beyond our ideal body weight, that could be lost safely. For a more detailed understanding of excess body weight, check out this article.

how much excess weight you can lose

In many studies, the mini-gastric bypass outperforms other bariatric surgeries in long-term weight loss. Let’s compare the two most performed bariatric surgeries, Roux-en-Y gastric bypass and vertical sleeve gastrectomy (VSL), or gastric sleeve, with the mini-gastric bypass.

Excess Body Weight Lost1 Year Post Op5 Years Post Op
Mini-Gastric Bypass69%73%
Roux-en-y Gastric Bypass74%60%
Gastric Sleeve (VSG)60%49%

*Excess body weight loss values for mini gastric bypass vary based on reported data

It is pretty clear that the mini-gastric bypass results in the most weight loss long term.

Why isn’t the mini-gastric bypass performed more?

The mini-gastric bypass appears to be a slightly safer bariatric procedure having improved weight loss outcomes. If this is the case, why isn’t it the gold standard in bariatric surgeries?

There are a few reasons:

reasons the mini gastric bypass isn't used much

Although these risks are significant, they are less common. It is important to discuss them with your physician prior to making a determination on your bariatric surgery choice.

Additionally, there is the barrier of cost.

Cost of the mini-gastric bypass procedure

The mini-gastric bypass can cost anywhere from $16,000 – $22,000 depending on the state and location of the procedure as well as the physician and hospital in which it is performed. This is significantly less than the average Roux-en-Y bypass which can cost, on average, $18,000 – $35,000. However, much of this cost can be offset with the help of insurance.

mini gastric bypass vs. gastric bypass cost

Unlike the traditional Roux-en-Y gastric bypass, most insurance companies will currently not cover the mini-gastric bypass surgery. Coupled with the fact that few physicians perform the surgery, the lack of insurance coverage makes access to the procedure much more challenging for many.

Who should have the mini-gastric bypass?

Because the mini-gastric bypass is not yet performed as routinely as the traditional gastric bypass, the guidelines for who qualifies for the procedure are not as clear. Most often, an individual will qualify for the procedure if they qualify for the Roux-en-y bypass.

To qualify, the candidate should have a Body Mass Index (BMI) over 40. This is considered severe obesity. Surgeons will often perform the procedure on patients with a BMI above 35 if they have other comorbidities such as type 2 diabetes or high blood pressure.

eligibility for bariatric surgery

To determine if the mini-gastric bypass is right for you, it is important that you talk to your physician about the risks and benefits associated with the procedure in relation to your specific weight loss journey.

Regardless of your surgical choice, check out BariLife’s wide range of products to satisfy your every craving and nutritional needs both before and after surgery.

In summary

As you have learned, the mini-gastric bypass can be thought of as a simplified version of the traditional Roux-en-y gastric bypass. With a shortened surgical time and decreased surgical complications, it is a promising option for some. However, because of certain risks such as severe biliary reflux as well as the lack of insurance coverage, the mini-gastric bypass is not for everyone.

As always, it is recommended to foster a trusting relationship with your physician in order to determine the best procedure for you or your loved one.

Share

More Bariatric Articles

Gastric Sleeve vs. Lap Band

Obesity is associated with the leading causes of death worldwide, including diabetes, heart disease, stroke, and some types of cancer. Weight-loss surgery can be a great option for those struggling with morbid obesity and experience obesity-related complications. Weight-loss surgery, including both gastric sleeve and lap band operations, achieves weight loss in patients by altering the […]

What to expect first 3 months after gastric sleeve

If you are planning to have the gastric sleeve procedure it is important to be aware of the necessary lifestyle modifications and adjustments that you are required to make following surgery. Knowing what to expect after the procedure can help you to optimize your recovery and weight loss. This article will provide an inside look […]


What are your tips and tricks to post-bariatric success?

Share your thoughts or questions in the comments below – we want to hear from you!

One comment

  1. Any weight loss surgery is simply a tool to get us moving in the right direction for weight loss; However, if we do not change our mindset and relationship with food, we will not have any sort of long term success. I had the RNY back in 2007. I lost 135 pounds. In the 13 1/2 years since I have managed to stay within my healthy BMI range but have gained back 25 pounds. I found this website with the 2 week post op bundle and am starting it today to get my portion control back under control along with trying to eliminate cravings for sweets and bad carbs.

Submit a Comment

Your email address will not be published. Required fields are marked *

Share

×