Gastric Sleeve Operations Are Not All the Same

patient outcomes vary between gastric sleeve surgeons at bariatric surgery centers of excellence

Most operations are fairly standardized, meaning that all surgeons (given adequate training and experience) do pretty much the same thing when they perform the operations. Some operations – think cosmetic operations, for example – are not standardized, and therefore different surgeons do different things when they do the operations.

The importance of surgeon technique variation is that it results in patient outcomes variation. Again think cosmetic surgery – different surgeons achieve different outcomes due to differences in surgical technique.

What about the gastric sleeve operation? The gastric sleeve operation is not a standardized operation – different gastric sleeve surgeons do the operation in different ways.

The questions I will address in this post:

  • How much variation in surgical technique is there between different surgeons?
  • How much does variation in surgical technique affect patient outcomes?
  • Why is the gastric sleeve operation not a standardized operation?

How Much Difference in Technique Is There Between Surgeons?

It is obvious to me, as a weight loss surgeon, that there is substantial variation in how different gastric sleeve surgeons do the gastric sleeve operation. But what is the proof for this? Variation in surgeon technique is not something that gets a lot of research interest (although it should!), but there are a few studies that we can look to for proof.

The best studies about variation in surgical technique are studies that involve reviewing videos of operations done by different surgeons. Several excellent, video-based studies have been published by a research group from the University of Michigan.

One of these studies, published in 2017, entitled “Far from Standardized: Using Surgical Videos to Identify Variation in Technique for Laparoscopic Sleeve Gastrectomy,” involved reviewing surgery videos from 20 different gastric sleeve surgeons. What they found was that gastric sleeve surgical technique was not uniform between the surgeons. They found variation in (1) hiatal hernia repair technique, (2) stapling technique, and (3) post-transection staple line management. Those 3 categories, incidentally, comprise basically the whole gastric sleeve operation.

Even more illuminating are the comments made by one of the study authors at the 2017 ASMBS (American Society for Metabolic and Bariatric Surgery) Annual Meeting. The author, in a presentation about this study, stated that before he analyzed the videos, he thought, “how different can the operations really be?” His conclusion after analyzing the videos – “remarkably different.” He explained that he saw a “vast amount of variation” in surgical technique between surgeons.

Does Variation in Surgical Technique Matter?

It is also obvious to me, as a weight loss surgeon, that variation in surgical technique has a major impact on patient outcomes. But again, for proof, we need to look at the published gastric sleeve literature.

One excellent study, published in 2017, entitled “ Variation in Outcomes at Bariatric Surgery Centers of Excellence,” reported that the rate of serious complications within 1 month after weight loss surgery varied 17-fold (not a typo – 17-fold!) across 165 accredited bariatric surgery center of excellence programs nationwide, from 0.6% to 10.3%. The authors attributed this variation in complication rates to the fact that there were different surgeons, with different skill levels, and different ways of doing the operations, at the different centers.

Similarly, weight loss results after the sleeve gastrectomy operation have been reported to be anywhere from 40-50% average excess weight loss, to 70-80% average excess weight loss, depending on surgeon/program.* Surgeon gastric sleeve leak rates vary from 0 in >500 operations, to 1 in 25 operations – that is a greater than 20-fold difference between individual surgeons!*
Gastric sleeve outcomes vary between surgeons

Some of this variation in outcomes between surgeons, particularly for weight loss results, is due to differences in patient care (education, follow-up, support) between different surgeons and programs, but it is hard to attribute differences in complication rates, particularly for complications early after surgery, to be due to anything other than differences in how the operations are being performed.

To read more about outcomes variation between individual surgeons and programs, see the following:
Gastric sleeve outcomes vary by surgeon
Variation in outcomes at Centers of Excellence
Gastric sleeve weight loss
Gastric sleeve complications

Why Is the Gastric Sleeve Operation Not Standardized?

As described above, many operations are standardized. This means there is consensus on how the operation should be done to achieve the desired outcome. In general, this is true for operations that involve removing something (gallbladder, uterus, tumor, etc.), or repairing something (blockage in an artery, hernia, broken bone, etc.).

For operations that involve re-forming something, there is often not consensus on how the operations should be done to achieve the desired outcome.

Consider cosmetic surgery. The goal in cosmetic surgery is to re-form a body area, such as the abdomen in a tummy tuck operation, or the face in a facelift operation, to achieve a better cosmetic appearance.

The cosmetic outcome achieved with a tummy tuck or face lift operation is dependent upon countless, small, subjective, hard-to-reproduce details of surgical technique – where you cut, how you suture, the degree and direction of traction you put on various tissues when you cut and suture, etc. There is agreement on how the operations should be done in terms of the general steps, but there is not agreement on all the subtle surgical technique details that ultimately determine the quality of the outcome.

Outcomes are highly variable between different plastic surgeons. This really speaks to the fact that it is hard to get all the subtleties of surgical technique right to achieve a great outcome. It takes a long time and significant effort for individual surgeons to learn what combination of the countless, small, subtle surgical technique details results in the best outcomes. This is the art of plastic surgery – knowing what combination of surgical technique details will result in a great cosmetic outcome.

Gastric sleeve surgery is similar. It is basically plastic surgery on the stomach to achieve great weight loss, a good experience of eating, and no complications. Similar to a tummy tuck operation, the ultimate form (and function) of the sleeve stomach will depend on the many small details of how each step of the operation is done – where you cut, the direction you cut, how you suture, how you apply traction to the stomach when you cut and suture, etc.

Similar to cosmetic surgery operations, there is agreement on the general steps of the gastric sleeve operation, but there is not agreement on the countless, small, subjective, hard-to-reproduce details of surgical technique. There are too many details that can vary in too many ways to be able to define the “best way” to do the operation. Because there is no accepted “best way,” gastric sleeve surgeons develop and hone their individual surgical technique over time.

There are 2 other factors, in my experience, in addition to lack of gastric sleeve standardization, that result in outcomes variation between surgeons:

  • Differences in surgeon skill and ability
  • Differences in surgeon priorities

Surgeon Skill and Ability

Different bariatric surgeons have different skill and ability levels, and this has an effect on surgical technique and patient outcomes, like it does for all operations. But how much?

One study, published in the New England Journal of Medicine, entitled “Surgical Skill and Complication Rates After Bariatric Surgery,” analyzed surgery videos from different bariatric surgeons, rated surgeon skill level, and correlated surgeon skill and ability with complications after surgery. What they found was that the skill level of bariatric surgeons “varied widely”, and greater surgeon skill was associated with fewer postoperative complications and lower rates of reoperation, readmission, and visits to the emergency room.*

Surgeon Priorities

Differences in surgeon priorities, in my experience, is a major reason for why surgical technique and patient outcomes vary so much between individual surgeons and programs.

What do gastric sleeve surgeons prioritize? The choices are themselves, patients, or some combination of the two. Prioritizing patients means prioritizing quality of surgery, patient care (education, follow-up, support), and patient outcomes. Prioritizing themselves means prioritizing fast operations and minimal patient care. These are two very different paths to travel down.

Because there is not a lot of focus on surgeon outcomes statistics, surgeons have surprisingly little accountability for the quality of work they do. This lack of accountability for outcomes frees surgeons to be able to prioritize themselves higher than they would be able to do if there was more accountability for outcomes.

When surgeons prioritize themselves they prioritize speed of surgery and number of operations, and they scimp on patient care (education, follow-up, support). Surgery is the primary income generator for bariatric surgeons, so the more surgeries done, the more money made. A ½ hour sleeve gastrectomy operation, after all, is 4x more profitable than a 2 hour sleeve gastrectomy operation!

Surgeons are a competitive group, and they like to brag about how great they are. The subjects that gastric sleeve surgeons brag about are telling. Do they brag about their outcomes? In my experience, almost never. What they do brag about is how fast they are. Even, ironically, the surgeon reviewer who conducted the site visit for my hospital’s Center of Excellence certification, the goal of which is to improve outcomes, told stories not about his patient outcomes, but about his team’s incredible speed in the operating room.

It takes about 2 hours, on average, for me to do a straightforward gastric sleeve operation well, and achieve excellent outcomes statistics.* I do at most 3 operations in a day. Many surgeons do many more operations per day. Some do 10-12 operations per day. It is obvious to me what these surgeons are prioritizing, and it is not quality of surgery and patient outcomes!
How I do the gastric sleeve operation
Watch a gastric sleeve operation with narration


Gastric sleeve operations are not all the same. There is a “vast amount of variation” in surgical technique between individual surgeons, and this has a major impact on patient outcomes. Because of this, choice of gastric sleeve surgeon is a very important decision.

Read How to Choose a Gastric Sleeve Surgeon.

Read more about Dr. Oliak and his Orange County weight loss surgery program.

* Individual outcomes vary after weight loss surgery. Outcomes vary between different surgeons, and outcomes vary between different patients. Past performance is no guarantee of future results.

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