This procedure generates weight loss through gastric restriction (reduced stomach volume). The stomach is restricted by stapling and dividing it vertically and removing more than 85% of it. This part of the procedure is not reversible. The stomach that remains is shaped like a very slim banana with a capacity of 30-150cc, depending on the surgeon performing the procedure. The removed stomach part is responsible of secreting the hormone Ghrelin (hunger hormone) which increases the appetite. By removing this portion of the stomach the level of Ghrelin is reduced to near zero, actually causing loss of or a reduction in appetite.
The nerves to the stomach and the outlet valve (pylorus) remain intact with the idea of preserving the functions of the stomach while drastically reducing the volume. By comparison, in a Roux-en-Y gastric bypass, the stomach is divided, not removed, and the pylorus is excluded. The Roux-en-Y gastric bypass stomach can be reconnected (reversed) if necessary.
Note that there is no intestinal bypass with this procedure, only stomach reduction. The lack of an intestinal bypass avoids potentially costly, long term complications such as marginal ulcers, vitamin deficiencies and intestinal obstructions.
1) Currently, it is not known if Ghrelin levels increase again after one to two years. Patients do report that some hunger and cravings do slowly return.
2) The removed section of the stomach is actually the portion that “stretches” the most. The long vertical tube shaped stomach that remains is the portion least likely to expand over time and it creates significant resistance to volumes of food. Not only is appetite reduced, but very small amounts of food generate early and lasting satiety (fullness).
Because there is no intestinal bypass, the risk of malabsorptive complications such as vitamin deficiency and protein deficiency is minimal.
There is no risk of marginal ulcer which occurs in over 2% of Roux en Y Gastric Bypass patients.
The pylorus is preserved so dumping syndrome does not occur or is minimal.
There is no intestinal obstruction since there is no intestinal bypass.
It is relatively easy to modify to an alternative procedure should weight loss be inadequate or weight regain occur.
The limited two year and 6 year weight loss data available to date is superior to current Banding and comparable to Gastric Bypass weight loss data.
Once a patient’s BMI goes above 60kg/m2, it is increasingly difficult to safely perform a Roux-en-Y gastric bypass using the laparoscopic approach. Morbidly obese patients who undergo the laparoscopic approach do better overall in their recovery, while minimizing pain and wound complications, when compared to patients who undergo large, open incisions for surgery. In addition, the Roux-en-Y gastric bypass tends to yield inadequate weight loss for patients with a BMI greater than 55kg/m2. The solution was to ‘stage’ the procedure for the high BMI patients.
Sleeve Gastrectomy is a reasonable solution to this problem. It can usually be done laparoscopically even in patients weighing over 250 Kg. The stomach restriction that occurs allows these patients to lose more than 70 Kg. This dramatic weight loss allows significant improvement in health and resolution of associated medical problems such as diabetes and sleep apnea, and therefore effectively “downstages” a patient to a lower risk group. Once the patients BMI is lower (35-40) they can return to the operating room for the “second stage” of the procedure, which can either be the Roux–en-Y gastric bypass or even a Lap-Band. Current, but limited, data for this ‘two stage’ approach indicate adequate weight loss and fewer complications.
The Sleeve Gastrectomy has proven to be quite safe and quite effective for individuals with a BMI in lower ranges.
Low BMI individuals who should consider this procedure include:
- Those who are concerned about the potential long term side effects of an intestinal bypass such as intestinal obstruction, ulcers, anemia, osteoporosis, protein deficiency and vitamin deficiency.
- Those who are considering a Lap-Band but are concerned about a foreign body or worried about frequent adjustments or finding a band adjustment physician.
- Those who have other medical problems that prevent them from having weight loss surgery such as anemia, Crohn’s disease, extensive prior surgery, severe asthma requiring frequent steroid use, and other complex medical conditions.
- People who need to take anti-inflammatory medications may also want to consider the Sleeve Gastrectomy. Unlike the gastric bypass, where these medications are associated with a very high incidence of ulcer formation. Also, Lap-Band patients are at higher risks for complications from NSAID use.
All surgical weight loss procedures have certain risks, complications and benefits. The ultimate result from weight loss surgery is dependent on the patients risk, how much education they receive from their surgeon, commitment to diet, establishing an exercise routine and the surgeons experience. As Dr. Jamieson summarized in 1993, “Given good motivation, a good operation technique and good education, patients can achieve weight loss comparable to that from more invasive procedures.”