Chrysalis Clinic Health
Patient Experience
HOME
TEAM
CONTACT US
  BMI
  calculator
Weight (kg)
Height (cm)

purely restrictive operations

Introduction

Purely restrictive operations are all based on the premise that reducing the volume of food that can enter the gastrointestinal tract will result in significant weight loss. The simplest method of reducing food intake, although totally impractical as a long-term solution, is wiring the jaws together, as is done by maxillofacial surgeons to allow healing of mandibular fractures. Apart from being impractical, it is not an effective weight-reducing solution. This is probably because it in no way addresses the issues of appetite, satiation and satiety.

In the era of open bariatric surgery, the restrictive operation that stood the test of time as a reasonably effective bariatric operation was the vertical banded gastroplasty (VBG).

The VBG has been replaced in the laparoscopic era by the laparoscopic adjustable gastric band (LAGB) operation.
A new addition to the menu of restrictive operations is the sleeve gastrectomy (SG).


Laparoscopic Adjustable Gastric Band (LAGB)

Technically, this is the easiest and simplest bariatric operation. The early morbidity and mortality rates are, therefore lower than for other operations, mainly because this operation does not involve any removal of any part of the gastrointestinal tract (GIT) and no anastomoses (joins between different parts of the GIT). It involves placing around the proximal (upper) end of the stomach a silastic band that has an embedded inflatable cuff. The cuff is connected by a silastic tube to a port (a small plastic chamber) that is placed on the anterior (front) surface of the anterior abdominal muscle layer, under the skin and subcutaneous fat, and is accessible by needle through the skin and through a rubbery silastic “roof” to the chamber. After surgically placing the band, its cuff is left deflated for a few weeks. When things have settled a few weeks after the surgery, small volumes of liquid are injected into the port to inflate the cuff of the band, thus narrowing the inlet to the stomach. Inflation of the cuff should be done under fluoroscopic (X-ray) screening, using radiological contrast medium to inject into the port while the patient swallows some barium.


Sleeve Gastrectomy (SG)

In this operation the reservoir capacity of the stomach is greatly reduced by resecting (surgically removing) the greater curve aspect of the stomach. This is achieved by first inserting a 32-36Fr bougie (cylinder) via the mouth, through the oesophagus, into the stomach and through the pylorus with the bougie tight against the lesser curve. Then, the stapling device is placed along the left side of the bougie and fired serially from the distal (lower) end of the stomach to the upper end immediately to the left of the oesophago-gastric junction. This converts the large bag-like stomach into a narrow, banana-shaped tube between the oesophagus and duodenum. This operation is not as simple as the lapband, but is a much simpler operation than the gastric bypass or malabsorptive operations. However there is a long staple line that carries the risks of leakage and bleeding. The continuity of the GIT is not interrupted, so there should not be any risk of any nutritional deficiencies except, possibly, Vitamin B12 which has to bind to a co-factor called intrinsic factor, secreted by the gastric fundus, which is removed in this operation.


Advantages and Disadvantages

The Band
The main advantages of the band are the relative simplicity of the surgery and the low risk of early post-op complications. A questionable advantage is its adjustability. In the longer term several problems can develop: being a “foreign body” there is an ever present risk of infection; the band can erode into the stomach or it can migrate, slipping up or down; the cuff can burst; the tubing can disconnect from the port; the port can tip over so that the silicone-rubber roof cannot be penetrated to inject fluid; the port can erode through the skin. The effectiveness as a weight loss operation is considerably less than the gastric bypass and malabsorptive operations. On average, maximum weight loss achieved is about 50% of excess weight, compared to 75-85% with the more complex operations. Furthermore, the weight loss is not sustained as well as the other operations so that after reaching a nadir (lowest point) at about 18 months, there tends to be significant weight regain. There is no predisposition to any nutritional deficiencies, but if the patient has any tendency to gastro-oesophageal reflux, this will be greatly aggravated by placing a band distal to (beneath) an incompetent lower oesophageal sphincter. Furthermore, with an incompetent lower oesophageal sphincter the oesophagus may dilate to replace the reservoir function of the stomach (i.e. to accommodate the backflow of food from the stomach). This may result in unsatisfactory weight loss and possible overflow of food into the lungs, which can result in serious chest problems. Weight loss is said to be more effective with the band in people who tend to be binge-eaters and conversely, less effective in sweet-eaters.

The Sleeve
Compared to the other operations the sleeve is also a relatively simple and quick operation. It can be used as a bariatric operation in its own right or as a first stage operation that can be converted later to a gastric bypass or bilio-pancreatic diversion (BPD). Provided the tube is made narrow-enough, this is a very effective restrictive operation and, by removing the grehlin-producing gastric fundus it also has a significant suppressive effect on appetite. Short-term follow-up studies show that the average reduction of excess weight is about 60%. Because it has only recently been utilized as a bariatric operation in its own right, data on its effectiveness in the longer term is still lacking. Because a large part of the acid-producing stomach has been removed, there is less risk of aggravating reflux oesophagitis.