We shall now examine the technical
procedures in details. They have been initially designed for an open approach
(laparotomy), but as the other bariatric operations, they are now routinely
performed through the mini-invasive laparoscopic approach ("key-holes
operations"). There are two major stages. The first one creates a degree of
gastric restriction: removal of about half of the stomach (horizontal
gastrectomy), or vertically: "sleeve gastrectomy " (see previous newsletter).
The sleeve gastrectomy has the advantage to maintain the pylorus function,
thus a better emptying of the stomach and a better food tolerance. Moreover, we
have seen that it could be made on its own, as a first step operation for a
fragile patient, or if a previous procedure has failed (such as lap-banding).
The second stage is the short-cut, that brings the small intestine straight
to the stomach with a running suture (or anastomosis), which makes it possible
to bypass the biliary and pancreatic output from the main alimentary tract. This
output will join the main tract only after a long distance (more than 2m) so
that the portion of bowell that is actually in contact with these secretions
(that is called the "common limb") is very short (less than 1 m). The place of
the anastomosis is either the stomach (typical bilio-pancreatic bypass) or the
duodenum if it is maintained (i.e. the "duodenal switch": see figure).
Some variations have been described in terms of intestinal limbs length. There
is another more complicated variation: the gastro-jejunal bypass has
typically a different anatomy (see previous chapters). Yet some surgeons deem it
insufficient for some of their patients and propose a "long-limb gastric
bypass", with no actual bilio-pancreatic short-cut, but a very similar effect
because the "alimentary limb" is highly increased beyond the usual 1m50... The
current trend is to propose to some obese patients (those with a very high BMI)
radical operations that have potential severe long-term consequences:
deficiencies (vitamines, proteins, etc.) due to the malabsortion. They require a
close monitoring but offer impressive long-tem results, and the best weight-loss
in the bariatric field.
