Most modern bariatric operations are now based upon the performance of a gastric restriction procedure, responsible for the short-term weight loss, and a gastrointestinal bypass, which should warrant the maintenance of weight loss over time. But due to concerns of nutritional deficiencies, the more malabsorptive operations have declined in numbers with the restrictive varieties becoming more popular [1]. But there still remains a definite role for more malabsorption even as we try to become more conservative in the choice of procedure. This is applicable, more so in super obese patients and in patients with a severe metabolic syndrome [2].

Nicola Scopinaro is credited with describing the original bilio-pancreatic diversion (BPD) [3]. His procedure was a modification of the jejuno-ileal bypass (JIB) (anastomoses of the proximal jejunum to the distal ileum without any excision resulting in a long blind loop). He performed a distal gastrectomy anastomosing to a 250 cm roux limb and a short common channel of 50 cm (distal gastrectomy with exclusion of the first half of the small bowel with a gastro-ileostomy with reconnection of the bypassed bowel). This procedure thus abandoned the long blind loop of a JIB but maintained the malabsorption. However this was associated with a relatively high rate of dumping and marginal ulcers.

The stand-alone duodenal switch procedure (without bypass) was described by DeMeester in the 1980s to treat bile-reflux gastritis as a roux-en-Y duodenojejunostomy [4]. The modified duodenal switch (DS) was later introduced as a modification of Scopinaros BPD, first described by Marceau in 1993 which combined the Scopinaro procedure and the DeMeester’s DS (vertical gastrectomy with exclusion of the first half of the small bowel with a duodeno-ileostomy with reconnection of the bypassed bowel) [5]. A vertical gastrectomy was performed rather than a distal gastrectomy anastomosing the roux limb to the stapled proximal duodenum thus reducing the parietal cell mass, eliminating the distensible fundus, preserving the pylorus valve and the duodenum. In 1998, Hess and Hess further modified this with the diversion of the duodenum, leading to the modern day biliopancreatic diversion with duodenal switch (BPD/DS) [6]. Gagner et al. described the first laparoscopic BPD/DS, which represents the current standard technique widely followed [7].

Laparoscopic BPD/DS is the most commonly performed malabsorptive operation worldwide [1]. But different modifications have been made to this to make it more technically simpler and also to reduce the extent of malabsorption. This includes the Sleeve gastrectomy with duodenal jejunal bypass (Sleeve DJB) or Sleeve gastrectomy with loop DJB and Single anastomosis duodeno-ileal bypass (SADI-S), the latter two with advantage of a single anastomosis [8–10]. Although they have been described as separate procedures in literature, for better understanding we refer to this as variants of the more standardized BPD/DS.

In this chapter we aim to describe the standard steps in the technical creation of BPD/DS with necessary variations of the variant techniques. The different variants are named according to the length of limb and/or method of reconstruction (roux-en-Y or loop anastomosis). BPD/DS and SADI-S have a short common limb, Sleeve DJB and Sleeve with loop DJB have a long common limb for avoiding malnutrition. BPD/DS and Sleeve DJB are provided with roux-en-Y reconstruction, SADI-S and loop DJB are with loop (Billroth-II) reconstruction to avoid technical difficulty of a roux-en-Y reconstruction. The procedures are routinely done laparoscopically, but in difficult situations, hand assisted techniques have also been described [11].