**3.5 Outcome**

The success of LSG in weight loss depends on several factors. Some are related to the technique conducted, like the size of the bougie used and the distance from the pylorus where the first stapler is applied [41]. Restricting oral intake is not only the reason for weight loss, but also LSG affects the hormones of interest involved in weight and hunger. The ghrelin level drops significantly postoperatively by removing the fundus, and the peptide YY (PYY) gets considerable elevation after the surgery. This observation probably explains the rapid satiety and hunger reduction during the early years after LSG [42]. Following dietary instructions and avoiding a sedentary lifestyle are key components of success [43]. As long as the procedure is done properly, predictors of weight regain/insufficient weight loss following LSG can be related mainly to dietary misbehavior and nonadherence to instructions [44]. Since restriction has failed in patients with WR/IWL following LSG, a rational strategy is adding a malabsorptive element in the surgical management. The classic revision of LSG is to convert to RYGB, but the OAGB seems to be a strong contender for two main reasons (**Table 3**). First, OAGB showed a comparative efficacy to RYGB as a rescue procedure, with less operative time and fewer complications [49]. Second, more options for managing weight recidivism can be achieved by adding a procedure before RYGB, which is the OAGB. In case OAGB fails, it can be converted smoothly to RYGB.

There are critiques mentioned in the literature expressing the disapproval of OAGB in some aspects. One of these remarks is the fear of bile reflux and the subsequent continuous esophageal irritation, which is worrisome. This is possible if the gastric pouch is short, increasing the chance of bile backflow to the stomach and ultimately in the esophagus. Keeping the gastric pouch long is critical to prevent the feared bile reflux, and being liberal in using "alignment stitches" or the so called "anti-reflux stitches" to prevent kinks or twists are critical elements in the procedure (**Figure 10**) [50, 51]. After improving the technique of the OAGB procedure, the rate of bile reflux following OAGB is reported to be around 0.7–2% [52, 53].


#### **Table 3.**

*Outcome following revision of sleeve gastrectomy to one anastomosis gastric bypass.*

A large portion of the bariatric community classifies OAGB as a malabsorptive procedure. Malnutrition became an issue because the bypassed BPL can be as long as 300 cm in some practices. Reports showed severe nutritional deficiencies, hypoalbuminemia, and liver failure [54, 55]. In a survey conducted targeting IFSO members, all revisions due to malnutrition occurred when the BPL was 200 cm or more [56]. Because of OAGB's simplicity, the length of BPL is the only possible reason for this outcome. It seems that elongating the BPL is not beneficial from a weight-loss standpoint and endangers the patient with malnutrition and its dreadful consequences. Recently, it has been highly recommended not to exceed 180 cm of BPL length in order to prevent malnutrition, and at the same time, this limit will not compromise weight loss [55, 57].

The rate of reported GERD development after LSG ranged from 7.8 to 20%. It could be the consequence of fibers/ligaments division near the gastroesophageal junction, which alters and nullifies the angle of his features in protecting from reflux. Other factors include increased pressure because of the lumen narrowing or missing a hiatal hernia [58]. Unfortunately, when reflux develops after LSG due to a hiatal hernia, simply repairing the hiatal hernia showed disappointing results [59]. The applicability of OAGB in the treatment of reflux is a valid option in certain situations. If there is no severe reflux or Barret's esophagus on endoscopy, OAGB is a suitable option [60]. Clear communication with the patient about the possible recurrence of manageable reflux postoperatively is necessary.

### **4. Revision of Roux-en-Y gastric bypass**

Since several decades ago, laparoscopic Roux-en-Y gastric bypass (RYGB) is still a valuable tool in the bariatric surgeon's arsenal. It has a unique configuration where it implements a restrictive mechanism by dividing the stomach and forming a small gastric pouch. Secondly, RYGB involves bypassing some of the small bowels by constructing the Roux limb/alimentary limb delivering the food and a biliopancreatic limb delivering the pancreaticobiliary juices and meeting at the start of the common channel where most of the absorption takes place. (Wolfe) The length of each limb is variable, and there is no clear consensus about the perfect measurements. However, what is agreed on is the efficacy of RYGB in weight reduction by several other

#### *Revisional Bariatric Surgery DOI: http://dx.doi.org/10.5772/intechopen.106019*

mechanisms, including changes in eating behavior, the favorable elevation of gut hormones (GLP1 and PPY), and likely beneficial changes in energy expenditure [61]. The efficacy of RYGB was pronounced in the literature. With effective and sustainable weight loss and resolution of comorbidities, it is regarded as one of the most effective procedures to combat obesity and obesity-related diseases [2, 62].

### **4.1 Indication of revision**

Despite the effectiveness of RYGB, sadly, it is not immune to the possibility of revisions. The most typical indication of revision after RYGB is the weight regain. We cannot stress enough the importance of interviewing the patient and evaluating one of the most critical factors contributing to weight-regain: dietary habits and lifestyle. Other possible anatomical causes of weight regain need further evaluation. Additional indications for revisions are bile reflux, which can happen in the case of a short alimentary limb [63]. Patients can complain of GERD symptoms post-RYGB, and the presence of a hiatal hernia; a large gastric pouch producing acid can explain this presentation.

#### **4.2 Preoperative workup**

Binge eating and loss of self-control can be significant contributing factors to weight regain following bariatric surgery. This issue can be ameliorated with a behavioral therapist and a qualified dietician [64]. Other aspects contributing to weight regain that are related to surgical factors include the diameter of GJ anastomosis, a gastro-gastric (GG) fistula, or a dilated gastric pouch [65–67]. It is an excellent practice to start with an upper contrast study to evaluate the aforementioned anatomical features. If a suspicion of wide GJ anastomosis or a GG fistula is present, an EGD is recommended [68]. Preoperative nutritional assessment and vitamin level could be valuable (**Figure 14**).

#### **4.3 The operation**

The procedure starts with proper and secure patient positioning. Access to the abdomen is achieved using a visiport at 5 cm above and to the left of the umbilicus. Other ports and liver retractors are inserted in a controlled manner. Counting the

#### **Figure 14.** *Suggested pathway decision for revision of Roux-en-Y gastric bypass.*

**Figure 15.** *Constructing a side-to-side jejunojejunostomy.*

whole bowel at the beginning of the procedure and writing down the measurements is very helpful in formulating a plan. In case of weight regain, our practice dictates shortening the common channel to not less than five meters. The biliary limb is the one getting elongated. The jejunojejunostomy (JJ) will be divided at the distal end of the alimentary limb and brought down to the marked point of the new anastomosis. Enterotomies are made on the antimesenteric side, and a side-to-side anastomosis is made (**Figure 15**). Closure of the enterotomies is achieved using a double monofilament layer. The mesenteric defects need to be sought out and closed.

Resizing the gastric pouch when applicable is advantageous. In case of extensive adhesions near the gastrojejunostomy, we tend to avoid resizing the pouch if dissection is needed, which might jeopardize blood supply to the GJ anastomosis. It

**Figure 17.** *A nonadjustable band is applied and sutured to the gastric pouch.*

is essential to investigate the presence of hiatal hernia intra-operatively even if the preoperative scope did not show any signs of hiatal hernia. If present, the release of adhesions and mobilization of a 2–3 cm intrabdominal esophagus is needed. The hernia is closed using an anterior and posterior monofilament sutures. If the common channel is short and does not allow for JJ distalization, applying a nonadjustable restrictive ring might be applicable. Careful dissection proximal to the GJ anastomosis is needed, and it should be snugly applied with no constriction (**Figures 16** and **17**).
