Laparoscopic One Anastomosis Gastric Bypass Versus Laparoscopic One Anastomosis Gastric Bypass with Braun Anastomosis: What's Better?

Abstract

Background and Aims:

Although laparoscopic one anastomosis gastric bypass (LOAGB) is a promising bariatric procedure, a large number of surgeons have strong objections mainly because of risk of bile reflux, marginal ulceration, malnutrition, and long-term risk of gastric and esophageal cancer. Lateral enteroenterostomy placed distally to a gastrojejunal anastomosis shows efficacy in preventing bile reflux after gastric resection and gastrojejunal anastomosis, but at present its efficacy in a bariatric surgery context has not been evaluated.

Patients and Methods:

From January 2013 to December 2018, 100 patients have been admitted to our department to be treated by performing LOAGB. Patients have been divided into two groups on the basis of the indications to this surgical procedure; Group A: presence of de novo gastroesophageal reflux disease (GERD) or severe esophagitis after laparoscopic sleeve gastrectomy, with or without weight regain; Group B: LOAGB as primary procedure. Another group of 30 patients (Group C) underwent LOAGB with Braun anastomosis as primary bariatric surgical procedure for morbid obesity. We have conducted a retrospective analysis of the surgical outcomes in terms of perioperative mortality, short-, mid-, and long-term postoperative complications and weight loss.

Results:

Group A: 50 patients; incidence of postoperative GERD, esophagitis, or esophageal ulcers was 26% (13 cases). All these patients have been successfully treated by performing Braun anastomosis. Group B: 20 patients; incidence of de novo reflux was 25% (5 cases); Braun anastomosis was performed with complete resolution of signs and symptoms in all cases. Group C: 30 patients; no cases of de novo reflux, esophagitis, or anastomotic ulcers occurred.

Conclusion:

Braun anastomosis seems to be a useful surgical tool to prevent the onset of de novo reflux, esophagitis, and anastomotic ulcers.

Background

Laparoscopic one anastomosis gastric bypass (LOAGB) is a promising bariatric procedure; several advantages such as technical simplicity, shorter learning curve, ease of revision and reversal, noninferior weight loss, and comorbidity resolution lead to advocate a wider adoption of this procedure; despite these encouraging aspects, a large number of surgeons have strong objections to this procedure and do not perform it. The risks of symptomatic bile reflux, marginal ulceration, severe malnutrition, and long-term risk of gastric and esophageal cancers are some of the commonly voiced concerns.¹

Rutledge published his initial experience with 1274 one anastomosis gastric bypasses in 2001.² Over the ensuing years, a number of surgeons have published extensive experience with this operation in both primary and revisional settings.^3–11

Lateral enteroenterostomy placed distally to a gastrojejunal anastomosis (the so called Braun anastomosis) demonstrated efficacy in preventing bile reflux and delayed gastric emptying after gastric resection^12,13; anyway, at present, very few experiences in literature evaluated the role of this anastomosis in a bariatric surgery context.

Materials and Methods

From January 2013 to December 2018, 100 patients have been admitted to our department to be surgically treated by performing LOAGB.

Patients have been divided into two groups on the basis of the indications to this surgical procedure:

- Group A: presence of de novo gastroesophageal reflux disease (GERD) or severe esophagitis after laparoscopic sleeve gastrectomy (LSG), with or without weight regain.

- Group B: LOAGB AS primary bariatric surgical procedure choice for the treatment of morbid obesity

Another group of 30 patients (Group C) underwent laparoscopic one anastomosis gastric bypass with Braun anastomosis (LOAGBB) as primary bariatric surgical procedure for morbid obesity.

All patients have been evaluated preoperatively with upper GI endoscopy and upper gastrointestinal (GI) X-Rays to detect the presence of GERD or esophagitis signs.

We have conducted a retrospective analysis of the surgical outcomes in terms of perioperative mortality, short-, mid-, and long-term postoperative complications and weight loss, with a median follow-up of 24 months.

The primary endpoint of the present study is the evaluation of the incidence of postoperative onset of severe GERD, esophagitis, and esophageal ulcers after LOAGB when conducted even as redo procedure for de novo reflux after LSG and as primitive treatment for morbid obesity.

The secondary endpoint is to evaluate the potential role of Braun anastomosis for the treatment of GERD, esophagitis, and anastomotic ulcers after LOAGB.

Surgical technique

Surgery is conducted laparoscopically under general anesthesia with the French technique (first operator position between the patient's legs, with moderate Trendelemburg).

Single intravenous administration of Cefazolin 2 g is always performed as ultrashort antibiotic prophylaxis.

After the induction of pneumoperitoneum with Veress needle, we place four accesses: 10 mm port on left subcostal space slightly lateral to emiclavear line (for 30 degrees angulated optic entry); 5 mm port on epigastric space; 5 mm port on low right hypochondrium for the operator's left hand and 15 mm port on left paraumbilical space e for the operator's right hand. In case of primary surgery, the right hypochondrium port should be 12 mm and the paraumbilical port 12 mm. A 38 Fr endogastric tube for calibration is inserted.

In cases of redo surgery after LSG, we start with the liberation of gastric remnant from peritoneal adhesions. Small omentum is opened, and the gastric tubule is sectioned at 12 cm from the esophagogastric junction with Medtronic Signia Tri-Staple™ (black cartridge [Medtronic, Minneapolis, MN]). In presence of gastric tubule dilatation, we remove the exceeding portion with Medtronic Signia Tri-Staple (black cartridge, one or two charges). If necessary, we control the staple line bleeding with bipolar coagulation or by over suturing. After the gastric tube is pushed and the staple line tractioned, we create a hole on the central part of the gastric tubule to insert the stapler tines, then we create another hole on the jejunal wall at about 180 cm from Treitz ligament, and we perform an antecolic termino-terminal anastomosis with Medtronic Signia Tri-Staple (purple cartridge). The gastric tube is placed through the anastomosis; the anastomotic hole is sutured with 18 centimeters Medtronic 3–0 V–Loc™. Intraoperative methylene blue test was performed to exclude a leak. A peritoneal drain is placed behind the anastomosis.

In cases of LOAGB as primary bariatric surgery procedure, gastric tubulization is completed by Medtronic Signia Tri-Staple (purple cartridge, two charges, and brown cartridge, one charge), inserting the staple through the 12 mm trocar on the left paraumbilical space.

In cases of LOAGBB, we perform a Braun anastomosis 25 cm from the gastrojejunal anastomosis with Medtronic Signia Tri-Staple (45 mm purple cartridge).

Postoperative care

All patients undergo an upper gastrointestinal X-Rays with oral contrast administration 2 days after the surgical procedure; in absence of anastomotic leakage, oral food intake is restarted and the abdominal drain is removed; patients are discharged the day after.

Upon discharge, all patients got a detailed dietary instruction sheet and were instructed to take supplemental minerals, multivitamins, as well as proton pump inhibitor for a least 3 months; the follow-up is planned at 1, 3, 6, 9, and 12 months after the operation, then at least once a year. Patients contact with surgeon and dietitian is guaranteed through phone numbers and e-mail contacts.

Gerd-Q questionnaire has been administered to all the patients 6 months after the surgical procedure; all subjects suffering of reflux symptoms underwent esophagogastroscopy.

Statistical analyses

The primary endpoint of the statistical analysis was to evaluate the differences between group A + B versus group C in terms of outcome proportions starting from aggregate data.

Comparisons between groups, in terms of categorical variables, have been performed using the Chi-square test or Fisher exact test for extreme proportions, as appropriate.

Statistical tests were based on a two-sided significance level of 0.05.

The SAS^® software, version 9.4, (SAS Institute, Inc., Cary, NC) was used to perform statistical analyses.

Results

Global analysis of postoperative results

All the 100 surgical procedures have been performed with laparoscopic approach; no cases of conversion to open procedure occurred. No patients were admitted to the intensive care unit. The mean operative time as recorded by the camera was 40 minutes (range 30–50 minutes). There were no deaths, and no procedure-related complications were reported. At 1-year of follow-up, mean body mass index (BMI) was 28.5 (range 29.5–26).

Group A: 50 patients (38 F-12 M) underwent one anastomosis LOAGB on previous LSG; indications have been severe de novo GERD (19 cases) and esophagitis (28 cases) not responsive to medical treatment; 3 patients affected by symptomatic GERD presented also weight regain (mean BMI 41, range 39–42). Mean age was 40 (range 35–60). No patients had complained about the presence of specific reflux symptoms before LSG, no patients had previously taken proton pump inhibitor drugs, and in no cases preoperative upper GI endoscopy had demonstrated esophagitis signs.

Mean BMI of the 38 patients who developed GERD and esophagitis without weight regain was 31 (range 28–33). Gerd-Q score was 12.

After LOAGB (mean follow-up: 24 months), mean BMI was 28.5 and Gerd-Q score was 5; at mean 36 months follow-up, mean BMI was 27.6, Gerd-Q score 5.

Among the 3 patients presenting weight regain, 2 patients also suffered of hypertension; at 1-year follow-up after surgery, pharmacological treatment has been stopped.

Mean percentage of total weight loss (%TWL) of the three patients presenting weight regain was 22.9; mean percentage of excess weight loss (%EWL) was 63.5.

Thirteen on 50 patients (26%) developed late postoperative complication: 2 cases (4%) of anastomotic ulcers (in one case with perforation and localized peritonitis); 4 cases (8%) of grade B and 2 (4%) of grade C esophagitis has been recorded; 5 patients (10%) complained about severe specific symptoms of GERD without endoscopic esophagitis signs, but with pathological findings at pH-metry test. All these cases have been treated by performing a Braun anastomosis 25 cm distal to the gastric bypass with complete healing of mucosal lesions and symptoms resolution.

Group B: 20 patients (12 F, 8 M) underwent LOAGB as primitive bariatric surgery procedure (median BMI 42, range 39–44). In 5 cases, GERD or grade A esophagitis had been previously detected. Mean age was 43 years (range 30–55). Seven patients presented hypertension as comorbidity, 4 patients type 2 diabetes.

Mean BMI at 12, 24, and 36 months follow-up were, respectively, 32, 28, and 27.5; at 24 months follow-up, mean % TWL was 24.6 and mean % EWL 69.4.

At a mean follow-up of 24 months, 5 of the 7 patients suffering of hypertension and all the 4 patients with diabetes stopped drug intake. Five patients (25%) developed severe GERD (2 without esophagitis, 3 with grade B esophagitis) not responsive to pharmacological therapy. Even in these 5 cases, a Braun anastomosis 25 cm distal to the gastric bypass with complete healing of mucosal lesions and symptoms resolution.

Group C: 30 patients (18 F, 12M) underwent Laparoscopic One Anastomosis Gastric Bypass with Braun anastomosis (LMGBB) as primary surgical treatment for morbid obesity. Mean BMI was 43 (range 38–45). Five patients (16.7%) presented signs and symptoms of GERD with grade B esophagitis (3 cases) and grade A esophagitis (2 cases). Hypertension was present in 8 patients, type 2 diabetes in 4. At a median 24 months follow-up, no cases of de novo reflux, anastomotic ulcers, or esophagitis have been recorded; median BMI at postoperative mean 12, 24, and 36 months follow-up were, respectively, 31, 29 (range 27–30), and 27.5; at 24 months follow-up, %TWL resulted 24.8 and %EWL 69.7; complete resolution of obesity-related comorbidities has been achieved in all cases.

Results are summarized in Tables 1 and 2.

Table 1.

Patient Demographic and Preoperative Clinical Data

	Group A	Group B	Group C
No. of patients	50	20	30
Male	12 (24%)	8 (40%)	12 (40%)
Female	38 (76%)	12 (60%)	18 (60%)
Mean age–range (years)	40 (35–60)	43 (30–55)	44 (22–55)
Mean preoperative BMI	33	42	43
Preoperative esophagitis	28 (56%)	3 (15%)	5 (16.7%)
Preoperative GERD symptoms	19 (38%)	2 (10%)	5 (16.7%)
GERD + weight regain	3 (6%)	—	—

BMI, body mass index; GERD, gastroesophageal reflux disease.

Table 2.

Postoperative Outcomes

	Group A (50 pts)	Group B (20 pts)	Group C (30 pts)
Mortality rate	—	—	—
Early morbidity rate (Clavien–Dindo >3)	—	—	—
Mean postoperative BMI (2 years follow up)	28.5	28	29
De novo esophagitis	6 (12%)	3 (15%)	—
De novo GERD Symptoms	2 (4%)	2 (10%)	—
Anastomotic ulcers	5 (10%)	—	—

BMI, body mass index; GERD, gastroesophageal reflux disease.

Statistical analysis showed a significant lower overall incidence of de novo esophagitis, GERD, and anastomotic ulcers in the groups of patients who underwent LMGBB, when compared to the two groups of LOAGB (P < .05).

Discussion

LOAGB is at least as effective as laparoscopic Roux-en-Y gastric bypass (LRYGB), if not more effective,^4,14 in terms of weight loss and comorbidity resolution; this technique takes less time to perform, requires a shorter learning curve, and is associated with fewer major complications.⁴

In their comparative analysis of LRYGB and LOAGB over a 10-year period, Lee et al.⁴ found that at 5 years of follow-up, patients undergoing LOAGB reached a significantly lower BMI (27.7 vs. 29.2) and higher EWL (72.9% vs. 60.1%); there was no significant difference in the improvement of comorbidities. A randomized study from the same group¹⁵ showed a lower complication rate for LOAGB (7.5% vs. 20%, P < .05) and a higher proportion of patients achieving an EWL >50% (95% vs. 75%, P < .05).

Literature seems to demonstrate that LOAGB has a high patient acceptance and most patients report a significant improvement in the quality of life^16–18 Although many patients report an increased bowel frequency, it does not negatively impact the quality of life. Lee et al.⁴ found similar quality-of-life scores between LRYGB and LOAGB patients in a comparative analysis of the two procedures. LOAGB patients had a better score in abdominal pain, but lower score in eating with pleasure and trouble with diarrhea than LRYGB patients.

De novo GERD after bariatric surgery is a very important clinical issue nowadays; the postoperative mid- and long-term onset of reflux can considerably worsen the patients quality of life and expose to cancer risk; the incidence of de novo GERD, as reported in literature, ranges from 8% to 44% after LSG,¹⁹ with a 17% incidence of Barrett esophagus²⁰; more encouraging results can be found after LOAGB (28.6%),²¹ and LRYGB (2%).²²

On the basis of in vitro and animal studies, it has been suggested that reconstruction with a loop configuration in patients undergoing gastric bypass will increase the risk of gastric and esophageal cancers because of increased biliary reflux.²³ On the contrary, duodenogastric biliary reflux is a physiological phenomenon, and the presence of bile in the stomach is a very common endoscopic finding in the normal population, and studies that can conclusively label bile as a carcinogen for gastric and/or esophageal cancer are lacking.

There is another potential angle to this debate. It would only be necessary to find a potential etiological agent, like bile reflux, if it was evident that patients who underwent Mason's loop gastric bypass and those who are at present undergoing LOAGB (both different procedures but with a similar loop reconstructions) have an increased risk of gastric and/or esophageal cancers. There has been gastric cancers reported in an LOAGB patient, but this was in the bypassed stomach and not the pouch.^24,25

GERD is strongly associated with obesity and a large number of patients seeking bariatric surgery suffer from it. LRYGB is regarded by some as the best antireflux operation²⁶ for obese patients suffering with GERD. LSG has a complex relationship with GERD²⁷ where a majority of the patients report an improvement, but some experience deterioration and others notice de novo reflux. Similarly, although GERD usually improves with LOAGB, several authors have reported troublesome reflux symptoms requiring revision to either LRYGB or LOAGBB.^5,8,10 It is also worth noting that reflux symptoms have also been noted after LRYGB²⁸ and may require surgical correction. In our 10 years experience of bariatric surgery, with over 6000 performed procedures, we reported an 8% incidence of de novo severe reflux after LSG, 4.5% after LMGB, and no cases of GERD or esophagitis after LMGBB. Lee et al.⁴ reported also revisions of LOAGB to LRYGB for intractable bile reflux.

Tolone et al.²⁹ studied GERD extensively in their study of patients without any preoperative GERD symptoms undergoing LOAGB and concluded that none of the 15 patients reported de novo GERD symptoms or esophagitis on endoscopic examination. Interestingly, two of these patients had a small hiatus hernia. The authors observed that LOAGB led to a significant reduction in both esophageal acid exposure and in reflux episodes, whereas LSG resulted in an increase in both.

Reported ulcer rates after LOAGB vary between 0.5% and 5.0%.^8,15,30 An ulceration rate of 4% seen in a systematic review¹⁴ was not dissimilar to what is typically observed after LRYGB. We have compared (data published as an abstract) marginal ulcer rates in patients undergoing LOAGB with that in those undergoing LRYGB³¹ and similarly to Lee's randomized study,¹⁵ we found no significant difference.

At the same time, experiences on LRYGB have found larger pouches to be associated with higher ulceration rates.³² If these findings were extrapolated to LOAGB, simply on the basis of a much larger pouch, a higher ulceration rate would be expected, but this result has never been proved; it remains to be examined if it is because of the possible buffering of excess acid with bile or due to potentially less tension on the anastomosis as a result of a longer pouch. Nonetheless, concerns that patients will have a very high ulceration rate because of constant exposure of anastomosis to bile are not confirmed by any author so far. Similar to LRYGB, ulcers in LOAGB also seem to be strongly associated with smoking,¹⁰ but unlike LRYGB, one expects persistent ulcers to be more easily amenable to treatment because of the ease of reversal or revision of the operation. Although ulcer perforations have been reported^10,14,28 after LOAGB, they seem to be restricted to smokers and can be treated by a simple closure similar to LRYGB ulcer perforations.

Conclusions

Despite many thousands of published cases, LOAGB continues to be controversial and many national societies do not regard it as a mainstream bariatric procedure. LOAGB has proven results when it comes to early safety and efficacy. It is noninferior to other established bariatric procedures and is particularly suited for metabolic and diabetic surgeries.³³

Braun anastomosis appears to be an effective surgical tool to avoid the onset of mid- and long-term complications related to gastroesophageal reflux; our current approach is to recommend LOAGBB as a primary procedure also for patients suffering with GERD and as redo after LSG with weight regain and with GERD and esophagitis.

Braun anastomosis could also be taken into consideration as redo procedure to treat severe GERD and esophagitis with a safe and effective profile; moreover, in case of gastrojejunal anastomosis leak, the presence of a Braun anastomosis gives the opportunity to easily place an endoprosthesis. In cases of weight regain, LOAGB with Braun can be revised by increasing the distance from Treitz ligament to gastrojejunal anastomosis and reconstructing the Braun anastomosis or converted into LRYGBP.

Further studies and comparative analysis with other procedures are needed to understand the safety of LOAGBB.

Informed Consent Statement

Informed consent was obtained from all individual participants included in the study.

Ethical Approval and Statement of Human and Animal Rights

The present study has been approved by the Ethics Committee of Our Institution.

All procedures performed in the study involving human participants were in accordance with the ethical standards of the Institutional and National Research Committee and with the Declaration of Helsinki 1964 and its later amendments or comparable ethical standards.

Footnotes

Disclosure Statement

No competing financial interests exist.

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