Bariatric Surgery-How Much Malabsorption Do We Need?-A Review of Various Limb Lengths in Different Gastric Bypass Procedures

Prevention of malnutrition after one anastomosis gastric bypass: value of the common channel limb length

PURPOSE

Hypoalbuminemia and anemia are commonly observed indications for one anastomosis gastric bypass (OAGB) reversal and remain significant concerns following the procedure. Sufficient common channel limb length (CCLL) is crucial to minimize nutritional complications. However, limited literature exists regarding the impact of CCLL on OAGB outcomes. This study aimed to assess the effect of CCLL on weight loss and nutritional status in patients who underwent OAGB.

METHODS

A prospective cohort study was conducted from August 2021 to July 2022, involving 64 patients with a body mass index of 40-50 kg/m2. The standardized length of the biliopancreatic limb (BPLL) for all patients in this study was set at 175 cm. Additionally, the measurement of the common channel limb length (CCLL) was performed consistently by the same surgeon for all included patients.

RESULTS

The mean age and BMI of the patients were 39.91 ± 10.03 years and 43.13 ± 2.43 kg/m2, respectively, at the time of surgery. There was a statistically significant negative correlation between CCLL and percent total weight loss (%TWL) at the 12-month mark after OAGB (P = 0.02). Hypoalbuminemia was observed in one patient (1.6%), while anemia was present in 17 patients (26.6%) at the one-year follow-up. Statistical analysis revealed no significant difference in the incidence of anemia and hypoalbuminemia between patients with CCLL < 4 m and those with CCLL ≥ 4 m.

CONCLUSION

A CCLL of 4 m does not appear to completely prevent nutritional complications following OAGB. However, maintaining a CCLL of at least 4 m may be associated with a reduced risk of postoperative nutritional deficiencies.

Understanding and Managing Metabolic Deficiencies Post Bariatric and Esophagectomy Surgeries: A Narrative Review of the Literature

Gastrectomy and esophagectomy are the most performed surgeries in the treatment of both esophageal and gastric cancers. The type of esophagectomy depends on the type of malignancy, site of the tumor, criteria of resection, and field of resection. The three standard approaches to esophagectomy are the transhiatal approach, the left thoracoabdominal approach, and a three-stage procedure. The transhiatal approach involves abdominal and cervical incisions, while the left thoracoabdominal approach is a one-stage procedure that utilizes a single incision exposing the dissection field. The Ivor Lewis and McKeown esophagectomies are two-stage and three-stage surgeries that include laparotomy with right thoracotomy. Malabsorption often emerges as a significant postoperative complication following esophagectomy and gastrectomy surgeries. Malnutrition linked with these cancers has detrimental effects, including heightened rates of postoperative complications, elevated infection risks, delayed wound healing, reduced tolerance to treatment, diminished quality of life, and heightened mortality rates. Our narrative review summarizes and sheds light on solutions to treat malabsorption disorders and malnutrition after gastric bypass surgery. These solutions include methods such as adjustments, supplements, and treatment. Although more research is needed to confirm their effectiveness, these methods indicate potential for lowering the impact on patients' diets. By considering the beneficial implications of these effects and considering solutions, we aim to improve the management of these adverse effects, ultimately improving the overall health and postoperative outcomes of patients.

Technical Considerations in One Anastomosis Gastric Bypass-the Israeli Society of Metabolic and Bariatric Surgery Experience

BACKGROUND

One anastomosis gastric bypass (OAGB) is gaining popularity worldwide due to its safety and effectiveness. OAGB is the most commonly performed metabolic bariatric surgery (MBS) in Israel. Israel is the only country where OAGB is the most prevalent MBS. Our aim is to address OAGB technical aspects using a national survey completed by members of the Israeli Society of Metabolic and Bariatric Surgery (ISMBS).

MATERIALS AND METHODS

An online-survey composed of a 17-item-based questionnaire was sent to ISMBS members. All responses were collected and analyzed.

RESULTS

A total of 47/64 (73.4%) ISMBS members participated in the survey. Most surgeons (74.5%) had > 10 years of MBS experience, and most (61.7%) performed > 100 MBS/year. The majority (78.7%) perform OAGB as their most common procedure. Most surgeons fashion a 10-15-cm pouch and use a 36-Fr bougie, (57.4% and 38.3%). Regarding bowel length measurement, 70% use visual estimation and 10.6% routinely measure total small bowel length (TSBL). The most common reasons for creating a longer biliopancreatic limb (BPL) were high body mass index (BMI) and revisional surgery (83.3% and 66%, respectively). In a primary procedure of a patient with a BMI = 40, most (76.6%) would create a 150-200-cm BPL. In patients with a BMI > 50 or revisional cases, most (70.2% and 68.0%) would create a 175-225-cm BPL.

CONCLUSION

OAGB is the most prevalent MBS performed in Israel. This survey showed common preferences and variations among ISMBS members. Further studies are needed in order to standardize and build a consensus on OAGB technique.

Exocrine pancreatic insufficiency and pancreatic exocrine replacement therapy in clinical practice

Exocrine pancreatic insufficiency (EPI) is a complex condition that disrupts normal digestion and absorption. Patients with EPI may suffer from mild to debilitating malabsorption with a constellation of symptoms that can have a significant effect on quality of life and nutrition status. Pancreatic enzyme replacement therapy (PERT) is effective and safe to treat EPI and is the standard of care for this condition. A wide variety and various forms of these products exist, as well as numerous guidelines and recommendations. Obtaining PERT for patients can oftentimes be cost prohibitive. Determining the presence and extent of EPI can be challenging and patient specific, making it difficult for practitioners. This narrative review will explore these issues, as well as several disease states potentially affected by EPI, and review current management strategies.

Nonhepatic hyperammonemic encephalopathy following bariatric surgery: A systematic review

BACKGROUND

Nonhepatic Hyperammonemic encephalopathy (NHAE) following Bariatric Surgery (BS), mainly Roux-en-Y Gastric Bypass (RYGB) and Biliopancreatic Diversion (BPD) is a potentially devastating condition if not diagnosed and managed promptly.

METHODS

A literature review was performed using PRISMA guidelines. Eighteen studies and 3 conference abstracts with a total of 33 patients were included in this review.

RESULTS

Majority (28 patients, 84.8 %) had RYGB. Seven patients (21.2 %) had associated metabolic disorders. 60 % of patients presented with neurological symptoms or signs such as confusion, cognitive and/or psychomotor changes, and decreased reflexes. Two patients presented with status epilepticus. In 30 of the 33 patients an elevated serum ammonia levels was reported (90.9 %). The overall mortality was 39.3 %.

CONCLUSION

NHAE is a rare condition following bariatric surgery (in particular bypass procedures), carrying a high mortality rate. The signs and symptoms are predominantly neurological and may be mistaken for Wernicke's encephalopathy or other more common neurological conditions. Serum ammonia levels should be checked in those who present with these symptoms and signs. Prompt treatment might be life saving in patients with NHAE.

Optimal Small Bowel Limb Lengths of Roux-en-Y Gastric Bypass

PURPOSE OF REVIEW

Gastric bypass and biliopancreatic diversion (BPD) have come full circle, from a loop configuration to a Roux-en-Y and finally back to a loop configuration as one anastomosis gastric bypass and single-anastomosis duodenal switch. Most surgeons performing Roux-en-Y gastric bypass (RYGB) do not measure the common channel (CC) length and most surgeons performing BPD do not measure the biliopancreatic limb length (BPL).

RECENT FINDINGS

The small bowel length in humans is variable from as short as < 400 cm to as long as > 1000 cm. The combination of these two facts means that even if surgeons keep the limb lengths constant, surgeons will get variable limb length due to the variability of small bowel length in patients. Hence, outcomes of weight loss, resolution of medical problems, or developing nutritional deficiencies which are related to limb length are variable. In this article, we evaluate the published literature related to the effect of varying the Roux limb, BPL, CC, and total alimentary limb lengths on the outcomes of RYGB. We have focused on historical and current randomized controlled trials as well as systematic reviews and meta-analysis to outline the current literature and our interpretation of this literature.

One Anastomosis Gastric Bypass (OAGB) with a 150-cm Biliopancreatic Limb (BPL) Versus a 200-cm BPL, a Systematic Review and Meta-analysis

This is a systematic review and meta-analysis that assessed the impact of performing OAGB with a 150-cm BPL versus a 200-cm BPL concerning weight loss, comorbidities remission, and adverse nutritional effects. The analysis included studies that compared patients who underwent OAGB with a 150-cm BPL and 200-cm BPL. Eight studies were eligible for this review after searching in the EMBASE, PubMed central database, and Google scholar. The pooled analysis revealed favoring the 200-cm BPL limb length for weight loss, with a highly significant difference in the TWL% (p=0.009). Both groups showed comparable comorbidities remission. Significantly higher ferritin and folate deficiency rates were found in the 200-cm BPL group. Considering a 200-cm BPL when performing OAGB delivers a better weight loss outcome than a 150-cm BPL, which is at the expense of a more severe nutritional deficiency. No significant differences were found regarding the comorbidities' remission.

Effect of Intraoperative Lung Recruitment and Transversus Abdominis Plane Block in Laparoscopic Bariatric Surgery on Postoperative Lung Functions: A Randomized Controlled Study

Background

Morbid obesity may cause a restrictive condition. General anesthesia (GA) and supine posture both decrease lung capacity and functional residual capacity (FRC), altering the ventilation/perfusion ratio and raising the pulmonary shunt.

Objectives

To evaluate the impact of recruitment maneuver (RM) and transversus abdominis plane (TAP) block performed during laparoscopic bariatric surgery on spirometry, oxygenation, opioid requirements, and pain score assessed after surgery.

Methods

This pilot prospective randomized controlled study included 80 patients scheduled for elective laparoscopic bariatric surgeries (e.g., laparoscopic sleeve gastrectomy and laparoscopic gastric bypass) under GA. Patients were divided into four equal groups. All patients received a standardized postoperative analgesia regimen. Group I (control group), group II received TAP block after intubation and before surgical incision, group III received RM after intubation and after pneumoperitoneal insufflation, and group IV received RM after intubation and after pneumoperitoneal exsufflation and TAP block after intubation and before surgical incision.

Results

Forced vital capacity (FVC) and forced expiratory volume (FEV1) were significantly higher after group IV operation than in other groups. Intraoperative PaO2 and PaO2/FiO2 were significantly higher in groups III and IV compared to other groups. The numerical rating scale (NRS) at 1, 2, 4, 6, and 12h was significantly decreased in groups II and IV compared to other groups. Morphine consumption was significantly lower in groups II and IV compared to other groups.

Conclusions

TAP block combined with RM had better postoperative pulmonary function tests. Intraoperative oxygenation was higher in RM.

[Current evidence on loop length in intestinal bypass procedures]

BACKGROUND

Intestinal bypass procedures are well recognized for their long-term weight reduction and control of metabolic comorbidities. The selection of the length of the small bowel loop has a significant influence on the positive and also negative effects of the chosen procedure but national and international standardization are missing.

OBJECTIVE

The aim of this article is to give an overview of the current evidence on the various intestinal bypass procedures and the influence of the chosen small bowel loop length on the desired and adverse postoperative outcomes. The IFSO 2019 consensus recommendations on the standardization of bariatric surgery and metabolic procedures form the basis of these considerations.

MATERIAL AND METHODS

The current literature was searched for comparative studies addressing the question of different small bowel loop lengths in a Roux-en‑Y gastric bypass, one anastomosis gastric bypass, single anastomosis duodenoileal bypass with sleeve gastrectomy and biliopancreatic diversion (with duodenal switch).

RESULTS

Due to the heterogeneity of currently available studies and interindividual differences in total small bowel lengths in humans, it is difficult to give definitive recommendations for the choice of small bowel loop lengths. The longer the biliopancreatic loop (BPL) or the shorter the common channel (CC), the higher is the risk of (severe) malnutrition. To prevent malnutrition, the BPL should not be longer than 200 cm and the CC should have a length of at least 200 cm.

CONCLUSION

The intestinal bypass procedures recommended in the German S3 guidelines are safe and show good long-term outcomes. As part of the postbariatric follow-up, the nutritional status of patients following an intestinal bypass has to be followed-up on the long term in order to avoid malnutrition preferably prior to a clinical manifestation.

Feasibility of a new bariatric fully endoscopic duodenal-jejunal bypass: a pilot study in adult obese pigs

This study assessed a new natural orifice transluminal endoscopic surgery (NOTES) bariatric endoscopic procedure in obese adult pigs. This 14-week prospective study compared 6 adult male Yucatan test pigs with baseline mean age 1.5 years to 2 control pigs. The test pigs received a fully endoscopic NOTES-based duodenal-jejunal bypass including measurement of the bypassed limb and creation of a gastrojejunal anastomosis (GJA) using a gastrojejunal lumen-apposing metal stent (GJ-LAMS) at Week 0, placement of a duodenal exclusion device (DED) at Week 2, and endoscopic examinations at Weeks 6 and 10. At Week 14, the pigs were sacrificed for necropsy. All endoscopic procedures were technically successful. By Week 14, the controls had gained a mean 1.1 ± 2.1 kg (+ 1.6%) while the intervention animals lost a mean 6.8 ± 3.9 kg (- 10.5%) since baseline. GJ-LAMS migrations occurred in 3 pigs, two of which also had DED migration and/or partial dislocation. Two other pigs died, one with aberrant splenic vein positioning near the GJA and the other from an unknown cause. An endoscopic bariatric bypass procedure with controlled bypass length was technically successful in all the cases and led to weight loss in test animals. Safety concerns must be further addressed.

Single Anastomosis Jejuno-ileal (SAJI): a New Model of Malabsorptive Revisional Procedure for Insufficient Weight Loss or Weight Regain After Roux-en-Y Gastric Bypass

BACKGROUND

In case of insufficient weight loss or weight regain or relapse of weight-related comorbidities after Roux-en-Y gastric bypass (RYGB), other procedures such as reduction of a large gastric pouch and stoma, lengthening of the Roux limb, conversion to sleeve gastrectomy and/or bilio-pancreatic diversion with duodenal switch have been advocated. Single anastomosis jejuno-ileal (SAJI) is a new revisional simple operation performed after RYGB failure which adds malabsorption to the previous gastric bypass.

METHODS

SAJI includes a single jejuno-ileal anastomosis specifically joining the ileum 250-300 cm proximal to the ileo-caecal valve and the jejunum 30 cm below the gastro-jejunal anastomosis on the Roux limb of the previous RYGB. Thirty-one patients underwent SAJI for insufficient weight loss and/or weight regain after RYGB. The percent total weight loss (%TWL) after RYGB and before SAJI was 21.8 ± 7.8. All SAJI operations were performed laparoscopically. The SAJI mean operating time was 145 min.

RESULTS

Regarding weight loss after SAJI, %TWL is 27.2 ± 7.4, 31.2 ± 6.4, 33.7 ± 5.9 and 32.9 ± 5.2 at 12, 24, 36 and 48 months, respectively. Our series recorded a low rate of peri-operative and medium-term complications with a low grade of severity (Clavien-Dindo classification grade). One patient required reoperation 36 days after SAJI for epigastrium incarcerated incisional hernia at the previous RYGB laparotomy site. Mortality was 0. Comorbidity reduction/resolution after SAJI is 83.2% for type 2 diabetes mellitus, 42.8% for arterial hypertension, 72.8% for dyslipidemia and 45.3% for OSA.

CONCLUSIONS

Treatment of failed RYGB is challenging. SAJI is a less complicated, purely low invasive malabsorptive operation that should reach satisfactory %TWL and comorbidity reduction/resolution.

Outcomes and Effects of 250-cm Biliopancreatic Limb One Anastomosis Gastric Bypass in Patients with BMI > 50 kg/m2 with Total Bowel Length > 6 m: a 2-Year Follow-up

Background

There is a controversy on the suitable bariatric procedure for patients with BMI > 50 kg/m². Many surgeons prefer the Roux en-Y gastric bypass (RYGB) while others resort to long biliopancreatic limb (BPL) one anastomosis gastric bypass (OAGB).

Methods

This study included patients with BMI > 50 kg/m² who underwent 250-cm BPL OAGB with total bowel length (TBL) > 6 m and completed 24-month follow-up from July 2015 to November 2021. Demographic data with preoperative weight, BMI, hypertension (HTN), DM (HbA1C), Hb, iron, calcium, albumin, vitamin D, and parathormone levels (PTH) were recorded. Operative time, total bowel length (TBL), residual length (RBL), complications and postoperative weight, BMI, % of total weight loss (%TWL), HTN, DM, and alkaline reflux as well as Hb, iron, calcium, albumin, vitamin D, and PTH levels were recorded at 6, 12, 18, and 24 months.

Results

OAGB had a significant decrease in weight, BMI (25.6 ± 3.4 kg/m² at 24 months) with %TWL of 48 ± 5% at 24 months. TBL and RBL were 6.7 ± 0.65 and 4.2 ± 0.65 m respectively. %BL (RBL/TBL*100) was 62.4 ± 3.3%. The HbA1C, HTN, and alkaline reflux incidence were 5.5 ± 0.29 gm%, 1.4%, and 3.7% respectively at 24 months. Hb, iron, calcium, albumin, and vitamin D showed a significant decrease but still within normal range, and PTH showed a significant increase at 24 months.

Conclusion

Long BP (250 cm) OAGB in patients with BMI > 50 kg/m² with TWL > 6 m had good results in the achievement of weight loss and weight maintenance goals with remission of associated comorbidities as HTN and DM.

Graphical abstract

Standard Biliopancreatic Limb (50 cm) Roux-en-Y Gastric Bypass Versus Long Biliopancreatic Limb (100 cm) Roux-en-Y Gastric Bypass in Patients with Body Mass Index 40-50 kg/m2: a Randomized Prospective Study

BACKGROUND

Roux-en-Y gastric bypass (RYGB) is a widely performed procedure worldwide especially with the presence of associated medical conditions. Patients with body mass index (BMI) 40-50 kg/m² are at more risk of weight regain and relapse of comorbidities. There is a controversy on the optimum alimentary (AL) and biliopancreatic (BPL) limb lengths to be used in RYGB to achieve weight loss and remission of comorbidities without causing nutritional deficiencies in those patients.

STUDY DESIGN

hundred-and-fifty patients with BMI between 40 and 50 kg/m² were divided equally into 2 groups undergoing standard RYGB (S-RYGB) with AL:150 cm and BPL: 50 cm and long biliopancreatic RYGB (L-RYGB) with AL: 100 cm and BPL: 100 cm. BMI, % of total weight loss (%TWL), effect on diabetes (DM), hypertension (HTN), dyslipidemia, and nutritional statuses were recorded at 1, 2, and 3 years.

RESULTS

Only 64/75 patients in S-RYGB and 57/75 patients in L-RYGB completed the study. L-RYGB had faster weight loss, higher %TWL, and less BMI than S-RYGB with the maintenance of achieved weight. L-RYGB had better control of DM and dyslipidemia than S-RYGB. There were no significant differences in nutritional status between S-RYGB and L-RYGB rather than lower levels of calcium and Hb and higher levels of PTH in L-RYGB yet they remain within the normal range.

CONCLUSION

The application of L-RYGB helps in achieving faster weight loss for a longer period with better remission of associated comorbidities as DM, HTN, and dyslipidemia in patients with BMI 40-50 kg/m² but with effects on the nutritional status.

Outcome of Sleeve Gastrectomy Converted to Roux-en-Y Gastric Bypass and One-Anastomosis Gastric Bypass

Purpose

Sleeve gastrectomy (SG) is the commonest bariatric procedure worldwide but there is also a high conversion rate mainly due to weight regain and gastroesophageal reflux disease (GERD) reported in studies with long-term follow-up. The aim of this study is to highlight benefits and limitations of converting SG patients to Roux-en-Y gastric bypass (RYGB) and one-anastomosis gastric bypass (OAGB).

Setting

Retrospective cross-sectional-study, medical university clinic setting.

Methods

This study includes all patients converted from primary SG to RYGB or OAGB by 12/2018 at the Medical University of Vienna. Patients were examined using gastroscopy, esophageal manometry, 24-h pH-metry, and questionnaires.

Results

Fifty-eight patients were converted from SG to RYGB (n = 45) or OAGB (n = 13). Total weight loss of patients converted to RYGB and OAGB was 41.5% and 44.8%, respectively, at nadir. Six patients had Barrett’s esophagus (BE) after SG. In four out of these six patients, a complete remission of BE after conversion to RYGB was observed; nevertheless, two patients after RYGB and one after OABG newly developed BE. Clinical GERD improved at a higher rate after RYGB than after OAGB. Both revisional procedures improved associated medical problems.

Conclusion

Conversion to RYGB is probably the best option for patients with GERD after SG. OAGB has shown a low potential to cure patients from GERD symptoms after SG. In terms of additional weight loss and remission of associated medical problems, both procedures studied were equal. Surveillance gastroscopies every 5 years after SG revisions are recommended.

Graphical abstract