Study protocol of the DUCATI-study: a randomized controlled trial investigating the optimal common channel length in laparoscopic gastric bypass for morbid obese patients

Long-term weight loss of distal gastric bypass is moderately superior compared to proximal gastric bypass in patients with a BMI of 37-44 Kg/m2

PURPOSE

The laparoscopic Roux-en-Y gastric bypass (LRYGB) is one of the standard procedures in metabolic surgery. Different limb lengths have been proposed in the past to maximize weight loss (WL) and reduce metabolic complications. Distal gastric bypass surgery with a very short common channel (CC) (up to 100 cm) has been often criticized due to frequent side effects such as malnutrition, bone weakening and short-bowel syndrome. We introduced a modified version of a distal LRYGB with a 50-70 cm long biliopancreatic limb (BPL) and an intermediate short CC (120-150 cm). Our primary goal was to compare the long-term WL between distal and proximal LRYGB in two cohorts of patients. Secondary outcomes were weight regain (WR), insufficient weight loss (IWL), postoperative complications and metabolic changes 5 years after surgery.

METHODS

In this retrospective study we collected data from 160 patients operated between 2014 and 2015, with a BMI of 37-44 Kg/m2. 101 patients underwent a distal and 59 patients a proximal LRYGB in two bariatric centers. WL was calculated as percent of excess of BMI loss (%EBMIL), loss of body mass index (Delta-BMI), percent of excess weight loss (%EWL) and percent of total weight loss (%TWL). Data were collected 3, 6, 9, 12, 24, 48 and 60 months after surgery.

RESULTS

The distal LRYGB resulted in significantly better 5-year-WL compared to the proximal bypass in terms of %EBMIL (median at 5 years: 83% vs. 65%, p = 0.001), %TWL (median at 5 years: 32% vs. 26%, p = 0.017) and %EWL (median at 5 years: 65% vs. 51%, p = 0.029), with equal major complications and metabolic alterations. In addition, WR was significantly lower in patients with distal bypass (18% vs. 35%, p = 0.032).

CONCLUSIONS

Distal LYRGB with a 120-150 long CC results in better WL and WL-maintenance compared to proximal LRYGB without major side effects after five years.

Standard versus distal Roux-en-Y gastric bypass in patients with BMI 50-60 kg/m2: 5-year outcomes of a double-blind, randomized clinical trial

Background

The optimal surgical weight loss procedure for patients with a BMI of 50 kg/m² or more is uncertain. This study compared distal Roux-en-Y gastric bypass (RYGB) with standard RYGB.

Methods

In this double-blind RCT, patients aged 18–60 years with a BMI of 50–60 kg/m² were allocated randomly to receive standard (150 cm alimentary, 50 cm biliopancreatic limb) or distal (150 cm common channel, 50 cm biliopancreatic limb) RYGB. The primary outcome (change in BMI at 2 years) has been reported previously. Secondary outcomes 5 years after surgery, such as weight loss, health-related quality of life, and nutritional outcomes are reported.

Results

Between May 2011 and April 2013, 123 patients were randomized, 113 received an intervention, and 92 attended 5-year follow-up. Mean age was 40 (95 per cent c.i. 38 to 41) years and 73 patients (65 per cent) were women; 57 underwent standard RYGB and 56 distal RYGB. BMI was reduced by 15.1 (95 per cent c.i. 13.9 to 16.2) kg/m² after standard and 15.7 (14.5 to 16.9) kg/m² after distal RYGB; the between-group difference was −0.64 (−2.3 to 1.0) kg/m² (P = 0.447). Total cholesterol, low-density lipoprotein cholesterol, and haemoglobin A1c levels declined more after distal than after standard RYGB. High-density lipoprotein cholesterol levels increased more after standard RYGB. Vitamin A and vitamin D levels were lower after distal RYGB. Changes in bone mineral density, resting metabolic rate, and total energy intake were comparable.

Conclusion

Distal RYGB did not enable greater weight loss than standard RYGB. Differences in other outcomes favouring distal RYGB may not justify routine use of this procedure in patients with a BMI of 50–60 kg/m². Registration number: NCT00821197 (http://www.clinicaltrials.gov).

Presented in part as abstract to the IFSO (International Federation for the Surgery of Obesity and Metabolic disorders) conference, Madrid, Spain, August 2019.

Midterm Results from the Dutch Common Channel Trial (DUCATI): Superior Weight Loss Results of the Long Roux Limb Gastric Bypass in Comparison to the Standard Bypass at 3-Year Follow-Up

In the multi-center Dutch Common Channel Trial (DUCATI), a very long Roux limb Roux-en-Y gastric bypass (VLRL-RYGB: BP-limb 60 cm, Roux limb variable, and common channel 100 cm) was compared to a standard Roux-en-Y gastric bypass (S-LRYGB: BP-limb 60 cm, Roux limb 150 cm, and common channel variable) in the treatment of morbidly obese patients. As all trial patients are beyond 3-year follow-up a midterm analysis was performed to investigate the effect of the VLRL-RYGB.

METHODS

A total of 444 patients were randomized (1:1) to receive either a VLRL-RYGB or a S-LRYGB. Follow-up results for weight loss, effect on obesity-related comorbid conditions, complications, reoperation, and malnutrition are investigated.

RESULTS

At 3-year follow-up a significant difference in %TWL (34.0% vs. 31.4%, p = 0.017) and %EWL (84.7% vs. 76.6%, p = 0.043) was observed in favor of VLRL-LRYGB group. Overall complication rate 3-years after surgery was 15.8% in the VLRL-LRYGB group vs. 9% in the S-LRYGB group (p = 0.031). Eight (3.6%) patients in the VLRL-LRYGB group versus 2 (0.9%) in the S-LRYGB group (p = 0.055) required revisional surgery for malabsorption. In the VLRL-LRYGB group 71.9% of patients had resolution of T2DM versus 48.9% in the S-LRYGB group (p = 0.044).

CONCLUSION

At midterm FU a considerable, significantly increased effect on weight loss of the VLRL-LRYGB was observed compared to the S-LRYGB, with a higher risk of overall complications, but no significant nutritional side effects. These results might impact the current view on the value of the Roux limb in the discussion on optimum limb lengths in Roux-en-Y gastric bypass surgery.

Does the Length of the Common Channel as Part of the Total Alimentary Tract Matter? One Year Results from the Multicenter Dutch Common Channel Trial (DUCATI) Comparing Standard Versus Distal Roux-en-Y Gastric Bypass with Similar Biliopancreatic Bowel Limb Lengths

PURPOSE

Although the laparoscopic Roux-en-Y Gastric Bypass (LRYGB) is the gold-standard bariatric procedure, it remains uncertain what the optimal bowel limb lengths are to accomplish maximal weight loss while minimizing nutritional deficiencies and related gastro-intestinal complaints. The aim of this randomized controlled multicenter trial is to investigate the effect of significant lengthening of the length of the Roux limb (RL) at the cost of the length of the common channel (CC) while keeping the biliopancreatic limb (BPL) lengths the same on both study arms.

METHODS

Four hundred forty-four patients were randomized to receive either a Very Long Roux Limb LRYGB (VLRL-LRYGB) (variable RL length, BPL 60 cm, and CC 100 cm) or a Standard LRYGB (S-LRYGB) (RL 150 cm, BPL 60 cm, and a variable CC length). Results at 1-year follow-up for weight loss, effect on obesity-related comorbid conditions, complications, re-operation rate, malnutrition rate, and re-admission rate were investigated.

RESULTS

Weight loss at 1-year showed no significant differences for %EWL (84.3% versus 85.3%, p = 0.72) and %TWL (34.2% versus 33.6%, p = 0.359) comparing VLRL-LRYGB versus S-LRYGB. Malabsorption requiring surgical bowel length adjustment was observed in 1.4% in VLRL-LRYGB group versus 0.9% in S-LRYGB group (p = 0.316).

CONCLUSION

Significant lengthening of the RL at the cost of the common channel seems to have no effect on the weight loss at 1-year follow-up, which supports the theory that absorption of nutrients also occurs in the RL. Nevertheless, long-term results of the VLRL-LRYGB have to be awaited to draw final conclusions as part of the discussion towards optimal limb length in LRYGB surgery.

Gastrojejunal Anastomotic Technique. Does It Matter? Weight Loss and Weight Regain 5 Years After Laparoscopic Roux-en-Y Gastric Bypass

Purpose

The gastrojejunostomy during laparoscopic Roux-en-Y gastric bypass (LRYGB) can be constructed by hand sewn (HSA), linear (LSA) and circular (CSA) stapler technique. They are all considered safe; however, it is not known which the best technique is. Short-term follow-up suggest no difference in weight loss or weight regain between them. However, there is no information on these parameters in the long term. Theatre time and cost are other important factors defining the best way to form gastrojejunostomy.

Materials and Methods

In a prospective longitudinal cohort study consecutive patients following primary LRYGB were recruited to a bariatric database in a tertiary care centre. Anastomotic technique, diameter, the length of operations and associated costs, weight loss and weight regain were recorded. Patients were followed up for 5 years.

Results

A total of 385 patients with an initial body mass index of 47.1 kg/m² (35–68) were enrolled to this study. This decreased to 33.3 kg/m² (21–54 kg/m²) after 5 years. There was no difference in %TWL after 3 years, P = 0.296, or 5 years, P = 0.187, between the techniques. The number of patients with weight regain was not different after 3 years, P = 0.224, or 5 years, P = 0.795. All techniques had similar operative time. CSA has a higher material cost. Early anastomotic stricture was more common following HSA; however, the difference was not significant.

Conclusion

Mid-term weight loss and weight regain are not related to anastomotic technique, and there is no difference in operative time associated to them. Circular stapler technique has a higher material cost due to the additional stapler.

Effects of standard v. very long Roux limb Roux-en-Y gastric bypass on nutrient status: a 1-year follow-up report from the Dutch Common Channel Trial (DUCATI) Study

Laparoscopic Roux-en-Y gastric bypass (RYGB) is considered the ‘gold standard’ for surgical treatment of morbid obesity. It is hypothesised that reducing the length of the common limb positively affects the magnitude and preservation of weight loss but may also impose a risk of malnutrition. The aim of this study was to compare patients’ nutrient and vitamin deficiencies in standard RYGB with a very long Roux limb RYGB (VLRL-RYGB). This study was part of the multicentre randomised controlled trial (Dutch Common Channel Trial), including 444 patients undergoing an RYGB or a VLRL-RYGB. Laboratory results, use of multivitamin supplements and reoperations were collected at baseline and 1 year postoperative. Primary outcome measure was nutrient deficiency after 1 year postoperative. Secondary outcome measure was the reoperation rate due to malabsorption. In total, 227 patients underwent RYGB and 196 patients underwent VLRL-RYGB. Most common deficiencies at 1 year postoperative were ferritin (17·2–18·2 %), Fe (23·4–35·6 %), K (7·4–15·2 %), vitamin B12 (9·0–9·9 %) and vitamin D (22·7–34·5 %). Patients undergoing VLRL-RYGB had slightly but significantly lower levels of Ca, Fe and vitamin D compared with those undergoing RYGB at 1 year postoperative, but significantly higher levels of folic acid and Na. Reoperation rates due to malabsorption were not significantly different between RYGB (2/227, 0·9 %) and VLRL-RYGB (7/196, 3·6 %) (P = 0·088). We concluded that patients undergoing VLRL-RYGB had significantly lower levels of Ca, Fe and vitamin D compared with those undergoing RYGB at 1 year postoperative, but higher levels of folic acid and Na. Reoperation rates did not differ. Close monitoring on nutrient deficiencies should be performed in patients undergoing VLRL-RYGB.

Customization of biliopancreatic limb length to modulate and sustain antidiabetic effect of gastric bypass surgery

Although Roux-en-Y Gastric Bypass (RYGB) remains the most effective treatment for obesity and type 2 diabetes (T2D), many patients fail to achieve remission, or relapse. Increasing intestinal limb lengths of RYGB may improve outcomes, but the mechanistic basis for this remains unclear. We hypothesize biliopancreatic (BP) limb length modulates the antidiabetic effect of RYGB. Rats underwent RYGB with a 20-cm (RYGB-20cm) or 40-cm (RYGB-40cm) BP limb and were compared with control animals. After 2 and 4 wk, portal and systemic blood was sampled during intestinal glucose infusion. Portosystemic gradient was used to calculate intestinal glucose utilization (G_util), absorption (G_absorp), and hormone secretion. Intestinal morphology and gene expression were assessed. At 2 wk, G_absorp progressively decreased with increasing BP limb length; this pattern persisted at 4 wk. G_util increased ≈70% in both RYGB-20cm and -40cm groups at 2 wk. At 4 wk, G_util progressively increased with limb length. Furthermore, Roux limb weight, and expression of hexokinase and preproglucagon, exhibited a similar progressive increase. At 4 wk, glucagon-like peptide-1 and -2 levels were higher after RYGB-40cm, with associated increased secretion. We conclude that BP limb length modulates multiple antidiabetic mechanisms, analogous to the dose-response relationship of a drug. Early postoperatively, a longer BP limb reduces G_absorp. Later, G_util, Roux limb hypertrophy, hormone secretion, and hormone levels are increased with longer BP limb. Sustained high incretin levels may prevent weight regain and T2D relapse. These data provide the basis for customizing BP limb length according to patient characteristics and desired metabolic effect. NEW & NOTEWORTHY Biliopancreatic limb length in gastric bypass modulates multiple antidiabetic mechanisms, analogous to the dose-response relationship of a drug. With a longer biliopancreatic limb, Roux limb hypertrophy, increased glucose utilization, reduced glucose absorption, and sustained high incretin levels may prevent weight regain and diabetes relapse.

Tratamiento médico-quirúrgico de la obesidad en el SAHOS

La obesidad es uno de los factores de riesgo más importantes en los trastornos respiratorios relacionados con el sueño. Más de 70% de los pacientes con síndrome de apnea-hipopnea obstructiva del sueño (SAHOS) presenta algún grado de obesidad. La pérdida de peso, ya sea médica o quirúrgica, debe ser un objetivo primordial en el manejo del SAHOS al mejorar el índice de apnea-hipopnea (IAH) en un alto porcentaje, el cual se debe estimular en todos los pacientes. Siempre se debe iniciar con cambios en el estilo de vida a través de intervenciones con múltiples componentes que incluyen hábitos alimentarios, actividad física y soporte psicológico. Si después de 3 a 6 meses de tratamiento no se han alcanzado las metas de peso establecidas, se pueden formular medicamentos contra la obesidad o cirugía bariátrica. El riesgo actual de someterse a una cirugía bariátrica es bajo y los beneficios son evidentes.