Does Reduction in Gastric Acid Secretion in Bariatric Surgery Increase Diet-Induced Thermogenesis?

Background: Patients who have undergone gastrectomy for benign ulcer do not develop obesity. Furthermore, morbidly obese patients who undergo biliopancreatic diversion (BPD), Roux-en-Y gastric bypass (RYGBP) and vertical banded gastroplasty (VBG) plus truncal vagotomy, may lose more weight compared with patients who undergo VBG alone. A common characteristic of the above is the reduction of gastric hydrochloric acid secretion. We investigated whether reduction in gastric acid increases dietary- induced thermogenesis because of maldigestion of foods, and this may account for the greater weight loss in the above situations. Materials and Methods: 22 volunteers without symptoms from the upper gastrointestinal tract were studied. Gastric pH was measured and resting energy expenditure (MREE), using indirect calorimetry, was determined before and 8 hours after consumption of a standard meal. Parameters were measured again after 2 months administration of proton pump inhibitors in all volunteers. Results: Although significant reduction of gastric acid secretion occurred (p<0.01), following administration of proton pump inhibitors, the fasting and postprandial MREE remained unchanged (p>0.05). Conclusions: The reduction in gastric acid secretion does not increase the energy requirements for digestion of foods and thus is neither the mechanism responsible for the increased weight loss observed after RYGBP or BPD, nor the explanation for the lean appearance of gastrectomized patients.     

Early Results of Laparoscopic Biliopancreatic Diversion with Duodenal Switch: A Case Series of 40 Consecutive Patients

Background: Biliopancreatic diversion with duodenal switch (BPD-DS) is an operation which provides one of the greatest maintained weight losses of any bariatric procedure.We looked at the safety and efficacy of laparoscopic BPD-DS for morbid obesity. Methods: A 150-200 ml sleeve gastrectomy was created and anastomosed to the distal 250 cm of divided ileum. The median length of the common channel was 100 cm. All patients were prospectively followed up to 12 months. Results: 40 consecutive patients underwent laparoscopic BPD-DS as a primary procedure for morbid obesity. Median patient body mass index (BMI) was 60 kg/m2 (range 42-85 kg/m2). Mean age was 43 ± 1 years (± SEM), with 12 males and 28 females. One patient was converted to open laparotomy (2.5%). Median operative time was 210 ± 9 minutes (range 110-360 minutes) with a significant correlation between BMI and operative time (p = 0.04). Median length of stay was 4 days (range 3- 210 days). There was one 30-day mortality (2.5%). Major morbidities occurred in 6 patients (15%), including 1 anastomotic leak (2.5%), 1 venous thrombosis (2.5%), 4 staple-line hemorrhages (10%) and 1 subphrenic abscess (2.5%). Median follow-up at 6 months (range 1-12 months) resulted in 46% ± 2% excess weight loss (EWL) and at 9 months 58% ± 3% EWL. Conclusion: Laparoscopic BPD-DS is a complex, yet feasible, procedure resulting in effective weight loss with an acceptable morbidity. A BMI >65 was associated with increased morbidity and mortality. A long-term study is needed to confirm efficacy and proper patient selection.     

Energy and Nitrogen Absorption after Biliopancreatic Diversion

Background: The strict long-term weight maintenance in good nutritional conditions observed after biliopancreatic diversion (BPD) needs to be explained. Materials and Methods: 15 operated subjects were maintained at an isoenergetic and isonitrogenic diet as similar as possible to their usual diet. Apparent absorption (AA) of energy, fat, nitrogen and calcium was calculated subtracting the fecal content, measured directly, from the oral intake, derived from tables.The alimentary protein absorption was directly determined by I¹²⁵ albumin oral administration. Results: Mean AA for energy and fat was 57% and 32%, respectively; AAs were unrelated as absolute value and negatively associated as percent of the intake with the energy and fat intake. I¹²⁵ intestinal absorption was 73%, while nitrogen percent AA was 57%, indicating higher than normal loss of endogenous nitrogen. Calcium AA was 551 mEq/day, 26% of the intake. A positive correlation between nitrogen and calcium AA as absolute values and alimentary intake was observed, while there was no correlation when AA were considered as per cent of the intake. Conclusions: For energy and fat, an increase in intake corresponds to an increase in percent malabsorption, so that the absolute amount absorbed tends to remain constant, accounting for the excellent weight maintenance observed following BPD. This was confirmed by a long-term hypernutrition study after BPD. On the contrary, for nitrogen and calcium, the percent absorption tends to remain constant when intake varies, so that an increase in alimentary intake results in an increased absolute amount absorbed.     

The Biliopancreatic Diversion with the Duodenal Switch: Results Beyond 10 Years

The BPD/DS, if properly performed, has the best long-term weight loss of any bariatric operation. It is easy to reverse or revise, has the least marginal ulcers, cures the highest percentage of co-morbidities, has the least failures, and permits normal although smaller meals. It is our opinion that the BPD/DS should be considered as the gold standard bariatric operation.     

Rhabdomyolysis after Biliopancreatic Diversion with Duodenal Switch

Rhabdomyolysis is an uncommon event in bariatric surgery. It can be caused by ischemia, crush injury, alcohol ingestion and drug intake, and as a consequence renal failure can develop. A few reports indicate that patients undergoing bariatric surgical intervention are at risk for rhabdomyolysis. A super-obese male (BMI 52 kg/m²) is reported, who underwent laparoscopic biliopancreatic diversion with duodenal switch (BPD/DS). Operative time was 265 minutes, and the BPD/DS operation was uneventful. Post-operatively, the patient complained of pain in both hips and the left shoulder, and suffered oliguria. He was treated with fluids (isotonic saline), bicarbonate, and mannitol. Despite this, he developed renal failure, which subsequently required hemodialysis. The patient died from arrhythmia and cardiac arrest on the 8th postoperative day. Obese patients undergoing bariatric surgery are at risk of rhabdomyolysis. Prolonged compression of the muscles during the surgical intervention, in long laparoscopic procedures, predisposes to this complication.     

Recommendations Regarding Obesity Surgery

In France, 1,000 obese persons per month undergo a bariatric operation. Obesity surgery requires coordination and monitoring of aftercare. The French public health-care insurer asked the medical associations involved in obesity management to provide guidelines for obesity surgery. The recommendations were developed by the national associations of Obesity, Nutrition and Diabetes: the Association Fran?aise d'Etudes et de Recherches sur l'Obésité (AFERO), member of the EASO and IASO; the Association de Langue Fran?aise pour l'Etude du Diabète et des Maladies Métaboliques (ALFEDIAM); the Société Fran?aise de Nutrition (SFN); and the Société Fran?aise de Chirurgie de l'Obésité (SOFCO). This article presents the short version of the guidelines.     

Twenty Years of Biliopancreatic Diversion: What is the Goal of the Surgery?

Background: Comparative evaluation of weight loss after bariatric surgery is difficult without definition of success and without a norm for presenting results. We explored the pertinence of defining success: a residual BMI <40 or <35 kg/m², and the need for reporting results with stratification by initial obesity and length of follow-up. Methods: Results of 1,271 consecutive biliopancreatic diversion (BPD) patients were compared when presented with or without stratification, and we searched for landmarks of success which would be shared by patients themselves. Results: Presented globally, after a mean follow-up of 7.9 ± 4.2 years, BMI decreased from 48.4 ± 9.4 to 31.3 ± 6.5, and only 10% and 26% of patients would have been considered failures with a residual BMI ≥ 40 or ≥ 35 respectively. Because heavier patients were losing less in terms of percentage ( P <0.0001) and regained weight faster ( P <0.0001), global and cumulative results failed to show a failure-rate doubling every 5 years and a very high failure-rate in heavier patients. The landmarks of BMI 40 and 35 were the same unconsciously used by patients to express their own perception of failure. For patients with an initial BMI <50, a residual BMI of 35 caused a significant drop in the degree of satisfaction from 90 to 40%. For super-obese, the same critical point was found at a BMI of 40 where satisfaction dropped from 91 to 57%. Conclusion: Landmarks of success at BMI 40 and 35 were realistic, reasonable and coincided with patients' own expectations. Since initial obesity and duration after surgery made so much difference in results, a comparison of different surgical approaches was useless without stratification for both factors together.     

Combining Laparoscopic Adjustable Gastric Banding and Biliopancreatic Diversion after Failed Bariatric Surgery

Background: A percentage of all types of bariatric surgery will fail. Our experience with failed biliopancreatic diversion (BPD) as a primary operation or revision operation for failed laparoscopic adjustable gastric banding (LAGB) convinced us that uncontrolled hunger is often the underlying cause. To control hunger after failed bariatric surgery,a novel approach combining LAGB with BPD-duodenal switch (DS) has been tried. Methods: Patients who had failed to lose weight after BPD or LAGB were considered in 2 groups. Group 1: patients who had failed LAGB underwent laparoscopic BPD-DS without sleeve gastrectomy, with the LAGB left in-situ. Group 2: patients who had failed primary (subgroup 2a) or revision (subgroup 2b) BPD had a LAGB placed with no other revision of their surgery. Results: 11 patients have undergone this form of revision surgery with little morbidity. Mean age at the original operation was 45 years, mean (range) BMI was 45.3 (38-62) kg/m². After the reoperation, at 3 months (9 patients) mean BMI was 30 kg/m² and at 6 months (4 patients) mean BMI was 27 kg/m². Conclusion: In this small study, combination surgery was safe and effective for failed BPD or LAGB. LAGB failure may be best managed with DS malabsorption without gastric resection.     

Outcome of Pregnancies after Biliopancreatic Diversion

Background: Severe obesity has deleterious effects on fertility and pregnancy outcomes. Although surgery is the best long-term treatment for severe obesity, there is a risk of gestational undernutrition in operated mothers because bariatric surgery reduces nutrient availability. This is a follow-up report of our initial findings regarding pregnancy and neonatal outcomes in biliopancreatic diversion (BPD) patients, with addition of a new cohort of children born to mothers after BPD. Methods: All women (n = 916) who had successfully undergone BPD in our hospital were mailed a questionnaire containing multiple-choice and essay questions concerning gynecologic and obstetric history, and pregnancy and neonatal outcomes in both preoperative and postoperative pregnancies. Patients operated between 1984 and 1995 (n = 568) were mailed an additional questionnaire regarding children's weight and height progress, and school performance. Perinatal records from our patients' obstetric clinics were also reviewed. Results: The questionnaire was completed by 783 women (85.5%). 251 postoperative pregnancies in 132 women resulted in 166 infants by 109 mothers. 47.0% of patients who were unable to become pregnant preoperatively were successful postoperatively. 90 out of 109 women (82.6%) reported an appropriate weight gain (9.1 ± 5.9 kg) during postoperative pregnancies. The incidence of fetal macrosomia decreased from 34.8 to 7.7%, with a concomitant increase in normalweight babies from 62.1 to 82.7%. The elevated miscarriage rate (26.0%) in these obese women persisted after surgery. Conclusion: Major weight loss following BPD improves the reproductive function of severely obese women. BPD provides major beneficial effects for both mother and child, including normalization of gestational weight changes, reduction of fetal macrosomia, and normalization of the infant's birth-weight. Our results speak in favor of delaying pregnancy in obese women until after the substantial surgical weight loss has occurred.     

The Decrease in Plasma Ghrelin Concentrations following Bariatric Surgery Depends on the Functional Integrity of the Fundus

Background: Gastric bypass surgery, which involves the production of a reduced stomach pouch,has been shown to markedly suppress circulating ghrelin concentrations. Since bypassing the ghrelin-producing cell population may be relevant to the disruption of fundic-derived factors participating in food intake signaling, the effect of weight loss induced by either adjustable gastric banding (AGB), Roux-en-Y gastric bypass (RYGBP) or biliopancreatic diversion (BPD) was studied. Methods: 16 matched obese patients [35.0 + 2.4 years; initial body weight 124.8 ± 5.7 kg; body mass index (BMI) 47.1 ± 2.2 kg/m²] in whom similar weight loss had been achieved by either AGB (n=7), RYGBP (n=6) or BPD (n=3) were studied. Blood was obtained for biochemical and hormonal analyses. Body composition was assessed by air-displacement-plethysmography. Results: Comparable weight loss (AGB: 26.1 ± 5.1 kg; RYGBP: 32.1 ± 5.0; BPD: 31.7 ± 6.1; P=NS) and decrease in percentage body fat (AGB: 10.0 ± 1.5%; RYGBP: 14.2 ± 2.8; BPD: 10.3 ± 1.0; P=NS) induced by bariatric surgery exerted significantly different (P=0.004) effects on plasma ghrelin concentrations, depending on the surgical procedure applied (AGB: 480 ± 78 pg/ml; RYGBP: 117 ± 34; BPD: 406 ± 86). Without significant differences in BMI, body fat, glucose, triglycerides, cholesterol, insulin and leptin levels, patients who had undergone the RYGBP exhibited statistically significant diminished circulating fasting plasma ghrelin concentrations compared with the other two bariatric techniques which conserve direct contact of the fundus with ingested food (P=0.003 vs AGB and P=0.020 vs BPD). Conclusion: Fasting circulating ghrelin concentrations in patients undergoing diverse bariatric operations depend on the degree of dysfunctionality of the fundus.