Clinical Research Directory

Dexmedetomidine Versus Ketamine as Adjuvants in Bariatric Surgery

This randomized controlled trial aims to compare the analgesic efficacy of dexmedetomidine infusion versus low-dose ketamine infusion as adjuvants in bariatric surgery. The study includes 90 patients undergoing bariatric surgery at Menoufia University Hospital, randomized into three groups: dexmedetomidine, ketamine, and control (placebo). Primary outcomes include total morphine consumption intra- and post-operatively. Secondary outcomes include postoperative pain scores, total analgesic consumption, time to first analgesic request, hemodynamic parameters, and patient satisfaction. This study seeks to explore safer, more effective pain management strategies to minimize opioid use in bariatric surgery patients.

Impact of a Pro-diversity Gut Microbiota Diet After a Bariatric Surgery on Gut Microbiota, Eating Behaviour and Sensory Function

Bariatric surgery is the most effective treatment for long-term weight loss and reducing obesity-related health risks. It alters the gastrointestinal tract as well as metabolic and hormonal functions, influencing eating behaviour. However, weight loss outcomes and long-term maintenance vary between patients, likely due to changes in the gut microbiota. Dietary recommendations aimed at improving microbiota diversity could help support sustained weight loss after surgery. The BariaGut Taste study aims to compare two dietary approaches following bariatric surgery: nutritional counselling promoting gut microbiota diversity versus standard nutritional counselling. One year after surgery, the study will evaluate differences in microbiota diversity, changes in food preferences and eating behaviours, sensory profiles (taste, smell), levels of digestive and gut hormones fasting, before and after eating, cardiometabolic parameters, mental health, physical activity, and more, to better understand Bariatric surgery is the most effective treatment for long-term weight loss and reducing obesity-related health risks. It alters the gastrointestinal tract as well as metabolic and hormonal functions, influencing eating behaviour. However, weight loss outcomes and long-term maintenance vary between patients, likely due to changes in the gut microbiota. Dietary recommendations aimed at improving microbiota diversity could help support sustained weight loss after surgery. The BariaGut Taste study aims to compare two dietary approaches following bariatric surgery: nutritional counselling promoting gut microbiota diversity versus standard nutritional counselling. One year after surgery, the study will evaluate differences in microbiota diversity, changes in food preferences and eating behaviours, sensory profiles (taste, smell), levels of digestive and gut hormones fasting, before and after eating, cardiometabolic parameters, mental health, physical activity, and more, to better understand the mechanisms that may explain variations in response to bariatric surgery. The BariaGut Taste study is a prospective, randomized, controlled trial with two parallel groups, involving non-diabetic patients aged 25 to 65 y undergoing either sleeve gastrectomy or Roux-en-Y gastric bypass. The trial will be conducted at the digestive surgery department of Edouard Herriot Hospital, the endocrinology-diabetes-nutrition department of Lyon Sud Hospital Center, and the Human Nutrition Research Center Rhône-Alpes. 60 participants are expected to be recruited, with 30 in each arm. Participants will be enrolled before surgery during a routine care visit with the surgeon. They will then undergo a metabolic assessment visit conducted exclusively for research purposes. This visit will allow to collect baseline data on primary outcomes via blood, expired air, and stool samples, anthropometric measurements, indirect calorimetry, a battery of questionnaires (TFEQ-21, DEBQ, PHQ-9, SF36, GSES, PANAS, ESUL, BES, DERS, GAD-7, IPAQ, BAQ, GSRS, sensory alterations, Bristol and Likert scales, and FNS), computerized food preference tests (LFPQ), and a standardized, video-recorded ad libitum buffet. Participants will be followed up at 3, 6, and 12 months after surgery through visits combining clinical care and research assessments. The dietary interventions specific to each group will be provided since the 3-month visit. The assessments conducted before surgery will be repeated at 6 and 12 months, also integrating clinical care objectives. Additional blood, stool, and adipose tissue samples collected during surgery will be stored to create a biobank.

Indocyanine Green Fluorescence Angiography (ICG-FA) in Revisional Bariatric Surgery

This study will compare different doses of a green fluorescent product that is administered during weight loss surgery in order to observe where blood vessels are located. There is uncertainty around the optimal dose of this product for patients with obesity, so this study will aim to study if the dose in the minimal range recommended by international guidelines is sufficient for most patients or if higher doses are needed with increasing body mass index.

Digital Follow-Up and Nursing Education in Bariatric Surgery Patients

This randomized controlled experimental study aims to evaluate the effect of a PHP-MySQL database-based digital follow-up system combined with structured nursing education on quality of life, body mass index (BMI), and exercise habits in patients undergoing bariatric surgery. Although bariatric surgery is an effective treatment for morbid obesity, long-term success depends largely on adherence to lifestyle modifications, including regular physical activity and sustained behavioral change. Participants will be randomly assigned to either an intervention group or a control group. The intervention group will receive structured nursing education along with an 8-week digitally monitored exercise program starting at postoperative month four. The control group will receive standard postoperative care. Outcomes will be assessed using the Moorehead-Ardelt Quality of Life Questionnaire II (MA-II), BMI measurements, and the International Physical Activity Questionnaire (IPAQ). The study aims to provide evidence for integrating digital health technologies and structured nursing interventions into postoperative bariatric care.

Disordered Eating and Recurrent Weight Gain After MBS

Obesity represents an increasingly serious public health problem worldwide. According to the World Health Organization, one in eight individuals globally is affected by obesity. Bariatric surgery (BS) is recognized as the most effective treatment for severe obesity and has been shown to significantly improve obesity-related comorbidities. However, despite initially successful surgical outcomes, a substantial proportion of patients experience insufficient weight loss (IWL) or weight regain (WR) after surgery. Previous studies have identified multiple factors associated with post-bariatric IWL and WR, including older age, low socioeconomic status, higher baseline body mass index (particularly preoperative BMI \>50 kg/m²), type of surgical procedure, hormonal mechanisms, poor adherence to postoperative dietary recommendations, maladaptive eating behaviors, insufficient physical activity, and the presence of psychiatric comorbidities. Among these, behavioral factors appear to play a particularly critical role. Irregular eating patterns such as loss of control eating, maladaptive behaviors such as grazing, non-adherence to dietary guidelines, and a return to preoperative eating habits are frequently associated with weight regain. Additionally, physiological mechanisms, including increased appetite, food cravings, and altered hormonal regulation of energy intake, may further contribute to this process. Grazing behavior-defined as repetitive consumption of small amounts of food accompanied by a sense of loss of control-has been consistently associated with poorer weight outcomes after bariatric surgery. A large meta-analysis reported grazing prevalence rates between 16.6% and 46.6%, with weight regain observed in nearly half of post-bariatric patients. Moreover, lack of structured nutritional follow-up has been shown to significantly increase the risk of weight regain. Neurobehavioral changes also occur after surgery: while appetite and responsiveness to palatable foods typically decrease during the first postoperative year, these effects often diminish over time, with hunger, cravings, and portion sizes gradually increasing in some individuals. Long-term weight regain has been closely linked to disordered eating behaviors, including emotional eating, binge eating, compulsive eating, food addiction, and loss of control eating. Recent studies have demonstrated significant associations between weight regain and binge eating disorder, eating disinhibition, and impulsivity. Qualitative research further highlights that many patients struggle to manage emotional eating and require ongoing psychological and dietary support following surgery. Despite growing evidence emphasizing the behavioral and psychological components of post-bariatric outcomes, comprehensive studies that simultaneously evaluate nutritional status, eating disorders, and emotional factors in individuals experiencing IWL or WR remain limited. Therefore, the present study aims to assess nutritional status, eating disorder symptoms, and emotional factors in individuals who experience insufficient weight loss or weight regain after bariatric surgery. By integrating anthropometric, nutritional, behavioral, and emotional assessments within the same sample, this study seeks to provide a multidimensional perspective and contribute to the development of more effective multidisciplinary follow-up and psychodietetic interventions.

Flow-Controlled Versus Volume-Controlled Ventilation in Bariatric Surgery

This prospective trial aims to compare the effects of flow-controlled ventilation (FCV) and volume-controlled ventilation (VCV) on intraoperative airway pressures and oxygenation in bariatric surgery under general anesthesia. Obesity is associated with altered respiratory mechanics, reduced functional residual capacity, and increased airway pressures, making the selection of an optimal ventilation strategy particularly important in this patient population. Adult patients aged 18-65 years with a body mass index ≥30 kg/m² and American Society of Anesthesiologists (ASA) physical status II-III will be allocated to receive either FCV or VCV as part of routine intraoperative mechanical ventilation. Ventilatory parameters, including peak and plateau airway pressures, pulmonary compliance, will be recorded at predefined intraoperative time points. The primary endpoint of the study is the PaO₂ value measured at the 20th minute under an FiO₂ of 0.8-1.0. By providing comparative data on respiratory mechanics and oxygenation, this study aims to contribute to the identification of lung-protective ventilation strategies and to optimize intraoperative ventilatory management in bariatric surgery.

Effects of Respiratory Muscle Training in Post-bariatric Surgery Patients

Obesity is a health condition caused by excessive accumulation of body fat. This condition is linked to the development of chronic diseases and also places increased stress on the respiratory system, leading to respiratory disorders, exacerbation of preexisting respiratory conditions, and a decline in physical capacity and exercise tolerance. Respiratory muscle training has been shown to have beneficial effects on respiratory function in these patients, although the effects this strategy has on other metabolic and physiological aspects related to exercise and obesity that are affected remain unclear.

Scalp Hair Metabolomics in Severe Obesity

The purpose of this research study is to investigate how body weight and weight-loss surgery affect the natural chemicals found in scalp hair over time. We will also find out how common and severe hair thinning/hair loss and muscle loss are in the first 6 months after bariatric surgery.

BAR-TAX - Tranexamic Acid in Bariatric Surgery.

Perioperative bleeding is a relevant complication in bariatric surgery and may lead to hemoglobin decrease, blood transfusions, reinterventions, prolonged hospital stay, and increased healthcare costs. Tranexamic acid (TXA), an antifibrinolytic agent, has demonstrated efficacy in reducing surgical bleeding in several surgical specialties, with a favorable safety profile when appropriately used. However, evidence in bariatric surgery remains limited, particularly considering the intrinsically increased thromboembolic risk of obese patients. The BAR-TAX study is a prospective, single-center study conducted in a high-volume bariatric surgery center, aiming to evaluate the efficacy and safety of perioperative TXA administration compared with standard care without TXA. The primary objective is to assess whether TXA reduces the incidence of clinically significant bleeding within 48-72 hours after bariatric surgery. Secondary objectives include evaluation of hemoglobin drop, transfusion rates, need for hemostatic procedures or reoperation, thromboembolic events, postoperative complications, length of hospital stay, readmissions, and TXA-related adverse events.

Predicting Weight Loss After Bariatric Surgery in Patients With Obesity

As with other nutritional strategies, the clinical response to bariatric surgery can be highly variable, with weight regain being a frequent occurrence. Among multiples factors, co-occurrence of eating disorders such as binge eating disorder has been implicated in insufficient clinical response. Improving our ability to predict how patients will respond to surgery is necessary in order to tailor the care pathways we offer. The mechanisms involved in disturbances of eating behaviour before and after surgery remain largely unknown. This study aims to identify the predictive factors of weight loss after bariatric surgery, as well as the cognitive and biological mechanisms that mediate this effect.

Glucagon Dose-Response in Patients With Post-Bariatric Hypoglycemia

The purpose of the study is to determine how blood sugar levels in individuals with and without hypoglycemia after bariatric surgery respond to different doses of glucagon, a hormone that is usually present in your body that regulates blood sugar levels. In this study, there will be 4 visits to the clinical research center. In the first visit, medical history and physical exam will be performed, and blood samples will be taken to assess overall health. During visit 2, a continuous glucose monitor will be placed under the skin. (This may be combined with visit 1, depending on the schedule of visits.) In visit 3, we will test the effect of a total of 4 different doses of glucagon, in increasing doses. In visit 4, we will test the effect of a total of 3 doses of glucagon, in decreasing doses. For both visit 3 and 4, we will infuse labeled stable glucose to allow us to measure how much glucose the body is making, and will measure levels of hormones which regulate glucose, such as insulin and glucagon.

One-Year Outcomes After Conversion Bariatric Surgery

Obesity is a growing global public health problem, and bariatric surgery is currently the most effective treatment for achieving sustained weight loss and improving obesity-related comorbidities. However, a subset of patients experience inadequate weight loss or weight regain following primary bariatric surgery, which may lead to the recurrence of metabolic complications and reduced quality of life. In such cases, conversion bariatric surgery, defined as the surgical conversion from one bariatric procedure to another, is considered an important therapeutic option. Despite the increasing number of conversion procedures, comprehensive longitudinal data evaluating anthropometric, biochemical, and nutritional outcomes after conversion bariatric surgery remain limited. This study aims to prospectively evaluate individuals undergoing conversion bariatric surgery due to weight regain following primary bariatric surgery. Anthropometric measurements, biochemical parameters, and nutritional status will be assessed preoperatively and at 1 year after surgery. By evaluating weight loss outcomes together with metabolic and nutritional changes, this study seeks to provide clinically relevant evidence to guide postoperative follow-up strategies, optimize nutritional management, and support multidisciplinary care in patients undergoing conversion bariatric surgery.

Effect of Intraoperative Salbutamol Administration on Mechanical Power and Respiratory Mechanics in Obese Patients Undergoing Laparoscopic Bariatric Surgery

The primary objective of this study is to evaluate the effect of intraoperative salbutamol administration on mechanical power in obese patients undergoing laparoscopic bariatric surgery under general anesthesia. Mechanical power will be measured at predefined intraoperative time points (T0, T1, and T2), and changes over time will be compared to determine the impact of salbutamol on the overall energy delivered to the respiratory system during mechanical ventilation. Secondary objectives include the assessment of intraoperative respiratory mechanics, including peak airway pressure (Ppeak), plateau pressure (Pplat), driving pressure (Pdrive), airway resistance (Raw), and lung compliance, as well as gas exchange parameters (SpO₂, EtCO₂) and hemodynamic variables (mean arterial pressure). Postoperative pulmonary outcomes will be evaluated using the Melbourne Group Scale (MGS), with a score greater than 4 indicating the presence of postoperative pulmonary complications. The study aims to investigate whether improvement in intraoperative mechanical power and respiratory mechanics is associated with a reduction in postoperative pulmonary complications in this high-risk population.

Gastro-Intestinal Digestion and Physiology After Bariatric Surgery

The goal of this clinical trial is to characterize gastrointestinal digestion and physiology in patients after bariatric surgery, or people living with obesity. The main question it aims to answer is: what is the status of gastrointestinal digestion and physiology after bariatric surgery? Participants will have two study visits: 1) participants will undergo collection of gastrointestinal samples and 2) participants will ingest an ingestible capsule that measures multiple physiological parameters along the gastrointestinal tract.

Magnetic Compression Anastomosis Procedure for Partial Jejuno-ileal Diversion: Evaluating the Feasibility of a Novel Endoscopic Magnetic Metabolic Interventional Therapy

English, Hindi and Gujarati

Physiologic Response to Bariatric Surgery and the Impact of Adjunct Semaglutide in Adolescents

The study plans to learn more about what happens to the body after bariatric surgery in people 12 to 24 years old. The study aims to understand why people respond differently to bariatric surgery and how to define success beyond weight loss alone. The study also plans to learn more about whether a medication (semaglutide) can help people 12 to 24 years old who, between 1 and 2 years after bariatric surgery, have not lost as much weight as expected.

EFFECTS OF SUPERVISED PHYSICAL EXERCISE AFTER BARIATRIC SURGERY ON MUSCLE MASS AND BONE DENSITY (OBEFIT STUDY)

CLINICAL TRIAL ON THE EFFECT OF SUPERVISED PHYSICAL EXERCISE AFTER BARIATRIC SURGERY ON MUSCLE MASS AND BONE DENSITY (OBEFIT STUDY)

Intravenous Lidocaine Infusion Versus Intravenous Dexmedetomidine Infusion During Sleeve Gastrectomy

Although laparoscopic (LAP) bariatric surgery is minimally invasive. Following any laparoscopic procedure, patients typically experience the peak of postoperative pain within the first 24 hours. This intense pain gradually subsides, with significant relief usually occurring by the 2nd or 3rd postoperative day. The initial peak and subsequent decline in pain intensity highlight the importance of effective early pain management strategies to ensure patient comfort and recovery during this critical period. Inadequate management of postoperative pain can result in serious complications. Lidocaine is increasingly recognised as a vital adjunct in managing perioperative pain. Its efficacy extends beyond traditional local anaesthetic applications, as it also demonstrates analgesic, anti-hyperalgesic, and anti-inflammatory properties. Dexmedetomidine is a highly selective alpha-2 adrenergic agonist with hypnotic, sedative, anxiolytic, sympatholytic, and analgesic effects, while causing minimal respiratory depression

Patient Reported Outcome After Bariatric Surgery

Prospective association study to analyse patients' outcome after bariatric surgery. Outcome comprises postoperative pain, analgesia, postoperative side-effects, long-lasting pain, patients' impairment in daily living.

Preventing Muscle Loss After Bariatric Surgery: Protein-Collagen Supplementation and Resistance Exercise

The aim of this clinical trial is to investigate the effectiveness of collagen, considered a new approach to prevent muscle mass loss after bariatric surgery, and to demonstrate the relationship between this effect and exercise. The key questions it aims to answer are: Does whey protein supplementation with collagen combined with resistance exercise prevent muscle mass loss after bariatric surgery? Do whey protein supplementation with collagen combined with resistance exercise affect fat mass after bariatric surgery? Researchers will compare collagen with whey protein. The study groups and interventions to be implemented are summarized below: Group 1: Control Group (CG; n: 10) Whey protein supplementation will be administered Vitamin and mineral supplementation will be administered No resistance exercise will be performed The participants will eat according to bariatric surgery nutrition guidelines and perform physical activities. Group 2: Whey Protein + Collagen + Exercise Group (WPCEG; n: 10) Whey protein supplements with collagen will be given. Vitamin and mineral supplements will be given. Resistance exercise will be performed. They will eat according to bariatric surgery nutrition guidelines and perform physical activities. They will begin a resistance exercise program 4 weeks after surgery. Group 3: Whey Protein + Collagen + No Exercise Group (WPCG; n: 10) Whey protein supplements with collagen will be given. Vitamin and mineral supplements will be given. No resistance exercise will be performed. They will eat according to bariatric surgery nutrition guidelines and perform physical activities. Group 4: Whey Protein + Exercise Group (WPEG; n: 10) Whey protein supplements will be given. Vitamin and mineral supplements will be given. Resistance exercise will be performed. They will eat according to bariatric surgery nutrition guidelines and perform physical activities. A resistance exercise program will begin at 4 weeks post-operatively.

Monitoring the Weight Evolution Using a Connected Scale

Current guideline recommend yearly multidisciplinary postoperative follow-up after bariatric surgery. However, practices remain very heterogeneous, and only a fraction of patients are still follow-up beyond two years after the operation. This study will assess a new care pathway in which the patients are follow-up according to the weight evolution measured by the patient using a connected scale.

Modified Thoracoabdominal Nerve Plane Block In Laparoscopic Sleeve Gastrectomy

Ultrasound-guided Modified Thoracoabdominal Nerve Plane Block (M-TAPA) is performed into the costochondral aspect at the 9th-10th costal level by injecting local anesthetics deep into the chondrium. It provides blockage of both the anterior and lateral cutaneous branches of the thoracoabdominal nerve. Studies show that M-TAPA block is effective for postoperative analgesia and other abdominal surgeries, but its effect on patients undergoing LSG surgery has not yet been studied. The hypothesis is that the M-TAPA block performed in patients undergoing Laparoscopic Sleeve Gastrectomy (LSG) Operation would reduce opioid consumption in the first 24 hours period after surgery.

Effects of the Dietary Inflammatory Index on Systemic Inflammation Markers and Gastrointestinal Symptoms in Individuals With Bariatric Surgery

The goal of this observational cross-sectional study is to evaluate the relationships between the Dietary Inflammatory Index (DII), systemic inflammatory markers, and gastrointestinal symptoms in adults aged 18-65 who have undergone bariatric surgery. The main questions it aims to answer are: Does the inflammatory potential of the diet affect systemic inflammation levels (such as SII, CRP, and WBC) in the post-operative period? Is there an association between the DII score and gastrointestinal symptoms (e.g., bloating, gas, abdominal pain)? Participants who are at least three months post-bariatric surgery will provide dietary intake data to calculate DII scores, undergo blood tests to measure inflammatory markers, and complete assessments regarding their gastrointestinal symptoms.

Tailored Stapled SADI-S: Initial Report and Preliminary Results

Obesity is a serious health problem worldwide and can lead to many diseases such as diabetes, high blood pressure, heart disease, and sleep apnea. When lifestyle changes and medications are not enough, metabolic and bariatric surgery (MBS) is currently the most effective and long-lasting treatment option. This study focuses on one of the newer types of bariatric surgery called Single Anastomosis Duodeno-Ileal Bypass with Sleeve Gastrectomy (SADI-S). This procedure combines two parts: Sleeve gastrectomy, which reduces the size of the stomach so the patient feels full after eating a small amount. Duodeno-ileal bypass, which shortens the path food takes through the small intestine to reduce calorie absorption. Our hospital's surgical team is studying a tailored version of this operation, where the length of the bypassed intestine is adjusted to each patient's anatomy. We believe this personalized approach may improve weight loss results while lowering the risk of vitamin and nutrient deficiencies. The study will include 40 adult patients with obesity who are undergoing SADI-S surgery, either as their first weight loss operation or as a revision surgery after an earlier sleeve gastrectomy. During the operation, surgeons will measure the total length of each patient's small intestine and use a formula to decide how much of it should be bypassed. The duodeno-ileal connection will be made using a stapled technique, which is expected to be safe and efficient. After surgery, patients will be followed regularly at 1, 3, 6, 9, and 12 months, and then once per year. At each visit, the study team will monitor weight loss, body mass index (BMI), resolution of diabetes and other obesity-related conditions, nutritional status (including vitamins and minerals), and any side effects such as diarrhea, reflux, or nutritional problems. The goal of this study is to learn whether this tailored SADI-S technique can provide strong, sustained weight loss and health improvement with fewer long-term complications. The results will help improve surgical planning for future patients by showing whether measuring and customizing the bypass length is safer and more effective than using a fixed length. All data collected will be kept confidential. Patients' participation in the study will not change their regular care or follow-up, and they can withdraw at any time without affecting their treatment.