Ramon Vilallonga

• MD. PhD
• Head Endocrine-Metabolic and Bariatric Surgery Unit. Vall Hebron Barcelona Hospital Campus. at Vall d'Hebron Institut de Recerca

Global obesity rates have risen dramatically, now exceeding deaths from starvation. Metabolic and bariatric surgery (MBS), initially for severe obesity (BMI ≥35 kg/m 2), is performed globally over 500 000 times annually, offering significant metabolic benefits beyond weight loss. However, varying eligibility criteria globally impact patient care an...

Background The impact of bariatric surgery (BS) on the performance of 1mg Dexamethasone suppression test (DST) is not well established. Objective (1) To evaluate the intraindividual results of the DST in a group of patients before and 2 years after BS, and (2) to assess plasma dexamethasone levels and other factors influencing the reliability of t...

Artificial intelligence (AI) is transforming the landscape of medicine, including surgical science and practice. The evolution of AI from rule-based systems to advanced machine learning and deep learning algorithms has opened new avenues for its application in metabolic and bariatric surgery (MBS). AI has the potential to enhance various aspects of...

Bariatric and metabolic surgeries have gained extensive popularity and trust due to their documented efficacy and safety in managing not only obesity but also associated comorbidities such as diabetes mellitus, hypertension, dyslip-idemia, sleep apnea, and joint pain. Traditionally, bariatric surgeries have been categorized into hypoabsorptive, res...

Background Intraoperative neuromonitoring (IONM) of the recurrent laryngeal nerve (RLN) aims to detect and prevent iatrogenic damage during thyroid surgery. Mechanisms of injury include traction, heat damage, and nerve transection. Continuous IONM (C‐IONM) techniques detect impending damage due to traction and heat related when they are still rever...

Background: Bariatric surgery (BS) is effective for achieving significant weight loss. However, weight regain (WR) is an emerging problem. Objective: To assess the prognostic value of morning serum cortisol, a 1 mg dexamethasone suppression test (DST), 24 h urinary free cortisol (UFC) and late-night salivary cortisol (LNSC) in a cohort of patients...

Background: The diet and physical activity of the world’s population determine the increase in the number of bariatric surgeries. The most common types of bariatric surgery are laparoscopic sleeve gastrectomy (LSG) and Roux-Y gastric bypass (RYGB). Surgical interventions are carried out in patients with numerous comorbidities, among which the most...

Purpose With the global epidemic of obesity, the importance of metabolic and bariatric surgery (MBS) is greater than ever before. Performing these surgeries requires academic training and the completion of a dedicated fellowship training program. This study aimed to develop guidelines based on expert consensus using a modified Delphi method to crea...

Purpose There is a lack of evidence for treatment of some conditions including complication management, suboptimal initial weight loss, recurrent weight gain, or worsening of a significant obesity complication after one anastomosis gastric bypass (OAGB). This study was designed to respond to the existing lack of agreement and to provide a valuable...

The laryngeal adductor reflex (LAR) is a brainstem reflex that closes the vocal fold and constitutes a new method for continuously monitoring the vagus and laryngeal nerves during different surgeries. Previous reports concluded that topical lidocaine in spray inhibited LAR responses. However, topical anesthesia in the upper airway may be necessary...

This study aimed to survey international experts in metabolic and bariatric surgery (MBS) to improve and consolidate the management of biliary disease in patients with severe obesity undergoing MBS. Obesity and rapid weight loss after MBS are risk factors for the development of gallstones. Complications, such as cholecystitis, acute cholangitis, an...

Obesity is now recognized as a chronic disease associated with a pro-inflammatory state and is often undertreated. It has become a global epidemic, affecting populations worldwide1,2. Metabolic and bariatric surgery (MBS) is considered the most effective treatment option for obesity, which is a chronic, relapsing, and progressive disease3. These su...

Metabolic and bariatric surgery (MBS) is the preferred method to achieve significant weight loss in patients with Obesity Class V (BMI > 60 kg/m2). However, there is no consensus regarding the best procedure(s) for this population. Additionally, these patients will likely have a higher risk of complications and mortality. The aim of this study was...

Obesity is a growing global health problem, and currently, bariatric surgery (BS) is the best solution in terms of sustained total weight loss (TWL). However, a significant number of patients present weight regain (WR) in time. There is a lack of biomarkers predicting the response to BS and WR during the follow-up. Plasma SHBG levels, which are low...

Background Whether the benefits of the robotic platform in bariatric surgery translate into superior surgical outcomes remains unclear. The aim of this retrospective study was to establish the ‘best possible’ outcomes for robotic bariatric surgery and compare them with the established laparoscopic benchmarks. Methods Benchmark cut-offs were establ...

Introduction: Robotic bariatric surgery (RBS) has seen a surge in popularity in recent years, yet questions persist about its utility concerning postoperative complications, costs, and technical aspects. RBS, while increasing in number, presents a greater technical challenge associated with more post-operative complications compared to primary bari...

Background Metabolic and bariatric surgery (MBS) in patients with low body mass index patients is a topic of debate. This study aimed to address all aspects of controversies in these patients by using a worldwide survey. Methods An online 35-item questionnaire survey based on existing controversies surrounding MBS in class 1 obesity was created by...

Performing a digestive anastomosis is a challenging task, especially the duodenoileal anastomosis of the duodenal switch. A leak may have very serious consequences in terms of severe morbidity or even death. For this reason, it is very important to perform an adequate leak test after the completion of the anastomosis. Methylene blue test, indocyani...

Background: Shared decision-making (SDM) between clinicians and patients is one of the pillars of the modern patient-centric philosophy of care. This study aims to explore SDM in the discipline of trauma and emergency surgery, investigating its interpretation as well as the barriers and facilitators for its implementation among surgeons. Methods:...

Introduction: Despite the unanimous acknowledgement of the laparoscopic sleeve gastrectomy (LSG) worldwide, the leak remains its deficiency. For the last decade, the surgical treatment was practically considered mandatory for almost any collection following LSG. The aim of this study is to evaluate the need for surgical drainage for leak following...

Background: Laparoscopic adjustable gastric band (LAGB) procedures have declined worldwide in recent years. A known complication is the intraluminal erosion of the prosthetic material. The endoscopic management of gastric band erosion represents the recommended approach nowadays, and it avoids any additional trauma to the gastric wall already dama...

Purpose: The present research was conducted to evaluate the effect of the severity of dumping syndrome (DS) on weight loss outcomes after Roux-en-Y gastric bypass (RYGB) in patients with class III obesity. Methods: The present retrospective cohort study used the dumping symptom rating scale (DSRS) to evaluate the severity of DS and its correlati...

Background: Artificial intelligence (AI) is gaining traction in medicine and surgery. AI-based applications can offer tools to examine high-volume data to inform predictive analytics that supports complex decision-making processes. Time-sensitive trauma and emergency contexts are often challenging. The study aims to investigate trauma and emergenc...

(1) Background: The current criteria for defining good or bad responders to bariatric surgery based on the percentage of weight loss do not properly reflect the therapeutic impact of the main bariatric techniques. At present there is an urgent need to fill this gap and provide scientific evidence that better define the success or failure of bariatr...

Background Gastroesophageal reflux disease (GERD) is one of the most common diseases in North America and globally. The aim of this guideline is to provide evidence-based recommendations regarding the most utilized and available endoscopic and surgical treatments for GERD.Methods Systematic literature reviews were conducted for 4 key questions rega...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Introduction: A significant reduction in fat-free mass (FFM) following bariatric surgery (BS) has been reported, and adequate protein intake is recommended for FFM preservation. Current guidelines of nutritional management after BS recommend complex protein (CP) compounds. However, Roux-en-Y-gastric bypass (RYGB) has a negative impact on CP digest...

PurposeThus far, little attention has been paid to bariatric surgery (BS) in patients with severe obesity (SO) and cirrhosis with portal hypertension (PH). To address this knowledge gap, we systematically reviewed the available literature and evidence about BS in patients with SO and cirrhosis with PH. We inform on the perioperative and long-term o...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The coronavirus disease 2019 (COVID-19) pandemic led to a worldwide suspension of bariatric and metabolic surgery (BMS) services. The current study analyses data on patterns of service delivery, recovery of practices, and protective measures taken during the COVID-19 pandemic by bariatric teams. Materials and Methods The current study is...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The 2015 Lancet Commission on global surgery identified surgery and anaesthesia as indispensable parts of holistic health-care systems. However, COVID-19 exposed the fragility of planned surgical services around the world, which have also been neglected in pandemic recovery planning. This study aimed to develop and validate a novel index...

Background The coronavirus disease 2019 (COVID-19) pandemic led to a worldwide suspension of bariatric and metabolic surgery (BMS) services. The current study analyses data on patterns of service delivery, recovery of practices, and protective measures taken during the COVID-19 pandemic by bariatric teams. Materials and Methods The current study i...

Introduction: Recording every procedure could diminish the postoperative complication rates in bariatric surgery. The aim of our study was to evaluate the correlation between recording every bariatric surgery and their postoperative analysis in relation to the early or late postoperative complications. Methods: Seven hundred fifteen patients who...

Introduction Pylephlebitis represents an uncommon but serious condition with significant mortality which can complicate intrabdominal sepsis of any etiology. One of the most common predisposing infections is appendicitis. Presentation of case A 21-year-old male with 4 days of epigastric and right upper quadrant pain with associated fever and chill...

Roux-en-Y gastric bypass (RYGB) is an effective operation to treat morbidly obese patients, but weight loss is not sustainable for most patients. Such as revision or conversion surgeries, an alternative has been a single-anastomosis duodenoileal bypass with sleeve gastrectomy (SADI-S). Thus, this study addresses the description, feasibility, and ea...

Introduction Change in lifestyle and diets is a part of the bariatric surgery process. Preoperative weight loss is still considered obligatory in some programs, but its benefits remain controversial. This study aimed to evaluate the influence of the preoperative weight loss on the postoperative results, in terms of long-term weight loss and periope...

Background Bariatric surgery in patients with BMI over 50 kg/m ² is a challenging task. The aim of this study was to address main issues regarding perioperative management of these patients by using a worldwide survey. Methods An online 48-item questionnaire-based survey on perioperative management of patients with a BMI superior to 50 kg/m ² was...

Purpose One anastomosis/mini gastric bypass (OAGB/MGB) is up to date the third most performed obesity and metabolic procedure worldwide, which recently has been endorsed by ASMBS. The main criticisms are the risk of bile reflux, esophageal cancer, and malnutrition. Although IFSO has recognized this procedure, guidance is needed regarding selection...

Background Age ≥ 65 years is regarded as a relative contraindication for bariatric surgery. Advanced age is also a recognised risk factor for adverse outcomes with Coronavirus Disease-2019 (COVID-19) which continues to wreak havoc on global populations. This study aimed to assess the safety of bariatric surgery (BS) in this particular age group dur...

Purpose The effectiveness of enhanced recovery after surgery (ERAS) pathways in patients undergoing bariatric surgery remains unclear. Our objective was to determine the effect of the ERAS elements on patient outcomes following elective bariatric surgery. Materials and Methods Prospective cohort study in adult patients undergoing elective bariatri...

Introduction: Single-anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) is a recent bariatric surgery technique, highly effective in terms of weight loss. Nevertheless, data regarding the impact of SADI-S at mid-long term (after >5 years of follow-up) are scarce. Objectives: To evaluate the effect of lengths of common intestinal loop...

Purpose Bariatric surgery (BS) induces a significant and sustained weight loss in patients with severe obesity (SO). Nevertheless, apart from significantly reducing body fat, fat-free mass (FFM) might also be lost. At present, there is little and controversial data in the literature regarding the impact of BS on FFM. In recent years, bioimpedance (...

Purpose: Cholelithiasis is an issue in bariatric surgery patients. The incidence of cholelithiasis is increased in morbidly obese patients. After bariatric surgery, the management maybe sometimes challenging. There is no consensus about how to deal with cholelithiasis prior to bariatric surgery. Materials and methods: A retrospective review from...

This study compares laparoscopic RYGB (L-RYGB) and robotic RYGB (R-RYGB) performed by the same team after the learning curve in both approaches. A retrospective cohort study was done, and the surgical outcome was analyzed in 30 days and 12 months for patients with similar characteristics and an equal number of cases in each group (233 cases). Four...

Background The European Association for Endoscopic Surgery Bariatric Guidelines Group identified a gap in bariatric surgery recommendations with a structured, contextualized consideration of multiple bariatric interventions. Objective To provide evidence-informed, transparent and trustworthy recommendations on the use of sleeve gastrectomy, Roux-e...

Background: Metabolic and bariatric surgery (MBS) is an effective treatment for adolescents with severe obesity. Objectives: This study examined the safety of MBS in adolescents during the corona-virus disease 2019 (COVID-19) pandemic. Methods: This was a global, multicentre, and observational cohort study of MBS performed between May 01, 2020, and...

Introduction: Vertical banded gastroplasty (VBG) was a common bariatric procedure by laparotomy and or at the beginning of the laparoscopy, but nowadays it is almost an abandoned procedure. However, the young generation of bariatric surgeons should be aware about this procedure especially for revisional cases. Roux-en-Y gastric bypass (RYGB) is con...

Background Anastomotic leakage (AL) is one of the dreaded complications following surgery in the digestive tract. Near-infrared fluorescence (NIRF) imaging is a means to intraoperatively visualize anastomotic perfusion, facilitating fluorescence image-guided surgery (FIGS) with the purpose to reduce the incidence of AL. The aim of this study was to...

Background: Acute appendicitis is one of the most common causes of acute abdominal pain worldwide. Although several studies have tried to investigate effects of delayed appendectomy, robust recommendations on this topic are still lacking. The aim of this retrospective study was to evaluate the correlation between delayed surgical treatment in acute...

SARS-CoV-2 has been associated with an increased rate of venous thromboembolism in critically ill patients.Since surgical patients are already at higher risk of venous thromboembolism than general populations, thisstudy aimed to determine if patients with peri-operative or prior SARS-CoV-2 were at further increased risk ofvenous thromboembolism. We...

Background Major concerns years after the sleeve gastrectomy (SG) include weight regain, development of hiatal hernia (HH) and gastro esophageal reflux disease (GERD), with esophagitis and Barrett's esophagus (BE). Both problems could be related, and the incidence of asymptomatic patients is troubling. Goal To study the incidence of reflux symptom...

Around 30% of the patients that undergo bariatric surgery (BS) do not reach an appropriate weight loss. The OBEGEN study aimed to assess the added value of genetic testing to clinical variables in predicting weight loss after BS. A multicenter, retrospective, longitudinal, and observational study including 416 patients who underwent BS was conducte...

Background: After the first laparoscopic Roux-en-Y gastric bypass (RYGB) in 1994 by Wittgrove, the introduction of robot-assisted procedures was the next step in the surgical race to reduce invasiveness. This breakthrough allowed us to perform bariatric surgery with less surgical trauma in obese patients with metabolic disorders, producing an expon...

Background. Laparoscopic Roux-en-Y gastric bypass (GBP) is an essential bariatric surgical procedure which is globally performed because of the associated effective weight loss and resolution of metabolic comorbidities, such as diabetes and dyslipidemia. Although some complications may occur, hypoglycemia is a rare complication, which can lead to l...

Background There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus disease 2...

Purpose One major determinant of weight loss is resting energy expenditure (REE). However, data regarding REE is scarce in patients with severe obesity (SO)—BMI>50kg/m ² . Most studies used equation in order to estimate REE and not indirect calorimetry (IC) (gold standard). Additionally, there is no reliable data on the impact of bariatric surgery...

Laparoscopic sleeve gastrectomies (LSGs) can experience weight-loss failure and conversion to another bariatric procedure. An analysis of the bariatric literature concerning the single anastomosis duodeno-ileal bypass with sleeve gastrectomy (SADI-S) as revisional surgery after LSG in terms of safety and efficacy identified 607 studies. Fifty-nine...

Abstract Background There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus...

Abstract Background There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus...

Introduction: Obesity remains a major public chronic disease, and the multifactorial components of its relapse in many patients remain inevitable. Methods: This article provides a panoramic view of the most commonly performed revisional bariatric surgery (RBS). RBS is a complex procedure; thus, primary procedures should be well chosen and performed...

Background Sleeve gastrectomy (SG) has become one of the most performed bariatric procedures worldwide. Its main weaknesses are weight regain and gastroesophageal reflux disease (GERD). Conversion to Roux-en-Y gastric bypass (RYGB) is considered the gold standard to manage GERD and related symptoms. Methods Retrospective evaluation from a prospect...

Introduction: For the past 20 years, robotic surgical systems have been used for the Roux-en-Y gastric bypass (RYGB). The da Vinci Surgical System (Intuitive Surgical, Inc.) has been one of the most used robotic platforms. This study aims to retrospectively compare the performance of two models of surgical robots. Materials and Methods: A retrospec...

Background. Laparoscopic surgery generates end products that can have potentially harmful effects for the surgical team from short- or long-time exposure. In view of the current SARS-CoV-2 circumstances, controversy has risen concerning the safety of surgical smoke (SS) and aerosols and the perception of an increased risk of exposure during laparos...

Background There are data on the safety of cancer surgery and the efficacy of preventive strategies on the prevention of postoperative symptomatic COVID-19 in these patients. But there is little such data for any elective surgery. The main objectives of this study were to examine the safety of bariatric surgery (BS) during the coronavirus disease 2...

Background Nowadays, laparoscopic sleeve gastrectomy (LSG) is one of the most widely performed bariatric procedures. Different techniques have been described to reduce the rate of complications associated with the staple line, but no consensus has been reached.The aim of this study was to determine the incidence of surgical complications after LSG...

Background and Objectives: Bariatric surgery remains the gold standard treatment for morbidly obese patients. Roux-en-y gastric bypass and laparoscopic sleeve gastrectomy are the most frequently performed surgeries worldwide. Obesity has also been related to gastroesophageal reflux disease (GERD). The management of a preoperative diagnosis of GERD,...

Introduction: Roux-en-Y gastric bypass (RYGB) is the most common surgical procedure for morbid obesity. However, it can present serious late complications, like postprandial hyperinsulinemic hypoglycemia (PHH). Recent data suggested an increase in intestinal SGLT-1 after RYGB. However, there is no data on the inhibition of SGLT-1 to prevent PHH in...

Background and Objectives: The rising numbers of laparoscopic sleeve gastrectomy (LSG) procedures now being performed worldwide will likely be followed by an increasing number of patients experiencing gastro-esophageal reflux disease (GERD). The purpose of the current review was to analyze in terms of safety different techniques of fundoplication u...