Preoperative 4-week supplementation with omega-3 polyunsaturated fatty acids reduces liver volume and facilitates bariatric surgery in morbidly obese patients

Multi-omic network analysis identified betacellulin as a novel target of omega-3 fatty acid attenuation of western diet-induced nonalcoholic steatohepatitis

Clinical and preclinical studies established that supplementing diets with ω3 polyunsaturated fatty acids (PUFA) can reduce hepatic dysfunction in nonalcoholic steatohepatitis (NASH) but molecular underpinnings of this action were elusive. Herein, we used multi-omic network analysis that unveiled critical molecular pathways involved in ω3 PUFA effects in a preclinical mouse model of western diet induced NASH. Since NASH is a precursor of liver cancer, we also performed meta-analysis of human liver cancer transcriptomes that uncovered betacellulin as a key EGFR-binding protein upregulated in liver cancer and downregulated by ω3 PUFAs in animals and humans with NASH. We then confirmed that betacellulin acts by promoting proliferation of quiescent hepatic stellate cells, inducing transforming growth factor-β2 and increasing collagen production. When used in combination with TLR2/4 agonists, betacellulin upregulated integrins in macrophages thereby potentiating inflammation and fibrosis. Taken together, our results suggest that suppression of betacellulin is one of the key mechanisms associated with anti-inflammatory and anti-fibrotic effects of ω3 PUFA on NASH.

Nutrition, Physical Activity, and Prescription of Supplements in Pre- and Post-bariatric Surgery Patients: An Updated Comprehensive Practical Guideline

Only in the USA, 315 billion dollars are spent annually on the medical cost of obesity in adult patients. Till now, bariatric surgery is the most effective method for treating obesity and can play an essential role in reducing the direct and indirect costs of obesity treatment. Nonetheless, there are few comprehensive guidelines which include nutrition, physical activity, and supplements, before and after surgery. The purpose of the present narrative review is to provide an updated and comprehensive practical guideline to help multidisciplinary teams. The core keywords include nutrition, diet, physical activity, exercise, supplements, macronutrients, micronutrients, weight reduction, bariatric surgery, Roux-en-Y Gastric Bypass, Sleeve Gastrostomy, Laparoscopic Adjustable Gastric Banding, and Biliopancreatic diversion with duodenal switch which were searched in databases including PubMed/Medline, Cochrane, and some other sources such as Google Scholar. We answered questions in five important areas: (a) nutritional strategies before bariatric surgery, (b) nutrition after bariatric surgery, (c) physical activity before and after bariatric surgery, (d) weight regain after bariatric surgery, and (e) micronutrient assessments and recommendations before and after bariatric surgery. Some new items were added in this updated guideline including "weight regain" and "pregnancy after bariatric surgery." Other fields were updated based on new evidence and guidelines.

Oral ω-3 PUFA supplementation modulates inflammation in adipose tissue depots in morbidly obese women: A randomized trial

OBJECTIVES

Obesity is characterized by local and systemic low-grade inflammatory responses. Adipose tissue macrophages (ATM) play decisive roles in inflammation, insulin signaling, and various metabolic dysfunctions. Diets enriched with ω-3 polyunsaturated fatty acids (PUFAs) have been shown to improve health and mitigate pathologic conditions. However, the effects of ω-3 PUFA on adipose tissue inflammation, ATM number, and phenotype are poorly defined in human obesity. The aim of this study was to examine differences in expression of metabolic-inflammatory markers in omental, mesenteric, and subcutaneous fat depots of obese women supplemented with ω-3 PUFAs for 4 wk compared with a low-calorie diet before bariatric surgery.

METHODS

In a randomized controlled trial, inflammatory markers in the abdominal adipose tissue and the systemic response in obese women were studied. Patients were treated with a 2-wk low-calorie diet (LCD) or a 4-wk ω-3 PUFA-enriched diet (920 mg eicosapentaenoic acid, 760 mg docosahexaenoic acid daily) before laparoscopic bypass surgery. Omental, mesenteric, and subcutaneous adipose tissue biopsies were collected during surgery and analyzed for quantity and phenotype of ATMs, and profiled for adipokines, cytokines, and signal transduction molecules.

RESULTS

The chronic inflammatory state characterized by ATM markers was mostly improved by ω-3 PUFAs in visceral adipose tissue. We observed a decreased expression of CD45, CCL2, and CD68, indicating a lower inflammatory state. In patients with type 2 diabetes, ω-3 PUFAs lowered the expression of Netrin-1.

CONCLUSIONS

Compared with an LCD, a diet enriched with ω-3 PUFAs influences the inflammatory state in different adipose tissue depots, by affecting markers of adipose tissue inflammation, macrophage phenotype, and retention. However, this was not reflected in clinical parameters such as insulin resistance and inflammatory cytokines. Subcutaneous adipose tissue and visceral adipose tissue have different responses to an LCD or a ω-3 PUFA-enriched diet. The presence of diabetes modifies the expression of inflammatory markers.

Effect of silymarin on liver size and nonalcoholic fatty liver disease in morbidly obese patients: A randomized double-blind clinical trial

BACKGROUND

A large liver size is a factor that may increase the difficulty of bariatric surgery (BS) and unwanted complications. Some agents have been used to decrease the liver size before BS. Silymarin has been used as an antioxidant agent to improve liver function tests. This study was designed to evaluate the effects of silymarin on liver dimensions, function, and lipid profile.

MATERIALS AND METHODS

A double-blind randomized clinical trial was performed on 56 patients. The patients were divided into silymarin and placebo groups. Blood samples and sonographic examinations were taken from the patients before and 4 weeks after the administration of the silymarin or placebo. In the first group, 140 mg silymarin was prescribed every 8 h for 4 weeks, and the other group received placebo in the same way with the same tablet shape. After the completion of the 4-week treatment, laboratory tests and ultrasonography were carried out again.

RESULTS

Thirty-nine (69.6%) patients were female with a mean body mass index (BMI) of 46.2 kg/m² and a mean age of 36.8 years. Most of the patients had a compliance of 80% and higher. The analysis did not show any significant difference in aspartate transaminase, alkaline transaminase, liver size, cholesterol, and triglyceride changes among the silymarin and placebo groups. BMI loss was slightly higher in the silymarin group although the difference was not statistically significant.

CONCLUSION

The present findings show that silymarin administration for 4 weeks does not affect liver size and function, but further evaluations should be carried out on the subject.

Impact of SARS-CoV-2 Lockdown on the Preoperative Care Program of Patients Scheduled for Bariatric Surgery

Objectives: To evaluate the effect of the SARS-CoV-2 lockdown on dietary habits, body weight, left hepatic lobe volume, use of micronutrient supplements, micronutrient status, frequency of physical activity, and evolution of comorbidities in patients undergoing preoperative care for BS. Materials and Methods: We prospectively evaluated the dietary habits (including use of micronutrient supplements and frequency of physical activity) of 36 patients who were candidates for BS from March to May 2020; 7-day food dietary records, body weight, left hepatic lobe volume by ultrasound, micronutrient status, and evolution of comorbidities were assessed. Results: All patients completed the study. Of the participants, 44.4% (16/36), 47.2% (17/36), and 27.8% (10/36) followed the preoperative indications for vegetables, fruits, and legumes, respectively, whereas over 50% did not. Furthermore, 30.6% (11/36) and 55.6% (20/36) of participants followed the prescribed recommendations for carbohydrates/sweets products and alcohol, respectively. A total of 61.1% (22/36) of participants experienced new foods and new culinary preparations. In addition, at the time of the study, we found that only 11.1% (4/36) were engaged in prescribed physical activity and only 36.1% (13/36) were taking prescribed micronutrient supplements. Compared to the initial weight, we observed an increased body weight and body mass index (+4.9%, p = 0.115; +1.89%, p = 0.0692, respectively), and no improvement in left hepatic lobe volume, micronutrient status, or comorbidities was recorded for any patient in the anamnesis. Conclusions: Lockdown determined by the SARS-CoV-2 pandemic has negatively affected the preoperative program of BS candidates, resulting in a postponement to the resumption of bariatric surgical activity.

N-3 Polyunsaturated Fatty Acids and Their Lipid Mediators as A Potential Immune-Nutritional Intervention: A Molecular and Clinical View in Hepatic Disease and Other Non-Communicable Illnesses

In recent years, the beneficial effect of n-3 polyunsaturated fatty acids (n-3 PUFAs) intake on human health has been widely accepted in the field of immunonutrition. Today, we find a diversity of supplements based on n-3 PUFAs and/or minerals, vitamins and other substances. The main objective of this review is to discuss the importance of n-3 PUFAs and their derivatives on immunity and inflammatory status related to liver disease and other non-communicable illnesses. Based on the burden of liver diseases in 2019, more than two million people die from liver pathologies per year worldwide, because it is the organ most exposed to agents such as viruses, toxins and medications. Consequently, research conducted on n-3 PUFAs for liver disease has been gaining prominence with encouraging results, given that these fatty acids have anti-inflammatory and cytoprotective effects. In addition, it has been described that n-3 PUFAs are converted into a novel species of lipid intermediaries, specialized pro-resolving mediators (SPMs). At specific levels, SPMs improve the termination of inflammation as well as the repairing and regeneration of tissues, but they are deregulated in liver disease. Since evidence is still insufficient to carry out pharmacological trials to benefit the resolution of acute inflammation in non-communicable diseases, there remains a call for continuing preclinical and clinical research to better understand SPM actions and outcomes.

Depletion of Omega-3 Fatty Acids in RBCs and Changes of Inflammation Markers in Patients With Morbid Obesity Undergoing Gastric Bypass

BACKGROUND

Bariatric surgery is considered the most effective treatment for severe obesity. Despite this wide success, bariatric surgery is associated with increased risks of nutritional deficiencies.

OBJECTIVES

To examine whether Roux-en-Y-gastric bypass (RYGB) alters essential fatty acid (FA) status and inflammation markers.

METHODS

Subjects with obesity (n = 28; BMI > 40 kg/m2; mean age 48 years) were studied before and 1 year after RYGB. We collected blood samples before and 12 months after RYGB, and analyzed FA in RBCs and peripheral blood mononuclear cells (PBMC), and measured inflammation parameters in plasma. The proportion of total n-3 FAs was the primary outcome, while parameters related to other FAs and inflammation factors were the secondary parameters. In addition, PBMCs from 15 of the participants were cultured alone or with 100 and 200 μM DHA, and the production of IL-6, IL-1β, PGE2, and prostaglandin F2-alpha (PGF2α) was assayed after endotoxin (LPS) stimulation.

RESULTS

RYGB induced a significant reduction of BMI (-30%) and improvement of insulin resistance (-49%). While the proportion of arachidonic acid was 15% higher after RYGB, the proportions of total and individual n-3 FAs were 50%-75% lower (P < 0.01). Consequently, the RBC omega-3 index and n-3:n-6 fatty acid ratio were 45% and 50% lower after surgery, respectively. In isolated PBMCs, LPS induced the production of IL-6, IL-1β, PGE2, and PGF2α in both pre- and post-RYGB cells, but the effects were 34%-65% higher (P < 0.05) after RYGB. This effect was abrogated by DHA supplementation.

CONCLUSIONS

This study presents evidence that RBC and PBMC n-3 FAs are severely reduced in patients with obesity after RYGB. DHA supplementation in PBMC moderates the production of inflammation markers, suggesting that n-3 FA supplementation would merit a trial in bariatric patients.

Perioperative omega-3 fatty acids for liver surgery: A meta-analysis of randomized controlled trials

INTRODUCTION

The effect of perioperative omega-3 fatty acids for liver surgery remained controversial. We conducted a systematic review and meta-analysis to explore the influence of omega-3 fatty acids versus placebo in patients undergoing liver surgery.

METHODS

We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through May 2020, and included randomized controlled trials (RCTs) assessing the effect of omega-3 fatty acids versus placebo for liver surgery. This meta-analysis was performed using the random-effect model.

RESULTS

Five RCTs were included in the meta-analysis. Overall, compared with control group for liver surgery, omega-3 fatty acids were associated with substantially reduced incidence of infection (odd ratio [OR]=0.56; 95% confidence interval [CI] =0.34-0.91; P = .02), but revealed no remarkable influence on complications (OR = 0.60; 95% CI = 0.29-1.24; P = .17), mortality (OR = 0.76; 95% CI = 0.06-9.37; P = .83), liver failure (OR = 0.72; 95% CI = 0.10 to 5.00; P = 0.74), biliary leakage (OR=1.24; 95% CI = 0.41 to 3.76; P = .70), bleeding (OR = 1.76; 95% CI = 0.63-4.95; P = .28), or ileus (OR = 0.39; 95% CI = 0.07-2.05; P = .27).

CONCLUSION

Perioperative omega-3 fatty acids may be beneficial to reduce the incidence of infection after liver surgery.

Nutrition, Physical Activity, and Prescription of Supplements in Pre- and Post-bariatric Surgery Patients: a Practical Guideline

According to ASMBS, the rate of bariatric surgery increased from 158,000 in 2011 to 196,000 in 2015. Nevertheless, this growth in invasive techniques does not eliminate unhealthy habits, so lifestyle modification such as healthy nutrition and correct physical activity programs may improve surgical results. The objective of the present narrative review was to categorize the guidelines related to nutrition, physical activity, and supplement prescription before and after bariatric surgery. The main key words including nutrition, diet, physical activity, exercise, supplements, macronutrients, micronutrients, weight reduction, bariatric surgery, Roux-en-Y gastric bypass, sleeve gastrostomy, laparoscopic adjustable gastric banding, and biliopancreatic diversion with duodenal switch were searched in databases including PubMed/Medline, Cochrane, and some other sources such as Google scholar. The recommendations are classified based on the type of surgery. The indications for surgery and the type of bariatric surgery are not included in this review. This review helps medical teams, including bariatric surgeons, nutritionists, and sports medicine specialists, with proper management before and after bariatric surgery.

Perioperative omega-3 fatty acids fail to confer protection in liver surgery: Results of a multicentric, double-blind, randomized controlled trial

BACKGROUND & AIMS

In a variety of animal models, omega-3 polyunsaturated fatty acids (Ω3-FAs) conferred strong protective effects, alleviating hepatic ischemia/reperfusion injury and steatosis, as well as enhancing regeneration after major tissue loss. Given these benefits along with its safety profile, we hypothesized that perioperative administration of Ω3-FAs in patients undergoing liver surgery may ameliorate the postoperative course. The aim of this study was to investigate the perioperative use of Ω3-FAs to reduce postoperative complications after liver surgery.

METHODS

Between July 2013 and July 2018, we carried out a multicentric, double-blind, randomized, placebo-controlled trial designed to test whether 2 single intravenous infusions of Omegaven® (Ω3-FAs) vs. placebo may decrease morbidity. The primary endpoints were postoperative complications by severity (Clavien-Dindo classification) integrated within the comprehensive complication index (CCI).

RESULTS

A total of 261 patients (132 in the Omegaven and 129 in the placebo groups) from 3 centers were included in the trial. Most cases (87%, n = 227) underwent open liver surgery and 56% (n = 105) were major resections (≥3 segments). In an intention-to-treat analysis including the dropout cases, the mortality rate was 4% and 2% in the Omegaven and placebo groups (odds ratio0.40;95% CI 0.04-2.51; p = 0.447), respectively. Any complications and major complications (Clavien-Dindo ≥ 3b) occurred in 46% vs. 43% (p = 0.709) and 12% vs. 10% (p = 0.69) in the Omegaven and placebo groups, respectively. The mean CCI was 17 (±23) vs.14 (±20) (p = 0.417). An analysis excluding the dropouts provided similar results.

CONCLUSIONS

The routine perioperative use of 2 single doses of intravenous Ω3-FAs (100 ml Omegaven) cannot be recommended in patients undergoing liver surgery (Grade A recommendation).

LAY SUMMARY

Despite strong evidence of omega-3 fatty acids having liver-directed, anti-inflammatory and pro-regenerative action in various rodent models, 2 single omega-3 fatty acid infusions given to patients before and during liver surgery failed to reduce complications. Because single omega-3 fatty acid infusions failed to confer liver protection in this trial, they cannot currently be recommended.

TRIAL REGISTRATION

ClinicalTrial.gov: ID: NCT01884948; Institution Ethical Board Approval: KEK-ZH-Nr. 2010-0038; Swissmedic Notification: 2012DR3215.

Perioperative care of the obese patient

Background

Obesity has become an increasing problem worldwide during the past few decades. Hence, surgeons and anaesthetists will care for an increasing number of obese patients in the foreseeable future, and should be prepared to provide optimal management for these individuals. This review provides an update of recent evidence regarding perioperative strategies for obese patients.

Methods

A search for papers on the perioperative care of obese patients (English language only) was performed in July 2019 using the PubMed, Scopus, Web of Science and Cochrane Library electronic databases. The review focused on the results of RCTs, although observational studies, meta-analyses, reviews, guidelines and other reports discussing the perioperative care of obese patients were also considered. When data from obese patients were not available, relevant data from non-obese populations were used.

Results and conclusion

Obese patients require comprehensive preoperative evaluation. Experienced medical teams, appropriate equipment and monitoring, careful anaesthetic management, and an adequate perioperative ventilation strategy may improve postoperative outcomes. Additional perioperative precautions are necessary in patients with severe morbid obesity, metabolic syndrome, untreated or severe obstructive sleep apnoea syndrome, or obesity hypoventilation syndrome; patients receiving home ventilatory support or postoperative opioid therapy; and obese patients undergoing open operations, long procedures or revisional surgery.

A 4-Week Preoperative Ketogenic Micronutrient-Enriched Diet Is Effective in Reducing Body Weight, Left Hepatic Lobe Volume, and Micronutrient Deficiencies in Patients Undergoing Bariatric Surgery: a Prospective Pilot Study

BACKGROUND

Before bariatric surgery (BS), moderate weight loss, left hepatic lobe volume reduction, and micronutrient deficiency (MD) identification and correction are desirable.

OBJECTIVES

The objective of this study was to assess the safety and the effectiveness of a 4-week preoperative ketogenic micronutrient-enriched diet (KMED) in reducing body weight (BW), left hepatic lobe volume, and correcting MD in patients scheduled for BS.

MATERIALS AND METHODS

In this prospective pilot study, a cohort of morbidly obese patients (n = 27, 17 females, 10 males) with a mean body mass index (BMI) of 45.2 kg/m² scheduled for BS underwent a 4-week preoperative KMED. Their BW, BMI, fat mass (FM), fat-free mass (FFM), resting metabolic rate (RMR), left hepatic lobe volume, micronutrient status, and biochemical and metabolic patterns were measured before and after the 4-week KMED. Patient compliance was assessed by validated questionnaires (3-day estimated food records and 72-h recall). Qualitative methods (5-point Likert questionnaire) were used to measure diet acceptability and side effects.

RESULTS

All patients completed the study. We observed highly significant decreases in BW (- 10.3%, p < 0.001, in males; - 8.2%, p < 0.001, in females), left hepatic lobe volume (- 19.8%, p < 0.001), and an amelioration of patient micronutrient status. All patients showed a high frequency of acceptability and compliance in following the diet. No adverse side effect was reported.

CONCLUSION

This study demonstrates that a 4-week preoperative KMED is safe and effective in reducing BW, left hepatic lobe volume, and correcting MD in obese patients scheduled for BS.

How bariatric surgery affects liver volume and fat density in NAFLD patients

INTRODUCTION

Nonalcoholic fatty liver disease (NAFLD) is an epidemic in the obese population. Bariatric surgery is known to reverse multiple metabolic complications of obesity such as diabetes, dyslipidemia, and NAFLD, but the timing of liver changes has not been well described.

MATERIALS AND METHODS

This was an IRB-approved, two-institutional prospective study. Bariatric patients received MRIs at baseline and after a pre-operative liquid diet. Liver biopsies were performed during surgery and if NAFLD positive, the patients received MRIs at 1, 3, and 6 months. Liver volumes and proton-density fat fraction (PDFF) were calculated from offline MRI images. Primary outcomes were changes in weight, body mass index (BMI), percent excess weight loss (EWL%), liver volume, and PDFF. Resolution of steatosis, as defined as PDFF < 6.4% based on previously published cutoffs, was assessed. Secondarily, outcomes were compared between patients who underwent laparoscopic sleeve gastrectomy (LSG) versus laparoscopic Roux-en-Y gastric bypass (LRYGB).

RESULTS

From October 2010 to June 2015, 124 patients were recruited. 49 patients (39.5%) completed all five scans. EWL% at 6 months was 55.6 ± 19.0%. BMI decreased from 45.3 ± 5.9 to 34.4 ± 5.1 kg/m² and mean liver volume decreased from 2464.6 ± 619.4 to 1874.3 ± 387.8 cm³ with a volume change of 21.4 ± 11.4%. PDFF decreased from 16.6 ± 7.8 to 4.4 ± 3.4%. At 6 months, 83.7% patients had resolution of steatosis. Liver volume plateaued at 1 month, but PDFF and BMI continued to decrease. There were no statistically significant differences in liver volume or PDFF reduction from baseline to 6 months between the LSG versus LRYGB subgroups.

CONCLUSION

Patients with NAFLD undergoing bariatric surgery can expect significant decreases in liver volume and hepatic steatosis at 6 months, with 83.7% of patients achieving resolution of steatosis. Liver volume reduction plateaus 1-month post-bariatric surgery, but PDFF continues to decrease. LSG and LRYGB did not differ in efficacy for inducing regression of hepatosteatosis.

Preoperative Methods to Reduce Liver Volume in Bariatric Surgery: a Systematic Review

Background

Patients qualified for gastric bypass surgery have an enlarged and fatty liver. An essential step in gastric bypass surgery is elevation of the left liver lobe to expose the gastroesophageal junction. An enlarged and fatty liver complicates the surgical procedure and increases the risk for laceration of the liver. The aim of our study was to evaluate methods to reduce liver volume in patients prior to gastric bypass surgery.

Methods

A systematic literature search of multiple databases, including PubMed, EMBASE.com, and the Cochrane Library and a hand search of reference lists, was performed. We used the search terms morbid obesity and liver, including their synonyms and controlled terms. Inclusion criteria were as follows: patients with morbid obesity who qualified for bariatric surgery, the use of a preoperative treatment to reduce liver volume, and the use of imaging techniques before and after treatment.

Results

In total, 281 patients in 11 different studies were included. Preoperative diets reduced liver size by an average of 14 %, alternative methods including nutritional supplements, reduced liver size between 20 and 43 %, and an intragastric balloon by 32 %.

Conclusions

This review showed that nutritional supplements and intragastric balloon are more effective than low calorie diets in reducing liver volume prior to gastric bypass surgery. However, low calorie diet is the preferable method to reduce liver volume, considering the level of evidence and practical applicability. There is a need for well-designed randomized studies with sufficient power in order to confirm the effectiveness of preoperative methods to reduce liver volume.

Obesity and colorectal liver metastases: Mechanisms and management

INTRODUCTION

Colorectal cancer (CRC) is the third commonest malignancy after lung and breast cancer. The most common cause of mortality from CRC is from distant metastases. Obesity is a known risk factor for primary CRC development. However, its role in metastatic disease progression is not fully understood. The article aims to provide an overview of the role of obesity in colorectal liver metastases (CRLM). Furthermore, possible strategies to minimise this effect are discussed. An electronic search of MedLine, EMBASE, CINAHL and google scholar was performed. Relevant articles were included in the article. Obesity causes localised inflammation within the liver microenvironment which may predispose to metastases development. Furthermore, obesity causes systemic inflammation leading to release of protumourigenic growth factors. Several studies demonstrated the effects of lifestyle modification, medications, bariatric surgery and omega-3 fatty acids on steatosis within the context of liver surgery. It is currently unclear whether obesity directly leads to metastatic disease via chronic systemic inflammation or whether obesity induced steatosis provides a fertile microenvironment for metastases deposition. With a global increase in obesity useful strategies to minimise the effects of obesity on the liver include life-style modification, pre-operative dietary regimes and omega-3 fatty acids intake. Pre-operative optimisation of the patient is a key concept. Further randomised control trials are needed to guide management strategies.

What to do when it is technically impossible to perform laparoscopic sleeve gastrectomy

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) is increasingly popular with surgeons because of its apparent technical ease. However, performing LSG safely is sometimes not possible during laparoscopy. The objectives of the present study were to (i) describe the context of LSG failure and (ii) suggest preoperative care options or strategies that enable secondary LSG to be performed safely.

METHODS

We studied patients having undergone primary and secondary LSG between January 2008 and July 2013. The primary efficacy criterion was the LSG success rate. The secondary efficacy criteria were preoperative care procedures, the complication rate, the failure rate, and the frequency of conversion to open surgery.

RESULTS

During the study period, 954 patients underwent first- or second-line LSG. Laparoscopic sleeve gastrectomy was technically impossible in 12 patients (1.2 %). The cause of failure was a large left liver lobe in seven cases (58.3 %) and a lack of space in five cases. Of these 12 patients, nine underwent secondary LSG. The median preoperative BMI before the first LSG was 51.5 kg/m(2). The median (range) time interval between the two LSG attempts was 6 months (3-37). Prior to secondary LSG, the preoperative weight reduction measure was a diet in seven cases (78 %), an intragastric balloon in one case, and no treatment in one case. The median preoperative excess weight loss (EWL) before the second LSG was 10 % (0-20). Five LSGs were successful, two required conversion to open surgery, and two failed again. There were two postoperative complications (22 %), both of which concerned the two patients with conversion to laparotomy.

CONCLUSIONS

In the event of LSG technical failure, preoperative weight loss may enable a second attempt at laparoscopic treatment. A preoperative EWL of at least 10 % appears to be required for the avoidance of conversion to laparotomy.

Clinical impact of Mediterranean-enriched-protein diet on liver size, visceral fat, fat mass, and fat-free mass in patients undergoing sleeve gastrectomy

BACKGROUND

Weight loss before laparoscopic sleeve gastrectomy (LSG) is desirable because it can reduce visceral fat and liver size thereby facilitating the surgical procedure. Preoperative very-low-energy diets have been demonstrated to decrease weight, visceral fat, and liver size. However, no studies have been conducted using the Mediterranean-protein-enriched diet (MPED) or on the amount of preoperative weight loss attributed to the loss of fat-free mass (FFM).

OBJECTIVES

To evaluate the effect of the MPED on weight, visceral fat, liver size, fat mass (FM), and FFM in obese patients undergoing LSG.

SETTING

University Hospital, Italy.

MATERIALS AND METHODS

Obese male patients (n = 37) with a mean body mass index (BMI) of 45.2 kg/m(2) scheduled for LSG underwent an 8-week preoperative MPED. Their weight, visceral fat, body composition, liver size, and biochemical and metabolic patterns were measured before and after the diet. Patient compliance was assessed by the presence of ketonuria and weight loss. Qualitative methods (5-point Likert questionnaire) were used to measure diet acceptability and side effects.

RESULTS

We observed highly significant decreases in weight, liver size, visceral fat, and FM; however, there was no significant reduction in FFM. All tested patients showed a high frequency of acceptability and compliance in following the diet, and no secondary effects were observed.

CONCLUSION

Based on our findings, we were able to support the hypothesis that MPED might be associated with significant reductions in weight loss, FM, and liver size without a significant loss of FFM.