Clinical application of laparoscopic bariatric surgery: an evidence-based review

BACKGROUND

Approximately one-third of U.S. adults are obese. Current evidence suggests that surgical therapies offer the morbidly obese the best hope for substantial and sustainable weight loss, with a resultant reduction in morbidity and mortality. Minimally invasive methods have altered the demand for bariatric procedures. However, no evidence-based clinical reviews yet exist to guide patients and surgeons in selecting the bariatric operation most applicable to a given situation.

METHODS

This evidenced-based review is presented in conjunction with a clinical practice guideline developed by the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES). References were reviewed by the authors and graded as to the level of evidence. Recommendations were developed and qualified by the level of supporting evidence available at the time of the associated SAGES guideline publication. The guideline also was reviewed and co-endorsed by the American Society for Metabolic and Bariatric Surgery.

RESULTS

Bariatric surgery is the most effective treatment for severe obesity, producing durable weight loss, improvement of comorbid conditions, and longer life. Patient selection algorithms should favor individual risk-benefit considerations over traditional anthropometric and demographic limits. Bariatric care should be delivered within credentialed multidisciplinary systems. Roux-en-Y gastric bypass (RGB), adjustable gastric banding (AGB), and biliopancreatic diversion with duodenal switch (BPD + DS) are validated procedures that may be performed laparoscopically. Laparoscopic sleeve gastrectomy (LSG) also is a promising procedure. Comparative data find that procedures with more dramatic clinical benefits carry greater risks, and those offering greater safety and flexibility are associated with less reliable efficacy.

CONCLUSIONS

Laparoscopic RGB, AGB, BPD + DS, and primary LSG have been proved effective. Currently, the choice of operation should be driven by patient and surgeon preferences, as well as by considerations regarding the relative importance placed on discrete outcomes.

High case volumes and surgical fellowships are associated with improved outcomes for bariatric surgery patients: a justification of current credentialing initiatives for practice and training

BACKGROUND

Recent years have seen the establishment of bariatric surgery credentialing processes, center-of-excellence programs, and fellowship training positions. The effects of center-of-excellence status and of the presence of training programs have not previously been examined. The objective of this study was to examine the effects of case volume, center-of-excellence status, and training programs on early outcomes of bariatric surgery.

STUDY DESIGN

Data were obtained from the Nationwide Inpatient Sample from 1998 to 2006. Quantification of patient comorbidities was made using the Charlson Index. Using logistic regression modeling, annual case volumes were analyzed for an association with each institution's center-of-excellence status and training program status. Risk-adjusted outcomes measures were calculated for these hospital-level parameters.

RESULTS

Data from 102,069 bariatric operations were obtained. Adjusting for comorbidities, greater bariatric case volume was associated with improvements in the incidence of total complications (odds ratio [OR] 0.99937 for each single case increase, p = 0.01), in-hospital mortality (OR 0.99717, p < 0.01), and most other complications. Hospitals with a Fellowship Council-affiliated gastrointestinal surgery training program were associated with risk-adjusted improvements in rates of splenectomy (OR 0.2853, p < 0.001) and bacterial pneumonias (OR 0.65898, p = 0.02). Center-of-excellence status, irrespective of the accrediting entity, had minimal independent association with outcomes. A surgical residency program had a varying association with outcomes.

CONCLUSIONS

The hypothesized positive volume-outcomes relationship of bariatric surgery is shown without arbitrarily categorizing hospitals to case volume groups, by analysis of volume as a continuous variable. Institutions with a dedicated fellowship training program have also been shown, in part, to be associated with improved outcomes. The concept of volume-dependent center-of-excellence programs is supported, although no independent association with the credentialing process is noted.

Sleeve Gastrectomy: Surgical Tips

The vertical sleeve gastrectomy is a bariatric procedure that was originally described as the initial step in the biliopancreatic diversion. It demonstrated effectiveness in weight loss as a single procedure, and the laparoscopic vertical sleeve gastrectomy, as a stand-alone procedure, is now the most commonly performed bariatric surgery worldwide. Due to its relative technical ease and long-term data that have established its durability in treating obesity and its related comorbid conditions, the sleeve gastrectomy has grown in popularity among patients and surgeons. While there are variations in the technical aspects of performing a laparoscopic sleeve gastrectomy, key steps must be undertaken to produce safe and effective outcomes. This article reviews the indications for bariatric surgery, patient selection, surgical technique and tips, perioperative care and complications after sleeve gastrectomy.

Risk-group targeted inferior vena cava filter placement in gastric bypass patients

BACKGROUND

Despite a growing body of evidence guiding appropriate perioperative thromboprophylaxis in the general population, few data direct strategies to reduce deep venous thrombosis (DVT) and pulmonary embolism (PE) in the morbidly obese. We have implemented a novel protocol for venous thromboembolism (VTE) risk stratification in Roux-en-Y gastric bypass (RYGB) candidates at our institution, which augments clinical assessment with screening for thrombophilias, to guide retrievable inferior vena cava (IVC) filter utilization.

METHODS

A retrospective review of prospectively collected data from patients who underwent primary RYGB between 2001 and 2008 at the University of North Carolina at Chapel Hill was completed. During that time, clinical assessment of VTE risk was amplified by focused plasma screening for common thrombophilias (factors VIII, IX, and XI, d-dimer, fibrinogen). Preoperative prophylactic IVC filters were offered to high-risk patients. The database was reviewed for perioperative DVTs, PEs, and filter-related complications.

RESULTS

Of 330 patients, in 162 attempts, 160 had prophylactic IVC filters placed with four complications overall (2.47%). No patient had symptoms of PE during the planned 6-week filter period, though one had a PE occur immediately after filter removal (0.63%); in contrast, five of 170 patients (2.94%) without prophylactic IVC filters presented with symptomatic PE (p = 0.216). In total, 147 (91.88%) prophylactic filters were removed.

CONCLUSIONS

Risk-group targeted prophylactic inferior vena cava filter placement prior to RYGB is safe with a trend towards reduced occurrence of PE.

Treatment Options and Outcomes for Celiac Artery Compression Syndrome

Background. Abdominal pain attributed to compression of the celiac artery at the level of the median arcuate ligament (MAL) of the diaphragm is an uncommon disorder. Although ultrasound investigation and arteriography can be suggestive of the diagnosis, no definitive criteria exist with only cases reports in the literature. This study presents the only known reported case series in which a combination of open and laparoscopic access techniques of MAL decompression are reported. Methods. A retrospective review of prospectively collected electronic databases of the University of North Carolina at Chapel Hill was performed for the period February 1999 until February 2009. Patients having undergone operation for celiac artery compression syndrome were identified and participated in a telephone interview. Questions were asked about the success of the operation, the recovery period, and patient satisfaction. Results. Six patients were identified, 3 were male; mean age was 37.7 years. Four underwent open MAL division and celiac ganglion neurolysis, and 2 underwent a laparoscopic approach. Mean follow-up was 48.6 months. All patients experienced symptomatic improvement and were satisfied with their outcome. No patient had symptoms recurrence. Conclusion. In this limited experience, MAL division with celiac ganglion neurolysis appears to be an effective treatment for celiac artery compression syndrome in appropriately selected patients. Both the open and laparoscopic approaches are safe with durable midterm follow-up results.

Prevalence of thrombophilias in patients presenting for bariatric surgery

BACKGROUND

The rise in bariatric surgery has driven an increased number of complications from venous thromboembolism (VTE). Evidence supports obesity as an independent risk factor for VTE, but the specific derangements underlying the hypercoagulability of obesity are not well defined. To better characterize VTE risk for the purpose of tailoring prophylactic strategies, we developed a protocol for thrombophilia screening in patients presenting for bariatric surgery at our institution.

METHODS

Between April 2004 and April 2006, 180 bariatric surgery candidates underwent serologic screening for inherited thrombophilias (Factor V-Leiden mutation, low Protein C activity, low Protein S activity, Free Protein S deficiency) and acquired thrombophilias (D-Dimer elevation, Fibrinogen elevation, elevation of coagulation factors VIII, IX, and XI, elevation of Lupus anticoagulants and homocysteine level, and Antithrombin III deficiency). Prevalence rate of each thrombophilia in the subject group was compared to the actual prevalence rate of the general population.

RESULTS

Most plasma markers of both inherited and acquired thrombophilias were identified in higher than expected proportions, including D-Dimer elevation in 31%, Fibrinogen elevation in 40%, Factor VIII elevation in 50%, Factor IX elevation in 64%, Factor XI elevation in 50%, and Lupus anticoagulant in 13%.

CONCLUSIONS

Obesity is a well-described demographic risk factor for VTE. In bariatric surgery candidates routinely screened for serologic markers, both inherited and acquired thrombophilias occurred more frequently than in the general population, and may therefore prove to be useful for individualized VTE risk assessment and prophylaxis.

Binge eating, body mass index, and gastrointestinal symptoms

OBJECTIVE

Symptoms of both gastroesophageal reflux disease (GERD) and irritable bowel syndrome (IBS) are frequently reported by individuals who binge eat. Higher body mass index (BMI) has also been associated with these disorders and with binge eating (BE). However, it is unknown whether BE influences GERD/IBS and how BMI might affect these associations. Thus, we examined the potential associations among BE, GERD, IBS, and BMI.

METHODS

Participants were from the Swedish Twin study of Adults: Genes and Environment (STAGE) and provided information on disordered eating behavior, BMI, gastrointestinal (GI) disorders, and commonly comorbid psychiatric and somatic illnesses. Key features of GERD and IBS were identified to create modified definitions of both disorders that were used as primary outcome variables. Logistic regression models were applied to determine the association between BE and each GERD/IBS both independently and in the context of BMI and other commonly comorbid psychiatric and somatic morbidities.

RESULTS

Prevalence estimates for GERD and IBS were higher among women than men (all p-values<.001). Only the association between BE and IBS was significant in both men and women after adjustment for BMI and the psychiatric/somatic morbidities.

CONCLUSION

BE appears to be an important consideration in the presence of IBS symptoms in both men and women, even when considering the impact of BMI and other commonly comorbid conditions. This association underscores the importance of routine assessment of BE in patients presenting with IBS to effectively manage the concurrent presentation of these problems.

Clinical spotlight review for the management of choledocholithiasis

Choledocholithiasis is a common presentation of symptomatic cholelithiasis that can result in biliary obstruction, cholangitis, and pancreatitis. A systematic English literature search was conducted in PubMed to determine the appropriate management strategies for choledocholithiasis. The following clinical spotlight review is meant to critically review the available evidence and provide recommendations for the work-up, investigations as well as the endoscopic, surgical and percutaneous techniques in the management of choledocholithiasis.

Specific hydraulic conductivity of corneal stroma as seen by quick-freeze/deep-etch

Previous studies of the hydraulic conductivity of connective tissues have failed to show a correspondence between ultrastructure and specific hydraulic conductivity. We used the technique of quick-freeze/deep-etch to examine the ultrastructure of the corneal stroma and then utilized morphometric studies to compute the specific hydraulic conductivity of the corneal stroma. Our studies demonstrated ultrastructural elements of the extracellular matrix of the corneal stroma that are not seen using conventional electron microscopic techniques. Furthermore, we found that these structures may be responsible for generating the high flow resistance characteristic of connective tissues. From analysis of micrographs corrected for depth-of-field effects, we used Carmen-Kozeny theory to bound a morphometrically determined specific hydraulic conductivity of the corneal stroma between 0.46 x 10(-14) and 10.3 x 10(-14) cm2. These bounds encompass experimentally measured values in the literature of 0.5 x 10(-14) to 2 x 10(-14) cm2. The largest source of uncertainty was due to the depth-of-field estimates that ranged from 15 to 51 nm; a better estimate would substantially reduce the uncertainty of these morphometrically determined values.

Evaluation of gastric fundus invagination for weight loss in a porcine model

Gastric fundus compliance allows stomach volume increase in response to food intake. Absence of this postprandial relaxation alters hormonal signals and induces early satiety and weight loss. This study demonstrates the effect of gastric fundus invagination on the growth rate of juvenile pigs. After institutional animal care and use committee approval, 15 juvenile pigs were divided into two groups. In the first group, six pigs were anesthetized, weighed, and submitted to laparotomy, stomach manipulation, and short gastric vessel ligation. This is the control group and is referred to as "Sham". In the second group, gastric fundus invagination was added by using a circular stapler. This is the procedure group and is designated as "GFI". Postoperatively, body weight and food intake were measured for 5 weeks. Pigs were euthanized and the stomachs examined. Growth patterns were compared. Three animals were excluded from the analysis. At the end of the 5-week study period, six GFI pigs had intact anastomosis with an invaginated fundus. The mean percent growth rate for the GFI group (54.2 ± 2.8 %) was significantly less than the Sham group (77.7 ± 4.9 %). Gastric fundus invagination significantly decreases the growth rate in juvenile pigs.

Central Venous Line Placement prior to Gastric Bypass Improves Operating Room Efficiency

Background. Bariatric surgery has increased across America. Venous access is difficult in these patients. Anesthesiologists often utilize valuable operating room (OR) time acquiring reliable intravenous lines. Our objective was to determine if outpatient central venous line (CVL) placement improves OR efficiency and professional reimbursement for CVL insertion. Methods. In our bariatric practice, selected surgery patients have outpatient CVLs placed during prophylactic vena cava filter placement. In a cohort of 268 gastric bypass patients operated between 1/01 and 11/06, we compared time-to-incision between 106 with pre-established CVLs and 162 without. In addition, we determined professional compensation rates for CVLs placed outpatient versus CVLs inserted in the OR. Results. Patients with preoperative (outpatient) CVLs required 35.6 ± 12.5 minutes to skin incision compared with 42.5 ± 13.9 minutes for controls (P < 0.0001), and 34.9% had skin incision in <30 minutes compared with 16.4% of controls. Radiologists collected 28.2% of outpatient billings for CPT code 36556, compared with anesthesiologists who collected <1% when placing CVLs in the OR. Conclusions. Outpatient CVLs prior to gastric bypass improve efficiency in the OR with earlier skin incision. Professional reimbursement is better for outpatient CVLs than intraoperative inpatient CVLs.

Bariatric surgery and relevant comorbidities: a systematic review and meta-analysis

BACKGROUND

Obesity is a growing epidemic in the United States, and with this, has come an increasing volume of metabolic surgery operations. The ideal management of obesity-associated medical conditions surrounding these operations is yet to be determined. This review sought to investigate the routine use of intraoperative cholangiogram (IOC) with cholecystectomy during or after a bypass-type operation, the ideal management of post-sleeve gastrectomy gastroesophageal reflux disease (GERD), and the optimal bariatric operation in patients with known inflammatory bowel disease (IBD).

METHODS

Using medical literature databases, searches were performed for randomized controlled trials (RCTs) and non-randomized comparative studies from 1990 to 2022. Each study was screened by two independent reviewers from the SAGES Guidelines Committee for eligibility. Data were extracted while assessing the risk of bias using the Cochrane Risk of Bias 2.0 Tool and the Newcastle-Ottawa Scale for RCTs and cohort studies, respectively. A meta-analysis was performed using random effects.

RESULTS

Routine use of IOC was associated with a significantly decreased rate of common bile duct injury and a trend towards decreased intraoperative complications, perioperative complications, and mortality. The rates of reoperation, postoperative pancreatitis, cholangitis, and choledocholithiasis were low in the routine use of the IOC group, but no non-routine use studies evaluated these outcomes. After sleeve gastrectomy, GERD-specific quality of life was significantly higher in the surgically treated group compared to the medically treated group. Bypass-type operations had worse outcomes of IBD sequelae than sleeve gastrectomy, including pain, patient perception, and fistula formation. Sleeve patients had lower mortality and fewer short- and long-term complications.

CONCLUSIONS

Low-quality data limited the conclusions that were drawn; however, trends were observed favoring the routine use of IOC during cholecystectomy for patients with bypass-type anatomy, surgical treatment of GERD post-sleeve gastrectomy, and sleeve gastrectomy in IBD patients. Future research proposals are suggested to further answer the questions posed.

Reduced Survival in Bariatric Surgery Candidates Delayed or Denied by Lack of Insurance Approval

Bariatric surgery reduces mortality for Americans who meet candidacy criteria and have insurance coverage. Unfortunately, some medically suitable candidates are denied or delayed during insurance approval processes. The long-term impact of such care delays on survival is unknown. Using a prospectively maintained bariatric intake database, we identified consecutive applicants who were evaluated and medically cleared by our multidisciplinary care team and for whom insurance approval was requested. We compared survival in those who were initially approved by their insurance carriers (controls) and those who were initially denied coverage (subjects). Mortality was determined using the Social Security Death Index. Kaplan-Meier survival curves were plotted and the log-rank test for significance was applied. From August 2003 to December 2008, 463 patients (391 females, mean age 45 ± 10 years, mean body mass index 52.5 ± 9.4 kg/m(2)) were medically cleared for a bariatric procedure. Of these, 363 were approved by insurance on initial request, whereas 100 were denied. Given the study's intention to measure the aggregate impact of delays and denials, nine patients who later came to operation after appeal or coverage change were maintained in the subject cohort. During 0- to 113-month follow-up, six subjects (6%) died compared with seven controls (1.9%), corresponding to a statistically significant survival benefit for patients initially approved for bariatric surgery without delay or denial (P < 0.001). In conclusion, access to bariatric surgical care was impeded by insurance certification processes in 22 per cent of medically acceptable candidates. Processes that delay or restrict efficient access to bariatric surgery are associated with a 3-fold mortality increase.