Faculty Bibliography

OBJECTIVE:: To conduct a systematic review to identify surgical strategies that may decrease leak after laparoscopic sleeve gastrectomy (LSG). BACKGROUND:: LSG is growing in popularity as a primary bariatric procedure. Technical aspects of LSG including bougie size remain controversial. METHODS:: Our systematic review yielded 112 studies encompassing 9991 LSG patients. A general estimating equation (GEE) model was used to calculate the odds ratio (OR) for leak based on bougie size, distance from the pylorus, and use of buttressing on the staple line. Baseline characteristics, including age and body mass index (BMI), were included. A linear repeated measures regression model compared excess weight loss (%EWL) between bougie sizes. RESULTS:: A total of 198 leaks in 8922 patients (2.2%) were identified. The GEE model revealed that the risk of leak decreased with bougie >/=40 Fr (OR = 0.53, 95% CI = [0.37-0.77]; P = 0.0009). Buttressing did not impact leak. There was no difference in %EWL between bougie <40 Fr and bougie >/=40 Fr up to 36 months (mean: 70.1% EWL; P = 0.273). Distance from the pylorus did not affect leak or %EWL. CONCLUSIONS:: Utilizing bougie >/=40 Fr may decrease leak without impacting %EWL up to 3 years. Distance from the pylorus does not impact leak or weight loss. Buttressing does not seem to impact leak; however, if surgeons desire to buttress, bioabsorbable material is the most common type used. Longer-term studies are needed to definitively determine the effect of bougie size on weight loss after LSG.

BACKGROUND: Previous studies have shown accelerated gastric emptying after sleeve gastrectomy. This study aimed to determine whether a correlation exists between immediate postoperative gastroduodenal transit time and weight loss after laparoscopic sleeve gastrectomy (LSG). Specifically, correlation tests were conducted to determine whether more rapid transit after LSG correlated with increased weight loss. METHODS: Data were collected from an institutional review board-approved electronic registry. All LSGs were performed over a 40-Fr bougie, starting 5 to 7 cm proximal to the pylorus. Gastroduodenal transit time (antrum to duodenum) was calculated from a postoperative day 1 esophagram. Pearson's correlation coefficient was used for statistical analysis. RESULTS: The analysis included 62 consecutive LSG patients. The mean gastroduodenal transit time was 12.3 +/- 19.8 s. Almost all the patients (99 %) had a transit time less than 60 s. The mean percentage of excess weight loss (%EWL) was 23.8 +/- 9.8 % at 3 months, 37.9 +/- 11.8 % at 6 months, and 52.2 +/- 10.8 % at 12 months. No correlation was found between gastroduodenal transit time and %EWL at 3, 6, or 12 months. CONCLUSION: No correlation was found between gastroduodenal transit time and weight loss after LSG.

BACKGROUND: Surgical correction of hiatal hernia (HH) during bariatric surgery has been found to improve patient outcomes and decrease reoperation rate. Although barium esophagram is more sensitive than endoscopy for detection of HH, accurate preoperative diagnosis remains a challenge. The aim of this study is to determine whether diagnostic accuracy improves by utilizing right anterior oblique (RAO) esophagram technique instead of the commonly used upright technique when comparing to the gold standard of intraoperative detection. METHODS: All patients undergoing bariatric surgery were prospectively evaluated for HH by barium esophagram. After the first 69 patients, the technique was changed from upright to RAO. Hiatal hernia was assessed intraoperatively by laxity of the phrenoesophageal ligament and, if present, was repaired posteriorly. Two board-certified radiologists specializing in gastrointestinal radiology, who were blinded to the intraoperative results, retrospectively reviewed the esophagrams. Consensus reads were utilized for divergent opinions. Sensitivity and specificity were calculated for each technique. RESULTS: Between 2008 and 2010, a total of 388 patients underwent preoperative esophagrams (69 upright, 388 RAO). For upright esophagram, sensitivity was 50 % and specificity was 97 %. For RAO esophagram, sensitivity was 70 % and specificity was 77 %. RAO had a lower percentage of false negatives (11 vs. 21 %) than upright esophagram. CONCLUSIONS: The use of RAO technique for preoperative esophagram is more sensitive for diagnosis of hiatal hernia than upright esophagram. If surgeons desire routine preoperative esophagram, RAO technique is the best.

BACKGROUND: Obesity is frequently associated with respiratory symptoms despite normal large airway function as assessed by spirometry. However, reduced functional residual capacity and expiratory reserve volume are common and might reflect distal airway dysfunction. Impulse oscillometry (IOS) might identify distal airway abnormalities not detected using routine spirometry screening. Our objective was to test the hypothesis that excess body weight will result in distal airway dysfunction detected by IOS that reverses after bariatric surgery. The setting was a university hospital. METHODS: A total of 342 subjects underwent spirometry, plethysmography, and IOS before bariatric surgery. Of these patients, 75 repeated the testing after the loss of 20% of the total body weight. The data from 47 subjects with normal baseline spirometry and complete pre- and postoperative data were analyzed. RESULTS: IOS detected preoperative distal airway dysfunction despite normal spirometry findings by an abnormal airway resistance at an oscillation frequency of 20 Hz (4.75 +/- 1.2 cm H(2)O/L/s), frequency dependence of resistance from 5 to 20 Hz (2.20 +/- 1.6 cm H(2)O/L/s), and reactance at 5 Hz (-3.47 +/- 2.1 cm H(2)O/L/s). Postoperatively, the subjects demonstrated 57% +/- 15% excess weight loss. The body mass index decreased (from 44 +/- 6 to 32 +/- 5 kg/m(2), P < .001). Improvements in functional residual capacity (from 59% +/- 11% to 75% +/- 20% predicted, P < .001) and expiratory reserve volume (from 41% +/- 20% to 75% +/- 20% predicted, P < .001) were demonstrated. Distal airway function also improved: airway resistance at an oscillation frequency of 20 Hz (3.91 +/- .9, P < .001), frequency dependence of resistance from 5 to 20 Hz (1.17 +/- .9, P < .001), and reactance at 5 Hz (-1.85 +/- .9, P < .001). CONCLUSION: The present study detected significant distal airway dysfunction despite normal preoperative spirometry findings. The effect of increased body weight was likely the main mechanism for these abnormalities. However, the inflammatory state of obesity or associated respiratory disease could also be invoked. These abnormalities improved significantly toward normal after weight loss. The results of the present study highlight the importance of bariatric surgery as an effective intervention in reversing these respiratory abnormalities.

BACKGROUND: Many insurance payors mandate that bariatric surgery candidates undergo a medically supervised weight management (MSWM) program as a prerequisite for surgery. However, there is little evidence to support this requirement. We evaluated in a randomized controlled trial the hypothesis that participation in a MSWM program does not predict outcomes after laparoscopic adjustable gastric banding (LAGB) in a publicly insured population. METHODS: This pilot randomized trial was conducted in a large academic urban public hospital. Patients who met NIH consensus criteria for bariatric surgery and whose insurance did not require a mandatory 6-month MSWM program were randomized to a MSWM program with monthly visits over 6 months (individual or group) or usual care for 6 months and then followed for bariatric surgery outcomes postoperatively. Demographics, weight, and patient behavior scores, including patient adherence, eating behavior, patient activation, and physical activity, were collected at baseline and at 6 months (immediately preoperatively and postoperatively). RESULTS: A total of 55 patients were enrolled in the study with complete follow-up on 23 patients. Participants randomized to a MSWM program attended an average of 2 sessions preoperatively. The majority of participants were female and non-Caucasian, mean age was 46 years, average income was less than $20,000/year, and most had Medicaid as their primary insurer, consistent with the demographics of the hospital's bariatric surgery program. Data analysis included both intention-to-treat and completers' analyses. No significant differences in weight loss and most patient behaviors were found between the two groups postoperatively, suggesting that participation in a MSWM program did not improve weight loss outcomes for LAGB. Participation in a MSWM program did appear to have a positive effect on physical activity postoperatively. CONCLUSION: MSWM does not appear to confer additional benefit as compared to the standard preoperative bariatric surgery protocol in terms of weight loss and most behavioral outcomes after LAGB in our patient population.

Introduction: Airway dysfunction has been detected by oscillometry in obese subjects despite normal large airway function as assessed by spirometry. This has been attributed to lung/airway compression as reflected by reduced FRC; we previously demonstrated improvement of abnormalities towards normal upon voluntary inflation to predicted FRC (AJRCCM 2010; 181:A2532). However, other causes of airway dysfunction such as inflammation or concomitant intrinsic airway disease may coexist and could not be excluded. The present study re-evaluated these subjects following bariatric surgery induced weight loss to evaluate for residual abnormality. Methods: 22 morbidly obese subjects without history of smoking and/or cardiopulmonary disease, underwent evaluation pre/post bariatric surgery (20% reduction in weight). Spirometry, plethysmography and impulse oscillometry (IOS) were performed. IOS parameters included resistance at 5Hz (R5), resistance at 20Hz (R20) frequency dependence of resistance (R5-20) and reactance at 5Hz (X5).IOS was also performed at an elevated lung volume (~1 liter) targeted to restore FRC to predicted values. All IOS measurements were repeated post bronchodilator. Results: Baseline weight and BMI were 256+/-43 kg and 46+/-7 kg/m², respectively. All subjects lost >20% of body weight, but obesity persisted in all subjects (weight 182 kg, BMI 33 kg/ m2). FEV /FVC was normal at baseline and remained unchanged post weight loss 1 (81+/-3% vs 83+/-4%) indicating normal large airway function. FRC and ERV improved post weight loss but values remained abnormal (FRC from 60+/-12 to 77+/-21% predicted, ERV from 46+/-16 to 75+/-38% predicted, p<0.05). Although IOS parameters improved following weight loss, data remained above the upper limit of normal (R5 from 6.8+/-1.8 to 5.1+/-1.4 cmH₂O/l/s, R₂₀ from 4.7+/-1.1 to 3.9+/-0.9 cmH₂O/l/s, R_5-20 from 2.1+/-1.1 to 1.2+/-0.9 cmH_2O /l/s, X₅ from -3.2+/-1.7 to -1.8+/-0.9 cmH₂O /l/s, p<0.05). Since FRC remained abnormal following weight loss, IOS was repeated following voluntary lung inflation (FRC 142+/-30%). While R20 corrected to normal at the elevated FRC (R₂₀ 3.1+/-1.0 cmH₂ O/l/s), R5, R5-20 and X5 remained abnormal indicating residual distal airway dysfunction (R₅ 4.2+/-1.4 cmH₂O/l/s, , R_5-20 1.1+/-0.7 cmH₂O /l/s, X₅ -2.0+/-0.8 cmH₂O /l/s); these residual oscillometric abnormalities were present in 11/22 subjects. Residual airway dysfunction was demonstrated by low specific conductance (assessed at 5HZ) despite restoration of FRC to supranormal values. Conclusions: Distal airway dysfunction persisted following weight loss and was not attributable to persistent mass loading in a subgroup of patients without clinical evidence of airway disease. These abnormalities may represent either functional abnormalities due to persistent obesity and/or intrinsic airway disease

BACKGROUND: Weight regain after Roux-en-Y gastric bypass (RYGB) is increasingly reported in the bariatric literature. Laparoscopic sleeve reduction of the gastrojejunal complex is a surgical option to revise a dilated gastric pouch. We report our short-term results. METHODS: Sleeve reduction entails serial firing of a linear stapler along the jejunal alimentary limb, across the gastric pouch and towards the left crus, with a bougie in place, thus, creating a new 20-25-cm reduced gastrojejunal complex. Data analyzed included age, body mass index (BMI), excess weight loss (EWL), comorbidity resolution, and any other simultaneous operative procedures. RESULTS: Fourteen patients were identified, all done laparoscopically. Nine underwent gastrojejunal sleeve reduction alone and five underwent additional lengthening of the Roux limb. There were no mortalities. Mean age at revision was 43 years (31-59). Mean BMI and EWL prior to revision were 35.5 +/- 4.0 kg/m(2) and 48.9 +/- 15.8%, respectively. Nine of 14 patients (64%) had obesity-related comorbidities prior to the revision. Average BMI decrease was 2.7 kg/m(2). Post-revision mean BMI and %EWL were 32.9 +/- 4.7 kg/m(2) and 12.0 +/- 13.9%, respectively, with mean follow-up of 12 months. Three of nine patients (33%) experienced improvement and/or resolution of comorbidities. We did not find a significant difference between pre-and post-revision mean BMI and %EWL (p = 0.13) even after separately evaluating those patients who underwent Roux limb lengthening (p = 0.16). CONCLUSION: For RYGB patients who regained weight, laparoscopic gastrojejunal sleeve reduction does not seem to offer a major therapeutic benefit. Additional malabsorptive Roux lengthening also does not provide a significant benefit. Other options should be considered, such as placing a band on the gastric pouch or conversion to duodenal switch.

Introduction: Participation in a medically-supervised weight management (MSWM) program before bariatric surgery is mandated by several insurance payers. However, this requirement is not evidencebased and serves as a barrier to medically necessary treatment. We conducted a pilot randomized trial funded by SAGES to determine the effect of an insurance-mandated MSWM prior to surgery. Our hypotheses are: (1) There is no difference in BMI between patients who have participated in a medically-supervised weight management program and those who don't. (2) MSWM does not change self-reported adherence, physical activity, eating behavior, and health beliefs. Methods & Procedures: 55 patients were scheduled for laparoscopic adjustable gastric banding (LAGB) and consented to enroll in an ongoing prospective pilot study in a large public hospital. of these, 12 patients cancelled surgery and 10 patients have been enrolled for less than 6 months. Thus, 33 patients were included in the analysis, with 17 randomized to MSWM (defined as monthly visits over 6 months directed by a physician or nutritionist) and 16 randomized to usual care. Measures of weight, height, adherence, activity level, health beliefs, and eating behavior were obtained at enrollment (ie, baseline) and 6 months after enrollment (ie, MSWM program completion and 2 weeks prior to surgery). For categorical and continuous data, Fisher's Exact Test and t-test were used to compare groups at the 2 time points before surgery. Results: Mean age was 45.5 (SD = 12.5) years. Majority were female (97%) and non-Caucasian (85%) with an income of less than $20,000 (64%). No significant differences were found between MSWM and usual care for age, gender, ethnicity, education, and income, indicating that the 2 groups were evenly matched for demographic variables. Mean BMI for the MSWM group was 46.3 kg/m2 at baseline and 46.0 kg/m2 at 6 months. Mean BMI for usual care was 44.7 kg/m2 and 44.6 kg/m2 (see Table 1). After 6 months of eitherMSWMor wait and at pre-surgery, no significant differences in BMIor patient behaviors were found between the 2 groups. Preliminary analysis of available 3-month post-operative data (n = 13) showed similar mean BMI when comparing MSWM (41.3 kg/m2) and usual care (41.2 kg/m 2). Conclusion: Our preliminary results indicate that MSWM does not affect BMI changes or patient behaviors prior to or after LAGB surgery

Background: Hiatal hernia repair at the time of bariatric surgery improves patient outcome, decreases GERD symptoms and reduces the need for reoperation. The aim of this report is twofold: first, to compare the sensitivity of esophagram with surgical findings at the time of bariatric surgery, and second, to compare the sensitivities of upright versus right anterior oblique (RAO) recumbent esophagram in predicting the presence of hiatal hernia intraoperatively. Methods: Between 2008 and 2010, 389 patients undergoing bariatric surgery were prospectively evaluated for hiatal hernia by barium esophagram. 70 (18%) were performed only in the upright position and 319 (82%) only in the RAO recumbent position. Esophagram technique was changed from upright to recumbent because we hypothesized that we would be able to better detect hiatal hernia utilizing RAO recumbent technique. Hiatal hernia was assessed intraoperatively by laxity/dimpling of the phrenoesophageal ligament and, when present, was repaired posteriorly with permanent sutures. Results: Compared with the surgical findings, the sensitivity and specificity for upright esophagram was 50% and 97%, respectively. For recumbent esophagram, sensitivity was 70% and specificity was 77%. Recumbent esophagram had a lower percentage of false negatives than upright esophagram (11% vs. 21%). Conclusions: Use of a recumbent technique for preoperative esophagram has a higher sensitivity for diagnosis of hiatal hernia than upright esophagram. Routine use of recumbent esophagram results in increased preoperative detection of hiatal hernia and facilitates planning of crural closure