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day on liquid diet. Two patients reported transient heartburn, which was well controlledwith medications. The average pre-op GERD-HRQL was 20, which improved to 11.3 at 7days post-op and 2 at 30 days post-op. To date, two patients have already returned for their6-month follow-up, reporting adequate swallowing and low LES pressures on esophagealmanometry (their mean pre-op LES resting pressure was 33 mmHg and residual pressurewas 41.35 mmHg, whereas the 6-months follow-up mean LES resting pressure was 10.85mmHg and residual pressure was -0.8 mmHg). Conclusion: TEEM seems to be safe, feasibleand effective for the treatment of patients with achalasia. Long-term data is still necessaryfor wide-spread utilization of this novel technique.

803

Single Incision Laparoscopic Heller Myotomy and Dor FundoplicationJohn Afthinos, Koji Park, James McGinty, Ninan Koshy, Julio Teixeira

Introduction: We describe our technique for single incision laparoscopic (SILS) Hellermyotomy. The minimally invasive nature of a SILS approach may appeal to patients con-sidering conservative, non-surgical therapy for achalasia, like endoscopic dilatation or botuli-num toxin injection. Technique: A Heller myotomy and partial anterior fundoplication areperformed through an umbilical SILS port. A penrose drain facilitates retraction. Intraoper-ative endoscopy confirms adequacy of the myotomy. Conclusion: Heller myotomy and Dorfundoplication is technically feasible through a SILS approach, and offers a competitive,minimally invasive alternative to non-operative treatment options.

804

Bariatric Surgery Outcomes in the Elderly Population: An ACS NSQIP StudyRobert B. Dorman, Anasooya Abraham, Waddah B. Al-Refaie, Helen M. Parsons, SayeedIkramuddin, Elizabeth Habermann

Introduction: Bariatric surgery has been shown to be beneficial in achieving weight loss andin decreasing long-term mortality. To date, however, evidence has suggested an increasedmortality following bariatric surgery in patients≥ 65 years. With adjustment of confoundingvariables, we hypothesized that the short-term operative outcome profile in those ≥ 65years undergoing bariatric surgery would be comparable to that of younger persons. Methods:Patients with BMI ≥ 35 kg/m2 who underwent open and laparoscopic Roux-en-Y gastricbypass, open duodenal switch, laparoscopic adjustable gastric banding and vertical bandedgastroplasty in the 2005 - 2009 American College of Surgeons National Surgical QualityImprovement Program were identified. Controlling for confounders and stratifying by openversus laparoscopic surgery, multivariate regression was used to predict the impact of age(≥ 65 years) on mortality, major events and prolonged length of stay (PLOS, > 90thpercentile) at 30 days. Results: We identified 48,378 patients who underwent the abovebariatric procedures between 2005 and 2009. Over the previous 5 years, the percentage ofolder patients undergoing bariatric surgery has increased from 1.92% in 2005 to 4.77% in2009 (p < 0.001). There were only 72 deaths throughout the entire study period, 8 of whichwere in the ≥ 65 years cohort. The incidence of 30-day mortality in those 35-49, 50-64and ≥ 65 years was 0.12%, 0.21% and 0.40%, respectively. Adjusting for confounders,multivariate regression analysis demonstrated advancing age to trend towards becoming apredictor of mortality but it was not significant (Table 1). Age ≥ 65 was a significantpredictor of PLOS for both open and laparoscopic procedures. For those who underwentlaparoscopic procedures, odds ratios were similar for PLOS for the 50-64 years and ≥ 65years' cohorts. While major adverse events were not predicted by age ≥ 65 for either openor laparoscopic procedures, BMI ≥ 55 kg/m2, severe ASA score, cardiac co-morbidities,albumin < 3 and creatinine > 1.5 were all predictors of major adverse events (not shown).Conclusions: This large, multi-hospital study demonstrates older age predicts short-termPLOS but not major events. The overall low death rates likely explain the observed trendtoward significance in operative mortality in older patients. Thus surgeons should continueto promote caution when considering whether to operate on this patient population. Oncecorroborated, these results provide important information to patients, surgeons, hospitals,and payers prior to performing bariatric surgery in older persons with obesity.Table 1. Predictors of 30-day Mortality and Prolonged Length of Stay

Multivariate regression analysis, controlling for confounders, was used to formulate theabove odds ratios. Confounders adjusted for include, but are not limited to, age, BMI, sex,race, ASA score, diabetes, pulmonary and cardiac comorbidities, albumin, creatinine, andadmission year.

S-1002SSAT Abstracts

805

Counter-Clockwise Rotation of Roux-en-Y Limb Significantly Reduces InternalHerniation in Laparoscopic Roux-en-Y Gastric Bypass (LRYGB)Kalyana Nandipati, Edward Lin, Farah A. Husain, Jahnavi Srinivasan, John F. Sweeney, S.S. Davis

Introduction: Internal hernias continue to be a significant source of morbidity after LRYGB.Literature addressing the technique of Roux limb construction as a predisposing factor issparse. The objective of this study is to evaluate the impact of Roux limb constructiontechnique on the development of internal hernias. Methods: In this study we included 444consecutive patients (367 (82.7%) females and 77 (17.3%) males) from bariatric databasewho underwent LRYGB at our Institution. Variables collected include demographics, bodymass index (BMI) before and after the procedure, and postoperative small bowel obstructionsecondary to internal herniation. Technical details collected include; type of roux-en-y limbconstruction, Peterson's defect closure at initial operation and reoperative findings. Rouxlimbs were constructed in 291 patients by a clockwise rotation of the bowel and jejuno-jejunostomy performed on the right side of the axis of the mesentery (Group 1). In 153patients the Roux limb was constructed by a counterclockwise rotation of the Roux limbresulting in the jejuno-jejunostomy on the left side of the axis of the mesentery (Group 2).We also analyzed the impact of Peterson's space closure on internal hernias. Fisher's exacttest and Chi-square test used for the analysis. Results: Of a total 444 [mean age - 43.7 +10.3 years, mean BMI pre op was 46.4 + 5.1, BMI after median follow up of 12 monthswas 34.5 + 6.98] patients included in the study, 21 (4.7%) internal hernias were identified.Of 21 internal hernias, 17 (81%) were through Peterson's space and 4 (19%) were throughmesenteric defect. Group 1 patients had significantly higher overall internal hernias (20/291, 6.9% vs 1/153, 0.7%; P = 0.0018) and Peterson's hernias (16/275, 5.8% vs 1/152,0.6%; P = 0.0089) compared to Group 2. In addition, no significant difference was notedin the incidence of Peterson's hernia whether the defect was closed or not closed (closedgroup - 4/117, 3.4% vs. not closed - 13/327, 4%; P = 1.00). Within Peterson's defect closedgroup, clockwise rotation and anastomosis to the right side of axis of mesentery was associatedwith significantly higher incidence of Peterson's hernias compared to counter clockwiserotation (4/54 vs 0/63, P = 0.043). In not closed group, clockwise rotation was associatedwith higher incidence of internal hernias that did not reach statistical significance (12/237,5.1% vs 1/90, 1.1%; P = 0.12). Summary: This study demonstrates that the technique forconstruction of the Roux limb probably is a major factor in the development of internalhernias. Construction of the Roux limb with a counter-clockwise rotation of the bowel, suchthat both jejuno-jejunostomy anastomosis and Ligament of Treitz are to the left of the axisof the mesentery significantly reduces the incidence of internal hernias.

806

Factors Predictive of Recurrence and Mortality After Definitive Surgical Repairof Enterocutaneous FistulaJose L. Martinez, Enrique Luque-de-León

Background: Most enterocutaneous fistulae (ECF) require operative treatment. Althoughrecent advances have widened therapeutic options, recurrence after surgical repair has notchanged substantially. Assessment of outcomes specifically regarding recurrence and mortal-ity after surgical repair has not been studied extensively. Aim: To determine factors associatedwith recurrence and mortality in patients submitted to surgical repair of ECF. Material andMethods:We analyzed prospectively collected databases on all consecutive patients submittedto surgical repair of ECF during a 5 year period. Several patient, disease and operativevariables were assessed as factors related to recurrence and mortality. Univariate statistical(UA) comparisons were made using Students T Test for continuous variables and Fischersexact test for categorical variables. Multivariate analyses (MA) were also performed. Results:A total of 71 patients were included. Median age was 52 y. (range, 17-81). Operativeindications included ECF persistence (38), sepsis (17), eversion of mucosa (12), and others(4). Surgical treatment included resection and anastomosis (37), resection and ostomy (21),oversew (4), bypass (3), and catheter placement (2). ECF recurred in 22 patients (31%).Medical treatment was established in 9 (with ECF closure in 7); surgical repair was re-attempted in 13 others (attained in 11). Thus, management of 22 patients with recurrentECF was successful in 18 (82%). UA disclosed non-colonic ECF origin (p=0.04) and highoutput (p=0.001) as risk factors for recurrence. This latter was the only one that prevailedafter MA (p=0.01). Although not statistically significant, management with an open abdomen(p=0.06) and enteroatmosferic fistulae (p=0.07) had a tendency to favor recurrence. A totalof 14 patients died (20%). UA revealed several risk factors for mortality measured at diagnosisor referral including malnutrition (p=0.03), sepsis (p=0.01), hydroelectrolytic imbalance (p=0.001), and serum albumin < 3 g/dl (p=0.02). Other significant variables were interval fromdiagnosis to operation ≤ 20 weeks (p=0.03), preop. serum albumin < 3 g/dl (p=0.001),and age ≥ 55 years (p=0.03). Only the latter two remained significant after MA. A slighttendency was observed for female gender (p=0.07) and non-colonic ECF origin (p=0.09).Interestingly recurrence after surgical treatment was not associated with mortality (p=0.75).Conclusions: Among several studied variables, recurrence was only independently associatedwith high output. Interestingly, once ECF recurred its management was as successful asnon-recurrent fistulas in our series (closure rate of 82%). Mortality was associated to previ-ously reported bad prognostic factors at diagnosis or referral. Timing of operation (> 20weeks) seems relevant in order to optimize patients functional and nutritional status.

807

Assessment of In Vivo Functionality of a Novel Cancer-Targeting AdenovirusExpressing Interferon Alpha in an Immunocompetent ModelLeonard Armstrong, Julia Davydova, Eric J. Brown, Selwyn M. Vickers, Masato Yamamoto

More effective systemic therapy is clearly needed for pancreatic adenocarcinoma. Interferonalpha (IFNα) is promising in multimodality therapy, but has a short half-life and strongside effects. We hypothesize that by expressing IFNα locally in the tumor environmentusing a replicating tumor-specific adenovirus, systemic side effects can be greatly minimized