44. PERFORMANCE ON A CADAVERIC PORCINE LAPAROSCOPIC JEJUNO-JEJUNOSTOMY MODEL ENABLES ACCURATE EVALUATION OF TECHNICAL SKILLS IN THE OPERATING ROOM. Camilo Boza, MD 1 , Rajesh Aggarwal, MD 2 , Alex Escalona, MD 1 , Philip Bellilio, MD 1 , Nicolas Devaud 1 , Ara Darzi, MD 2 , Luis Ibanez, MD 1 , 1 Pontificia Universidad Catolica, Santiago, Chile, 2 Imperial College London, London, UK. Background: Laparoscopic Roux-en-Y gastric bypass (LRYGBP) is an effective surgical therapy for morbid obesity, but has a long and arduous learning curve. Fellowships aim to reduce the learning curve through preceptorship-based practice. However, many sur- geons commence training on anaesthetized porcine model which is expensive and requires specialist facilities. The aim of this study was to develop and assess the use of a cadaveric porcine model for assessment of skills acquisition in LRYGBP. Methods: Porcine small bowel was filled with thickened solution, divided into 50cm lengths, and placed into a video-box trainer in a U-shape. This provided the illusion of two adjacent pieces of small bowel. Eight surgeons with varying laparoscopic bariatric surgical experience (median 38 LRYGBPs, range 0-340) per- formed a side-to-side stapled jejuno-jejunostomy on the model, and also on patients scheduled for LRYGBP. Assessment was by time taken, dexterity parameters (path length and number of move- ments) and scored by two reviewers on a video-based rating scale. Results: There were significant correlations between performance on the porcine model and patient for dexterity measures, i.e. left hand path length (r=0.86, p=0.007), right hand path length (r=0.81, p=0.02) and total number of movements (r=0.74, p=0.04), though not for time taken (r=0.67, p=0.07). There was also a significant correlation on video-based rating scores (r=0.80, p0.001). Conclusion: This model is an accurate representation of a jejuno- jeunostomy in the human procedure. It is inexpensive, easy to- ‘make, and does not require any special storage or handling facil- ities. This study also stresses the importance of dexterity as key factors for assessment of laparoscopic skill. PII: S1550-7289(06)00314-5 45. A COMPARISON OF THE EFFECTS OF GASTRIC BYPASS (GBP) AND THE BILIOPANCREATIC DIVERSION WITHE THE DUODENAL SWITCH (BPD/ DS) ON BODY COMPOSITION 1 TO 2 YEARS AFTER SURGERY. Gladys Wit Strain, PhD 1 , Michel Gagner, MD 1 , Alfons Pomp, MD 1 , William B. Inabnet, MD 22 Weill/Cornell, New York, NY, 2 Columbia, New York, NY. Background: GBP is the most common surgery for weight loss in the United States. The BPD/DS is less routinely performed, per- haps because of its technical difficulty and metabolic concerns. The objective of this study was to determine if these procedures had differential effects on weight loss and body composition. Methods: Body composition was measured by bioimpedance methodology (Tanita 310 validated for morbid obesity) at initial consultation, and follow-up measurements were completed one to two years after surgery. Results: Thus far 47 patients with GBP and 18 with BPD/DS have follow-up measurements. Prior to surgery the Body Mass Indexes (BMI) were not different, pre-GB 48.5 6.3 and pre-BPD/DS 52.2 10.8 (p=0.08). Percentage body fat also did not differ: GBP 48.9 8.2 % and BPD/DS 47.9 5.1% (p= 0.65). After surgery GBP BMI was 32.7 5.8, BPD/DS 29.9 6.1 (p= 0.09). GBP patients % body fat changed from 48.9 8.2 % to 33.411.0% and BPD/DS decreased from 47.9 5.1% to 24.810.6% (p=0.006). Further analysis revealed BMI had decreased 15.8 5.3 units after GBP and 21.96.0 units after BPD/DS (p= 0.0002). The change in fat was 15.6 9.1% after GBP and 22.3 7.8% after BPD/DS (p= 0.008). Conclusion: The BPD/DS was more effective in reducing the BMI and promoting fat loss than the GBP. The assessment of the impact of these two surgeries on an individualized basis offers additional information. Longitudinal measurements of physiologic variables is essential for meaningful patient evaluations of bariatric proce- dures. PII: S1550-7289(06)00315-7 46. VAGAL BLOCKING FOR OBESITY CONTROL (VBLOC): STUDIES OF PANCREATIC AND GASTRIC FUNCTION AND SAFETY IN A PORCINE MODEL. Katherine S. Tweden, PhD 1 , Michael G. Sarr, MD 2 , Michael Camilleri, MD 2 , Michael L. Kendrick, MD 2 , Frank G. Moody, MD 3 , Michael D. Bierk, DVM 1 , Mark B. Knudson, PhD 1 , Richard R. Wilson, MD 1 , Mehran Anvari, MD, PhD 4 , 1 EnteroMedics Inc, St. Paul, MN, 2 Mayo Clinic College of Medicine, Rochester, MN, 3 University of Texas Health Science Center at Houston, Houston, TX, 4 Mc- Master University, Hamilton, Canada. Background: Algorithms for vagal blockade utilizing intermit- tent, high-frequency electrical current are being evaluated for obe- sity treatment. The physiologic effects targeted are: (1) reducing food consumption and inducing early satiation and prolonged satiety by inhibiting gastric accommodation and contractile activ- ity; and, (2) reducing calorie absorption by inhibiting pancreatic exocrine secretion (PES). Historically, vagotomy for refractory ulcers resulted in short- term loss of appetite and body weight that usually resolved, al- though the mechanism(s) are unclear. Aim: To evaluate the effects of intermittent, high-frequency elec- trical vagal blockade on PES and gastric contractions. Methods: In a chloralose-anesthetized (non-vagolytic) porcine model, electrodes were placed on anterior and posterior vagal trunks at the esophagogastric junction. PES, gastric contractions, heart rate (HR), blood pressure (BP) and blood glucose were measured before, during and after repeated applications of high- frequency algorithms. Vagal nerve morphology and function were evaluated in active (n=5) and control (n=2) animals after eight weeks of electrode implantation. Results: Vagal blockade decreased PES 80% (0.360.10 vs. 0.040.01 ml/h, n=4, p.001). PES returned to baseline values within 5-30 minutes post-blockade. Gastric contractions occurred at a frequency of 4.00.1/min (n=2) during vagal stimulation as 301 Abstracts: Plenary Session 2006 / 2 (2006) 286 –309