1223 INTEGRATED ORGAN PRINTER FOR RECONSTRUCTION

Vol. 187, No. 4S, Supplement, Monday, May 21, 2012

1222 FIRST CLINICAL PYELOPLASTY SERIES EMPLOYING THE NOVEL DA VINCI SINGLE SITE ROBOTIC PLATFORM FOR THE SURGICAL TREATMENT OF URETERO-PELVIC JUNCTION OBSTRUCTION: FEASIBILITY AND PRELIMINARY RESULTS Andrea Cestari*, Nicolo` Buffi, Giovanni Lughezzani, Alessandro Larcher, Giuliana Lista, Massimo Lazzeri, Patrizio Rigatti, Giorgio Guazzoni, Milan, Italy INTRODUCTION AND OBJECTIVES: The aim of this study was to test the technical feasibility and perioperative outcomes of the new robotic Single Site® platform (RSS) for the treatment of upper uretero-pelvic junction obstruction (UPJO) in a selected group of patients. METHODS: Between July 2011 and September 2011, 7 patients (4 males and 3 females) underwent robotic SSP using the novel DaVinci Single Site® platform for symptomatic UPJ obstruction at our Department of Urology. Patients were preoperatively evaluated with CT scan and renal scan. Mean patient age was 32.8 years (range: 19-55) and mean patient body mass index was 22.7 (range 19 to 26). The site of UPJO was right in 6 cases and left in 1 case. RESULTS: All the procedures were completed without need for traditional robotic surgery or laparoscopic/open conversion. In one patient with congenital hepatomegaly it was necessary to employ an auxillary 3 mm trocar to properly retract the liver and expose the surgical field. Mean operative time was 169 minutes (range 150-185). No intraoperative complications were recorded and blood loss was negligible. Indwelling catheter was removed on clinical basis on postoperative day 2 in 4 patients and on postoperative day 3 in 3 patients. Patients were discharged the following day, after drain removal. One patient experienced tranxient hyperpyrexia that was treated with antibiotics. No other complications were observed. All patients removed the DJ stent 4 weeks after surgery, following negative urine culture and abdominal ultrasound evaluation. CONCLUSIONS: RSS pyeloplasty appears to be a technically feasible and reproducible surgical procedure for the minimally invasive treatment of UPJO. Prolonged follow-up and larger series are required to confirm its potential role as a valid alternative to standard robotic pyeloplasty. Source of Funding: None

1223 INTEGRATED ORGAN PRINTER FOR RECONSTRUCTION Hyun-Wook Kang*, Sang Jin Lee, Anthony Atala, James Yoo, Winston Salem, NC INTRODUCTION AND OBJECTIVES: Organ printing using inkjet technology is evolving into a viable method to fabricate tissue constructs. However, the current bioprinting technology utilizes hydrogels, which present with limitations in maintaining structural integrity due to their low mechanical strength. This makes handling and surgical suturing difficult. We developed a novel organ printing system that integrates solid freeform fabrication and cell printing technology. We investigated the feasibility of delivering viable cells while fabricating durable synthetic scaffolds simultaneously to create durable tissue structures. METHODS: The integrated organ printer consists of four delivery systems that can process multiple types of materials, including synthetic polymers and a cell/gel mixture. The materials are precisely dispensed by the control of air pressure and a heating unit for dispensing synthetic polymers. A mixture of hyaluronic acid (3 mg/ml), fibrinogen (10 mg/ml) and gelatin (10 mg/ml) was used to deliver fibroblasts. Polycaprolactone (PCL) was used for the construction of a highstrength structure. Fibroblasts were carefully mixed with the prepared materials at a concentration of 106 cells/ml and delivered at 20 kPa pressure through a nozzle (120 ␮m). The resulting construct was crosslinked by dipping it into a 20 U/ml thrombin solution for 30 min. Cell viability was evaluated using the live/dead staining.

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RESULTS: The printed cells were confirmed within the synthetic polymers using an inverted microscope. Cells appeared morphologically normal and showed evidence of proliferation 1 day after printing. The printed cells were viable on day 0 and day 3 as evidenced by the viability assay. The percentage of live cells increased as time progressed. The constructed 3-D structures contained viable cells that were pre-labeled with fluorescent dye. Two different cell types were confirmed within a single printed structure with the use of 2 different dye (red and green). CONCLUSIONS: We have successfully designed and constructed an integrated organ printing system that is able to print a 3-D organ structures with precision. This system is able to process cells, gel biomaterials and synthetic polymers simultaneously to yield a durable structure. This system provides a major leap in the advancement of organ printing technology. Source of Funding: This study was supported, in part, by Department of Defense

1224 COST COMPARATIVE ANALYSIS OF CONVENTIONAL LAPAROSCOPIC VERSUS ROBOTIC-ASSISTED NEPHRECTOMY AND PARTIAL NEPHRECTOMY IN CHILDREN Micahel Pierce*, Alan Retik, Hiep Nguyen, Boston, MA INTRODUCTION AND OBJECTIVES: As costs continue to grow in healthcare despite a struggling economy, high-cost technologies like the da Vinci® surgical robot have come under understandable scrutiny. However, while the cost of the machine is substantial, amortized over its useful lifetime, this represents only a fraction of the overall cost of a surgery. Additionally, the robot may expand the capabilities of surgeons and improve patient outcomes. In this analysis, we undertake a cost comparison in order to assess how well suited the technology is for a specific set of procedures. METHODS: We performed a retrospective, observational, matched cohort study of 108 pediatric patients undergoing either conventional laparoscopic nephrectomy and partial nephrectomy or the equivalent robot-assisted procedure from January 2000 to December 2010 at a single institution. Patients were matched based on surgery type and age. Internal costs from the institution were used to compare the two surgical approaches across several procedures. RESULTS: Robotic-assisted surgery direct costs were significantly higher than conventional laparoscopic surgery. This cost difference was primarily due to the difference in surgical equipment costs. Operative time was also significantly longer for patients undergoing robotic surgery (5.25 vs. 4.28 hours, p ⫽ 0.003) substantially increasing cost. Hospital length of stay and time in the post anesthesia care unit, however, were not significantly different. When estimates of the indirect costs of robot purchase and maintenance were included, laparoscopic surgery was an additional two thousand five hundred dollars more expensive. There were no differences in follow-up times or complication rates. CONCLUSIONS: Robotic-assisted laparoscopic surgery was more expensive than conventional laparoscopic surgery for both simple and partial nephrectomy in children. This, combined with longer operative times and no difference in length of stay or complication rates indicates that the da Vinci® surgical robot may be ill-suited to these procedures. Operative time for robotic surgery did improve over time with a dedicated team, actually surpassing that of conventional laparoscopic surgery in the final year of the study, but costs remained substantially higher. Robotic-assisted laparoscopic surgery has many advantages, but it may be best applied to more challenging surgeries without a viable laparoscopic alternative. Source of Funding: None