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Background Closure of the transgastric access to the peritoneal cavity is a critical step in natural orifice transluminal endoscopic surgery (NOTES). Objective To perform a direct comparison of the histological healing post clips and threaded tags (T-tags) closure after transgastric NOTES procedures. Setting: Design and Intervention Twelve survival porcine experiments. After standardized endoscopic gastric wall puncture, balloon-dilation, and transgastric peritoneoscopy, closure of the gastric wall was performed with either clips or T-tags. Necropsy at 14 days was performed for histological evaluation of 2-mm interval transversal cross sections of the gastrotomy site. Main Outcome Measurements Histological healing of the gastric wall opening. Results Endoscopic closure of the gastrotomy was successfully achieved in all 12 animals, followed by an uneventful 2-week clinical follow-up. Transmural healing was seen in 3 (75%) animals after clip closure compared with only 1 (12.5%) in the group with T-tag closure ( P = .06). Gastric wall muscular bridging was observed in 4 (100%) animals with clip closure compared with only 1 (12.5%) in the group with T-tag closure ( P = .01). Limitations Animal model with short-term follow-up. Conclusions Endoscopic clip closure results in a layer-to-layer transmural healing of the gastric wall. In contrast, T-tag gastric wall plication impairs gastric layer bridging. These findings might guide the future design of new endoscopic devices and techniques for gastrotomy closure after NOTES procedures.

Background and study aims: Minimizing the invasiveness of operations by using natural orifice transluminal endoscopic surgery (NOTES) may reduce adhesion formation. The aim of the study was to compare rates of adhesion formation after peritoneoscopy with liver biopsy by laparotomy, laparoscopy, and transgastric NOTES. Materials and methods: Experimental comparative survival study, at a university hospital. using 18 female pigs weighing 35 - 40 kg. Peritoneoscopy with liver biopsy was randomized to one of three groups: laparotomy, laparoscopy, and transgastric NOTES. Preoperative, operative, and postoperative care was standardized. Main outcome measures were: (i) survival and complication rates; (ii) assessment of adhesion formation using the Hopkins Adhesion Formation Score at necropsy (day 14). Results: 100 % of pigs with laparotomy and 33.3 % with laparoscopy had adhesions compared with 16.7 % who underwent transgastric NOTES. Documented adhesion bands totals for each group were: transgastric NOTES 1; laparoscopy 4; laparotomy 17. Median adhesion formation scores were: laparotomy 2.5 (range 2 - 4), compared with laparoscopy 0.0 (0 - 2), and transgastric NOTES 0.0 (0 - 1) ( P < 0.001). Spearman coefficient analysis revealed that correlation between adhesion scores assigned by two investigators was excellent (r = 0.99, P < 0.001, 95 % confidence interval [CI] 0.9978 - 0.9996). Conclusions: Although this was a short-term study, with a low number of animals, it showed that transgastric NOTES and laparoscopy are associated with statistically significantly lower rates of adhesion formation than open surgery when peritoneoscopy with liver biopsy is performed. Incidence and severity of adhesions were lowest with transgastric NOTES.

Purpose: Although fine-needle aspiration biopsy is the most useful diagnostic tool in evaluating a thyroid nodule, preoperative diagnosis of thyroid nodules is frequently imprecise, with up to 30% of fine-needle aspiration biopsy cytology samples reported as “suspicious” or “indeterminate.” Therefore, other adjuncts, such as molecular-based diagnostic approaches are needed in the preoperative distinction of these lesions. Experimental Design: In an attempt to identify diagnostic markers for the preoperative distinction of these lesions, we chose to study by microarray analysis the eight different thyroid tumor subtypes that can present a diagnostic challenge to the clinician. Results: Our microarray-based analysis of 94 thyroid tumors identified 75 genes that are differentially expressed between benign and malignant tumor subtypes. Of these, 33 were overexpressed and 42 were underexpressed in malignant compared with benign thyroid tumors. Statistical analysis of these genes, using nearest-neighbor classification, showed a 73% sensitivity and 82% specificity in predicting malignancy. Real-time reverse transcription–PCR validation for 12 of these genes was confirmatory. Western blot and immunohistochemical analyses of one of the genes, high mobility group AT-hook 2, further validated the microarray and real-time reverse transcription–PCR data. Conclusions: Our results suggest that these 12 genes could be useful in the development of a panel of markers to differentiate benign from malignant tumors and thus serve as an important first step in solving the clinical problem associated with suspicious thyroid lesions.

Every surgical item used during surgery (e.g., sponges) must be accounted for after surgery to ensure that none of these items is left inside the patient. Despite the numerous precautions in place, in approximately 1 in 1500 cases, something gets left behind inside the patient's body. This paper presents ASSIST, an automated system for surgical instrument and sponge tracking that increases the safety of surgical procedures. ASSIST utilizes RFID (Radio Frequency Identification) technology to aid in accounting for all items used during surgery. The design takes into account safety, simplicity, ease of deployment, and ease of use. An initial evaluation utilizing RFID-tagged sponges demonstrates that ASSIST can reliably track surgical sponges with minimal impact to current operating room procedures. Sources of error that can impact the reliability of the system are also discussed.

“Robotic surgery” originated as an imprecise term, but it has been widely used by both the medical and lay press and is now generally accepted by the medical community. The term refers to surgical technology that places a computer-assisted electromechanical device in the path between the surgeon and the patient. A more scientifically accurate term for current devices would be “remote telepresence manipulators” because available technology does not generally function without the explicit and direct control of a human operator. For the purposes of the document, we define robotic surgery as a surgical procedure or technology that adds a computer technology–enhanced device to the interaction between a surgeon and a patient during a surgical operation and assumes some degree of control heretofore completely reserved for the surgeon. For example, in laparoscopic surgery, the surgeon directly controls and manipulates tissue, albeit at some distance from the patient and through a fulcrum point in the abdominal wall. This differs from the use of current robotic devices, whereby the surgeon sits at a console, typically in the operating room but outside the sterile field, directing and controlling the movements of one or more robotic arms. Although the surgeon still maintains control over the operation, the control is indirect and effected from an increased distance. This definition of robotic surgery encompasses micromanipulators, remotely controlled endoscopes, and console-manipulator devices. The key elements are enhancements of the surgeon’s abilities—be they vision, tissue manipulation, or tissue sensing—and alteration of the traditional direct local contact between surgeon and patient.

Background Ventral hernia repair is currently performed via open surgery or laparoscopic approach. Objective To develop an alternative ventral hernia repair technique. Setting Acute and survival experiments on twelve 50-kg pigs. Design and Interventions An endoscope was introduced transgastrically into the peritoneal cavity. An abdominal wall hernia was created through a 5-mm skin incision followed by a 5-cm-long incision of the abdominal wall muscles and aponeurosis. A hernia repair technique was developed in 3 acute experiments. Then animals were randomized into 2 groups. In the experimental group (5 animals) Gore-Tex mesh was transgastrically attached to the abdominal wall, repairing the previously created abdominal wall hernia. In the control group (4 animals), the hernia was not repaired. In both groups, the endoscope was then withdrawn into the stomach, and the gastric wall incision was closed with T-bars. The animals survived for 2 weeks and were then euthanized. Main Outcome Measurement The presence of ventral hernia on necropsy. Results In the control group, the ventral hernia was present on necropsy in all animals. In the experimental group, the ventral hernia was easily repaired, with no evidence of hernia on necropsy. In the first animal in the experimental group, necropsy revealed infected mesh. After this discovery, we used sterilized cover for mesh delivery and did not find any signs of infection in 4 subsequent study animals. Limitation The study was performed in a porcine model. Conclusions Transgastric ventral hernia repair is feasible, technically easy, and effective. It can become a less invasive alternative to the currently used laparoscopic and surgical ventral hernia repair.

Laparoscopic repair of paraesophageal hernia (PEH) has been shown to result in excellent relief of symptoms and improved quality of life (QOL) despite a relatively high radiographically identified recurrence rate.To assess potential risk factors for recurrence and long-term change in QOL after laparoscopic repair of PEH.This was a prospective study of 111 patients who underwent elective laparoscopic repair of type III PEH with biological mesh buttressed over a primary cruroplasty from April 3, 2009, through July 31, 2014, at the Department of Surgery, Johns Hopkins University of Medicine. We administered a modified version of a validated gastroesophageal reflux disease-specific QOL tool to patients before and at 2, 12, and 36 months after the procedure. Higher QOL scores represent greater severity of symptoms. An upper gastrointestinal tract barium-contrast radiographic examination was performed at 1 year to assess for recurrence. Demographic factors, comorbidities, and preoperative radiographic findings were analyzed as possible indicators for recurrence using logistic regression.Quality of life, measured by the gastroesophageal reflux disease-specific QOL tool, and recurrence, defined as a PEH of greater than 2 cm.Median patient age was 61 years, 63.1% of patients were women, and 81.1% of patients were white. Four patients required reoperation, of which only 1 was for symptomatic recurrent PEH. The mean follow-up time for the 36-month QOL assessment was 43.5 months. The overall preoperative and 2-, 12-, and 36-month QOL scores were 28.50, 10.18, 9.74, and 10.58, respectively (P .001). Recurrences were found in 19 of the 70 patients (27%) who completed the 1-year radiographic examination. Compared with baseline, all individual symptoms improved significantly except for early satiety (mean [SD] score, 3.18 [1.88] at baseline vs 2.07 [1.70] at the 36-month follow-up; P = .07), nausea (1.69 [1.63] vs 0.77 [1.25]; P = .08), pain with swallowing (1.06 [1.50] vs 0.53 [0.90]; P = .73), and bloating/gas (3.28 [1.71] vs 2.23 [1.72]; P = .05) at the 36-month QOL assessment. Although not statistically significant, preoperative hernias containing most of the stomach were more likely to recur after repair when compared with those involving gastric cardia and fundus (odds ratio, 3.74 [95% CI, 0.93-15.14]; P = .06).Overall, laparoscopic repair of PEH with biological mesh results in excellent long-term QOL. The cause of recurrence is likely multifactorial and individualized to each patient. Further evaluation of novel techniques and unidentified patient factors is needed.

Wrong-site surgery can be a catastrophic event for a patient, caregiver, and institution. Although communication breakdowns have been identified as the leading cause of wrong-site surgery, the efficacy of preventive strategies remains unknown. This study evaluated the impact of operating room briefings on coordination of care and risk for wrong-site surgery.We administered a case-based version of the Safety Attitudes Questionnaire (SAQ) to operating room (OR) staff at an academic medical center, before and after initiation of an OR briefing program. Items questioned overall coordination and awareness of the surgical site. Response options ranged from 1 (disagree strongly) to 5 (agree strongly). MANOVA was used to compare caregiver assessments before and after the implementation of briefings, and the percentage of OR staff agreeing or disagreeing with each question was reported.The prebriefing response rate was 85% (306 of 360 respondents), and the postbriefing response rate was 75% (116 of 154). Respondents included surgeons (34.9%), anesthesiologists (14.0%), and nurses (44.4%). Briefings were associated with caregiver perceptions of reduced risk for wrong-site surgery and improved collaboration [F (6,390)=10.15, p0.001]. Operating room caregiver assessments of briefing and wrong-site surgery issues improved for 5 of 6 items, eg, "Surgery and anesthesia worked together as a well-coordinated team" (67.9% agreed prebriefing, 91.5% agreed postbriefing, p0.0001), and "A preoperative discussion increased my awareness of the surgical site and side being operated on" (52.4% agreed prebriefing, 64.4% agreed postbriefing, p0.001).OR briefings significantly reduce perceived risk for wrong-site surgery and improve perceived collaboration among OR personnel.

Gaining access to a surgical site via retracting neighboring tissue can result in complications due to occlusion of the tissue blood supply resulting in ischemic damage. By incorporating oxygenation sensors on the working surfaces of surgical retractors and graspers, it is possible to measure the local tissue oxygen saturation and look for trends in real-time. Further, by measuring tissue interaction forces simultaneously, we can further augment the information available to the surgeon. The sensors provide a means for sensory substitution to help compensate for the decreased sensation present in minimally invasive laparoscopic and robotic procedures that are gaining significant popularity. Sensing surgical instruments will allow for safer and more effective surgeries while not interfering with the normal workflow of a procedure

Paragangliomas of the organ of Zuckerkandl are rare tumors with only several case reports noted in the literature. Synchronous paraganglioma occur sporadically, and on occasion, in association with several genetic syndromes. Paraganglioma of the organ of Zuckerkandl with synchronous carotid body paraganglioma is described herein. Traditionally, surgical resection of abdominal paraganglioma involved an exploratory laparotomy. In this manuscript, we describe one of the first reported laparoscopic resections of this tumor and review the literature on multiple paragangliomas and their associated genetic syndromes.

We have shown that the inflammation-attenuating effects of CO(2) pneumoperitoneum during laparoscopy are not due to changes in systemic pH. However, acidification of peritoneal macrophages in an in vitro CO(2) environment has been shown to reduce LPS-mediated cytokine release. We tested the hypothesis that the peritoneum is locally acidotic during abdominal insufflation with CO(2)--even when systemic pH is corrected. Rats (n = 20) were anesthetized and randomized into two groups: continued spontaneous ventilation (SV) or intubation and mechanical ventilation (MV). All animals were then subjected to abdominal insufflation with CO(2). Mean arterial pH among SV rats decreased significantly from baseline after 15 and 30 minutes of CO(2) pneumoperitoneum (7.329 --7.210 --7.191, P0.05), while arterial pH among MV rats remained relatively constant (7.388 --7.245 --7.316, P = NS). In contrast, peritoneal pH dropped significantly from baseline and remained low for both groups during CO(2) abdominal insufflation (SV 6.74 --6.41 --6.40, P0.05; MV 6.94 --6.45 --6.45, P0.05). In a second experiment, rats (n = 10) were randomized to receive abdominal insufflation with either CO(2) or helium. Abdominal insufflation with helium did not significantly affect peritoneal pH (7.10 --7.02 --6.95, P = NS), and the decrease in pH among CO(2)-insufflated animals was significant compared with helium-insufflated animals (P0.05). Peritoneal pH returned to baseline levels in all groups within 15 minutes of desufflation in both experiments. A significant local peritoneal acidosis occurs during laparoscopy which is specifically attributable to the use of CO(2) and which is independent of systemic pH. These data provide additional evidence that localized peritoneal acidosis is central to the mechanism of CO(2)-mediated attenuation of the inflammatory response following laparoscopic surgery.

The purpose of this study was to determine if systemic acidosis induced by peritoneal absorption of carbon dioxide (CO2 ) during laparoscopy plays a role in CO2 pneumoperitoneum-mediated attenuation of the acute phase inflammatory response associated with perioperative sepsis. The influence of hepatic polymorphonuclear (PMN) leukocyte infiltration on this phenomenon was also investigated.Forty-five rats were randomized into 5 groups: anesthesia control, open cecal ligation and puncture (OCLP), laparoscopic cecal ligation and puncture using helium for insufflation (He LCLP), LCLP using CO2 with continued spontaneous ventilation (LCLP-SV), and LCLP using CO2 with intubation and positive pressure ventilation (LCLP-PPV).After 30 minutes, arterial blood gas parameters remained normal in control, OCLP rats, and He LCLP rats, while CO2 LCLP-SV rats developed significant hypercarbic acidosis. This acidosis was corrected in CO2 LCLP-PPV rats ( P.0001 vs CO2 LCLP-SV for both). Expression of the rat acute phase gene alpha 2 -macroglobulin was greater after OCLP and He LCLP than after either CO2 LCLP-SV or CO2 LCLP-PPV ( P.0001 vs either CO2 OCLP-SV for both). However, levels of alpha 2 -macroglobulin were not significantly different between the acidotic (LCLP-SV) and normocarbic (LCLP-PPV) CO2 groups. Infiltration of the hepatic parenchyma by PMNs did not differ significantly between groups.CO2 insufflation-induced systemic acidosis is not responsible for the reduction in the acute phase inflammatory response observed in laparoscopic animal models of sepsis. Hepatic PMN infiltration also does not appear to mediate this effect.

Carbon dioxide (CO(2)) pneumoperitoneum alters the inflammatory response in animal models of sepsis. The spleen is a key organ in inflammation and its removal was predicted to modify this effect.The acute phase inflammatory response to lipopolysaccharide (LPS) challenge in male rats was examined for the effects of splenectomy (spx) and the technique of removal (open or laparpscopic). A series of experiments compared LPS-only controls with LPS injection 2 or 9 days following open spx, lap CO2 spx, open sham, or lap CO2 sham. The method of splenectomy was studied by randomization to control, open spx, lap CO2 spx, lap helium (He) spx, or lap air spx with LPS challenge on postoperative day 2. Serum levels of tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (INF-gamma) and, interleutin (IL) 10 were collected at multiple time points, assayed by commercial enzyme-linked immunosorbent assay, analyzed by analysis of variance.Levels of TNF-alpha at 1.5 were significantly lower following open sham than following lap sham (p0.05). Splenectomy drastically reduced INF-gamma and TNF-alpha levels compared to controls (p0.05) on postoperative day 2. No method of spx preserved TNF-alpha or INF-gamma responses. Recovery of TNF-alpha response on day 9 was delayed in the spx groups.Splenectomy dramatically reduces TNF-alpha and INF-gamma responses to LPS challenge, although by different mechanisms. Pneumoperitoneum-mediated modulation of the septic inflammatory response is partially dependent on the spleen.

We report results from a single surgeon’s 10-year team experience with laparoscopic total abdominal colectomy. We review our series, which includes a large subgroup of ill, high-risk patients with acute colitis requiring urgent surgery. From 1993 to 2003, we performed 65 laparoscopic total abdominal colectomies. All patients referred for total abdominal colectomy were offered the laparoscopic approach. We prospectively collected the following data on all patients: demographics, surgical indications, preoperative status, duration of surgery, intraoperative blood loss, operative complications, length of stay, subsequent operations, patient satisfaction, and lessons learned from our team experience. Preoperative diagnoses included ulcerative colitis (n = 55), Crohn’s colitis (n = 3), colonic inertia (n = 4), and familial adenomatous polyposis (n = 3). Among the patients with inflammatory bowel disease, 70% of cases were performed on ill patients, refractory to medical management, requiring urgent surgery. This subgroup was managed with laparoscopic total abdominal colectomy and Brooke ileostomy, with ileoanal pouch anastomosis deferred. Operative times were long, ranging from 6 to 11 hours. Mean intraoperative blood loss was 200 ml. Mean length of stay was 4.3 days and ranged from 2 to 13 days. There were no conversions to open surgery and there were no deaths. Complications occurred in 12% of patients and included intra-abdominal abscess (n = 2), wound infection (n = 3), stoma stenosis (n = 1), and incisional hernia (n = 2). Postoperative patient satisfaction was high. Subsequent operations, including restorative proctectomy, were also performed laparoscopically. Laparoscopic total abdominal colectomy is technically challenging and requires a team approach but offers patients significant benefit in length of stay and surgical recovery. This operation can be effectively used with minimal morbidity in difficult, ill patients requiring urgent surgery.

Peritoneal absorption of CO(2) during abdominal insufflation in laparoscopy may disrupt the acid-base equilibrium and alter the physiological response to stress. Current nonventilated rodent models of laparoscopy do not manage the CO(2) load of pneumoperitoneum, but ventilated surgical rodent models are invasive (tracheotomy) and may independently induce the inflammatory response.A comprehensive rodent model of laparoscopy was developed. Rats were randomized to receive anesthesia alone, anesthesia plus CO(2) pneumoperitoneum, or anesthesia plus CO(2) pneumoperitoneum with videoendoscopic intubation and mechanical ventilation. Arterial blood-gas analysis was performed at baseline and after 30 min of intervention.Baseline pH, pCO(2), and HCO(3)(-) arterial blood gas parameters were normal for all rats. After 30 min, pCO(2) and pH changed slightly but remained normal among rats receiving anesthesia alone (pCO(2) = 46.5 +/- 1.9; pH = 7.365 +/- 0.009) whereas animals receiving anesthesia plus CO(2) pneumoperitoneum that were dependent on spontaneous respiration for ventilation developed significant hypercarbic acidosis (pCO(2) = 53.2 +/- 1.9, P0.05; pH = 7.299 +/- 0.011, P0.001). This acidosis was completely corrected with increased minute ventilation in intubated rats receiving mechanical ventilation (pCO(2) = 36.8 +/- 1.5, P0.001; pH = 7.398 +/- 0.011, P0.001).CO(2) pneumoperitoneum induces significant hypercarbic acidosis in nonventilated rats. Noninvasive endotracheal intubation is feasible in the rat with videoendoscopic assistance. Our noninvasive rodent model of laparoscopic surgery controls for anesthesia- and capnoperitoneum-related acid-base changes and provides an environment in which the biological response to pneumoperitoneum can be studied precisely.

The daVinci surgical system affords surgeons a magnified three-dimensional videoscopic view of the operative field and precise articulating laparoscopic instruments. The learning curve for this advanced surgical robotics system is poorly characterized.Twenty-three surgeons representing seven surgical subspecialties participated in a surgical robotics training program consisting of standardized daVinci system training (phase 1) followed by self-guided learning in a porcine model (phase 2).The average number of recorded procedures performed per surgeon during phase 2 was 5.5. The mean daVinci system set-up time was 45 minutes and decreased by an average of 56.1% by the third successive set-up (r = -0.702, P0.005). Operative times decreased 39.0% by the third successive practice operation (r = -0.860, P0.0005).New use of the daVinci robot is associated with a rapid learning curve and preclinical animal model training is effective in developing surgical robotics skills.

Introduction L’etancheite d’une suture doit pouvoir etre appreciee apres chirurgie endoscopique transviscerale (NOTES) afin de prevenir la contamination postoperatoire de la cavite peritoneale. L’hydrogene (H 2 ) est un gaz non toxique, non inflammable a basse concentration, volatile et detectable. Objectif Evaluer un test d’etancheite a l’H 2 pour la NOTES transgastrique. Materiels et Methodes Une NOTES transgastrique standardisee (creation d’un pneumoperitoine au CO 2 a travers une aiguille minilaparoscopique, ponction transgastrique a l’aiguille de coupe, dilation au ballonnet de 20 mm, peritoneoscopie souple, suture endoscopique) etait realisee chez 21 porcs. Le test d’etancheite consistait a 1) insuffler endoscopiquement l’estomac a l’H 2 (dilution a 4 %, volume 1 000 ml, pression 30 mmHg) ; 2) prelever un echantillon de 20 ml de pneumoperitoine a travers l’aiguille minilaparoscopique ; 3) analyser la concentration intraperitoneale en H 2 (CIPH 2 ) ; 4) exsuffler le pneumoperitoine. Dans une serie d’experiences sans survie (9 animaux), des tests a l’H 2 etaient repetes aux differentes etapes de l’intervention (basal, post-ponction, avant fermeture) et apres suture de l’abord transgastrique. La suture etait realisee par 2 paires de points en T de facon aleatoirement complete (2 points serres) ou incomplete (1 point serre, 1 lâche). Une necropsie avec test au bleu de methylene (BM) etait realisee. Dans une serie d’experiences avec survie (12 animaux), l’abord transgastrique etait ferme par clips ou points serres, puis un test a l’H 2 realise. Les resultats du test a l’H 2 etaient compares a l’evaluation endoscopique et necropsique a 15 jours. Resultats Les peritoneoscopies et sutures endoscopiques etaient realisees avec succes chez les 21 animaux. Les echantillonages et mesures de CIPH 2 (donnees en ppm) etaient realisees en moins de 2 minutes. Experiences sans survie : les CIPH 2 etaient similaires entre les 2 groupes avant ponction (0,18 ± 0,29 vs 0,22 ± 0,35, p = 0,97) et avant suture (414,8 ± 198,5 vs 601,3 ± 116,1, p > 0,99). Apres suture complete, la CIPH 2 etait significativement plus basse qu’en cas de suture complete incomplete (0,01 ± 0,77 vs 162,0 ± 83,0, p 2 a 25 ppm determinait une correlation parfaite avec les resultats du test au BM. Experiences avec survie : Le test a l’H 2 etait negatif chez 11 animaux (moyenne 4,3 ± 8,1), positif chez 1 animal (106,7 ppm). Aucun animal ne developpait de complication postoperatoire. L’endoscopie et la necropsie confirmaient l’integrite de la fermeture de la gastrotomie chez les 12 animaux. La specificite et la valeur predictive negative du test etaient de 100 % et 95 %, respectivement. Conclusion Le test d’etancheite a l’H 2 est un outil non-invasif, rapide, quantitatif et specifique, adapte a la NOTES. Remerciements, financements, autres Xavier Dray remercie la SNFGE, l’AGA et l’AP-HP.

Abdominal surgery is now commonly accomplished laparoscopically using carbon dioxide (CO 2 ) insufflation. Increased intraabdominal pressure (IAP) decreases hepatic blood flow, portal vein pressure, and hepatic pH. Furthermore, CO 2 pneumoperitoneum worsens systemic acidosis. Liver function tests (LFTs) are often elevated following laparoscopic cholecystectomy albeit without any clinical significance. Helium (He) may be an alternative to CO 2 pneumoperitoneum. We examined effects of IAP and the potential benefits afforded by He pneumoperitoneum on hepatocellular toxicity. Fifty male Sprague-Dawley rats were randomized to anesthesia control, CO 2 pneumoperitoneum at 4 mmHg, CO 2 pneumoperitoneum at 8 mmHg, CO 2 pneumoperitoneum at 12 mmHg, and Helium pneumoperitoneum at 12 mmHg. Rats received pneumoperitoneum or control procedure for 30 min. Alkaline phosphatase (AlkPhos), alanine aminotransferase (ALT), and aspartate aminotransferase (AST) were measured at baseline, 2 h, and 24 h following pneumoperitoneum. Helium increased ALT and AST at 2 h compared to all other groups. By 24 h AST was elevated in all groups except the He group. These differences between He and all other groups were not seen in AlkPhos. CO 2 pneumoperitoneum did not cause a significant change in LFTs compared to control regardless of changes in IAP, at any time point. Helium pneumoperitoneum acutely increases AST and ALT without altering AlkPhos. These results imply that hepatocellular function is altered by He without significantly influencing biliary function, thus suggesting a highly specific mechanism of action. Furthermore, CO 2 pneumoperitoneum does not cause hepatocellular damage in the acute postoperative period regardless of IAP. TABLE—ABSTRACT P81 . Alk Phos ALT AST t = 0 t = 2 h t = 24 h t = 0 t = 2 h t = 24 h t = 0 t = 2 h t = 24 h Control 200 193 219 42 42 48 74 78 137 CO 2 4 mmHg 217 189 198 34 30 35 73 78 118 CO 2 8 mmHg 278 268 319 41 39 40 76 82 115 CO 2 12 mmHg 221 215 248 44 42 44 78 90 138 He 12 mmHg 248 215 243 37 55 34 68 109 77

Despite their high cost, surgical robotic systems continue to gain prominence in the operating room. In this study, the initial performance of a diverse population of surgeons and surgical residents with no previous surgical robotics experience was characterized. The objectives of this study were (1) To compare the initial performance of different surgical robotic systems; (2) To determine the inter-robot transferability of skills acquired on a surgical robot; and (3) To determine if differences exist in the initial robotic surgery learning curve among surgeons of varying levels of surgical experience. A multi-institutional group of 38 surgeons and 28 surgeons-in-training were evaluated using three surgical skill tests: “paper cut,” “ring swap,” and “thread the needle.” Every participant was timed on each of two robots, Intuitive Surgical’s daVinci Surgical System and endoVia’s Laprotek System. The order in which the subjects were tested on each of the two robots was determined at random. Composite scores representing participant performance on each of the two robots and overall performance were calculated. The “paper cut” test took participants twice as long and the “ring swap” test took over three times as long on the Laprotek robot compared to the daVinci robot ( P P P P

Anesthetics attenuate cytokine production in various models of endotoxic shock. Few studies have shown the effect of anesthetics on the ultimate end-point, death. The literature suggests Isoflurane can inhibit the onset but not the progression of the inflammatory cascade. Thus, we hypothesize that Isoflurane will increase survival of rats receiving a lethal dose (LD50) of bacterial lipopolysaccharide (LPS) and that this protective effect requires that Isoflurane be given before the endotoxic insult. The effect of Isoflurane on mortality was studied by inducing sepsis using the LD50 of LPS in male Sprague-Dawley rats. Rats were fasted and then randomized into 4 groups: Isoflurane 2 h before LPS, Isoflurane and LPS simultaneously, or Isoflurane 2 h after LPS. All 3 groups received 30 min of Isoflurane 2%. The fourth group received LPS alone without any durable exposure to Isoflurane. Rats were observed for survival. Isoflurane pretreatment increased survival by 30% compared to LPS alone and was significantly better compared to simultaneous or posttreatment (P < 0.011). Rats that received Isoflurane simultaneously with or after LPS had 20% less survival then rats in the LPS alone group. Isoflurane is recognized as having potent anti-inflammatory effects. These effects can significantly increase survival in the rat model of sepsis. The protective effect of Isoflurane necessitates administration prior to the inflammatory insult. The use of Isoflurane may be useful in critical care patients who face a profound septic risk such as burn victims. Download full-size image

Introduction. CO 2 pneumoperitoneum is known to have beneficial immune effects in laparoscopic surgery. However, the effects of CO 2 pneumoperitoneum preconditioning on the immune response to conventional surgery are unknown. The purpose of this study was to determine if CO 2 pneumoperitoneum preconditioning would reduce the cytokine response to lipopolysaccharide (LPS) sepsis and laparotomy. Materials and Methods. Thirty-two rats ( n = 8) were randomized into four groups: CO 2 pneumoperitoneum, helium pneumoperitoneum, anesthesia control, and laparotomy/LPS only control. The first three groups received 30 min of preconditioning with their respective treatments followed by laparotomy for another 30 min. Simultaneously to laparotomy, rats received intraperitoneal Escherichia coli LPS (1 mg/kg). The laparotomy/LPS only control group received no preconditioning. In a second experiment, 40 rats ( n = 10) were subjected to the same conditions described above but with the laparotomy being closed immediately following LPS injection. Blood samples for serum cytokine assays were collected via cardiac puncture from all animals 2 h following LPS injection. Results. Compared to laparotomy/LPS only control, plasma levels of IL-6 were depressed 30% by anesthesia preconditioning, 55% by He-pneumoperitoneum preconditioning, and 84% by CO 2 -pneumoperitoneum preconditioning. In the second experiment, IL-6 levels were depressed 8.9% by anesthesia-preconditioning, 9.6% by He-pneumoperitoneum, and 49% by CO 2 -pneumoperitoneum compared to laparotomy/LPS only control. Conclusions. CO 2 pneumoperitoneum preconditioning down regulates subsequent serum IL-6 expression in response to LPS-induced sepsis even in the setting of a laparotomy. Furthermore, the immune modulating effects of CO 2 pneumoperitoneum endure for a number of hours following abdominal insufflation regardless of the duration of open peritoneal exposure to the ambient environment. CO 2 pneumoperitoneum preconditioning may protect the critically ill surgery patient from the inflammatory response associated with sepsis and surgical celiotomy.

Application of radiofrequency ablative techniques to thyroid disease could result in treatments that are nontoxic, thyroid sparing, and minimally invasive. The purpose of this pilot study was to evaluate the safety of radiofrequency ablation (RFA) of thyroid tissue in a porcine model. Eight euthyroid Yorkshire pigs weighing 35–45 kg were randomized to control or ultrasound-guided central thyroid RFA at three doses: 500, 1000, or 2000 J. Animals were evaluated for signs of recurrent laryngeal nerve damage. Serum thyroid hormone levels were assayed in all animals at baseline and postprocedurally at 24 h, 96 h, and weekly for 6 weeks. Total thyroidectomy was performed 6 weeks post-RFA. None of the animals in this study suffered pathologic recurrent laryngeal nerve damage. Free T4 levels were not elevated in any animal at any time point in this study. Mean weight gain among these rapidly growing pediatric pigs was 18 kg in the 6 weeks following RFA or control procedure and was similar between groups. Post-RFA histology revealed localized necrosis with normal appearing surrounding thyroid tissue. Ultrasound-guided RFA in the thyroid gland is feasible and safe. Application of up to 2000 J of radiofrequency energy in normal thyroid tissue does not cause thyrotoxicosis. Given the proven track record of radiofrequency ablative techniques in other tumor types, clinical trials evaluating the efficacy of RFA technology in benign human thyroid disease are warranted.