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Dive into the research topics where Georg O. Spaun is active.

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Featured researches published by Georg O. Spaun.


Annals of Surgery | 2011

Randomized controlled trial comparing single-port laparoscopic cholecystectomy and four-port laparoscopic cholecystectomy.

Jun Ma; Maria A. Cassera; Georg O. Spaun; Chet W. Hammill; Paul D. Hansen; Shaghayegh Aliabadi-Wahle

Objective:To compare short-term surgical outcomes and quality of life (QOL) between single-port laparoscopic cholecystectomy (SPLC) and classic 4-port laparoscopic cholecystectomy (CLC). Background:There is significant interest in further reducing the trauma associated with surgical procedures. Although a number of observational studies have suggested that SPLC is a feasible alternative to CLC, there is a lack of data from randomized studies validating any benefit over CLC. Methods:Eligible patients were randomized to receive SPLC or CLC. Operative and perioperative outcomes, including cosmesis and QOL were analyzed. Results:Forty-three patients were randomized to SPLC (n = 21) or CLC (n = 22). There were no significant differences between groups for most preoperative demographics, American Society of Anesthesiology score, gallstone characteristics, local inflammation, blood loss, or length of stay. Patients undergoing SPLC were older than those receiving CLC (57.3 years vs. 45.8 years, P < 0.05). Operative times for SPLC were greater than CLC (88.5 minutes vs. 44.8 minutes, P < 0.05). Overall and cosmetic satisfaction, QOL as determined by the SF-36 survey, postoperative complications, and post-operative pain scores between discharge and 2-week postoperative visit were not significantly different between groups. Wound infection rates were similar in both groups. The SPLC group contained 1 retained bile duct stone, 1-port site hernia, and 1 postoperative port site hemorrhage. Conclusions:SPLC procedure time was longer and incurred more complications than CLC without significant benefits in patient satisfaction, postoperative pain and QOL. SPLC may be offered in carefully selected patients. Larger randomized trials performed later in the learning curve with SPLC may identify more subtle advantages of one method over another.


Gastrointestinal Endoscopy | 2009

Bimanual coordination in natural orifice transluminal endoscopic surgery: comparing the conventional dual-channel endoscope, the R-Scope, and a novel direct-drive system

Georg O. Spaun; Bin Zheng; Danny V. Martinec; Maria A. Cassera; Christy M. Dunst; Lee L. Swanstrom

BACKGROUND The devices used for natural orifice transluminal endoscopic surgery procedures are endoscopes or inspired by endoscopic design, which makes it difficult to accomplish bimanual coordination. OBJECTIVE We evaluated 3 operating systems in simulated natural orifice transluminal endoscopic surgery procedures requiring complex bimanual coordination. DESIGN Operators were required to perform an identical bimanual task by using 3 operating systems: a dual-channel endoscope (DCE); the R-Scope, which has 2 elevators for independent movement of endoscopic instruments; and the Direct Drive Endoscopic System (DDES), which allows separation of instruments and vision, emulating more of a laparoscopic surgery paradigm. SETTING A bench-top simulation was used. Twelve teams were recruited for DCE and R-Scope testing. Twelve individuals participated in the DDES setup. The task included 3 steps: picking up a ring, passing it between endoscopic instruments, and placing it on a designated location. MAIN OUTCOME MEASUREMENTS Task performance was evaluated by movement speed and accuracy. RESULTS Task performance was significantly faster when using the DDES system (29 +/- 28 seconds) compared with the other operating systems (DCE: 140 +/- 55 seconds, R-Scope: 160 +/- 71 seconds; P < .001). The difference between the DCE and the R-Scope was not significant (P = .370). CONCLUSION Designs that separate vision and motion have more degrees of freedom at the tip of the instruments, and an ergonomic user interface provides benefits for bimanual performance compared with more traditional endoscopic designs. With the DDES, a single operator can perform complex endoscopic tasks faster than 2 operators with a DCE or R-Scope.


Gastrointestinal Endoscopy | 2010

Endoscopic closure of gastrogastric fistulas by using a tissue apposition system (with videos)

Georg O. Spaun; Danny V. Martinec; Timothy J. Kennedy; Lee L. Swanstrom

BACKGROUND Gastrogastric fistulas (GGFs) are seen in 1.5% to 12.5% of patients after Roux-en-Y gastric bypass (RYGB) bariatric surgery, often leading to failure to lose adequate weight. OBJECTIVE The aim of this study was to assess the feasibility, safety, and percentage of successful primary endoluminal closures of GGFs by using a recently developed tissue apposition system in combination with local mucosectomy. DESIGN A feasibility and outcome study following institutional review board protocol. SETTING Tertiary referral teaching hospital, Legacy Health System, Portland, Oregon. INTERVENTIONS A combination of mucosectomy and nonresorbable tissue apposition is used to achieve a permanent closure of the GGF. PATIENTS Four patients with 5 GGFs after RYGB; the mean fistula diameter of was 18.6 mm (range 10-30 mm). RESULTS Primary closure rate (1 endoscopic session) of 5 GGFs was 100%. The mean procedure time was 88.5 minutes. One to 4 pairs of tissue anchors were used to close the fistulas. The mean time for performing mucosectomy was 21.6 minutes (range 8-42 minutes) and 39.6 minutes (range 12-58 minutes) for fistula closure. Estimated blood loss was on average 2 mL (range 0-5 mL). No complications were recorded. Early success (3 months), as evidenced by early satiety and weight loss, was noted for 3 of 4 patients. After 3 months, only the smallest fistula (10 mm) was still completely closed, and after 6 months, it also showed a pinhole opening. CONCLUSION It was feasible to close all fistulas endoscopically without complications. Permanent closure of GGFs could not be achieved.


Gastrointestinal Endoscopy | 2013

Subjective and objective data on esophageal manometry and impedance pH monitoring 1 year after endoscopic full-thickness plication for the treatment of GERD by using multiple plication implants

Oliver O. Koch; Adolf Kaindlstorfer; Stavros A. Antoniou; Georg O. Spaun; Rudolph Pointner; Lee L. Swanstrom

BACKGROUND Subjective and especially objective data after endoluminal full-thickness gastroplication are scarce. OBJECTIVE To evaluate symptoms and reflux activity 12 months after gastroplication by using multichannel intraluminal impedance monitoring. DESIGN Open-label, prospective, single-center study. SETTING Tertiary referral hospital in Zell am See, Austria. PATIENTS Subjects without hiatal hernias with documented GERD and persistent or recurrent symptoms despite treatment with a proton pump inhibitor. INTERVENTIONS A total of 36 patients underwent endoscopic full-thickness gastroplication with 1 or more Plicator implants. MAIN OUTCOME MEASUREMENTS Mean Gastrointestinal Quality of Life Index and reflux-specific symptom scores significantly improved on follow-up (P < .01). Atypical reflux, gas/bloating, and bowel dysfunction-specific symptom scores as well as belching and dysphagia scores improved. Twenty-two patients returned for esophageal manometry and multichannel intraluminal impedance testing 1 year after surgery. DeMeester scores decreased from 20 to 10 (P < .029). The median numbers of total, acid, proximal, upright, and recumbent reflux episodes were all significantly reduced (P < .05). Manometric data were virtually unchanged. The percentage of patients taking proton pump inhibitors on daily basis after the procedure was 11.5%. There was only 1 postprocedure incident (bleeding) that required intervention. Three of 36 patients (8.3%) were considered treatment failures because of persistent symptoms and were assigned to undergo laparoscopic fundoplication. LIMITATIONS No randomized comparison with a sham procedure or laparoscopic fundoplication; follow-up interval. CONCLUSIONS Endoscopic plication is safe and improves objective and subjective parameters at 1-year follow-up, without side effects seen after laparoscopic fundoplication. Further studies on the clinical merit of this procedure in specific patient populations are warranted.


Surgical Endoscopy and Other Interventional Techniques | 2010

Use of flexible endoscopes for NOTES: sterilization or high-level disinfection?

Georg O. Spaun; Trudie A. Goers; Richard A. Pierce; Maria A. Cassera; Sandy Scovil; Lee L. Swanstrom

BackgroundNatural orifice translumenal endoscopic surgery (NOTES) involves the use of flexible endoscopes to perform intra-abdominal or intra-thoracic surgeries. Surgery in the operating room usually involves sterile instrumentation, whereas in the endoscopy suite high-level disinfection seems to be sufficient. Our objective was to assess the necessity for endoscope sterilization for clinical NOTES and to develop an endoscope processing protocol based on a score for the available processing options.MethodsScore and processing protocol development for clinical NOTES endoscopes was based on a comprehensive review of the available relevant literature. Options for sterilization for flexible endoscopes in the Good Samaritan Hospital, Legacy Health in Portland, Oregon, were analyzed for patient safety, potential for recontamination, cost, and validation.ResultsLiterature survey indicated that there is controversy surrounding the necessity for sterilization of surgical endoscopes. However, standard of practice seems to call for sterile instrumentation for surgery and it is possible to terminally sterilize flexible endoscopes. Within our institution, a score was created to rank the available sterilization options. We successfully introduced a protocol for sterilization of endoscopes for use in clinical NOTES procedures. The protocol involved mechanical cleaning and high-level disinfection per Multi-Society Guidelines, with subsequent terminal sterilization using a validated peracetic acid protocol.ConclusionsIt remains controversial whether sterile instrumentation is truly needed for surgery. It is difficult but possible to terminally sterilize flexible endoscopes. We recommend sterile instrumentation for clinical NOTES until well-designed, randomized, clinical trials are available and guidelines are published.


Journal of Gastrointestinal Surgery | 2010

Transcervical Heller Myotomy Using Flexible Endoscopy

Georg O. Spaun; Christy M. Dunst; Brittany N. Arnold; Danny V. Martinec; Maria A. Cassera; Lee L. Swanstrom

IntroductionEsophageal achalasia is most commonly treated by laparoscopic myotomy. Transesophageal approaches using flexible endoscopy have recently been described. We hypothesized that using techniques and flexible instruments from our NOTES experience through a small cervical incision would be a safer and less traumatic route for esophageal myotomy. The purpose of this study was to evaluate the feasibility, safety, and success rate of using flexible endoscopes to perform anterior or posterior Heller myotomy via a transcervical approach.MethodsThis animal (porcine) and human cadaver study was conducted at the Legacy Research and Technology Center. Mediastinal operations on ten live, anesthetized pigs and two human cadavers were performed using standard flexible endoscopes through a small incision at the supra-sternal notch. The esophagus was dissected to the phreno-esophageal junction using balloon dilatation in the peri-esophageal space followed by either anterior or posterior distal esophageal myotomy. Success rate was recorded of esophageal dissection to the diaphragm and proximal stomach, anterior and posterior myotomy, perforation, and complication rates.ResultsDissection of the esophagus to the diaphragm and performing esophageal myotomy was achieved in 100% of attempts. Posterior Heller myotomy was always extendable onto the gastric wall, while anterior gastric extension of the myotomy was found to be more difficult (4/4 and 2/8, respectively; P = 0.061).ConclusionHeller myotomy through a small cervical incision using flexible endoscopes is feasible. A complete Heller myotomy was performed with a higher success rate posteriorly possibly due to less anatomic interference.


Surgical Endoscopy and Other Interventional Techniques | 2013

Endoscopic grading of the gastroesophageal flap valve is correlated with reflux activity and can predict the size of the esophageal hiatus in patients with gastroesophageal reflux disease

Oliver O. Koch; Georg O. Spaun; Stavros A. Antoniou; Charlotte Rabl; Gernot Köhler; K Emmanuel; Dietmar Öfner; Rudolph Pointner

BackgroundEndoscopic grading of the gastroesophageal flap valve (GEFV) is simple, reproducible, and suggested to be a good predictor of reflux activity. This study aimed to investigate the potential correlation between grading of the GEFV and quality of life (QoL), gastroesophageal reflux disease (GERD) symptoms, esophageal manometry, multichannel intraluminal impedance monitoring (MII) data, and size of the hiatal defect.MethodsThe study included 43 patients with documented chronic GERD who underwent upper gastrointestinal endoscopy, esophageal manometry, and ambulatory MII monitoring before laparoscopic fundoplication. The GEFV was graded 1–4 using Hill’s classification. QoL was evaluated using the Gastrointestinal Quality-of-Life Index (GIQLI), and gastrointestinal symptoms were documented using a standardized questionnaire. The size of the esophageal hiatus was measured during surgery by calculating the hiatal surface area (HSA). Analysis of the correlation between QoL, GERD symptoms, esophageal manometry, MII data, HSA size, and GEFV grading was performed. Statistical significance was set at a p value of 0.05.ResultsA significant positive correlation was found between increased GEFV grade and DeMeester score, total number of acid reflux events, number of reflux events in the supine position, and number of reflux events in the upright position. Additionally, a significant positive correlation was found between HSA size and GEFV grading. No significant influence from intensity of GERD symptoms, QoL, and the GEFV grading was found. The mean LES pressures were reduced with increased GEFV grade, but not significantly.ConclusionsThe GEFV plays a major role in the pathophysiology of GERD. The results underscore the importance of reconstructing a valve in patients with GERD and an altered geometry of the gastroesophageal junction when they receive a laparoscopic or endoscopic intervention.


Surgical Endoscopy and Other Interventional Techniques | 2010

Mediastinal surgery in connective tissue tunnels using flexible endoscopy

Georg O. Spaun; Christy M. Dunst; Danny V. Martinec; Brittany N. Arnold; M. Owens; Lee L. Swanstrom

BackgroundMediastinal surgery most often is performed via a transthoracic or transabdominal approach; however, the pre- and paratracheal mediastinum can be readily accessed with a transcervical approach. The purpose of this study was to evaluate the feasibility, safety, and success rate of using a transcervical approach and flexible endoscopes to perform mediastinal surgery also in the retro- and paraesophageal mediastinum.MethodsMediastinal operations on four live pigs and one human cadaver were performed using standard endoscopes through a small cervical incision. The procedure involved marking of four mediastinal lymph nodes using endoscopic ultrasound (EUS). The esophagus was dissected to the phrenoesophageal junction by creating connective tissue tunnels with balloon dilatation and low-pressure CO2 insufflation. Heller myotomy was performed followed by sequential identification and removal of the marked nodes. Success rate of esophageal dissection to the diaphragm, Heller myotomy, directed mediastinal lymph node harvest, and complication rates were evaluated.ResultsDissection of the esophagus to the diaphragm was achieved in 100% of attempts. Distal esophageal myotomy was performed in all cases. Harvest of marked lymph nodes (ln) was successful in 100% of animals (16/16 ln) and cadavers (2/2 ln). One major complication was recorded in the pig group (tension pneumomediastinum).ConclusionsThe entire visceral mediastinum can be successfully accessed through a transcervical incision using flexible endoscopes. Directed lymph node harvest and esophageal myotomy is feasible with a high success rate. Connective tissue tunnels are safe, atraumatic, and a promising concept for targeted mediastinal exploration. With refinement in technology, this approach may be useful for a variety of mediastinal surgeries.


Surgical Innovation | 2011

Efficacy of using a novel endoscopic lens cleaning device: a prospective randomized controlled trial.

Maria A. Cassera; Trudie A. Goers; Georg O. Spaun; Lee L. Swanstrom

Introduction. Clear visualization of the surgical field is critical in laparoscopic surgery. The authors evaluated a device that does not necessitate an external cleaning process for the laparoscope. It was hypothesized that it will minimize the interruption in operative workflow. Methods. A total of 40 advanced laparoscopy patients were randomized to either the control or device group. Demographic data, procedural data, length of stay, frequency and duration of lens cleaning, and lens clarity scores (LCS) were recorded. Independent samples t test and Fisher’s exact test were performed. Results . No significant difference was found between the device and control groups in demographic data, procedure time (P = .922) or LCS (P = .124). Laparoscope cleaning in the device group was significantly shorter than in the control group (P < .001). No complications were observed. Conclusion. An intra-abdominal laparoscopic cleaning device can effectively clean the laparoscopic lens and lead to less workflow interruption. Although not documented in this study, it may also lead to shorter operative times.


United European gastroenterology journal | 2017

Photodynamic therapy with polyhematoporphyrin for malignant biliary obstruction: A nationwide retrospective study of 150 consecutive applications

Werner Dolak; Hubert Schwaighofer; Brigitte Hellmich; Bernhard Stadler; Georg O. Spaun; W Plieschnegger; Arnold Hebenstreit; Jutta Weber-Eibel; Franz Siebert; Klaus Emmanuel; Peter Knoflach; Michael Gschwantler; Wolfgang Vogel; Michael Trauner; Andreas Püspök

Background Photodynamic therapy (PDT) is a palliative treatment for malignant biliary obstruction. Objective The objective of this article is to assess the feasibility and safety of this technique. Methods In this nationwide, retrospective study of prospectively collected clinical data, all patients treated with PDT using polyhematoporphyrin in Austria from March 2004 to May 2013 were included. Feasibility, adverse events, stent patency and mortality rates were investigated. Results Eighty-eight patients (54 male, 34 female, median age 69 years) underwent 150 PDT procedures at seven Austrian referral centers for biliary endoscopy. The predominant underlying disease was Klatskin tumor (79/88). All PDT procedures were feasible without technical issues. Cholangitis was the most frequent adverse event (21/88). Stent patency was 246 days (95% CI 203–289) median and was significantly longer for metal than for plastic stents (269 vs. 62 days, p < 0.01). The median survival was 12.4 months (95% CI 9.7–14.9 m) calculated from first PDT and 15.6 months (95% CI 12.3–18.7 m) calculated from initial diagnosis. In patients suffering from biliary tract cancer, Cox regression revealed the number of PDT treatment sessions as the only independent predictor of survival at a multivariate analysis (p = 0.048). Conclusion PDT using polyhematoporphyrin was feasible and safe in this nationwide analysis. Survival data suggest a benefit of PDT in this unselected real-life patient population. Prospective trials comparing PDT to other palliative treatments will help to define its role in the management of malignant biliary obstruction. The study is registered at ClinicalTrials.gov number: NCT02504957.

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Lee L. Swanstrom

Providence Portland Medical Center

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Oliver O. Koch

Innsbruck Medical University

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Andreas Tschoner

University of Rochester Medical Center

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K Emmanuel

University of Innsbruck

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