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Dive into the research topics where Klaus Thaler is active.

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Featured researches published by Klaus Thaler.


Journal of The American College of Surgeons | 2008

Use of Endoscopic Stents to Treat Anastomotic Complications after Bariatric Surgery

Steve Eubanks; Christopher A. Edwards; Nicole Fearing; Archana Ramaswamy; Roger de la Torre; Klaus Thaler; Brent W. Miedema; James S. Scott

BACKGROUND Complications after bariatric surgery often require longterm parenteral nutrition to achieve healing. Recently, endoscopic treatments have become available that provide healing while allowing for oral nutrition. The purpose of this study was to present outcomes of the largest series to date treating staple line complications after bariatric surgery with endoscopic covered stents. STUDY DESIGN A retrospective evaluation was performed of all patients treated for staple line complications after bariatric surgery at a single tertiary care bariatric center. Acute postoperative leaks, chronic gastrocutaneous fistulas, and anastomotic strictures refractory to endoscopic dilation after both gastric bypass and sleeve gastrectomy were included. RESULTS From January 2006 to June 2007, 19 patients (11 with acute leaks, 2 with chronic fistulas, and 6 with strictures) were treated with a total of 34 endoscopic silicone covered stents (23 polyester, 11 metal). Mean followup was 3.6 months. Immediate symptomatic improvement occurred in 90% (91% of acute leaks, 100% of fistulas, and 84% of strictures). Oral feeding was started in 79% of patients immediately after stenting. Resolution of leak or stricture after stent treatment occurred in 16 of 19 patients (84%). Healing of leak, fistula, and stricture occurred at means of 33 days, 46 days, and 7 days, respectively. Three patients (1 with leak, 1 with fistula, and 1 with stricture) had unsuccessful stent treatment. Migration of the stent occurred in 58% of 34 stents placed. Most migration was minimal, but three stents were removed surgically after distal small bowel migration. There was no mortality. CONCLUSIONS Treatment of anastomotic complications after bariatric surgery with endoscopic covered stents allows rapid healing while simultaneously allowing for oral nutrition. The primary morbidity is stent migration.


Journal of The American College of Surgeons | 2009

Single-Incision Laparoscopic Cholecystectomy Using Conventional Instruments: Early Experience in Comparison with the Gold Standard

Scott Reynold Philipp; Brent W. Miedema; Klaus Thaler

BACKGROUND The aim of this pilot study was to describe our initial experience with single-incision laparoscopic cholecystectomy (SILC) using conventional laparoscopic equipment in comparison with concurrent patients undergoing conventional multiincision laparoscopic cholecystectomy. STUDY DESIGN During the 7-month study period, data from all consecutive patients undergoing SILC by two surgeons were retrospectively analyzed and compared with data from patients undergoing conventional laparoscopic cholecystectomy by the same surgeons during the same time period. Outcomes measures included completion rate of attempted SILC, operative time, length of hospital stay, postoperative pain, and assessment of complications. RESULTS From 51 laparoscopic cholecystectomies performed during the study period, 29 were attempted using single-incision technique and 22 were performed using the conventional four incisions. Of the attempted SILC cases, 14 (48%) were successfully completed, with the remainder requiring one to three additional skin incisions. There were no conversions to open in either group. Operative time was significantly longer in SILC cases compared with conventional laparoscopic cholecystectomy (85 versus 67 minutes; p = 0.01). There was a tendency toward greater postoperative pain in the SILC group. No substantial difference in complications was identified. CONCLUSIONS SILC using conventional laparoscopic instrumentation is an effective alternative to standard four-incision laparoscopic cholecystectomy in selected patients. Development of a standardized technique and additional experience is needed for more consistent success. Additional studies of SILC are needed to demonstrate safety, define selection criteria, and determine any benefits over conventional laparoscopic cholecystectomy.


Diseases of The Colon & Rectum | 2003

Determinants of Recurrence After Sigmoid Resection for Uncomplicated Diverticulitis

Klaus Thaler; M. K. Baig; Mariana Berho; Eric G. Weiss; Juan J. Nogueras; J.P. Arnaud; Steven D. Wexner; Roberto Bergamaschi

AbstractPURPOSE: This study aimed to evaluate the impact of surgery-associated variables on recurrence rates after sigmoid resection for diverticulitis. METHODS: Patients who underwent elective sigmoid resection for uncomplicated diverticulitis between 1992 and 2000 at two tertiary referral centers were followed up for recurrent disease as the primary end point. Recurrence after surgery was defined as left lower quadrant pain, fever, and leukocytosis, with consistent CT and/or contrast enema findings on admission and after six weeks. A logistic regression of the following variables was undertaken: patient demographics, duration of preoperative symptoms, previous admissions and abdominal surgery, surgical access (laparoscopic or open), postoperative complications, splenic flexure mobilization, anastomotic technique (handsewn or stapled), specimen length, inflammation at proximal resection margin, and anastomotic level (colosigmoid or colorectal). The last three variables were defined by the pathologist. Anastomosis level was based on muscle layer configuration (taeniae coli) at the distal resection margin. RESULTS: Two hundred thirty-six patients (105 females) with a mean age of 60.4 (standard deviation, ± 10) years were available for follow-up at 67 ± 30 (range, 11–130) months. The median duration of preoperative symptoms was 18 (range, 12–120) months. All but one (99 percent) patient had at least one admission before surgery. One hundred forty (59 percent) and 96 (41 percent) patients underwent laparoscopic or open resection, respectively. The conversion rate was 13 percent (18 patients) in the former group and the 30-day complication rate was 23 percent, with 0.4 percent 30-day mortality and a 2.1 percent reoperation rate. The splenic flexure was mobilized in 109 patients (47 percent). Anastomoses were fashioned by stapler in 171 patients (73 percent) and were to the rectum in 143 patients (72 percent). Specimen length was 17.9 ± 5.9 (range, 9–47) cm with inflammation at the proximal margin in 30 patients (14 percent). Twelve (5 percent) patients developed a recurrence at a mean of 78 ± 25 (range, 34–109) months with reoperation in one (0.4 percent). The level of anastomosis was the only predictor of recurrence in regression analysis (P = 0.033). Patients with colosigmoid anastomosis had a four times higher risk of having a recurrence compared with patients with colorectal anastomosis (odds ratio, 95 percent confidence interval = 1.12, 14.96). CONCLUSION: Colorectal (rather than colosigmoid) anastomosis was the single predictor of lower recurrence rates after elective sigmoid resection for uncomplicated diverticulitis.


Journal of The American College of Surgeons | 2009

Laparoscopic Appendectomy—Is it Worth the Cost? Trend Analysis in the US from 2000 to 2005

Emanuel Sporn; Gregory F. Petroski; Gregory J. Mancini; J. Andres Astudillo; Brent W. Miedema; Klaus Thaler

BACKGROUND Although laparoscopic appendectomy is widely used for treatment of appendicitis, it is still unclear if it is superior to the open approach. STUDY DESIGN From the Nationwide Inpatient Sample 2000 to 2005, hospitalizations with the primary ICD-9 procedure code of laparoscopic (LA) and open appendectomy (OA) were included in this study. Outcomes of length of stay, costs, and complications were assessed by stratified analysis for uncomplicated and complicated appendicitis (perforation or abscess). Regression methods were used to adjust for covariates and to detect trends. Costs were rescaled using the hospital and related services portion of the Medical Consumer Price Index. RESULTS Between 2000 and 2005, 132,663 (56.3%) patients underwent OA and 102,810 (43.7%) had LA. Frequency of LA increased from 32.2% to 58.0% (p < 0.001); conversion rates decreased from 9.9% to 6.9% (p < 0.001). Covariate adjusted length of stay for LA was approximately 15% shorter than for OA in both uncomplicated and complicated cases (p < 0.001). Adjusted costs for LA were 22% higher in uncomplicated appendicitis and 9% higher in patients with complicated appendicitis (p < 0.001). Costs and length of stay decreased over time in OA and LA. The risk for a complication was higher in the LA group (p < 0.05, odds ratio=1.07, 95% CI 1.00 to 1.14) with uncomplicated appendicitis. CONCLUSIONS LA results in higher costs and increased morbidity for patients with uncomplicated appendicitis. Nevertheless, LA is increasingly used. Patients undergoing LA benefit from a slightly shorter hospital stay. In general, open appendectomy may be the preferred approach for patients with acute appendicitis, with indication for LA in selected subgroups of patients.


Colorectal Disease | 2005

Assessment of long-term quality of life after laparoscopic and open surgery for Crohn's disease

Klaus Thaler; Adam Dinnewitzer; Michael Oberwalder; Eric G. Weiss; Juan J. Nogueras; S. D. Wexner

Objective  Surgery for Crohns disease (CD) is associated with a high recurrence rate and quality of life (QOL) in these patients is controversial. The aim of this study was to assess QOL in patients after laparoscopic and open surgery for CD by two different validated instruments, a generic nonspecific score and a specific gastrointestinal QOL index.


Surgical Endoscopy and Other Interventional Techniques | 2003

Long-term outcome and health-related quality of life after laparoscopic and open colectomy for benign disease

Klaus Thaler; Adam Dinnewitzer; E. Mascha; S. Arrigain; Eric G. Weiss; Juan J. Nogueras; Steven D. Wexner

Background: The benefits of laparoscopic colectomy (LC) vs open colectomy (OC) for the treatment of benign disease have not yet been clearly demonstrated with regard to long-term consequences and health-related quality of life (HRQL). The aim of this study was to compare LC and OC in terms of outcome and HRQL and to determine whether a generic nonspecific instrument for HRQL assessment is valid in postoperative follow-up. Methods: Forty-nine patients who underwent LC for elective right hemicolectomy (RH) or sigmoid resection (SR) for benign polyps or uncomplicated diverticular disease between 1992 and 2000 were evaluated and compared to 50 controls treated by OC in the same period. All patients were evaluated by postal questionnaire to determine recurrence rates and surgery-related complications. HRQL was assessed by the SF-36 Physical and Mental Component Summary Score (PCS, MCS) and by the SF-36 Health Survey, which measures eight different health-quality domains, including physical and social functioning (PF, SF), general health perception (GH), physical and emotional role limitations (RP, RE), body pain (BP), vitality (VT), and mental health (MH). Results: The LC and OC patients were similar in age, gender, body mass index (BMI), American Society of Anesthesiologists (ASA) classification, and diagnosis. There were significant differences between the two groups in resection type (26 RH:23 SR in LC vs 16 RH:34 SR in OC, p = 0.03) and length of follow-up (median, 39 and 53.5 months, respectively, p = 0.04), but neither parameter was predictive of the main SF-36 scores (PCS and MCS). There were no differences between the groups in recurrence rates (8% in LC vs 11% in OC) or surgery-related complications, including incisional hernias (16.3% in LC vs 17% in OC) and small bowel obstructions (2% in LC vs 10.4% in OC). None of the eight SF-36 Health Survey domains or the PCS or MCS scores showed significant differences between LC and OC patients in HRQL. However, occurrence of hernia after surgery was predictive of lower SF-36 scores, specifically in PF (p = 0.047), GH (p = 0.045), SF (p = 0.047), MH (p = 0.041), and MCS (p = 0.037). In addition, small bowel obstruction was significantly associated with lower scores in BP (p = 0.008), GH (p = 0.008), SF (p = 0.013), RE (p = 0.026), MH (p = 0.003), and MCS (p = 0.003). Conclusion: LC was not different from OC for selected indications that measure long-term outcome and HRQL. SF-36 appears to be an appropriate instrument to measure postoperative HRQL, showing responsiveness to changes in objective outcome measures.


Surgical Laparoscopy Endoscopy & Percutaneous Techniques | 2003

Recurrence Rates at Minimum 5-year Follow-up: Laparoscopic Versus Open Sigmoid Resection for Uncomplicated Diverticulitis

Klaus Thaler; Eric G. Weiss; Juan J. Nogueras; Jean-Pierre Arnaud; Steven D. Wexner; Roberto Bergamaschi

The aim of the study was to compare the impact of surgical access to sigmoid resection on recurrence rates in patients with uncomplicated diverticulitis of the sigmoid (UDS) at a minimum follow-up of 5 years. Recurrence after surgery was defined as left lower quadrant pain, fever, and leucocytosis with consistent CT and enema findings on admission and at 6 weeks, respectively. Outcome measures included splenic flexure mobilization, specimen length, inflammation at proximal resection margin, and presence of teniae coli at distal resection margin. Seventy-nine patients undergoing laparoscopic sigmoid resection (LSR) were compared with 79 matched controls with open sigmoid resection (OSR) operated on at 2 institutions during the same period. Patients were well matched for age, gender, body mass index, ASA grading, and symptoms duration, but not for follow-up length (81.9 versus 86.9 months, P = 0.046). Differences in rates of splenic flexure mobilization (19 versus 41, P < 0.001), specimen length (16.1 versus 18.3 cm, P = 0.048), inflammation at proximal resection margin (21 versus 4, P < 0.001), and teniae coli at distal resection margin (4 versus 53, P < 0.001) did not show an impact on recurrence rates when comparison was made between LSR and OSR. Three LSR patients and 7 OSR patients had 1 recurrence (P = 0.19). There were no significant differences in rates of flexure mobilization, specimen length, and rates of inflammation present at proximal resection margin in 10 recurring and 145 non-recurring patients. The rate of teniae coli present at distal resection margin was significantly increased in recurring patients (7 versus 43, P = 0.03). Median time of recurrence after surgery was 29 (range 18–74) months. Two of 11 recurrences occurred after 5 years. Surgical access to sigmoid resection for UDS is unlikely to have an impact on recurrence rates provided that the oral bowel end is anastomosed to the proximal rectum rather than to the distal sigmoid.


Journal of The American College of Surgeons | 2008

Nationwide Impact of Laparoscopic Lysis of Adhesions in the Management of Intestinal Obstruction in the US

Gregory J. Mancini; Gregory F. Petroski; Wen Chieh Lin; Emanuel Sporn; Brent W. Miedema; Klaus Thaler

BACKGROUND Treatment of adhesion-related complications is cost intensive and presents a considerable burden to the health care system. The objective of this study was to compare open (OLA) and laparoscopic lysis of adhesions (LLA) in the treatment of intestinal obstruction, based on a nationwide representative sample. STUDY DESIGN Patients with intestinal obstruction undergoing OLA, LLA, and conversion were identified from the 2002 National Inpatient Sample. After propensity methods were used to adjust for covariates including patient demographics, hospital characteristics, and comorbidities, the impact of OLA and LLA was analyzed concerning in-hospital mortality, postoperative complications, length of stay (LOS), and in-hospital costs. RESULTS Of 6,165 patients, 88.6% underwent OLA and 11.4% had LLA. Conversion was required in 17.2% of LLA patients. Unadjusted mortality was equal between LLA and conversion (1.7%) and half the rate compared with OLA (3.4%) (p = 0.014). After adjusting with propensity methods, the odds of complications in the LLA group (intention to treat) were 25% less than in the OLA (p = 0.008). The LLA group had a 27% shorter LOS (p = 0.0001) and was 9% less expensive than the OLA group (p = 0.0003). There was no statistical significant difference for LOS, complications, and costs between the conversion and OLA groups. CONCLUSIONS Results from this study suggest that when LLA is applied to selected patients with intestinal obstruction, there are reductions in postoperative complications, LOS, and costs. Prospective studies are needed to confirm these data and better identify the subgroup of patients who have improved outcomes with LLA.


American Journal of Surgery | 2010

How should we establish the clinical case numbers required to achieve proficiency in flexible endoscopy

Melina C. Vassiliou; Pepa Kaneva; Benjamin K. Poulose; Brian J. Dunkin; Jeffrey M. Marks; Riadh Sadik; Gideon Sroka; Mehran Anvari; Klaus Thaler; Gina L. Adrales; Jeffrey W. Hazey; Jenifer R. Lightdale; Vic Velanovich; Lee L. Swanstrom; John D. Mellinger; Gerald M. Fried

BACKGROUND Recommended procedure numbers for upper endoscopy (UE) and colonoscopy (C) are 35 and 50 for surgical residents, and 130 and 140 for gastroenterology fellows, respectively. The purpose of this study was to challenge the methods used to determine proficiency in flexible endoscopy. METHODS Global assessment of gastrointestinal endoscopic skills (GAGES) was used to evaluate 139 procedures. Scores for UE were compared using self-reported case numbers and grouped according to requirements for each discipline. C scores were compared using the requirements to define novice and experienced endoscopists. Procedure volumes were plotted against GAGES scores. RESULTS Three groups were compared for UE based on case volumes: fewer than 35 cases (group 1), 35 to 130 cases (group 2), and more than 130 cases (group 3). There was no difference between group 2 (17.8 +/- 1.8) and group 3 (19.1 +/- 1.1), but both scored higher than group 1 (14.4 +/- 3.7; P < .05). For C, the scores were 11.8 +/- 3.8 (novices) and 18.8 +/- 1.34 (experienced; P < .001) at a 50-case minimum and 12.4 +/- 4.2 and 18.8 +/- 1.3 (P < .001) for a 140-case proficiency cut-off level, respectively. The curve of procedures versus GAGES plateaued at 50 (UE) and 75 (C). CONCLUSIONS The surgical and gastroenterology case recommendations may not represent the experience needed to achieve proficiency. GAGES scores could help define proficiency in basic endoscopy.


Surgery for Obesity and Related Diseases | 2008

Management of anastomotic leaks after Roux-en-Y bypass using self-expanding polyester stents

Christopher A. Edwards; J. Andres Astudillo; Roger de la Torre; Brent W. Miedema; Archana Ramaswamy; Nicole Fearing; Bruce Ramshaw; Klaus Thaler; J. Stephen Scott

BACKGROUND To analyze the outcomes of a series of endoscopically placed polyester self-expanding polyflex stents (SEPSs) for the management of anastomotic leaks after Roux-en-Y bypass. Anastomotic leaks after gastric bypass cause significant morbidity and mortality. Covered polyester SEPSs might have a role in the treatment of these leaks. METHODS A retrospective chart review was performed from January 2006 to November 2006 that included all acute and chronic leaks treated with SEPSs. RESULTS A total of 6 patients were treated with stents, with a mean procedure time of 22 minutes. Of these 6 patients, 5 had acute postoperative leaks and 1 had a chronic fistula. Five patients started oral intake 1-6 days after their procedure. All acute leaks had complete healing at a median of 44 days. The patient with a chronic gastrocutaneous fistula required revisional surgery for fistula closure. In addition, 5 patients had stent migration, and 3 required stent replacement. CONCLUSION An endoscopically placed SEPS provides a less-invasive alternative to treat acute anastomotic leaks after Roux-en-Y bypass while simultaneously allowing oral intake. The results of this case series have demonstrated this treatment to be safe and effective.

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