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Dive into the research topics where Hans J. Schmidt is active.

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Featured researches published by Hans J. Schmidt.


Surgical Endoscopy and Other Interventional Techniques | 2003

Laparoscopic Roux-en-Y gastric bypass

David Oliak; Garth H. Ballantyne; P. Weber; Annette Wasielewski; Richard J Davies; Hans J. Schmidt

Background: Increasing numbers of laparoscopic surgeons are performing laparoscopic Roux-en-Y gastric bypass (LGB). Our aim was to determine the length of the learning curve for a skilled laparoscopic surgeon. Methods: The study population consisted of the first 225 consecutive LGB procedures attempted by one laparoscopic surgeon (HJS). Outcome parameters included mortality, morbidity, operative time, and conversion to an open procedure. Results: Average operative time decreased from 189 min (first 75 patients) to 125 minutes (last 75 patients). Most of the improvement in operative time occurred over the first 75 patients. The perioperative complication rate decreased from 32% (first 75 patients) to 15% (second and third groups of 75 patients). Complication rates did not significantly decrease after the first 75 patients. Low mortality and conversion rates were achieved early in the series. Conclusion: Low mortality rates and low conversion rates can be achieved early in the learning curve for LGB. Complication rates plateau after approximately 75 LGBs, and operative times decrease substantially over the initial 75 cases. Operative times continue to decrease at a slower rate beyond 75 cases.


Obesity Surgery | 2002

Short-Term Results of Laparoscopic Gastric Bypass in Patients with BMI ≥60

David Oliak; Garth H. Ballantyne; Richard J Davies; Annette Wasielewski; Hans J. Schmidt

Background: Laparoscopic Roux-en-Y gastric bypass (LRYGBP) has been shown to be safe and effective. Little information is available about the subgroup of patients with BMI ≥60. The goal of this study was to evaluate the feasibility and safety of LRYGBP for patients with BMI ≥60. Methods: The study consisted of the first 300 attempted LRYGBPs performed by one surgeon (HJS). This population was analyzed as 2 groups of patients: those with BMI <60 and those with BMI ≥60. Outcome variables included mortality, complications, conversion, and operative time. Results: Of the first 300 LRYGBP patients, 261 had BMI <60 and 39 had BMI ≥60. Age, comorbidity rate, and gender distribution were similar in both BMI groups. Conversion rates were <3% in both groups. Mean operative time for the BMI ≥ 60 group was 156 minutes vs 139 minutes in the lighter group (P=0.04). Major complications occurred more commonly in the BMI ≥60 group (10% vs 6%) but this difference was not significant. The types of complications differed between the 2 groups, with infectious complications and gastrointestinal leak occurring more frequently in the heavier group. The mortality rate was higher in the heavier group (5% vs 0.4%, P=0.055). Conclusion: LRYGBP is feasible for patients with BMI ≥60. Our data suggest that these patients are at a higher risk for GI leak, postoperative infection, and death.


Obesity Surgery | 2004

Predictors of Prolonged Hospital Stay following Open and Laparoscopic Gastric Bypass for Morbid Obesity: Body Mass Index, Length of Surgery, Sleep Apnea, Asthma and the Metabolic Syndrome

Garth H. Ballantyne; Jonathan Svahn; Rafael F. Capella; Joseph F. Capella; Hans J. Schmidt; Annette Wasielewski; Richard J Davies

Background: The number of weight reduction operations performed for type II and type III obesity is rapidly escalating. Risk of surgery has been infrequently stratified for patient subgroups. The purpose of this study was to identify patient characteristics that increased the odds of a prolonged hospital length of stay (LOS) following open or laparoscopic Roux-en-Y gastric bypass (RYGBP). Methods: The hospital records of 311 patients who underwent RYGBP in a 6-month period were retrospectively reviewed. Patient characteristics including the presence of significant obesity-related medical conditions were recorded. Analysis was based on intent to treat. Univariate and step-wise logistic regression analysis was used to identify the odds ratio (OR) and adjusted odds ratio (AOR) for predictors of an increased hospital LOS. Results: Datasets for 311 patients were complete. 159 patients underwent open vertical banded gastroplasty-Roux-en-Y gastric bypass (VBG-RYGBP) and 152 laparoscopic RYGBP (LRYGBP). 78% of patients were female. Median age was 40 years (range 18-68). Median BMI was 49 kg/m2 (range 35-82). 17% of patients had sleep apnea, 18% asthma, 19% type 2 diabetes, 13% hypercholesterolemia and 44% hypertension. Median length of surgery for open VBG-RYGBP (64 minutes) was significantly faster than for LRYGBP (105 minutes). Median length of stay was significantly shorter for LRYGBP (2 days) than open VBG-RYGBP (3 days). Univariate logistic regression analysis identified 6 predictors of increased LOS: open surgery (0.4 OR); increasing BMI (60 kg/m2 0.38 OR; BMI 70 kg/m2 0.53 OR); increasing length of surgery (120 min 0.33 OR; 180 min 0.48 OR); sleep apnea (2.25 OR); asthma (3.73 OR); and hypercholesterolemia (3.73 OR). Subset analysis identified patients with the greatest odds for a prolonged hospital stay: women with asthma (2.47 AOR) or coronary artery disease (8.65 AOR); men with sleep apnea (5.54 OR) or the metabolic syndrome (6.67 – 10.20 OR); and patients undergoing a laparoscopic operation with sleep apnea (11.53 AOR) or coronary artery disease (12.15 AOR). Conclusions: Open surgery, BMI, length of surgery, sleep apnea, asthma and hypercholesterolemia all increased the odds of a prolonged LOS. Patients with the greatest odds of long LOS were women with asthma or coronary disease, men with sleep apnea or the metabolic syndrome, and patients undergoing laparoscopic surgery with sleep apnea or coronary artery disease. Patients at high-risk for prolonged hospital stay can be identified before undergoing RYGBP. Surgeons may wish to avoid high-risk patients early in their bariatric surgery experience.


Obesity Surgery | 2004

Impact of Fellowship Training on the Learning Curve for Laparoscopic Gastric Bypass

David Oliak; Milton Owens; Hans J. Schmidt

Background: We have previously shown that the learning curve for laparoscopic Roux-en-Y gastric bypass (LRYGBP) is approximately 75 cases. Patients have worse outcomes during the learning curve. Our aim was to evaluate the impact of fellowship training on outcomes during a surgeons early experience with LRYGBP. Methods: The study population consisted of the first 75 consecutive LRYGBP operations attempted by two laparoscopic surgeons, one with laparoscopic gastric bypass fellowship training (Group A) and one without laparoscopic bypass fellowship training (Group B). Outcome parameters included mortality, major perioperative complications, operative time, and conversion to an open operation. Results: Age, BMI, and gender distribution were similar in both groups. Operative time was significantly longer in Group B (189 min. vs 122 min., P <0.05). Conversion to an open procedure occurred uncommonly in both groups (3%). Major complications occurred more frequently in Group B (13% vs 8%, P =NS). In addition, the complications in Group B were more severe, resulting in 2 deaths. No deaths occurred in Group A. Conclusion: Laparoscopic gastric bypass fellowship training improves perioperative outcomes during a surgeons early experience with LRYGBP.


Obesity Surgery | 2005

The Learning Curve Measured by Operating Times for Laparoscopic and Open Gastric Bypass: Roles of Surgeon's Experience, Institutional Experience, Body Mass Index and Fellowship Training

Garth H. Ballantyne; Douglas R. Ewing; Rafael F. Capella; Joseph F. Capella; Daniel Davis; Hans J. Schmidt; Annette Wasielewski; Richard J Davies

Background: Surgeons must overcome a substantial learning curve before mastering laparoscopic Rouxen-Y gastric bypass (LRYGBP). This learning curve can be defined in terms of mortality, morbidity or length of surgery. The aim of this study was to compare the learning curves in terms of surgical time for the first 3 surgeons performing LRYGBP in our hospital with the length of surgery for open gastric bypass (CONTROLS). Methods: We compared 494 primary LRYGBPs performed by 3 surgeons (393 by 1st SURGEON, 57 by 2nd SURGEON and 44 by 3rd SURGEON) to 159 open vertical banded gastroplasty-Roux-en-Y gastric bypasses (CONTROLS). Data for LRYGBP patients were prospectively recorded while those for CONTROLS were retrospectively obtained. Factors that significantly affected the length of surgery were identified by univariate and multivariate linear regression analysis. Results: LRYGBP and CONTROL patients were similar in age, height, weight and BMI, although more CONTROLS were male. Median time for the 1st SURGEON performing LRYGBP dropped for each subsequent 100 operations: 1st 100 – 190 min, 2nd 100 – 135 min, 3rd 100 – 110 min and 4th 100 – 100 min. Median time for the 2nd SURGEON performing LRYGBP was 120 min, 3rd SURGEON 173 min and CONTROLS 64 min. Length of surgery significantly correlated with surgical experience in terms of number of operations and BMI of patient. Times for 2nd SURGEON, a fellowship trained laparoscopic surgeon, started significantly faster than 1st SURGEONs, but did not significantly improve with experience. 3rd SURGEONs initial times were similar to 1st SURGEONs, but his times improved more rapidly with experience. Times for CONTROLS were significantly faster than all laparoscopic groups and did not correlate with operation number or patient BMI. Conclusions: The length of surgery for LRYGBPs continued to shorten beyond 400 operations for the first surgeon performing LRYGBP in our hospital. Previous fellowship training in LRYGBP shortened surgical times during initial clinical experience as an attending for the second surgeon. The learning curve for a subsequent experienced laparoscopic surgeon was truncated because of the already established LRYGBP program.


Surgery for Obesity and Related Diseases | 2008

Short-term outcomes for super-super obese (BMI ≥60 kg/m2) patients undergoing weight loss surgery at a high-volume bariatric surgery center: laparoscopic adjustable gastric banding, laparoscopic gastric bypass, and open tubular gastric bypass

Daniel J. Stephens; John K. Saunders; Scott Belsley; Amit Trivedi; Douglas R. Ewing; Vincent A. Iannace; Rafael F. Capella; Annette Wasielewski; S. Moran; Hans J. Schmidt; Garth H. Ballantyne

BACKGROUND We previously reported significantly longer operating room times and a trend toward increased complications and mortality in the super-super obese (body mass index [BMI] > or =60 kg/m(2)) early in our experience with laparoscopic Roux-en-Y gastric bypass. The goal of this study was to re-examine the short-term outcomes for super-super obese patients undergoing weight loss surgery at our high-volume bariatric surgery center well beyond our learning curve. METHODS The records for all patients who had undergone weight loss surgery at Hackensack University Medical Center from 2002 to June 2006 were harvested from the hospitals electronic medical database. This population was analyzed as 2 groups (those with a BMI <60 kg/m(2) and those with a BMI > or =60 kg/m(2)), as well as by type of operation. Step-wise and univariate logistic regression analyses assessed the effect of BMI on the outcome variables, including mortality, length of surgery, length of hospital stay, and disposition at discharge. RESULTS A total of 3692 patients were studied. Of these patients, 3401 had a BMI <60 kg/m(2) and 291 had a BMI > or =60 kg/m(2). Of the 291 super-super obese patients, 130 underwent vertical banded gastroplasty-Roux-en-Y gastric bypass, 116 laparoscopic Roux-en-Y gastric bypass, and 45 laparoscopic adjustable gastric banding. The proportion of male patients, black patients, and patients with sleep apnea was increased in the BMI > or =60 kg/m(2) group. The number of co-morbid diseases per patient correlated with age but not BMI. The BMI > or =60 kg/m(2) group required a significantly longer total operating room time (136 versus 120 min). Hospital length of stay was significantly longer only in the laparoscopic Roux-en-Y gastric bypass patients (3 d for the BMI > or =60 kg/m(2) group versus 2 d for the BMI <60 kg/m(2) group). A significantly greater percentage of patients in the super-super obese group were discharged to chronic care facilities. The overall in-hospital mortality rate was 0.15% (5 of 3692) but did not significantly differ between the 2 groups: BMI <60 kg/m(2), rate of 0.12% (4 of 3401 patients), and BMI > or =60 kg/m(2), rate of 0.34% (1 of 291 patients). The type of operation did not significantly affect the disposition at discharge or in-hospital mortality. CONCLUSION Super-super obese patients required longer total operating room times, a longer hospital length of stay, and were more likely to be discharged to chronic care facilities than were patients with a BMI <60 kg/m(2); however, the in-hospital mortality was similar for both groups.


Obesity Surgery | 2005

Patient Characteristics Impacting Excess Weight Loss following Laparoscopic Adjustable Gastric Banding

Wai Yip Chau; Hans J. Schmidt; Wael Kouli; Daniel Davis; Annette Wasielewski; Garth H. Ballantyne

Background: Weight loss is more variable after laparoscopic adjustable gastric banding (LAGB) than after gastric bypass. Subgroup analysis of patients may offer insight into this variability. The aim of our study was to identify preoperative factors that predict outcome. Methods: Demographics, co-morbid conditions and follow-up weight were collected for our 1st 200 LapBand ® patients. Linear regression determined average %EWL. Logistic regression analysis identified factors that impacted %EWL. Result: 200 patients returned for 778 follow-up visits. Median age was 44 years (21-72) and median BMI 45 kg/m2 (31-76). 140 (80%) were women. Average %EWL was y % = 0.007 %/day (days since surgery) + 0.12% (correlation coef. 0.4823; P<0.001). %EWL at 1 year was 37%. The best-fit logistic regression model found 7 factors that significantly changed the odds of achieving average %EWL. Older patients, diabetic patients and patients with COPD had greater odds of above average %EWL. Female patients, patients with larger BMIs, asthmatic patients and patients with hypertension had increased odds of below average %EWL. Conclusion: Specific patient characteristics and comorbid conditions significantly altered the odds of achieving satisfactory %EWL following gastric banding.


Surgery for Obesity and Related Diseases | 2018

Large series examining laparoscopic adjustable gastric banding as a salvage solution for failed gastric bypass

Hans J. Schmidt; Edmund W. Lee; Erica Amianda; Themba Nyirenda; Toghrul Talishinskiy; Richard C. Novack; Douglas R. Ewing

BACKGROUND The Roux-en-Y gastric bypass (RYGB) has long been considered the gold standard of weight loss procedures. However, there is limited evidence on revisional options with both minimal risk and long-term weight loss results. OBJECTIVE To examine percent excess weight loss, change in body mass index (BMI), and complications in patients who underwent laparoscopic adjustable gastric banding (LAGB) over prior RYGB. SETTING Academic hospital. METHODS Retrospective analysis of a single-center prospectively maintained database. Three thousand ninety-four LAGB placements were reviewed; 139 were placed in patients with prior RYGB. RESULTS At the time of LAGB, the median BMI was 41.3. After LAGB, we observed weight loss or stabilization in 135 patients (97%). The median maximal weight loss after LAGB was 37.7% excess weight loss and -7.1 change in BMI (P < .0001). At last follow-up visit, the median weight loss was 27.5% excess weight loss and -5.3 change in BMI (P < .0001). Median follow-up was 2.48 years (.01-11.48): 68 of 132 eligible (52%) with 3-year follow-up, 12 of 26 eligible (44%) with 6-year eligible follow-up, and 3 of 3 eligible (100%) with >10-year follow-up. Eleven bands required removal, 4 for erosion, 4 for dysphagia, and 3 for nonband-related issues. CONCLUSIONS LAGB over prior RYGB is a safe operation, which reduces the surgical risks and nutritional deficiencies often seen in other accepted revisional operations. Complication rates were consistent with primary LAGB. Weight loss is both reliable and lasting, and it can be considered as the initial salvage procedure in patients with failed gastric bypass surgery.


Obesity Surgery | 2007

One-year Readmission Rates at a High Volume Bariatric Surgery Center: Laparoscopic Adjustable Gastric Banding, Laparoscopic Gastric Bypass, and Vertical Banded Gastroplasty-Roux-en-Y Gastric Bypass

John K. Saunders; Garth H. Ballantyne; Scott Belsley; Daniel J. Stephens; Amit Trivedi; Douglas R. Ewing; Vincent A. Iannace; Rafael F. Capella; Annette Wasileweski; Steven Moran; Hans J. Schmidt


Obesity Surgery | 2008

Bariatric Surgery: Low Mortality at a High-Volume Center

Garth H. Ballantyne; Scott Belsley; Daniel J. Stephens; John K. Saunders; Amit Trivedi; Douglas R. Ewing; Vincent A. Iannace; Daniel Davis; Rafael F. Capella; Annette Wasielewski; S. Moran; Hans J. Schmidt

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Douglas R. Ewing

Hackensack University Medical Center

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Amit Trivedi

Hackensack University Medical Center

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Garth H. Ballantyne

Hackensack University Medical Center

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Annette Wasielewski

Hackensack University Medical Center

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Rafael F. Capella

Hackensack University Medical Center

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Sebastian Eid

Hackensack University Medical Center

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Richard Novack

Hackensack University Medical Center

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George Mazpule

Hackensack University Medical Center

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Richard J Davies

Hackensack University Medical Center

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Toghrul Talishinskiy

Hackensack University Medical Center

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