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Dive into the research topics where Alexander Klaus is active.

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Featured researches published by Alexander Klaus.


Journal of Gastrointestinal Surgery | 2001

Five- to eight-year outcome of the first laparoscopic Nissen fundoplications.

Tanja Bammer; Ronald A. Hinder; Alexander Klaus; Paul J. Klingler

The operative mortality and morbidity of laparoscopic fundoplication are lower than for the open procedure. Questions have been raised regarding its long-term durability. One hundred seventy-one patients who had undergone laparoscopic Nissen fundoplication at least 5 years previously answered a questionnaire. During this period, 291 patients underwent a laparoscopic Nissen fundoplication. Surveillance data were available for 171 patients at a mean of 6.4 years after surgery. Overall, 96.5% were satisfied and 3.5% were not satisfied with the result of the procedure. Persistent symptoms included abdominal bloating (20.5%), diarrhea (12.3%), regurgitation (6.4%), heartburn (5.8%) and chest pain (4.1%); 27.5% reported dysphagia, and 7% had required dilatation. Fourteen percent were on continuous proton pump inhibitor therapy, but 79% of these patients were treated for vague abdominal or chest symptoms unrelated to reflux, which calls into question the indications for this therapy. Ninety-three percent of all patients were satisfied with their decision to have surgery. The overall well-being score increased significantly from 2.2 ±1.6 before surgery to 8.8 ±2 (P >0.0001) at more than 5 years after surgery. Twenty-one percent had undergone additional diagnostic procedures after surgery such as endoscopy and/or barium swallow. Laparoscopic Nissen fundoplication is an excellent long-term treatment for gastroesophageal reflux disease with persistent success for more than 5 years. Some patients have continuing symptoms and remain on therapy, but more than 90% of all patients undergoing laparoscopic Nissen fundoplication remain satisfied with their decision to have surgery. These results are at least as good as those achieved with open fundoplication and prove the long-term worth of this procedure.


The American Journal of Medicine | 2003

Bowel dysfunction after laparoscopic antireflux surgery: incidence, severity, and clinical course

Alexander Klaus; Ronald A. Hinder; Kenneth R. DeVault; Sami R. Achem

PURPOSEnTo evaluate the incidence, severity, and clinical course of postoperative bowel dysfunction, primarily diarrhea, after laparoscopic antireflux surgery.nnnMETHODSnPatients who underwent laparoscopic antireflux surgery during January to December 1998 responded to a questionnaire about pre-existing and postoperative bowel symptoms, which included questions about the type of bowel dysfunction (diarrhea, abdominal pain, bloating, constipation), onset in relation to surgery, frequency, severity, duration, use of medical resources or diagnostic evaluations, and treatment outcome.nnnRESULTSnOf the 109 patients who underwent laparoscopic antireflux surgery at our center during the study, 84 (77%) completed the survey. Thirty-six (43%) had no bowel dysfunction before or after surgery, whereas 29 (35%) had pre-existing bowel dysfunction. New bowel symptoms developed postoperatively in 30 patients (36%), including bloating in 16 (19%) and diarrhea in 15 (18%). Two thirds of the patients with new diarrhea developed it within 6 weeks after surgery. The severity of the diarrhea ranged from mild to debilitating; 4 had fecal incontinence. Most patients (13/15) with diarrhea had symptoms for > or =2 years following surgery. No patient was hospitalized, and only 2 patients reported temporary work loss.nnnCONCLUSIONnPostoperative bowel dysfunction, namely diarrhea, is an important adverse effect of antireflux surgery. Awareness of this complication should lead to prompt recognition, effective management, and reduction in anxiety.


Seminars in Laparoscopic Surgery | 2001

Congenital diaphragmatic hernia in adults.

James M. Swain; Alexander Klaus; Sami R. Achem; Ronald A. Hinder

Congenital diaphragmatic hernia is rarely seen in adults. A review of the literature is presented, and 2 additional cases of Morgagni and Bochdalek hernias are presented. They were both repaired with the laparoscopic approach. Copyright


Mayo Clinic Proceedings | 2001

Rationale for Surgical Therapy of Barrett Esophagus

Tanja Bammer; Ronald A. Hinder; Alexander Klaus; Victor F. Trastek; Sami R. Achem

Barrett esophagus has malignant potential and seems to be an acquired abnormality. It is associated with chronic gastroesophageal reflux disease and represents its severest form. The literature comparing medical treatment with antireflux surgery was reviewed. Questions regarding the advantages of surgery, who should undergo surgery, whether surgery can change the course of Barrett esophagus, the change in cancer risk, who needs surveillance, and cost-effectiveness were addressed. The incidence of developing Barrett cancer was 1 in 145 patient-years in reviewing 2032 patient-years of medical therapy compared with 1 in 294 patient-years in reviewing 4122 patient-years after surgery. Median follow-up time in the 2 groups was 2.7 years in the medically treated patients and 4.0 years in the surgically treated patients. Surveillance of Barrett esophagus is required irrespective of treatment. Laparoscopic antireflux surgery was found to be cost-effective after 7 years. Although these data do not prove that surgery is superior to medical treatment in the prevention of cancer related to Barrett esophagus, we found a tendency for surgery to be better than medical therapy to prevent the development and progression of Barrett carcinoma.


Digestive Diseases and Sciences | 2007

Use of Acid Suppressive Medications After Laparoscopic Antireflux Surgery: Prevalence and Clinical Indications

Hugo Bonatti; Tanja Bammer; Sami R. Achem; Frank Lukens; Kenneth R. DeVault; Alexander Klaus; Ronald A. Hinder

Laparoscopic antireflux surgery (LARS) provides effective control of gastroesophageal reflux (GER) in more than 90% of patients. Despite this high success rate, some patients continue to consume acid suppressive medications after surgical intervention. In this study we evaluate the prevalence, clinical indications, and cause of use of acid reducing drugs in patients after LARS. Consecutive patients undergoing LARS for GERD were surveyed 2–3 years after surgery regarding use of acid suppressive medications, surgical outcome, and GERD specific symptoms. During the study period, 119 patients underwent LARS at our center. Ninety-eight (82%) were available for interview. Two patients died of unrelated causes and two declined to be interviewed. The remaining 94 individuals are the subject of this report. Ninety-four percent were satisfied with the outcome of surgery. Despite this high satisfaction rate, 37 of 94 (39%) were on antireflux medication (ARM; 62% proton pump inhibitors, 22% H2-receptor antagonists, and 16% others), with 70% using continuous medication. Of these patients, 54% took ARM after surgery for GERD-related symptoms, 95% of these patients responded to medical therapy, and yet again, 85% remained satisfied with the surgical outcome. Forty-six percent of patients on ARM after surgery had no GERD symptoms and took ARM for nonappropriate indications such as bloating. Only 47% of these responded to ARM; 82% of this group was satisfied with the surgical outcome. In conclusion, the use of ARM after LARS is a common occurrence despite a high satisfaction rate with this operation. Nearly half of patients consuming ARS after LARS are taking these medications for symptoms not necessarily related to GER. These findings underscore the importance of patient education in the use of these agents.


Obesity Surgery | 2004

Ventral Hernia Repair in Bariatric Surgery

Hugo Bonatti; Elisabeth Hoeller; W Kirchmayr; G Muhlmann; Matthias Zitt; Felix Aigner; Helmut Weiss; Alexander Klaus

Background: Obesity is an important risk factor for perioperative complications including the development of ventral hernias. Methods: This retrospective study comprises patients who underwent abdominal hernia repair simultaneously with or following implantation of a Swedish Adjustable Gastric Band® (SAGB). Results: 9 out of 415 patients (2.2%) who received a SAGB between January 1996 and June 2001 underwent ventral hernia repair. In 6 patients, hernias preexisted from previous abdominal surgery at the time of the bariatric procedure, and another 3 hernias occurred at the median and left upper abdominal trocar position following SAGB placement. Median BMI at time of SAGB implantation was 44 (range 35-52), and at time of hernia repair was 36 (range 25-46). 2 hernias were repaired during SAGB placement, 3 during redo surgery, and 2 during abdominoplasty. In 2 patients, significant weight loss with loss of soft tissue support of the hernia sac led to recurrent episodes of small bowel obstruction necessitating emergency repair. Repair included direct defect closure in 7 patients and sublay polypropylene net implantation in 2 patients. Recoveries have been uneventful without wound infections or recurrence in all patients after a median follow-up of 34 months (range 13-69). Conclusion: In morbidly obese patients, the optimal management and timing of incisional hernia repair should weigh the risk of recurrence and perioperative complications against the risk of hernia-associated complications.


The American Journal of Medicine | 2001

Laparoscopic antireflux surgery for supraesophageal complications of gastroesophageal reflux disease

Alexander Klaus; James M. Swain; Ronald A. Hinder

Gastroesophageal reflux disease can result in such supraesophageal complications as hoarseness, sore throat, cough, bronchitis, asthma, recurrent pneumonia, intermittent choking, chest pain, and ear pain. Appropriate patient care involves careful evaluation to decide on medical or surgical therapy. Preoperative testing must include endoscopy, 24-hour esophageal pH monitoring, and esophageal manometry. Additional evaluations, such as barium swallow, chest x-ray, bronchoscopy, and sinus radiographs, may be required. Medical treatment improves gastroesophageal reflux and supraesophageal symptoms. However, surgical therapy seems to provide better long-term results. A profile that predicts the best response to medical therapy has not been identified, although the best results with surgery are achieved in patients with nocturnal asthma, onset of reflux before pulmonary symptoms, laryngeal inflammation, and a good response to medical treatment.


Obesity Surgery | 2004

Adjustable Gastric Banding: Assessment of Safety and Efficacy of Bolus-Filling during Follow-Up

Werner Kirchmayr; Alexander Klaus; Gilbert Mühlmann; Reinhard Mittermair; Hugo Bonatti; Felix Aigner; Helmut Weiss

Background: Individual band-filling on demand of the morbidly obese patient is a major advantage of adjustable gastric banding. An increasing number of patients results in an enormous amount of outpatient follow-up visits, which inspired us to compare a stepwise band-filling strategy with a single bolus injection 4 weeks after the operative procedure. Methods: 40 consecutive patients were prospectively randomized in 2 groups. 20 patients (Group A) had stepwise band-filling during 6 monthly ambulant visits. 20 patients (Group B) had a bolus-filling 4 weeks postoperatively and had the next follow-up after another 5 months. Weight loss, complications and procedural costs during follow-up were compared. Results: Patients of both groups did not differ in age, gender or preoperative BMI.There was no significant difference postoperatively in excess weight lost (EWL) after 9 months. Postoperative complications did not differ significantly.By means of bolus-filling, a 60% and 53% reduction in outpatient clinical work was achieved within the 6 and 9 months, respectively. Conclusion: Postoperative management after gastric banding takes advantage of a single bolus-filling during the first postoperative 6 months due to sufficient weight loss, low complication rate but significant reduction of personal, financial and logistic efforts.


American Journal of Surgery | 2001

A new biliodigestive anastomosis technique to prevent reflux and stasis

Alexander Klaus; Helmut Weiss; Alfons Kreczy; Angelika Eigentler; Claudia Neher; Raimund Margreiter; Heinz Pernthaler

BACKGROUNDnThe Roux-en-Y procedure for biliodigestive drainage is most widely accepted, but 10% to 15% of patients postoperatively suffer from a blind-loop syndrome or cholangitis due to motility disorders. A new biliodigestive technique is evaluated in a rat model to prevent these complications.nnnMETHODSnThis experimental study in Wistar rats compares the Roux-en-Y technique with a new biliodigestive anastomosis creating a jejunal loop with luminal occlusion. Clinical parameters, small bowel motility, bacteriologic growth, and liver histopathology were evaluated in native and postoperative animals within a study period of 180 days.nnnRESULTSnBoth operative procedures were well tolerated. After 6 months intense fibrosis of the liver and high-grade purulent cholangitis were observed in animals in the Roux-en-Y group. In these animals enterobacter and enterococci overgrowth was found. Myoelectric small bowel recordings revealed significant impairment of slow-wave frequency, aboral velocity, and action potentials (percentage of phase III) in Roux-en-Y animals.nnnCONCLUSIONSnMotility disorders after conventional Roux-en-Y biliodigestive anastomosis are pivotal for histomorphological damage and infectious findings and can be prevented by using the new technique to create a jejunal loop with luminal occlusion.


Digestive Diseases | 2000

Manometric components of the lower esophageal double hump.

Alexander Klaus; Frank Raiser; James Swain; Ronald A. Hinder

Background/Aims: The lower esophageal sphincter manometry of patients with hiatal hernia often displays a double hump configuration. It seems that this is due to gastric herniation above the high-pressure zone of the crura. This study examines this manometric phenomenon in patients with hiatal hernia and relates it to the lower esophageal antireflux barrier. Methods: Manometric and 24-hour pH studies of 68 consecutive patients with suspected gastroesophageal reflux disease were analyzed to obtain information regarding the double hump and acid reflux. Results: The findings of a manometric double hump correlated well with the presence of a hiatal hernia of >5 cm. The overall length of the sphincter complex was greater in patients with a double hump, but the length below the respiratory inversion point was constant. Resting pressures at the respiratory inversion point were significantly lower than those measured at either high-pressure zone. The location of the respiratory inversion point was seen most commonly at the superior margin of the distal high-pressure zone. Double hump patients with a negative acid reflux score were found to have higher pressures in the distal high-pressure zone than those patients with acid reflux. Conclusions: The two high-pressure zones comprising the manometric double hump represent the crural and muscular components of the lower esophageal sphincter. Descriptive information regarding the double hump phenomenon is given, and the importance of the crural component of the lower esophageal sphincter in preventing acid reflux is stressed.

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Helmut Weiss

University of Innsbruck

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