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H Lippert

Publications and source records attributed to H Lippert.

At least 37 records · Page 2Linked to original sources
PubMed2002

[Significance of prospective multicenter observational studies for gaining knowledge in surgery].

The meta-analysis of randomised controlled studies (RCS) achieves the highest degree of reliability. Although the status of prospective multicenter clinical trials (PMS) is the subject of controversial discussion, recent publications suggest that these two forms of analysis reveal comparable results. On the other hand, particularly in the operative part of medicine, the problem of recruitment and performing of controlled studies for the more rapid evaluation of new surgical procedures becomes more evident. We followed these two aspects by using a separate analysis of data and biostatistical models. In the evaluation of single aspects, under no circumstances can non-controlled clinical trials replace randomised clinical studies in surgery. Only the use of a variety of forms of analysis in clinical research will lead to the desired scientific findings.

Data Interpretation, Statistical↗
PubMed2002

[Experiences with ambulatory arteriovenous shunt surgery. A cost-benefit analysis].

Placement of arteriovenous (av) fistulas has been executed at the reporting surgical department for 3 years. Calculation of the reimbursement by the insurance companies is based on the so-called "Unique Evaluation Table" (Einheitlicher Bewertungsmassstab). The aim of the study was to evaluate the efficiency of the placement of av fistulas in an out-patient setting and the acceptance of this approach in the patients. The costs based on an average of the duration of the intervention and treatment at the out-patient clinic per time unit for surgeon, nurse and operating room, as well as costs for use of specific materials were listed, summarized, and compared with the amount of money which was reimbursed by the insurance companies according to the "Unique Evaluation Table". During the 3-year time period, 67 patients underwent 70 placements of av fistulas in an out-patient setting (in total, 532 interventions). Patients answered a questionnaire, and procedures were evaluated for average costs. Based on the table-dependent reimbursement of DM 274.00 (according to the "Unique Evaluation Table"), costs of DM 497.94 (DM 445.50 for 54 min of mean duration of surgical procedure plus DM 52.44 for materials) were determined, indicating that no full reimbursement was found despite the fact that there was only a minimal rate of early complications (thrombosis, n = 2 [3%]) (infection, n = 1 [1.5%]). The expenses were 81.7% on average above the level of the reimbursement. In conclusion, despite high acceptance of an out-patient setting for placement of av fistulas in patients (82%), it is not efficient from an economic point of view and can be only provided for specifically selected cases. Therefore, it is not advisable at present to place av fistulas at German out-patient clinics with no following admission of the patients, to avoid financial disadvantages for the surgical department. New negotiations between the medical profession and the insurance companies are urgently needed to ensure an improved financial outcome for the clinics.

Ambulatory Surgical Procedures↗
PubMed2002

[Gastric pacing. A new method in obesity surgery].

Obesity is a severe health problem in Europe and in the USA. There are many different methods to reduce patients' weight. We report a new method: gastric pacing. Gastric pacing is intended to induce early satiety through electrical stimulation of the gastric wall. We report the operative technique and the complications.

Adult↗
PubMed2002

[Open vs. laparoscopic appendectomy].

This article discusses the question of whether open or laparoscopic appendectomy is preferable in today's clinical routine. The article is based on data from randomized studies, evaluation of meta-analyses, and data from nonrandomized, multicentric studies evaluating the treatment of appendicitis in routine clinical practice. According to the data analysis, open appendectomy (OA) offers advantages with regard to a significantly shorter operative time and lower hospital costs. Laparoscopic appendectomy (LA) is characterized by a significantly decreased rate of failed septic wound healing and faster recovery. Both procedures can be performed with the same degree of safety and comparable outcome for acute appendicitis. Laparoscopic appendectomy offers significant advantages for establishing a precise diagnosis in young fertile women and overweight patients suffering from lower abdominal pain. The currently available data do not provide precise guidelines for the treatment of perforating appendicitis. However, we found significant evidence indicating an increased rate of postoperative intra-abdominal abscess after laparoscopic appendectomy. Thus, a laparoscopic approach cannot be regarded as a standard technique in advanced appendicitis.

Abdominal Abscess↗
PubMed2002

Routine use of transrectal ultrasound in rectal carcinoma: results of a prospective multicenter study.

BACKGROUND AND STUDY AIMS: Preoperative transrectal ultrasound (TRUS) can establish the depth of penetration of a tumor, and thus provide important information for decisions about further management. In the literature, this method is reported to have a high level of sensitivity and specificity. Our investigation aimed at establishing the quality of the diagnostic procedure and treatment of colorectal carcinoma. PATIENTS AND METHODS: This investigation, which covered a 1-year period, and involved 75 hospitals, was conducted in the form of a prospective multicenter study and included a total of 3756 patients. For rectal carcinomas, all endosonographically determined uT categories were compared with histologically established T categories (pT). RESULTS: At 49 hospitals a total of 499 TRUS examinations in 1463 rectal carcinomas (34.1 %) were performed. A comparison of uT with pT category was possible for 422 TRUS examinations. Agreement between the preoperative endosonographic diagnosis with the histological diagnosis was found in 63.3 % (n = 267) of cases (95 % confidence interval 58.5 % - 67.9 %). The diagnostic accuracy was 50.8 % for pT1 carcinomas, 58.3 % for pT2 lesions, 73.5 % for pT3 tumors, and 44.4 % for pT4 carcinomas. Overstaging was observed in 23.9 %, overall, and understaging in 12.8 %. Understaging was significantly less common than overstaging (P < 0.05, s.). CONCLUSION: The accuracy of transrectal ultrasound used as a routine clinical examination in rectal carcinoma patients was clearly lower than that reported in the literature. We conclude that TRUS may aid decisions relevant to treatment only when used by well-trained investigators with a large case load of rectal carcinoma patients. Centralization of transrectal ultrasonography service is mandatory if a high level of quality is to be achieved with this method.

Carcinoma↗
PubMed2002

[Appendicitis in the last decade of the 20th century--Analysis of two prospective multicenter clinical observational studies].

AIMS OF THE STUDY: The authors present an accurate and comprehensive snapshot of appendicitis in the last decade of the 20 (th) century. The present study also aims to determine the influence of introduction of laparoscopic techniques on the quality of appendicitis therapy. PATIENTS AND METHODS: All consecutive patients admitted for suspected appendicitis were recruited into this prospective multicenter study. Two different periods of time were considered: from 1. 7. 1988 to 31. 12. 1989, 6 266 patients from 18 hospitals were included, and from 1. 6. 1996 to 31. 5. 1997, 7 398 patients from 34 institutions. RESULTS: In the first period (1988/89), 1 869 patients were treated conservatively (29.8 %), 4 397 (70.2 %) were operated. Histopathological analysis of the appendix documented no acute inflammation in 28.8 %, the perforation rate was 8.3 % and the wound infection rate 9.6 %. In the second period (1996/97), 2 430 patients were treated conservatively (32.8 %), in 24.9 % of all operated cases, the histopathological examination shows no acute inflammation of the appendix, the perforation rate was 5.9 % and the rate of wound infections 2.5 %. During this second period, 33.2 % of all appendectomies were performed using the laparoscope, the conversion rate was 7.2 %. CONCLUSIONS: The introduction of laparoscopic techniques did not modify the operative indications for treatment of appendicitis. An increase in the number of normal appendices removed was not observed. The number of perforations and the incidence of wound infections was significantly reduced in the second period.

Adolescent↗
PubMed2002

[Prospective multi-center study colon/rectum carcinoma (primary tumors)--Results of the year 2000].

INTRODUCTION: Surgical quality control in the form of multicentre studies make it possible to analyse the treatment status of a given surgical illness under quality assurance aspects. MATERIAL/METHODS: On 1. 1. 2000, under the patronage of the Convent of Hospital Chief Surgeons a project (ongoing) - organised and conducted by the Institute for Quality Management in Operative Medicine at the Otto-von-Guericke University of Magdeburg - was initiated to document and collect the data of patients with colorectal cancer throughout the whole of Germany. This work is supported by the German Society of Surgery, and the Surgical Working Group, Quality Assurance within the German Society of Surgery. Currently, some 282 hospitals throughout the country are involved in establishing a prospective documentation of colorectal carcinoma. Participation in this study is on a voluntary basis. The anonymity of both patients and hospitals is guaranteed, and no hospitals wishing to participate are excluded. Both operatively and conservatively treated patients are being documented, and no randomization takes place. RESULTS: In the year 2000, the participating hospitals documented a total of 9 477 patients with a colorectal carcinoma, including 6 975 patients with a carcinoma of the colon, and 3 402 with a rectal carcinoma. The average age of the patients was 68.5 years, and there were 5 010 men and 4 467 women. The operation rate was 99.2 %, the resection rate 95.6 %. The abdominoperineal resection rate was 27.4 %. The indicators for diagnostic quality as set out by Hermanek were largely complied with, but some deviations were noted. DISCUSSION: On the basis of the data collected, structures were established for a uniform Germany-wide quality management for a clinical condition with a major health policy impact. This information make it possible for the hospitals to identify and eliminate deficits in the structural and process quality in the diagnosis and treatment of colorectal cancer, and in this way to improve outcome quality. This means that the results of medical care research have an immediate impact on the individual treatment received by a given patient.

Adult↗
PubMed2002

[Pneumoperitoneum as occasional finding in chronic dialysis patients--laparotomy or conservative non-operative approach?].

Free air of unknown origin within the abdominal cavity is a serious problem, which in the majority of cases indicates the perforation of a hollow organ. In two cases, we report on i) detection of free air subdiaphragmatically by coincidence during follow-up investigation of an interstitial pulmonary disease (chest X-ray) in a 67-year old patient with chronic renal insufficiency, and ii) diagnostic of pneumoperitoneum (3 times as primary diagnosis) in a 63-year old multimorbid female (with chronic renal insufficiency) with recurrent, but unspecific epigastric symptoms over a time period of 5 years. The following investigations such as endoscopy, contrast enema, and abdominal ultrasound did not detect a perforation as most likely cause. The first patient was discharged after clinical observation, laboratory and ultrasound follow-up for 5 days. In the second case, neither explorative laparoscopy during the second clinical observation period nor laparotomy for required cholecystectomy because of cholecystitis could appropriately clarify the origin. In conclusion, the detection of a pneumoperitoneum in asymptomatic patients or subjects with unspecific abdominal symptoms requires always clinical monitoring and instrumental diagnostic, consisting of endoscopy in the upper gastrointestinal tract, contrast enema of the colon and abdominal and/or thoracal computed tomography, to definitely exclude perforation. In addition, ultrasound as third column detects early low amounts of fluid and is the suitable method for short-term follow-up. The cause of pneumoperitoneum, particularly in asymptomatic patients, can not be found in every case. Under these circumstances, non-operative treatment is favored.

Aged↗
PubMed2002

[Which factors are responsible for postoperative mortality in colorectal cancer patients?].

INTRODUCTION: The postoperative decease is the most severe complication in surgery. PATIENTS AND METHOD: Within the framework of a multicentre study between January 1 (st) and December 31, 1999, 3,756 patients, 1,463 of them suffering from rectal cancer and 2 293 from colon carcinoma, from 75 clinics were documented with the help of a standardized questionnaire. We compared data of 211 patients who died postoperatively with data of 3,484 patients who survived after surgical treatment of colorectal cancer. Logistical regressions, under inclusion and exclusion of intra- and postoperative complications, show independent influence factors on the postoperative decease and provide models for the prediction of the postoperative death. RESULTS: Compared to the patients who survived, the postoperative deceased patients were significantly older. They had a poorer risk profile and therefore a higher ASA-score (p < 0.001). 20.4 % of the patients underwent an emergency operation. General and specific postoperative complications occurred significantly more frequently. The model of a logistical regression allowed the prediction of postoperative decease with a sensitivity and specificity of 91 %. General postoperative complications such as pulmonary embolism (relative risk: 30.3), cardiac (relative risk: 24.1), renal (relative risk: 22.1), and pulmonary complications (relative risk: 12.0) are crucial for lethality. DISCUSSION: The postoperative decease is influenced by several factors. It is impossible to reduce the number of influence factors for the prediction of outcome. The general postoperative complications, however, represent a crucial problem. It is important to avoid these problems in order to reduce postoperative lethality.

Adolescent↗
PubMed2002

[Laparoscopic adrenalectomy--experiences with transperitoneal approach].

INTRODUCTION: We report our results of laparoscopic anterior transperitoneal adrenalectomy. PATIENTS: Between 4/1996 to 05/2001, a laparoscopic adrenalectomy was performed in 34 patients (median age 48 years). The adrenalectomy was performed transperitoneally (31 unilateral; 3 bilateral). The adrenaline level was measured in 7 patients with a pheochromocytoma. RESULTS: All tumors (mean size 3.5 cm; 0.4 to 8.0 cm) could be extirpated by laparoscopy. 9 pheochromocytomas; 9 cortisol producing tumors (one patient with a Carney's syndrome); 7 Conn's adenomas and 9 incidentalomas constituted these tumors. In the first third of the observation period, the surgery lasted 176 (95-270) minutes, in the last third 82 (50-130) minutes (p < 0,01). We postoperatively observed the following complications: one abdominal wall hematoma at a port-site and one edematous pancreatitis after alteration of the pancreatic tail. The adrenaline level continually rose from the beginning of surgery to the ligature of the suprarenal vein. CONCLUSION: Transperitoneal adrenalectomy in benign tumors (< 8 cm) is our method of choice. The resulting learning curve allowed the performance of adrenalectomy within an acceptable operative time and without significant blood loss. The transperitoneal technique is safe and well reproducible. The cosmetical results are convincing. We recommend an early ligature of the suprarenal vein in a pheochromocytoma.

Adrenal Gland Neoplasms↗
PubMed2002

[Fistula Banding - Success-promoting Approach in Peripheral Steal Syndrome].

AIM: Evaluation of the diagnostic and therapeutic management of peripheral steal syndrome after placement of an autologous arteriovenous (av-) fistula and presentation of treatment results after its surgical correction. METHODS: During a time period from 1994 to 1999, 1 253 av-fistulas for hemodialysis were placed in our surgical department. Twenty-one patients (1.68 %) underwent service operations because of considerable lower perfusion of the hand. In 14 patients the av-fistula was ligated, whereas in 7 patients, a polytetrafluorethylene (PTFE) sleeve was implanted at the venous site for fistula "banding" to diminish blood flow. In addition to the clinical finding, pre-, intra- and postoperative blood flow rates were determined using Duplex ultrasonography. RESULTS: In patients showing flow rates of < 250 ml (carefully disclosed empiric value) ligation was chosen, whereas in cases with distinctly increased flow rates, banding of the arterialized vein was performed (authors' individually selected borderline flow). The extension of the banding was specified according to the intraoperatively determined flow rates. Recurrent steal syndrome was not observed over the entire postoperative observation period of 1-3 years. CONCLUSION: Arterial steal syndrome is a rare complication after placement of an av-fistula. In the majority of cases, surgical therapy is necessary. Pre- and intraoperative analysis of flow rates using Duplex ultrasonography may help to select the appropriate surgical approach and may, thus, determine the success rate of service operation.

Adult↗
PubMed2002

Immunomodulation by perioperative administration of n-3 fatty acids.

It has been increasingly reported that administration of n-3 fatty acids is beneficial in patients with inflammatory processes. This effect is most likely caused by different biological characteristics, including an immunomodulating effect of the products derived from n-3 fatty acids through eicosanoid metabolism. The aim of this study was to investigate the effect of perioperative administration of n-3 fatty acids on inflammatory and immune responses as well as on the postoperative course of patients with extended surgical interventions of the abdomen. In particular, the effect of n-3 fatty acids on interleukin-6 release and on granulocyte/monocyte function (HLA-DR expression) was studied. There was a downregulation of the inflammatory response, and, simultaneously, a smaller postoperative immune suppression in the n-3 fatty acid group. In addition, we observed shorter postoperative periods in the intensive care unit and on the regular medical wards as well as lower rates of severe infections. The results suggest that perioperative administration of n-3 fatty acids may have a favourable effect on outcome in patients with severe surgical interventions by lowering the magnitude of inflammatory response and by modulating the immune response.

Abdomen↗
PubMed2002

Prevention and treatment of peritoneal carcinomatosis in experimental investigations with CPT-11 and oxaliplatin.

Following surgical resection of colorectal carcinoma, local recurrence in the tumor bed or in the mesentery remains a frequently encountered problem. Currently there are no recognized standard therapy protocols for the prevention of local recurrence or the treatment of peritoneal carcinomatosis. The aim of our trial was to investigate whether CPT-11 and oxaliplatin could decrease i.p. tumor growth in a basic experimental animal model. Experiments were performed on three groups of animals plus controls. In the first group, the cytostatic agents were applied directly following tumor cell implantation into the peritoneal cavity. In the second group, early postoperative i.p. chemotherapy (days 5, 10 and 15 following surgery) was administered. In the third group, late i.p. chemotherapy (days 15, 20 and 25 after tumor cell transfer) was administered with the intention of reducing a manifest peritoneal carcinomatosis. The trial also set out to describe any side effects observed following i.p. administration. The results indicated that CPT-11 and oxaliplatin were highly effective in reducing i.p. tumor spread after direct i.p intraoperative application. Intraperitoneal administration of CPT-11 or oxaliplatin also decreased i.p. tumor growth after early i.p. chemotherapy. CPT-11 was a little more effective with lower side effects. However, it was clear that it was not possible to treat a manifest peritoneal carcinomatosis in this way.

Anesthesia↗
PubMed2002

The role of proteomics in the diagnosis and outcome prediction in colorectal cancer.

Colorectal cancer is the second most frequent cancer in Western countries. Exogenous factors play a major role in the aetiology of sporadic colorectal cancer representing about 90% of all cases, hereditary cancers accounting for about 10% of patients. Thus, in the large majority of cases, cell dysfunction in CRC results from multiple rather than single, gene interactions. Numerous cellular events and environmental influences modify gene expression or post-translational protein modifications. Changes like glycosylation of proteins and lipids which are a common feature in colorectal cancer and influence cancer cell behaviour, cannot be directly detected by genetic studies. Better than genomics studies, functional proteomics studies allow the investigation of environmental factors over time, allowing the monitoring of metabolic responses to various stimuli. However, proteomics studies also have several drawbacks: a) current tools only allow narrow-range analyses, b) identification of proteins of interest remains cumbersome, c) protein studies address multiple compounds of high complexity, d) large amount of proteins are necessary to allow analysis, e) protein research require specific tools, e.g. tagged antibodies, that first have to be developed. Some protein tests are already in application for CRC: a classical prognostic test in colorectal cancer is based on the detection and quantification of a single protein (CEA) in body fluids. Recently, a screening assay based on APC protein truncation test has also been proposed. However, studies linking large protein expression patterns with clinical outcome in colorectal cancer are still in their infancy. To be able to predict occurrence of disease, and treatment outcome, more studies on genotype-phenotype correlations are needed both in sporadic and in hereditary colorectal cancer.

Colorectal Neoplasms↗
PubMed2001

Reduced neutrophil sequestration in lung tissue after laparoscopic lavage in a rat peritonitis model.

Laparoscopy to treat abdominal infections is becoming more and more popular. The effects of the CO(2) pneumoperitoneum have not yet been completely clarified. In a rat peritonitis model, therefore, we investigated the influence of laparoscopic lavage in comparison with the conventional technique. A defined multibacterial fecal specimen was installed in the abdominal cavities of 80 rats. These animals were randomized to three groups: group 1 (n = 32), no intervention; group 2 (n = 24), conventional; group 3 (n = 24), laparoscopic lavage. At 1, 2, and 8 hours after the surgical intervention, animals were killed and autopsied. The main outcome measures were bacteremia, interleukin-6 (IL-6) in plasma and ascites, changes in the blood count, and myeloperoxidase (MPO) activity in lung, liver, kidney, and pancreas. Differences of bacteremia were not found. In the ascites a marked increase in IL-6 was observed after 8 hours, which was lower in the treatment groups than in the controls (p <0.025). MPO activity as a measure of the granulocytes present in the tissue showed significant changes only in lung tissue. Two hours after the surgical intervention, the MPO in the lung in the laparoscopy group was significantly lower than that in the controls and the laparotomy group. In conclusion, conventional and laparoscopic lavage reduce inflammation. In this model, laparoscopic lavage with a CO(2) pneumoperitoneum appeared to have no negative influence on the inflammatory reaction during the early postoperative phase. Reduced neutrophil sequestration in lung tissue following laparoscopic lavage reflects the lower level of trauma caused by laparoscopy.

Animals↗
PubMed2001

Discordance between K-ras mutations in bone marrow micrometastases and the primary tumor in colorectal cancer.

PURPOSE: To study bone marrow micrometastases from colorectal cancer patients for the presence of K-ras mutations and to compare their genotype with that of the corresponding primary tumor. PATIENTS AND METHODS: Bilateral iliac crest aspiration was performed in 51 patients undergoing surgery for colorectal cancer, and bone marrow micrometastases were detected by immunohistochemistry. The presence of K-ras mutations was determined by single-strand conformation polymorphism analysis on both primary tumors and paired bone marrow samples and was confirmed by sequencing. RESULTS: In six patients with primary tumor mutations, it was possible to amplify a mutated K-ras gene also from the bone marrow sample. In three of those patients the pattern of K-ras mutations differed between both samples, in two patients the mutation was identical between the bone marrow and its primary tumor, and in one patient the same mutation plus a different one were found. Fifteen of 17 K-ras mutations found in primary tumors were located in codon 12, whereas in bone marrow, five of seven mutations were found in codon 13 (P =.003). CONCLUSION: Our results demonstrate that, at least for K-ras mutations, disseminated epithelial cells are not always clonal with the primary tumor and they question the malignant genotype of bone marrow micrometastases. They also indicate that different tumoral clones may be circulating simultaneously or sequentially in the same patient. Analysis of the type of mutations suggests that cell dissemination might be an early event in colorectal carcinogenesis.

Aged↗