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N Senninger

Publications and source records attributed to N Senninger.

At least 73 records · Page 4Linked to original sources
PubMed2000

[Does quantity mean quality? An analysis of 116,000 patients regarding the connection between the number of cases and the quality of results].

METHODS: Between 1993 and 1998 data of 27,000 patients with hip fractures and 89,000 patients undergoing cholecystectomy were collected by the department of external quality assurance at the chamber of physicians of Westphalia-Lippe. The data were analyzed for the relationship between volume and outcome, specified as mortality and morbidity. Logistic regression was used to adjust the results for demographic and clinical risk factors. RESULTS: The risk-adjusted probability of death from cholecystectomy was 89% higher in the group of small volume clinics (less than 30 procedures per year) than in the group of large volume clinics (more than 120 procedures per year) (odds ratio 1.89; 95% CI 1.19-3.00). Mortality from hip fractures was 33% higher (odds ratio 1.33, 95% CI 1.09-1.63) for the group of small volume clinics (less than 15 procedures per year) than the group of large volume clinics (more than 45 procedures per year). Among the group of small volume hospitals were some with excellent results, but they are more likely to be found in the group of large volume hospitals. On the other hand there were some departments with poorer results in the group of large hospitals. CONCLUSIONS: There is no threshold for good results. In general there is an inverse relationship between volume and outcome. High volume, though, is not a substitute for good results. It is not possible to infer good quality from high volume alone. Small-volume departments should document quality of care and results thoroughly.

Cholecystectomy↗
PubMed2000

Changes in intestinal transit time after proctocolectomy assessed by the lactulose breath test.

After proctocolectomy with ileal pouch-anal anastomosis (IPAA) patients have increased stool frequency and intermittently use antidiarrheal medication. In addition to other factors, gastrointestinal transit time (MTT) could influence stool frequency. The aim of this study was to investigate how MTT changes after IPAA and to study whether MTT has an influence on daily stool frequency. In a prospective trial MTT was investigated with the lactulose breath test in 12 patients undergoing surgery for chronic ulcerative colitis (CUC) or familial adenomatous polyposis coli (FAPC) at different stages: before proctocolectomy, after IPAA with loop ileostomy, and 3 months and 1 year after ileostomy closure. MTT was also measured in 12 patients with IPAA, 12 patients with subtotal colectomy and ileorectal anastomosis (IRA), and 8 patients with conventional proctocolectomy and Brooke ileostomy (CPC) several years after surgery. Twelve healthy volunteers served as controls. Before IPAA, MTT was prolonged in CUC versus FAPC and controls. After restoration of gut continuity MTT was markedly accelerated. After 1 year MTT was slowed again, though values before proctocolectomy and those in controls were not reached. Several years after surgery MTT was significantly prolonged in IPAA and IRA versus controls. In CPC, MTT could not be determined by lactulose breath test. Stool frequency showed an inverse correlation to MTT in IPAA. In conclusion, this study shows that orocecal and oropouch transit are accelerated in the early postoperative period after (procto)colectomy but prolonged in the long-term course. Adaptation of the small bowel takes longer than 1 year. Impairment of stool frequency may be partly due to this adaptation.

Adenomatous Polyposis Coli↗
PubMed2000

[Electronic documentation in medicine; flexible concepts versus isolated solutions].

Computer-based medical documentation so far proved advantageous especially through standardization of data entry and increased access speed. Additional benefits can be achieved through the implementation of integrated, cross-project documentation tools and their integration into the clinical work-flow, which allow data to be used for a wide variety of applications (e.g. quality management, clinical research, clinic management). The presence of incompatible documentation software often complicates the realization of these goals. Implementation of new documentation tools therefore should consider flexibility and multiple-use of data as primary design goals. In the presented paper requirements for flexible documentation tools are introduced. The Entity-Attribute-Value-Model is described as a possible means of implementation. Practical experiences made with a prototype application are reported.

Germany↗
PubMed2000

Long-term investigations after pyloromyotomy for infantile pyloric stenosis.

Between 1919 and 1941, 71 infants suffering from pyloric hypertrophy were operated on by Ramstedt performing an extramucosal pyloromyotomy. Of these patients, we could identify and investigate 41. Four out of 31 long-term surviving patients have been Billroth II-resected (BII). One of these needed re-resection because of an anastomotic ulcer. None of all the long-term survivors developed a carcinoma. Two patients were treated conservatively because of gastritis and one because of esophagitis. All patients, except the one requiring re-resection and one suffering from maldigestion, were absolutely free of complaints. The average time between operation and re-checking was 57 years. The oldest patient was examined 72 years after the operation.

Adolescent↗
PubMed2000

Telepathology network: conceptual groundwork and evaluation.

Telepathology uses telecommunication technology to transmit microscopic images for diagnostic or teaching purposes. Basic requirements for a telepathology system are described. Usage scenarios for a telepathology network are presented including applications in intraoperative frozen section diagnosis, scientific collaboration and computer based training. Results of an evaluation of 4 currently available telepathology systems are presented.

Computer Communication Networks↗
PubMed1999

[Foreign research position in the career development of academic surgeons].

Since there are no data concerning the results/efficiency of research stipends in foreign countries, the aim of this study was to analyze the experience of German surgeons doing research work abroad. Seventy-four fellows (residents) in surgical training who conducted research outside Germany between 1986 and 1995 were interviewed using a detailed questionnaire. Back in Germany, the results and experience gained from research abroad led in the majority of cases to a PhD degree ("habilitation"), a high number of publications, and intensified research efforts in the same field using the methods learned abroad. In Germany, better support for researchers in terms of better clinical and scientific perspectives is urgently needed according to numerous comments.

Adult↗
PubMed1999

Transepithelial transport processes at the intestinal mucosa in inflammatory bowel disease.

Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) of unknown etiology. Oral absorption studies have shown an increased intestinal permeability for various sugar molecules in patients with IBD and their healthy relatives as a possible pathogenetic factor. However, the various transport pathways through the mucosal barrier have not yet been examined. This study therefore investigated whether antigens pass the epithelial barrier by a transcellular or a paracellular pathway. Mucosa of freshly resected specimens from CD (n = 10) or UC (n = 10) patients was investigated by immunoelectron microscopy and compared with healthy mucosa. Epithelial transport was studied with the antigens ovalbumin and horseradish peroxidase after defined incubation. Labeling density of subunit c of ATP synthetase was determined in mitochondria of enterocytes of all specimens. In all specimens epithelial transport of OVA and HRP was principally transcellular through enterocytes with normal ultrastructure, although some tight junctions in CD and UC were dilated. Antigens were transported within vesicles to the basolateral membrane 2.5 min after incubation. The level of enterocytes with electron-lucent cytoplasm containing a high amount of antigens was higher in CD and UC than in healthy mucosa, depending on the grade of inflammation. ATP synthetase was significantly decreased in electron-lucent cytoplasm of CD and UC to normal ultrastructure of healthy mucosa. Our study shows that ovalbumin and horseradish peroxidase taken up by the apical membrane reach the paracellular space by vesicular transport in healthy and IBD enterocytes within a few minutes. Transcellular pathway is affected in both CD and UC, which is indicated by a high level of antigens within the cytosol. We speculate that increased intestinal permeability in IBD results substantially from enhanced transcellular transport.

Adult↗
PubMed1999

Effect of anti-CD11b (alphaM-MAC-1) and anti-CD54 (ICAM-1) monoclonal antibodies on indomethacin induced chronic ileitis in rats.

Leukocyte emigration from blood to sites of inflammation involves sequential interaction of specific adhesion molecules expressed by both leukocytes and endothelial cells. The central steps in leukocyte-endothelial adhesive interactions are leukocyte rolling, sticking, and transmigration. This study investigated the effect of monoclonal antibodies against CD54 (ICAM-1) and CD11b (alphaM-chain of MAC-1) on intestinal inflammation. Anti-CD54 and anti-CD11b were tested in rats with indomethacin-induced chronic ileitis. Macroscopic changes were assessed by a modified version of the Wallace et al. score. Leukocyte rolling and sticking were investigated by intravital microscopy. Results show that indomethacin administration led to a chronic inflammatory response characterized by significant increase (P<0.05) in rolling (from 5.41+/-2.87 to 32.41+/-15.03 100 microm(-1) s(-1)) and sticking (from 0.16+/-0.18 to 9.11+/-5.3 100 microm(-1) s(-1)) leukocytes. After antibody treatment only the anti-CD11b group showed significant (P<0.05) reduction in rolling (from 32.41+/-15.03 to 6.6+/-2.7 100 microm(-1) s-1) and sticking (from 9.11+/-5.3 to 0.07+/-0.09 100 microm(-1) s-1) leukocytes. This was also the case for macroscopic changes. Indomethacin led to a rise in the Wallace score from 0 to 4.29+/-0.76 points (P<0.05) and anti-CD11b to a reduction from 4.29+/-0.76 to 1.29+/-1.11 points (P<0.05). Anti-CD54 and combined anti-CD11b/CD54 administration was not followed by significant changes. Therefore we suggest that leukocyte-based CD11b but not endothelial-based CD54 contributes most to leukocyte adhesion in the setting of indomethacin-induced ileitis in rats.

Animals↗
PubMed1999

Preoperative staging of esophageal carcinoma: miniprobe sonography versus conventional endoscopic ultrasound in a prospective histopathologically verified study.

BACKGROUND AND STUDY AIMS: Endosonographic staging of esophageal carcinoma may be limited by non-traversable tumor stenoses. Dilation of malignant esophageal strictures carries a significant risk of esophageal perforation. We therefore evaluated the use of ultrasonic miniprobes in the staging of stenotic esophageal carcinoma compared with conventional endoscopic ultrasound. PATIENTS AND METHODS: In a blinded, prospective study, which included histopathological evaluation, 53 consecutive patients (43 male, 10 female, mean age 61 years) with stenosing esophageal carcinomas were examined preoperatively. Endosonography was done using the optical GF-UM3 echo endoscope. If tumor strictures were not traversable with this instrument, a blind esophagoprobe, the MH-908 was used for endosonography. Miniprobe sonography (MPS) was done during esophagoscopy in all patients. The various imaging modalities were assessed in terms of complete tumor traversability and correct tumor staging. Every patient underwent surgical tumor resection. RESULTS: MPS of the esophagus and proximal parts of the stomach was possible in all 53 patients without prior dilation of tumor stenoses. Endosonography with the GF-UM3 instrument was precluded in 23 patients (43.4%) while in 20 of the latter patients the MH 908 esophagoprobe could be passed through tumor stenoses. The overall accuracy rates for depth of tumor infiltration (T) staging were: 62% (31/50) for endosonography (GF-UM3 plus esophagoprobe) and 86.8% (46/53) for MPS. The accuracy rates for T staging in tumors traversable both with the GF-UM3 echo endoscope and with miniprobes were 56.7% (17/30) for GF-UM3 and 80% (24/30) for MPS. The accuracy rates for T staging in tumors traversable only with the MH-908 esophagoprobe and with miniprobes were 70% (14/20) for the MH-908 and 95% (19/20) for MPS. With regard to the presence or absence of peri-esophageal metastatic lymph nodes (N staging), the accuracy rates were 83% (25/30) for MPS and 70% (21/30) for the GF-UM3, and 80% (16/20) for MPS and 70% (14/20) for the MH-908. CONCLUSION: Compared with conventional endosonography using 7.5-MHz large diameter instruments, MPS enables: a) safe passage through high-grade malignant esophageal strictures, achieving b) higher accuracy rates for T staging, and c) similar rates for N staging. The use of MPS can also represent an improvement in the comfort and safety of patients. Moreover, miniprobe sonography is highly cost-effective compared with conventional endosonography. Thus, MPS appears to be a valuable addition to the armamentarium for staging esophageal carcinoma.

Adult↗
PubMed1999

Workflow analysis and evidence-based medicine: towards integration of knowledge-based functions in hospital information systems.

The large extent and complexity of scientific evidence described in the concept of evidence-based medicine often overwhelms clinicians who want to apply best external evidence. Hospital Information Systems usually do not provide knowledge-based functions to support context-sensitive linking to external information sources. Knowledge-based components need specific data, which must be entered manually and should be well adapted to clinical environment to be accepted by clinicians. This paper describes a workflow-based approach to understand and visualize clinical reality as a preliminary to designing software applications, and possible starting points for further software development.

Artificial Intelligence↗
PubMed1998

Decreased HER-2 tyrosine kinase expression in rectal mucosa of FAP patients following low-dose sulindac chemoprevention.

As a part of the mechanisms of action in reversing FAP adenomas by the low-dose sulindac maintenance therapy (2 x 25 mg/patient per day), the extent of HER-2 proto-oncogene expression in the rectal mucosa seems to be of interest. Immunocytochemical analyses were performed in plasma and in rectal tissue of sulindac-treated FAP patients during an 18 months follow-up and compared with rectal tissue of patients with FAP, Crohn's disease, or rectal cancer or with healthy volunteers. HER-2 was significantly reduced and maintained in tissue under sulindac chemoprevention below base line levels of healthy individuals, but not in plasma. Therefore, a direct or indirect effect of sulindac as a tyrosine kinase inhibitor may be implicated. During NSAID treatment HER-2 protein expression as a prognostic tool seems to be of little clinical relevance.

Adenomatous Polyposis Coli↗
PubMed1998

Effect of surgeon expertise on the outcome in primary hyperparathyroidism.

BACKGROUND: Success in surgery for primary hyperparathyroidism (PHPT) is thought to be closely linked to surgical expertise. We investigated the effect of the surgeon's experience on the postoperative outcome in patients with PHPT. DESIGN: Cohort study with retrospective analysis. SETTING: University tertiary care center. PATIENTS: Two hundred thirty consecutive patients with PHPT. We excluded patients with prior cervical surgery, parathyroid carcinoma, multiple endocrine neoplasia types 1 and 2, and renal hyperparathyroidism. INTERVENTIONS: All 230 patients underwent bilateral neck exploration for PHPT. MAIN OUTCOME MEASURES: We registered complication rates, fulfillment of predefined operative concepts, and operative time in 230 cervical revisions for PHPT and compared the results of experienced surgeons (40 or more cervical revisions for PHPT performed before 1988) with those of surgeons still in training. RESULTS: Two surgeons classified as experienced operated on 75 patients. Under supervision of these surgeons, most operative procedures (n=155) were performed by 12 different surgeons classified as less experienced. Complications were observed in 31 patients (13.5%) with no statistical difference between the specialists and the less-experienced surgeons (P=.85). The ability to demonstrate 4 or more parathyroid glands was significantly increased for the specialists (74.7% vs 51.6%; P<.001), who also terminated the operation earlier (average, 15 minutes; P<.001). CONCLUSION: In an analysis of 230 operations for PHPT in patients without prior neck surgery, no effect of the surgeon's experience on postoperative outcome was demonstrated. Under the supervision of experienced endocrine surgeons, less-experienced surgeons perform cervical revisions for PHPT with comparable results, although with longer operating time.

Adolescent↗
PubMed1998

[Open pelvic fracture--an indication for laparotomy?].

Open pelvic fractures are rare and account for 1-5% of all pelvic fractures. Mortality rates of 50% and even more have been reported. Bleeding and septic complications are the major causes of death. In our retrospective study from 1974 to 1996 the data of 40 patients were analyzed. Five patients died (12.5%); 28 survivors could be investigated with a mean follow-up of 10 years. It is concluded that the comparably low mortality rate is due to a standardized treatment protocol. The main principles of management are emergency stabilization of the unstable pelvis and early laparotomy.

Adolescent↗
PubMed1998

[Clinical anatomy as an integrating element in teaching surgical subjects].

Different conceptions to revise the licensing regulations for physicians (Approbationsordnung für Arzte) aim to interlock preclinical and clinical subjects. Therefore a more practice-oriented anatomy has to be taught in basic and postgraduate medical education. At the Westfalian Wilhelms University of Münster we established an interdisciplinary anatomical education, executed by clinical lecturers in cooperation with the educational staff of the Department of Anatomy. The intergral element is the comprehensive constitution of clinical anatomy: clinical practitioners of different specialties together with anatomists give lessons in applied anatomy accompanying the dissection course. Clinically experienced lecturers of anatomy guide senior medical students in practical courses, refreshing their anatomical knowledge using particular prosections. These courses correlate with the topics of the distinct clinical tutorials. Conjointly clinical practitioners and anatomists plan, and perform meetings in postgraduate medical education.

Anatomy↗