[A virtual reality simulator for objective assessment of surgeons' laparoscopic skill]. / Laparoskopiesimulator Abbildung der manuellen Geschicklichkeit in der laparoskopischen Chirurgie.

BACKGROUND: The aim of this study was to validate computed virtual reality simulation as a tool to assess laparoscopic skills and to establish whether the simulator allows differentiating between surgeons with different laparoscopic experience. METHODS: 27 physicians at the surgical department of the University of Marburg, Germany, with different experience in laparoscopic surgery were divided into three groups: experienced (group I), intermediate (group II), and novices (group III). Following a brief introduction to the virtual reality simulator (LapSim), each participant performed twice a training program consisting of seven tasks (examinations I and II). RESULTS: Comparison of experienced surgeons with less experienced laparoscopic physicians showed a significant (P<0.05) superiority of group I at examinations I and II in most exercises. The groups' difference was more obvious in examination II, since the technique was new for all participants during examination I. Tasks of low complexity in virtual reality such as camera navigation, which are performed by young, not yet responsible surgeons in real surgery, did not show significantly different results between the three groups. CONCLUSION: Differences in laparoscopic experience can be visualised with a virtual reality simulator, and thus a simulator is helpful for assessing surgeons' laparoscopic skills.

[Haemorrhoidectomy: conventional excision versus resection with the circular stapler. Prospective, randomized study]. / Hämorrhoidektomie: Konventionelle Exzision versus Resektion mit dem Klammernahtgerät. Prospektiv, randomisierte Studie.

BACKGROUND AND OBJECTIVE: The goal of this study was to compare two surgical methods of treating for haemorrhoids that aim at closure of the wound: resection with a circular stapler and a conventional, closed haemorrhoidectomy. PATIENTS AND METHODS: 80 patients (41 males, mean age 47,1 years) with haemorrhoids stage 3 were randomized and treated with stapler haemorrhoidectomy (test group; n = 40) or had an haemorrhoidectomy according to Fansler and Anderson (control group; n = 40). Following a standardized study protocol we compared postoperative results on the operating day and one week, six weeks, six months and one year afterwards uni- and multivariate analysis and we also calculated the costs. RESULTS: The stapler haemorrhoidectomy proved to be the method causing significantly reduced pain in the early postoperative period so that the patients needed less pain relief. They were able to return to work earlier. One year after stapler haemorrhoidectomy there were three episodes of postoperative bleedings that required intervention, one in the control group. Six patients still had haemorrhoids stage 3, six patients over the age of 65 had persistent anal incontinence (I degrees according to Parks) with proven sphincter dysfunction and disturbances in voiding their bowel with resulting deterioration of quality of life, significantly more frequent than in the control group. CONCLUSIONS: Stapler haemorrhoidectomy cures stage 3 haemorrhoids on a long term basis in 84.2 % of patients, costing less than all alternative treatments. In some cases, it can be associated with postoperative complications.

Second step: testing-outcome measurements.

Despite worldwide enthusiasm for endoscopic surgery, this new technology is now on the top of McKinlay's "product life circle curve." Critical questions are being asked about its benefits and burdens, but the concepts applied and the methodologies used for technology assessment are in a similar position as endoscopic surgery and need a critical evaluation. (1) There are incorrect and outdated concepts for the scientific basis of surgery (surgical theory) including the basic sciences involved; biomedicine still dominates, but assessment of outcome after operations is no longer possible without clinical epidemiology and social psychology. (2) Based on an outdated scientific theory for surgery, an outdated concept of disease is still propagated. It is denoted as mechanical and is based solely on biomedicine. Human subjects are reduced to biologic machines, and outcomes measurement excludes most dimensions of functioning and well-being. To achieve a valid result for outcome measures, a hermeneutic approach must be combined with the mechanical approach. (3) Based on an outdated model of disease, the outcomes used in endoscopic surgery rely too much on traditional measures, such as mortality rate, complication rate, hospital stay, and especially an endless list of biochemical mediators. Their alterations during the perioperative period have not yet been shown to be related to clinical or hermeneutic outcomes. A new method of assessment for clinical trials in endoscopic surgery and for other surgical problems is outlined, such as for surgical infections and for surgical oncology. It includes an index of recovery and objective health status assessed by the doctor, a quality-of-life self-report by the patient, and the true endpoint concept as a critical weighting of both types of outcome by patients and doctors.

[Clinical guidelines as part of total quality management. Analysis of heterogenous treatment concepts of sepsis in various clinics with computer assisted generation, logical testing and complexity assessment of clinical algorithms]. / Klinische Leitlinien als Teil eines umfassenden Qualitätsmanagements. Analyse heterogener Behandlungskonzepte der Sepsis verschiedener Kliniken mit Hilfe computerunterstützter Erstellung, logischer Uberprüfung und Komplexitätsbewertung klinischer Algorithmen.

Generation, local tailoring, implementation and evaluation of clinical guidelines is an integral part of quality management. Clinical guidelines are intimately related to the independency of physicians' decisions. By this the physicians should be responsible for guideline development and guarantee the use of adequate methods of total quality management and outcome assessment. Formal consensus finding and transparency of evidence are necessary to guarantee the use of guidelines. Clinical algorithms are highly formalized and they are well suited for generation and analysis by the software ALGO. Determination of complexity and comparison of the clinical contents of algorithms is done by the scores CASA (Clinical Algorithm Structural Analysis) and CAPA (Clinical Algorithm Patient Abstraction). In a study of 22 clinical departments on treatment management concepts in sepsis following anastomotic insufFiciency in colorectal carcinoma a considerable heterogeneity was shown using this program.

[What is the cost of laparoscopic cholecystectomy?]. / Was kostet die laparoskopische Cholecystektomie?

After laparoscopic cholecystectomy (LC) has replaced open cholecystectomy (OC) to a large extent as standard method in the operative treatment of cholecystolithiasis the question of costs and economics raises. To evaluate this question the data of 50 patients who underwent elective LC were analysed in a retrospective study and compared with the data of 50 patients who were cholecystectomized using the open technique. The median of in-hospital stay was 6 (3-15) days for LC and 10 (3-33) days for OC. The median of time of working-disability was 14 (2-35) days for LC and 21 (2-56) days for OC. Total cost (median) of 3788 (2637-8101) DM for LC compared to 4509 (2041-15218) DM for OC. The median of hospital income was 2790 (1395-6975) DM for the LC-group and 4650 (1395-15346) DM for the OC-group. Due to the shorter in-hospital stay of LC-patients this method causes a microeconomical loss for the hospital compared to OC. Macroeconomically LC represents a benefit because of shorter working-disability.

Elevated plasma histamine concentration as a sensitive real-time parameter for distinct phases of surgical trauma: a tool for technology assessment.

High technology plays an important role in surgery, either to expand surgical procedures or to reduce tissue trauma, which is a main goal of minimum invasive surgery. Due to the tremendous increase of costs the problem of technology assessment will not only be solved by statistical methods, but also by biomedical considerations and laboratory tests. Histamine release could be an indication for tissue trauma, which is caused directly by tissue damage or indirectly by infection or hypoxia. Therefore histamine release was investigated during different phases of operation in two clinically very important and complex situations: resection of liver metastases of colorectal carcinoma and resection of the oesophagus because of an oesophageal carcinoma. To model this situation in animal experiments, two randomized controlled studies were conducted in sheep. Traditional techniques were compared with techniques of minimum invasive surgery. Plasma histamine levels were determined at well-defined phases of the operation. Histamine release was demonstrated at distinct phases of operation indicating considerable specificity of this parameter, if sensitivity is guaranteed by advanced tests. Incision of the liver capsule by thermocauterization, liver ischaemia, tissue trauma in more extended disruption of perioesophageal tissue were causes of more extended histamine release. It is concluded that measurement of plasma histamine is a suitable indicator for discriminating between extended and minimum invasive surgery. The consequence of considering this parameter may be less complications in the post-operative period and a short hospital stay with better quality of life.

Human intestinal diamine oxidase (DAO) activity in Crohn's disease: a new marker for disease assessment?

The key-enzyme for the metabolism of diamines in man is diamine oxidase (DAO). Its highest activities are in the intestinal mucosa, localized in the cytoplasm of the mature enterocytes of the small and large bowel. If the gut is affected by inflammation in Crohn's disease macroscopical changes are observed. This prospective study investigated if these mucosal alterations are also reflected in changes of mucosal diamine oxidase activity and/or mucosal histamine content respectively. Twenty patients (12 female, 8 male; age: means = 31, range 18-49 years) undergoing gut resection because of complications in Crohn's disease (Jan.-Dec. 1988) formed the basis of the study. Tissue samples of the resected material from areas inflamed and histologically not involved in the disease were investigated for diamine oxidase activities and histamine content. Diamine oxidase activities in the mucosa obtained from the macroscopically normal proximal (155.6; (76-393) mU/g (means, range)) and distal (132; (58.5-295) mU/g) resection margins were similar to our previous findings. In all patients, however, samples from the diseased mucosa had significantly (ca. 50%) lower diamine oxidase activities (74.5; (5-262) mU/g) compared to the healthy tissue. Similar differences were found in material obtained either from whole intestinal wall or from the mucosa. The determination of diamine oxidase activity constitutes possibly a more unambiguous and earlier parameter for assessing the extent of the inflamed area than histological disease presentations. Using biopsies the necessary extent of resection could be estimated before operation: this may influence operative strategies and help in the definition of the minimum amount of inflamed gut to be removed.