Comparison of Venae Sectio vs. modified Seldinger Technique for Totally Implantable Access Ports; Portas-trial [ISRCTN:52368201]

BACKGROUND: The insertion of a Totally Implantable Access Port (TIAP) is a routinely employed technique in patients who need a safe and permanent venous access. The number of TIAP implantations is increasing constantly mainly due to advanced treatment options for malignant diseases. Therefore it is important to identify the implantation technique which has the optimal benefit/risk ratio for the patient. STUDY DESIGN: A single-centre, randomized, controlled superiority trial to compare two different TIAP implantation techniques. Sample size: 160 patients will be included and randomized intra-operatively. Eligibility criteria: Age equal or older than 18 years, patients scheduled for primary elective implantation of a TIAP in local anaesthesia and a signed informed consent. Primary endpoint: Primary success rate of the randomized technique. Intervention: Venae Sectio in combination with the Seldinger Technique (guide wire and a peel away sheath) will be used to place a TIAP. Reference treatment: Conventional Venae Sectio will be used with a direct insertion of the TIAP without guide wire or peel away sheath. Duration of study: Approximately 20 months. ORGANISATION/RESPONSIBILITY: The trial will be conducted in compliance with the protocol and in accordance with the moral, ethical, and scientific principles governing clinical research as set out in the Declaration of Helsinki (1989) and Good Clinical Practice (GCP). The trial will also be carried out in keeping with local and regulatory requirements. The Klinisches Studienzentrum Chirurgie (KSC) – Centre of Clinical Trials in Surgery at the Department of Surgery, University Hospital Heidelberg is responsible for planning and conduction of the trial. Documentation of patient's data will be accomplished via electronical Case Report Files (eCRF) with MACRO(®)-Software by the KSC. Randomization, data management, monitoring and biometry are provided by the independent Koordinierungszentrum für Klinische Studien (KKS) – Coordination Centre for Clinical Trails at the University of Heidelberg

The role of adjuvant chemotherapy for patients with resected pancreatic cancer: Systematic review of randomized controlled trials and meta-analysis

Background: In patients undergoing surgery for resectable pancreatic cancer prognosis still remains poor. The role of adjuvant treatment strategies (including chemotherapy and chemoradiotherapy) following resection of pancreatic cancer remains controversial. Methods: A Medline-based literature search was undertaken to identify randomized controlled trials that evaluated adjuvant chemotherapy after complete macroscopic resection for cancer of the exocrine pancreas. Five trials of adjuvant chemotherapy were eligible and critically reviewed for this article. A meta-analysis (based on published data) was performed with survival (median survival time and 5-year survival rate) being the primary endpoint. Results: For the meta-analysis, 482 patients were allocated to the chemotherapy group and 469 patients to the control group. The meta-analysis estimate for prolongation of median survival time for patients in the chemotherapy group was 3 months (95% CI 0.3-5.7 months, p = 0.03). The difference in 5-year survival rate was estimated with 3.1% between the chemotherapy and the control group (95% CI -4.6 to 10.8%, p > 10.05). Conclusion: Currently available data from randomized trials indicate that adjuvant chemotherapy after resection of pancreatic cancer may substantially prolong disease-free survival and cause a moderate increase in overall survival. In the current meta-analysis, a significant survival benefit was only seen with regard to median survival, but not for the 5-year survival rate. The optimal chemotherapy regimen in the adjuvant setting as well as individualized treatment strategies (also including modern chemoradiotherapy regimens) still remain to be defined. Copyright (C) 2008 S. Karger AG, Basel

A concept for trial institutions focussing on randomised controlled trials in surgery

<p>Abstract</p> <p>Background</p> <p>Although considered the reference standard for generating valid scientific evidence of a treatment's benefits and harms, the number of Randomised Controlled Trials (RCT) comparing surgical techniques remains low. Much effort has been made in order to overcome methodological issues and improve quality of RCTs in surgery. To the present there has been, however, only little emphasis on development and maintenance of institutions for implementation of adequately designed and conducted surgical RCTs.</p> <p>Mehods/Design</p> <p>Description of the developments in surgical RCT infrastructure in Germany between 2001 and 2006. Cross sectional evaluation of completed and ongoing surgical RCTs within the German Surgical Society and the Clinical Study Centre, Department of Surgery, University of Heidelberg.</p> <p>Results</p> <p>Foundation of a national Clinical Trial Centre (CTC) for the organisation of multi-centre RCTs in the surgical setting (Study Center of the German Surgical Society, SDGC). Establishment of a network of CTCs with affiliated Clinical Sites (CSs) to enhance patient recruitment and shorten the duration of RCTs. Since its foundation four surgical RCTs with a total sample size of 1650 patients (1006 of these randomised) have been supervised by the SDGC with 35 CSs involved in patient recruitment. Five further CTCs were set up in 2006. Together with their affiliated CSs a network has been organised providing improved conditions for the conduction of surgical RCTs.</p> <p>Conclusion</p> <p>Improvement of infrastructure substantially facilitates integration of RCTs into routine surgical practice. A network of collaborating CTCs and CSs can provide an adequate infrastructure for the conduction of multi-centre RCTs.</p

Protocol design and current status of CLIVIT: a randomized controlled multicenter relevance trial comparing clips versus ligatures in thyroid surgery

BACKGROUND: Annually, more than 90000 surgical procedures of the thyroid gland are performed in Germany. Strategies aimed at reducing the duration of the surgical procedure are relevant to patients and the health care system especially in the context of reducing costs. However, new techniques for quick and safe hemostasis have to be tested in clinically relevance randomized controlled trials before a general recommendation can be given. The current standard for occlusion of blood vessels in thyroid surgery is ligatures. Vascular clips may be a safe alternative but have not been investigated in a large RCT. METHODS/DESIGN: CLIVIT (Clips versus Ligatures in Thyroid Surgery) is an investigator initiated, multicenter, patient-blinded, two-group parallel relevance randomized controlled trial designed by the Study Center of the German Surgical Society. Patients scheduled for elective resection of at least two third of the gland for benign thyroid disease are eligible for participation. After surgical exploration patients are randomized intraoperatively into either the conventional ligature group, or into the clip group. The primary objective is to test for a relevant reduction in operating time (at least 15 min) when using the clip technique. Since April 2004, 121 of the totally required 420 patients were randomized in five centers. DISCUSSION: As in all trials the different forms of bias have to be considered, and as in this case, a surgical trial, the role of surgical expertise plays a key role, and will be documented and analyzed separately. This is the first randomized controlled multicenter relevance trial to compare different vessel occlusion techniques in thyroid surgery with adequate power and other detailed information about the design as well as framework. If significant, the results might be generalized and may change the current surgical practice

Irreversible Aging Dynamics and Generic Phase Behavior of Aqueous Suspensions of Laponite

In this work we study the aging behavior of aqueous suspension of Laponite having 2.8 weight % concentration using rheological tools. At various salt concentration all the samples demonstrate orientational order when observed using crossed polarizers. In rheological experiments we observe inherent irreversibility in the aging dynamics which forces the system not to rejuvenate to the same state in the shear melting experiment carried out at a later date since preparation. The extensive rheological experiments carried out as a function of time elapsed since preparation demonstrate the self similar trend in the aging behavior irrespective of the concentration of salt. We observe that the exploration of the low energy states as a function of aging time is only kinetically affected by the presence of salt. We estimate that the energy barrier to attain the low energy states decreases linearly with increase in the concentration of salt. The observed superposition of all the elapsed time and the salt concentration dependent data suggests that the aging that occurs in low salt concentration systems over a very long period is qualitatively similar to the aging behavior observed in systems with high salt concentration over a shorter period.Comment: 27 pages, 8 figures. Langmuir, in pres

Diffusing-wave spectroscopy of nonergodic media

We introduce an elegant method which allows the application of diffusing-wave spectroscopy (DWS) to nonergodic, solid-like samples. The method is based on the idea that light transmitted through a sandwich of two turbid cells can be considered ergodic even though only the second cell is ergodic. If absorption and/or leakage of light take place at the interface between the cells, we establish a so-called "multiplication rule", which relates the intensity autocorrelation function of light transmitted through the double-cell sandwich to the autocorrelation functions of individual cells by a simple multiplication. To test the proposed method, we perform a series of DWS experiments using colloidal gels as model nonergodic media. Our experimental data are consistent with the theoretical predictions, allowing quantitative characterization of nonergodic media and demonstrating the validity of the proposed technique.Comment: RevTeX, 12 pages, 6 figures. Accepted for publication in Phys. Rev.

Postsurgical pain outcome of vertical and transverse abdominal incision: Design of a randomized controlled equivalence trial [ISRCTN60734227]

BACKGROUND: There are two ways to open the abdominal cavity in elective general surgery: vertically or transversely. Various clinical studies and a meta-analysis have postulated that the transverse approach is superior to other approaches as regards complications. However, in a recent survey it was shown that 90 % of all abdominal incisions in visceral surgery are still vertical incisions. This discrepancy between existing recommendations of clinical trials and clinical practice could be explained by the lack of acceptance of these results due to a number of deficits in the study design and analysis, subsequent low internal validity, and therefore limited external generalisability. The objective of this study is to address the issue from the patient's perspective. METHODS: This is an intraoperatively randomized controlled observer and patient-blinded two-group parallel equivalence trial. The study setting is the Department of General-, Visceral-, Trauma Surgery and Outpatient Clinic of the University of Heidelberg, Medical School. A total of 172 patients of both genders, aged over 18 years who are scheduled for an elective abdominal operation and are eligible for either a transverse or vertical incision. To show equivalence of the two approaches or the superiority of one of them from the perspective of the patient, a primary endpoint is defined: the pain experienced by the patient (VAS 0–100) on day two after surgery and the amount of analgesic required (piritramide [mg/h]). A confidence interval approach will be used for analysis. A global α-Level of 0.05 and a power of 0.8 is guaranteed, resulting in a size of 86 patients for each group. Secondary endpoints are: time interval to open and close the abdomen, early-onset complications (frequency of burst abdomen, postoperative pulmonary complications, and wound infection) and late complications (frequency of incisional hernias). Different outcome variables will be ranked by patients and surgeons to assess the relevance of possible endpoints from the patients' and surgeons' perspective. CONCLUSION: This is a randomized controlled observer and patient-blinded two-group parallel trial to answer the question if the transverse abdominal incision is equivalent to the vertical one due to the described endpoints