8
views
0
recommends
+1 Recommend
0 collections
    0
    shares
      • Record: found
      • Abstract: found
      • Article: found
      Is Open Access

      Identification of the appropriate fixation site to avoid peritoneal catheter migration based on a mechanical analysis

      research-article

      Read this article at

      Bookmark
          There is no author summary for this article yet. Authors can add summaries to their articles on ScienceOpen to make them more accessible to a non-specialist audience.

          Abstract

          Aim: To conduct mechanical analysis on the relationship between abdominal wall fixation point and the displacement of catheter top, and establish the finite element model for the complex forces and conditions that the catheter wears in human abdominal cavity, in order to provide the scientific basis for optimizing the catheter position in abdominal wall fixation method.

          Methods: Using the PIPE59 finite elements to divide units, and taking the lower part of catheter, that is, below interior polyester cuff to simulate and compute the displacement formula.

          Results: The whole model includes a total of 1701 units. Periodic load was used to simulate the dynamic pressure that peritoneal dialysis catheter gets in abdominal cavity. The load direction was perpendicular to the catheter axis. We used pressure amplitude, duration and frequency as the boundary conditions, and adjusted the fixation point of the catheter lower part at the same time, thus calculating the extreme displacement value of the catheter top end with changing parameter conditions. We also did fitted regression on the results and obtained the displacement formula: y = 0.2 × 0.87 x (y: the end displacement of peritoneal dialysis catheter, x: the distance between fixation point and the interior polyester cuff), R 2: .982. Simulation the catheter maximal displacement on flat surface demonstrated that additional catheter fixation at the site of 9 cm or more below the internal cuff significantly restricted the catheter migration.

          Conclusions: The optimal position of fixation point in peritoneal dialysis is about 9 cm away from the interior polyester cuff.

          Related collections

          Most cited references22

          • Record: found
          • Abstract: found
          • Article: not found

          A finite element model of the human knee joint for the study of tibio-femoral contact.

          As a step towards developing a finite element model of the knee that can be used to study how the variables associated with a meniscal replacement affect tibio-femoral contact, the goals of this study were 1) to develop a geometrically accurate three-dimensional solid model of the knee joint with special attention given to the menisci and articular cartilage, 2) to determine to what extent bony deformations affect contact behavior, and 3) to determine whether constraining rotations other than flexion/extension affects the contact behavior of the joint during compressive loading. The model included both the cortical and trabecular bone of the femur and tibia, articular cartilage of the femoral condyles and tibial plateau, both the medial and lateral menisci with their horn attachments, the transverse ligament, the anterior cruciate ligament, and the medial collateral ligament. The solid models for the menisci and articular cartilage were created from surface scans provided by a noncontacting, laser-based, three-dimensional coordinate digitizing system with an root mean squared error (RMSE) of less than 8 microns. Solid models of both the tibia and femur were created from CT images, except for the most proximal surface of the tibia and most distal surface of the femur which were created with the three-dimensional coordinate digitizing system. The constitutive relation of the menisci treated the tissue as transversely isotropic and linearly elastic. Under the application of an 800 N compressive load at 0 degrees of flexion, six contact variables in each compartment (ie., medial and lateral) were computed including maximum pressure, mean pressure, contact area, total contact force, and coordinates of the center of pressure. Convergence of the finite element solution was studied using three mesh sizes ranging from an average element size of 5 mm by 5 mm to 1 mm by 1 mm. The solution was considered converged for an average element size of 2 mm by 2 mm. Using this mesh size, finite element solutions for rigid versus deformable bones indicated that none of the contact variables changed by more than 2% when the femur and tibia were treated as rigid. However, differences in contact variables as large as 19% occurred when rotations other than flexion/extension were constrained. The largest difference was in the maximum pressure. Among the principal conclusions of the study are that accurate finite element solutions of tibio-femoral contact behavior can be obtained by treating the bones as rigid. However, unrealistic constraints on rotations other than flexion/extension can result in relatively large errors in contact variables.
            Bookmark
            • Record: found
            • Abstract: found
            • Article: not found

            A model for the human cornea: constitutive formulation and numerical analysis.

            Abstract The human cornea (the external lens of the eye) has the macroscopic structure of a thin shell, originated by the organization of collagen lamellae parallel to the middle surface of the shell. The lamellae, composed of bundles of collagen fibrils, are responsible for the experimentally observed anisotropy of the cornea. Anomalies in the fibril structure may explain the changes in the mechanical behavior of the tissue observed in pathologies such as keratoconus. We employ a fiber-matrix constitutive model and propose a numerical model for the human cornea that is able to account for its mechanical behavior in healthy conditions or in the presence of keratoconus under increasing values of the intraocular pressure. The ability of our model to reproduce the behavior of the human cornea opens a promising perspective for the numerical simulation of refractive surgery.
              Bookmark
              • Record: found
              • Abstract: found
              • Article: not found

              A laparoscopic method for optimal peritoneal dialysis access.

              Both medical benefits to the patient and financial incentives to the health care system exist to increase the use of peritoneal dialysis as renal replacement therapy. Providing long-term peritoneal access free of mechanical dysfunction continues to represent a major challenge to the success of this modality. Variable outcomes result from the lack of standard implantation methodology and failure to address persistent problems associated with current implantation techniques. This prospective case study compared noninfectious procedural complications of three approaches to establish peritoneal dialysis access. The groups consisted of 63 catheters implanted by traditional open dissection, 78 catheters implanted by basic laparoscopy without associated interventions, and 200 catheters implanted by advanced laparoscopic methods including rectus sheath tunneling, selective prophylactic omentopexy, and selective adhesiolysis. Mechanical flow obstruction, the major outcome indicator, followed only 1 of 200 (0.5%) implantation procedures in the advanced group and was significantly better (P < 0.0001) than the open dissection (17.5%) and basic laparoscopic (12.5%) groups. A low rate of pericannular leaks (1.3-2%) was not different for the three groups. One pericannular hernia occurred in the open group. Catheter mechanical dysfunction attributable to the surgical technique can nearly be eliminated through adjunctive procedures made possible only by a laparoscopic approach.
                Bookmark

                Author and article information

                Journal
                Ren Fail
                Ren Fail
                IRNF
                irnf20
                Renal Failure
                Taylor & Francis
                0886-022X
                1525-6049
                2017
                22 February 2017
                : 39
                : 1
                : 400-405
                Affiliations
                [a ]Renal Department of Renmin Hospital, Wuhan University , Wuhan, PR China;
                [b ]School of Urban Construction, Wuhan University of Science and Technology , Wuhan, PR China;
                [c ]Division of General Surgery, First affiliated hospital of Chongqing Medical University , Chongqing, PR China
                Author notes
                CONTACT Huiming Wang wanghuimingwhm@ 123456yahoo.com ; Guohua Ding ghxding@ 123456gmail.com Renal Department of Renmin Hospital, Wuhan University , Jiefang Road 238, Wuchang District, Wuhan430060, PR China
                Article
                1291433
                10.1080/0886022X.2017.1291433
                6014350
                28222614
                42e1789e-602e-4376-867d-281d1a0f2ea6
                © 2017 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.

                This is an Open Access article distributed under the terms of the Creative Commons Attribution License ( http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                History
                : 14 December 2016
                : 30 January 2017
                Page count
                Pages: 6, Words: 3477
                Categories
                Laboratory Study

                Nephrology
                peritoneal dialysis,abdominal wall fixation,finite element method
                Nephrology
                peritoneal dialysis, abdominal wall fixation, finite element method

                Comments

                Comment on this article