Simple Traction Research Articles

Lead Management and Lead Extraction.

Management of patients with cardiac implantable electronic devices (CIEDs) has become complex given the complications that can occur with implanted lead systems. Clinical problems such as infection, lead failure, and occluded vessels create situations that demand intervention to remove leads. Due to adhesions that occur in the venous system and at the endomyocardial attachment site, simple traction to remove a lead is often not sufficient. Infection is a mandatory reason to remove the entire CIED system. Tools and techniques are now available that enable a skilled operator to extract leads with a great deal of efficacy and safety.

Instability detection of the tire-road contact and torque control for wheel-individual driven vehicles

Abstract Traction control for vehicles with wheel individual drives is a challenging task, since the wheel slips are unknown when each wheel transfers a torque. This contribution presents an approach which deals with this problem especially for electrical vehicles, where the drive torques can be changed very fast in comparison to vehicles with combustion engines. The algorithm is based on two filters. The first filter is an adaptive Kalman filter which is used to detect fast changes in the stability conditions of the wheels. The filter also delivers a valuation for the torque to which the drive torque has to be reduced to get the wheel stable again. The second filter estimates the wheel slip. It is based on a simplified expression of the slip dynamics in combination with a special reset strategy for low slip situations. This filter allows detection of slow changes in the stability conditions. All filters are wheel individual and use only standard sensor information. No tire model is needed for the filters to work. A simple reflexive traction controller, which is based on a state machine, computes the drive torques in dependence on the stability criteria based on the filter outputs.

Analysis of Helical Torsion Spring for Epicyclic Traction Drive

Let us consider a simple epicyclic traction drive containing a sun wheel, an annular wheel, planetary wheels and a planet carrier. The annular wheel is substituted by a helical torsion spring with rectangular cross section. The spring has initial tensioning, tightened to the planetary wheels. When the number of coils is z and the number of planet wheels is N, there are zN piece of concentrated forces acting to the spring from inside towards outside. The main load of the spring is bending, it is computable along the spring wire. The bending moment is limited by the spring material and the cross section of spring. The radial forces acting to the spring are governed by the constraint of stress equality, the deflections of the contacting parts are determined by the radial (and slightly the tangential) forces. An initial shape of the spring that assures the proper operation of the drive after the assembly, is calculated by elementary mechanical calculation methods. The main goal is the developing of a traction drive in which the clamping force is proportional to the torque which should be transmitted, for the sake of the favourable life rating and the efficiency.

Management of Pediatric Atlantoaxial Rotatory Subluxation with a Simple Handmade Cervical Traction Device: Doing More with Less

To introduce a novel traction device for management of pediatric atlanto-axial rotatory subluxation (AARS) in source limiting areas. Atlanto-axial (C1-C2) joint is accountable for up to two third of total axial craniocervical rotation. Its major role in pivotal rotation of cervical spine makes it more vulnerable to a certain type of injury known as AARS. Management of AARS is based on the Fielding classification which includes closed reduction and immobilization and cervical fusion in unstable cases. There are several cervical traction devices including the Gardner-Wells tongs and halter traction device. All the available devices require insertion of pins into the calvarial periosteum which is a painful, invasive and intolerable procedure especially for the pediatric patients. We designed a simple hand-made cervical traction device which is composed of 2 soft padded straps (40 × 4 cm) and 2 connecting strings which can be applied easily under the chin and occipital areas of the patients. We successfully treated a 9-year-old girl with AARS with the device. The advantage of the device is its available, inexpensive and non-invasive and the patient might tolerate it more easily compared to the previously designed instruments. This hand-made simple cervical traction device in source limiting centers and hospitals is a good example of doing more with less. It was effective and the tolerance of the patient was acceptable. Further studies with larger series are required for providing appropriate evidence.

Strategies for Transvenous Lead Extraction Procedures.

Transvenous lead extraction (TLE) has undergone an explosive evolution since its inception as a rudimentary skill with limited technology and therapeutic options. Early techniques involved simple manual traction that frequently proved ineffective for chronically implanted leads, and carried a significant risk of myocardial avulsion, tamponade, and death. The morbidity and mortality associated with these early extraction techniques limited their application to use only in life-threatening situations, such as infection and sepsis. The past four decades, however, have witnessed significant advances in lead extraction technology, resulting in more efficacious techniques and tools, providing the skilled extractor with a well-equipped armamentarium. With the development of the discipline, we have witnessed a growth in the community of TLE experts coincident with a marked decline in the incidence of procedure-related morbidity and mortality, with recent registries at high-volume centers reporting high success rates with exceedingly low complication rates. Future developments in lead extraction are likely to focus on new tools that will allow for us to provide comprehensive device management, develop alternative systems for extraction training, and focus on the design of new leads conceived to facilitate future extraction.

35 Uk multi-centre registry of transvenous lead extraction: clinical outcome using different techniques

IntroductionWith increasing numbers and complexity of implantable devices, the need for lead extraction is also increasing. There is little UK data available on clinical outcomes. We compiled a multi-centre registry...

Thin-wall composite sphere in finite shear deformation

We examine the mechanical response of an incompressible thin-wall composite sphere (TWCS) within the framework of finite deformation elasticity. Specifically, we consider TWCSs with a neo-Hookean core phase and a stiffer or a softer shell subjected to simple shear displacement and traction boundary conditions. We derive the general forms of the displacement and the pressure fields in both phases in terms of a power series about the shear magnitude. The predictions of the analytical solutions are analyzed and compared with corresponding results of finite element simulations. In order to examine the range of the validity of the thin shell assumption we model TWCSs with shell volume fractions of 5 and 10%.We find that a relatively small number of terms in the series is required for a good agreement with the numerical simulations in the cases of TWCSs with a stiffer shell under displacement boundary condition and TWCSs with a softer shell under traction boundary conditions. For the dual pair of TWCSs with a softer or stiffer shell under displacement or traction boundary conditions, respectively, the analytical solution is applicable only when the contrast between the phases shear moduli is considerably smaller than the shell volume fraction. Moreover, for each of the above pairs the spatial distributions of the stresses in the core are rather similar. In the shell, however, the stress distributions depend primarily on the contrast between the shear moduli of the two phases. At the macro-level we find that while the stored strain energy is identical in TWCSs subjected to identical magnitudes of shear strain or shear stress under both types of boundary conditions, a Poynting effect is observed in the finitely deforming TWCSs.

Reducing Shoulder by Vertical Traction: A One-Man Method for Shoulder Reduction

Fifty percent of joint dislocations reported to the emergency department are of shoulder joint. Various techniques are used to reduce the shoulder and Spaso technique is the least known to the orthopaedic residents which is a simple one-man vertical traction method of shoulder reduction. We evaluated the effectiveness of vertical traction method for anterior shoulder dislocation by orthopaedic residents. Sixty consecutive patients of anterior glenohumeral dislocation attending the emergency department of our hospital were taken up for the study. The reduction was done using Spaso technique. Right shoulder was dislocated in 40 patients and 31 patients had recurrent shoulder dislocation. In 55 patients, shoulder was reduced without the use of any anaesthesia. In patients where no anaesthesia was used, the time of traction ranged from 45 seconds to 5 minutes, while under anaesthesia the time of traction ranged from 1 to 4 minutes. Twenty-one patients had associated greater tuberosity fracture which did not affect the method of reduction and all of them were reducible. No complication was reported, and all the patients were satisfied with the method. In conclusion vertical traction method is a good technique for reducing anterior shoulder dislocation with an easy learning curve among the residents and no complication has been reported so far.

Feasibility of Simple Traction Technique for Rectal Endoscopic Submucosal Dissection.

Rectal endoscopic submucosal dissection (ESD) is a highly effective procedure that achieves high en bloc resection regardless of lesion size or location. However, rectal ESD has a higher risk of intraoperative and postoperative bleeding and still difficult for beginners. Therefore, we designed a novel traction technique "traction-assisted rectal ESD using a clip-with-line (TAREC)," and investigated its feasibility. Between December 2014 and July 2015, ten patients with rectal neoplasms (median size 36mm; range 20-125mm) were treated using the TAREC technique. In all lesions, good visibility of the submucosal layer was obtained, and the submucosal layer was dissected easily under direct visualization. All lesions were removed en bloc, and there were no procedure-related adverse events including postoperative bleeding. In particular, we experienced no intraoperative bleeding, which may be difficult to stop in some circumstances. The TAREC technique is a simple and generally applicable procedure. This technique is feasible for rectal ESD.

Transvenous Lead Extraction via the Inferior Approach Using a Gooseneck Snare versus Simple Manual Traction.

Background and ObjectivesThe number of patients with cardiac implantable electronic devices needing lead extraction is increasing for various reasons, including infections, vascular obstruction, and lead failure. We report our experience with transvenous extraction of pacemaker and defibrillator leads via the inferior approach of using a gooseneck snare as a first-line therapy and compare extraction using a gooseneck snare with extraction using simple manual traction.Subjects and MethodsThe study included 23 consecutive patients (43 leads) who underwent transvenous lead extraction using a gooseneck snare (group A) and 10 consecutive patients (17 leads) who underwent lead extraction using simple manual traction (group B). Patient characteristics, indications, and outcomes were analyzed and compared between the groups.ResultsThe dwelling time of the leads was longer in group A (median, 121) than in group B (median, 56; p=0.000). No differences were noted in the overall procedural success rate (69.6% vs. 70%), clinical procedural success rate (82.6% vs. 90%), and lead clinical success rate (86% vs. 94.1%) between the groups. The procedural success rates according to lead type were 89.2% and 100% for pacing leads and 66.7% and 83.3% for defibrillator leads in groups A and B, respectively. Major complications were noted in 3 (mortality in 1) patients in group A and 2 patients in group B.ConclusionTransvenous extraction of pacemaker leads via an inferior approach using a gooseneck snare was both safe and effective. However, stand-alone transvenous extraction of defibrillator leads using the inferior approach was suboptimal.

Modified snare removal of a retained lead

Article history: Received 24 October 2015 Accepted 26 October 2015 Available online 9 November 2015 tation the old one was attempted to be removed manually by performing simple traction. The proximal portion of the lead, however, was torn and retained. Two and a half years after the second procedure the pulse generator was explanted and proximally cut leads were left in the pocket because of pocket infection. Just before being referred to our center some retained leads protrude from the pectoral skin. Nonpowered extraction tools, locking stylets (Lead Locking Device® EZ,

Usefulness of a traction method using dental floss and a hemoclip for gastric endoscopic submucosal dissection: a propensity score matching analysis (with videos)

Although endoscopic submucosal dissection (ESD) is a significant advancement in therapeutic endoscopy, it is a complicated technique and requires considerable expertise. In this exploratory study, we evaluated the efficacy of a simple traction method that uses dental floss and a hemoclip (DFC) and was developed to overcome the technical difficulties of ESD. In total, 238 early gastric cancers treated by ESD between May 2012 and December 2014 at Tokyo Medical University were retrospectively reviewed. Lesions treated by conventional ESD (n = 185) and by ESD with DFC (ESD-DFC) (n = 53) were compared. Multivariable analyses and propensity score matching were used to compensate for the differences in age, sex, resected specimen size, lesion location, lesion position, presence of ulceration, and operator level. The procedure time, rate of en bloc and complete resection, and rates of adverse events were evaluated between the 2 groups. Propensity score matching analysis created 43 matched pairs. Adjusted comparisons between ESD-DFC and conventional ESD showed similar treatment outcomes (en bloc resection rate: 97.7% vs 100%, P = .315; complete resection rate: 90.7% vs 95.3%, P = .397; perforation during ESD rate: 2.3% vs 2.3%, P = 1.000; post-ESD bleeding rate: 4.7% vs 4.7%, P = 1.000) but a significantly shorter procedure time for ESD-DFC (82.2 ± 79.5 minutes vs 118.2 ± 71.6 minutes, P = .002). ESD-DFC facilitated rapid ESD with good visualization and traction while ensuring high curability and safety.

Percutaneous lead extraction by femoral approach, case report

BackgroundTransvenous lead extraction is usually done via subclavian route, here we present an extraction case performed by femoral approach. Case report72year old patient who has a VVI pacemaker with one passive fixation and one active fixation lead admitted to our clinic with pacemaker decubitus. We decided to remove all hardwares and insert a new battery and lead on contralateral side. However the first passive lead was deep inside the subclavian region so we planned to use femoral approach for lead extraction if subclavian approach fails in the patient. In the catheterization laboratory active fixation lead is easily explanted by simple traction but the passive lead could not be reached by subclavian approach. We decided to use the femoral Byrd Workstation 12F™ and Needle's eye Snare® to extract lead femorally. The lead is snared at subclavian end and is extracted by applying gentle simple traction and taken into the femoral Byrd Workstation 12F™. We implanted new pacemaker at contralateral side and discharged patient uneventfully. ConclusionPercutaneous femoral approach for lead extraction is generally used as bail-out procedure for leads that cannot be extracted by subclavian approach but as in our case it can be used primarily according to the clinical presentation of the patient.

How adequate are the current methods of lead extraction? A review of the efficiency and safety of transvenous lead extraction methods.

Currently several extraction tools are available in order to allow safe and successful transvenous lead extraction (TLE) of pacemaker and ICD leads; however, no directives exist to guide physicians in their choice of extraction tools and approaches. To aim of the current review is to provide an overview of the success and complication rates of different extraction methods and tools available. A comprehensive search of all published literature was conducted in the databases of PubMed, Embase, Web of Science, and Central. Included papers were original articles describing a specific method of TLE and the corresponding success rates of at least 50 patients. Fifty-three studies were included; the majority (56%) utilized 2 (1-4) different venous extraction approaches (subclavian and femoral), the median number of extraction tools used was 3 (1-6). A stepwise approach was utilized in the majority of the studies, starting with simple traction which resulted in successful TLE in 7-85% of the leads. When applicable the procedure was continued with non-powered tools resulting in a successful extraction of 34-87% leads. Subsequently, powered tools were applied whereby success rates further increased to 74-100%. The final step in TLE was usually utilized by femoral snare leading to an overall TLE success rate of 96-100%. The median procedure-related mortality and major complication described were, respectively, 0% (0-3%) and 1% (0-7%) per patient. In conclusion, a stepwise extraction approach can result in a clinical successful TLE in up to 100% of the leads with a relatively low risk of procedure-related mortality and complications.

Non-linear elastic micro-dilatation theory: Matrix exponential function paradigm

In the present paper, the micro-dilatation theory or void elasticity is extended to both large displacement and large dilatation. Firstly, the deformation gradient tensor has been freshly defined by means of the matrix exponential function. The newly defined relation for the deformation gradient has painstakingly investigated for the uniqueness, decomposition issues as well as objectivity and isotropy considerations. The relation of the displacement gradient and deformation gradient tensor is brought via the matrix logarithm function. The micro-dilatation theory constitutive laws are derived using the thermodynamic principles under the zero-centrosymmetric, weakly-centrosymmetric and fully-centrosymmetric cases. These cases have been derived and scrutinized by the numerical experiments. To achieve this assignment, the basic loadings are taken into account, e.g. the hydrostatic loading, simple traction and shear. Some conclusions and outlook pertaining to the above-mentioned cases and variable bulk density have thereafter discussed.

A Retained Epidural Catheter Fragment Treated by Surgery.

The breakage of an epidural catheter is an extremely rare complication. We describe a unique case where a retained epidural catheter fragment after epidural anesthesia was treated by surgery. The epidural catheter broke during its removal, requiring surgery to remove the retained catheter. Intraoperatively, the removal of the catheter was attempted by simple traction, but was impossible because of the adhesion. The adhesion of the dura mater surface was carefully exfoliated and the successful removal of the catheter was accomplished. Conventionally, it was said that this follow-up was enough for the retained catheter. However, if a catheter is retained within the spinal canal, surgical removal should thus be considered before the adhesion advances.

Širdies perforacija elektrokardiostimuliatoriumi: klinikinis atvejis

ĮvadasViena iš retų elektrokardiostimuliatoriaus ar defibriliatoriaus implantacijos komplikacijų yra širdies perforacija. Jos klinikinės išraiškos pasižymi didele įvairove ir gali sukelti daug diagnostikos sunkumų.Klinikinis atvejisĮ mūsų ligoninę dėl sinusinio mazgo silpnumo sindromo hospitalizuotas 80 metų ligonis. Jam implantuotas dviejų kamerų ilgalaikis kardiostimuliatorius. Procedūros komplikacijos – širdies perforacija, hemoperikardiumas ir dešinės pusės hemoto­raksas. Po procedūros praėjus kelioms valandoms, ligonis pasijuto blogai, tačiau tiksli širdies perforacijos diagnozė nustatyta tik penktą dieną po kardiostimuliatoriaus implantavimo, kai atlikta krūtinės ląstos kompiuterinė tomografija. Tuomet elek­trofiziologas, padedamas chirurgų, kontroliuojant procedūrą torakoskopu, pašalino migravusį elektrokardiostimuliatoriaus elektrodą. Kitą dieną ligoniui įdėtas naujas elektrodas. Praėjus šešiolikai dienų po elektrokardiostimuliatoriaus implantavimo, vyras išrašytas iš ligoninės.Išvados Literatūroje minima, kad dauguma migravusių elektrodų gali būti paprastai ištraukti kontroliuojant procedūrą rentgenu ar stebint echokardiografu operacinėje, kartu esant pasirengusiai chirurgų komandai. Mes sėkmingai pašalinome elektrodą kontroliuodami procedūrą torakoskopu.

Fracture of DF-4 implantable cardioverter defibrillator lead in a pediatric patient.

Sir, A 10-year-old girl with a left ventricle noncompaction and strong family history of sudden cardiac death had received transvenous implantable cardioverter defibrillator (ICD; Evera VR, Medtronic Inc, Minneapolis, MN, USA). Device was implanted in the left subpectoral area using a left axillary vein access. Venous puncture was performed using the first rib technique under fluoroscopy guidance with no difficulties. A single coil DF-4 ICD lead (Medtronic, Sprint Quatro 6935M -62 cm) was inserted and positioned at the right ventricular apex with excellent sensing and pacing parameters. She presented 1year later with device alarm and was found to have a high ICD lead pacing impedance (>3,000 Ω), undetectable R-wave, and non-capture. The Lead Integrity Alert prevented inappropriate shocks. She was not involved in any form of competitive sport or direct trauma. Fluoroscopy showed lead fracture [Figure 1]. The patient underwent ICD lead extraction using a simple traction with the aid of a Lead Locking Device (Spectranetics, Colorado Springs, CO, USA). Although the polyurethane surrounding the lead was intact, a conductor fracture could be observed through the insulation about 1 cm beyond the tie down. A new ICD lead then was implanted.Figure 1: Fluoroscopy showed lead fractureThe evolution of new leads technology simplified the implantation techniques and improved the pocket profile particularly in pediatrics; however, this technology is yet to be evaluated. The first report of aDF-4 ICD lead fracture highlighted the possible mechanism of fracture.[1] A multicenter post-approval study for St. Jude Medical™ DF-4 system showed a 0.1% fracture rate;[2] however, the mechanism of the lead fracture was not described in this study. In our report, we described aDF-4 ICD lead fracture in a pediatric patient. Although the lead was angulated at the entry point into the vein, we think this is not enough to explain the lead fracture. Given the increasing number of DF-4 ICD lead implantation in the recent years, such lead fracture may gain more attention.

Abstract 11914: Coronary Sinus Lead Extraction_Laser Required

Introduction: Studies of coronary sinus (CS) lead extraction have reported high success rates with manual traction, but largely included leads with dwell times less than 3 years. Our aim was to evaluate CS lead extractions of more chronic leads and establish if dwell time was correlated to complexity of extraction. Methods: This is a single center, retrospective review of 96 consecutive lead extraction procedures. A total of 14 CS leads were identified. Results: Of the 14 CS lead extractions, 13 were successful from an endovascular approach. Indications included 8 cases of endocarditis, 4 pocket infections, 1 dislodged lead and 1 malfunctioning lead. Six extractions were performed with manual traction, dwell time of these leads ranged from 5 months to 28 months, with an average implant time of 10.8 months. Eight extractions required use of a laser sheath (LS) to free the lead from adhesions. In no case was the LS used within the CS. The dwell time of these leads ranged from 45 months to 114 months, with an average lead age of 83.4 months. One LS case also required use of a rotating mechanical sheath. In one LS assisted extraction, the lead fragmented within the CS and could not be recovered endovascularly despite the use of multiple snares. This lead fragment was removed via an open surgical approach. Conclusion: CS leads require the use of advanced extraction tools in the majority of patients. All leads placed in the preceding 28 months were removed with simple manual traction, however all leads that were in place for more than 3 years required use of a LS. In contrast to prior reports, we found that coronary sinus leads posed the same procedural challenges as other cardiac leads and typically require advanced extraction tools.

Use of silicone tracheal stoma stents for temporary tracheostomy in dogs with upper airway obstruction.

To report the use of silicone tracheal stoma stents for temporary tracheostomy in dogs with upper airway obstruction. Retrospective review of medical records for dogs in which silicone tracheal stoma stents were placed. Eighteen dogs had a silicone tracheal stoma stent placed for maintenance of a tracheostomy stoma for periods ranging from three hours to eight months. No intra-operative or immediate postoperative complications were recorded. In 11 dogs the stent was removed by simple traction after a period ranging from 36 hours to 6 weeks, and the tracheal stoma was left to heal by second intention. Five of the 18 dogs were determined as being tracheostomy dependent and underwent conversion to permanent tracheostomy after a period ranging from five days to eight months following stent placement. One dog was euthanased after three months, with the stent still in place, because of poor respiratory function, and one dog died of unrelated reasons. In 6 of 10 dogs (60%) where the stent was in place for five days or more, granulation tissue formation caused dislodgement of the stent. Silicone tracheal stoma stents may be used as an alternative to conventional tracheostomy tubes in selected dogs with upper airway obstruction. Long-term use of the stent beyond five days is not recommended because of granulation tissue formation. The long-term consequences of partial tracheal ring resection are unknown.