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Access Devices (access + device)
Kinds of Access Devices Selected AbstractsDesign and Test of a Vascular Access DeviceARTIFICIAL ORGANS, Issue 5 2000Gijsbertus Jacob Verkerke Abstract: Transarterial left ventricular assist devices (LVADs), such as the Hemopump, IABP, and PUCA-pump, are meant to be introduced into the body via the femoral or axillary artery without major surgery. For certain applications, introduction is performed directly into the aorta via an open thorax procedure. A prototype of a vascular access device has been realized that allows direct access into the aorta as an alternative for the common surgical graft anastomosis suturing technique. The device consists of a metal tube acting as a circular knife to cut a hole in the aortic wall, a screw to store the removed part of the aortic wall, and a plastic tube that is introduced through the hole and tightly connected to the aortic wall. The device could be placed without aortic clamping. The device has been tested on a slaughterhouse porcine aorta. A low-pressurized aorta appeared to be the worst case; thus, two animal experiments in the low-pressurized pulmonary artery were performed. No leakage occurred for pressures between 40 and 300 mm Hg. [source] Central venous access devices for paediatric patients with haemophilia: a single-institution experienceHAEMOPHILIA, Issue 1 2009R. TITAPIWATANAKUN Summary., Use of a central venous access device (CVAD) can facilitate early introduction of home-based infusion of factor concentrate for long-term prophylaxis or immune tolerance therapy in children with bleeding disorders. The aim was to review outcomes associated with use of CVAD. Retrospective review of paediatric patients with bleeding disorders was observed at the Mayo Clinic Comprehensive Hemophilia Center. Thirty-seven CVAD were placed in 18 patients (haemophilia A [n = 15], type 3 von Willebrand disease [n = 2] and haemophilia B [n = 1]). Follow-up was for 45 952 CVAD days, and median time that CVAD remained in place was 1361 days per device. Factor VIII (FVIII) inhibitors were present in 4 of the 15 patients. Ten CVAD-related infections occurred (median, 672 days; range, 72,1941 days), of which six were in one patient with FVIII inhibitors. Overall infection rate was 0.22 (95% confidence interval [CI], 0.10,0.40) per 1000 CVAD days, with 0.11 infections in patients without FVIII inhibitors compared with a pooled incidence of 0.66 (95% CI, 0.44,0.97) reported in the literature. Indications for removal of 27 CVAD were blockage, change to peripheral venous access, catheter displacement, infection, leak in the port septum, short catheter and skin erosion. No clinically apparent thrombosis or sequelae of thrombosis were observed. Infection is the most common complication associated with CVAD use and is increased in patients who have inhibitors. The low rate of clinically apparent thrombosis reflects our practice of not screening for thrombosis. The low infection rate reflects our practice of using and reinforcing the aseptic technique. [source] Prospective investigation of a subcutaneous, implantable central venous access device for therapeutic plasma exchange in adults with neurological disordersJOURNAL OF CLINICAL APHERESIS, Issue 1 2002Basilio Pertiné Abstract Standard alternatives to antecubital access for long-term therapeutic plasma exchange, including percutaneous polyurethane or tunneled silicone catheters, are associated with complications and inconvenience for the patient. We have investigated the Bard CathLink® 20, a subcutaneously implantable central venous access device, as an alternative for outpatient plasma exchange. The CathLink® 20 consists of a funnel-shaped titanium port connected to a soft polyurethane-derived catheter and is accessed percutaneously using an 18-gauge catheter-over-needle Angiocath®. Six patients with paraproteinemic polyneuropathies underwent 64 outpatient plasma exchanges using the CathLink® 20 for access, 31 using 2 CathLink® 20's (draw and return), 20 using a single CathLink® 20 as the draw site and 13 using a single CathLink® 20 as the return site. Mean (± SD) plasma removed was 3,680 ± 551 ml in 115.2 ± 25.3 min. Apheresis personnel were able to access the ports in 1.23 ± 0.6 attempts per port per procedure. Six of 70 planned procedures were aborted: 3 because of failure of an antecubital access site and 3 because of catheter occlusion resolved using a thrombolytic agent. Whole blood flow rate was approximately 54 ml/min, and plasma flow rate was about 32 ml/min for 135 min. Access pressures were stable at ,150 to ,200 torr (P = 0.1395). Return line pressures varied between 90 and 130 torr (P = 0.0147). No patient required hospitalization during the study. Though not optimized for apheresis, the CathLink® 20 provides a reasonable option for chronic apheresis patients who lack adequate peripheral venous access. J. Clin. Apheresis 17:1,6, 2002. © 2002 Wiley-Liss, 2002. [source] Robotic-assisted single-incision laparoscopic partial cecectomyTHE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 3 2010Madhu Ragupathi Abstract Background Single-incision laparoscopic surgery is an emerging approach in the field of minimally invasive colon and rectal surgery. This modality utilizes a ,scarless' incision concealed within the umbilicus, and results in improved cosmesis with the potential for reduced trauma, pain and length of hospital stay. However, unique technical challenges have curbed its adaptation. Robotic-assisted technique may help overcome these limitations when applied to the single-incision approach. Methods A robotic-assisted single-incision laparoscopic partial cecectomy was performed using the da Vinci® robot and the GelPOINTÔ access device. Modifications of the robotic set-up were utilized to optimize the technique. The robotic instruments were crossed below the abdominal wall to minimize internal conflict and maximize range of motion. Control of the robotic arms was reassigned on the robotic console to create a more intuitive surgical approach. The robotic camera was rotated and positioned vertically to reduce external conflict and enhance visualization. Results Robotic-assisted single-incision laparoscopic partial cecectomy was performed in a 53 year-old male without complication or need for conversion. The procedure required 120 min with an estimated blood loss of < 50 ml. Pathology revealed a sessile tubular adenoma of the cecum. The length of hospital stay was 2 days and no complications were encountered. The patient returned with a well-healed 2.5 cm incision and no postoperative complications at 6 weeks follow-up. Conclusions With appropriate modifications, robotic-assisted single-incision laparoscopic surgery may be applicable as a minimally invasive modality for partial colectomy. Further studies are warranted to establish the safety, efficacy, benefits, and limits of this technique. Copyright © 2010 John Wiley & Sons, Ltd. [source] Design and Test of a Vascular Access DeviceARTIFICIAL ORGANS, Issue 5 2000Gijsbertus Jacob Verkerke Abstract: Transarterial left ventricular assist devices (LVADs), such as the Hemopump, IABP, and PUCA-pump, are meant to be introduced into the body via the femoral or axillary artery without major surgery. For certain applications, introduction is performed directly into the aorta via an open thorax procedure. A prototype of a vascular access device has been realized that allows direct access into the aorta as an alternative for the common surgical graft anastomosis suturing technique. The device consists of a metal tube acting as a circular knife to cut a hole in the aortic wall, a screw to store the removed part of the aortic wall, and a plastic tube that is introduced through the hole and tightly connected to the aortic wall. The device could be placed without aortic clamping. The device has been tested on a slaughterhouse porcine aorta. A low-pressurized aorta appeared to be the worst case; thus, two animal experiments in the low-pressurized pulmonary artery were performed. No leakage occurred for pressures between 40 and 300 mm Hg. [source] Comparison between objective and subjective measurements of quality of service over an Optical Wide Area networkEUROPEAN TRANSACTIONS ON TELECOMMUNICATIONS, Issue 3 2008Francesco Matera The introduction of intelligence for management and control of the quality of service (QoS) are key issues for the evolution of the next generation IP optical network based on Ethernet technology. A test bed of a core-access network was implemented to investigate such issues and in this paper, the authors report measurements concerning the QoS of multimedia services for different traffic conditions. The network was implemented with a differentiated service over Multi-Protocol Label Switch (MPLS) architecture; it consists of a real optical network based on core routers with optical Gigabit Ethernet (GBE) interfaces connected by means of long single mode fibres (about 50\,km), contained in an installed cable between Rome and Pomezia. The network is based on different access devices, but in this paper we only refer to an access based on Fibre To The building (FTTB) architecture. The QoS was investigated both in terms of network (or objective) tests that include packet loss, jitter, one way delay and throughput measurements and perceptive (or subjective) tests that conversely are based on the evaluation of user perception. The services under test mainly consisted of video streams that circulated in the network according to the switching operations based in the IP differentiated service over MPLS technique that allowed us to guarantee the QoS for some class of service, also in the presence of network overload. Particular attention was given to the correlation between objective and subjective measurements. Furthermore, in order to have a complete analysis about QoS of real networks, measurements were performed also in the presence of restoration operations for link failures; in particular we compare the results in the case of conventional IP network restoration with a procedure proposed by us and based on a link switching activated by the loss of signal command coming from the routers. Copyright © 2007 John Wiley & Sons, Ltd. [source] Ethanol lock therapy for the treatment of catheter-related infections in haemophilia patientsHAEMOPHILIA, Issue 6 2009M. RAJPURKAR Summary., Central venous access devices (CVAD) are increasingly being used for optimal delivery of clotting factor concentrates in patients with haemophilia with poor peripheral venous access. The utility of CVAD is particularly well recognized in young patients starting factor prophylaxis and in patients with inhibitors undergoing immune tolerance induction (ITI). A catheter-related infection (CRI) remains the most common complication of CVAD in haemophilia patients and is the most frequent indication for its removal. Additionally, in some patients the infection results in significant morbidity and mortality and also contributes to failure of the ITI regimen. Ethanol-lock therapy (ELT) is a treatment modality that has been used to treat CRI in patients with indwelling catheters for home parenteral nutrition and chemotherapy. The aim of this study was to report the success in treating CRI in haemophilia patients using ELT. Three severe haemophilia A patients undergoing ITI regimen who developed CVAD infections resistant to conventional management with antibiotics were treated by ELT according to the institutional technique. All three patients responded well to ELT with clearance of the CVAD infection. There were no adverse side effects. To our knowledge, this is the first report of ELT in patients with haemophilia. The role of ELT needs to be investigated in larger studies for treatment of CRI in patients with bleeding disorders. [source] Central venous access devices for paediatric patients with haemophilia: a single-institution experienceHAEMOPHILIA, Issue 1 2009R. TITAPIWATANAKUN Summary., Use of a central venous access device (CVAD) can facilitate early introduction of home-based infusion of factor concentrate for long-term prophylaxis or immune tolerance therapy in children with bleeding disorders. The aim was to review outcomes associated with use of CVAD. Retrospective review of paediatric patients with bleeding disorders was observed at the Mayo Clinic Comprehensive Hemophilia Center. Thirty-seven CVAD were placed in 18 patients (haemophilia A [n = 15], type 3 von Willebrand disease [n = 2] and haemophilia B [n = 1]). Follow-up was for 45 952 CVAD days, and median time that CVAD remained in place was 1361 days per device. Factor VIII (FVIII) inhibitors were present in 4 of the 15 patients. Ten CVAD-related infections occurred (median, 672 days; range, 72,1941 days), of which six were in one patient with FVIII inhibitors. Overall infection rate was 0.22 (95% confidence interval [CI], 0.10,0.40) per 1000 CVAD days, with 0.11 infections in patients without FVIII inhibitors compared with a pooled incidence of 0.66 (95% CI, 0.44,0.97) reported in the literature. Indications for removal of 27 CVAD were blockage, change to peripheral venous access, catheter displacement, infection, leak in the port septum, short catheter and skin erosion. No clinically apparent thrombosis or sequelae of thrombosis were observed. Infection is the most common complication associated with CVAD use and is increased in patients who have inhibitors. The low rate of clinically apparent thrombosis reflects our practice of not screening for thrombosis. The low infection rate reflects our practice of using and reinforcing the aseptic technique. [source] Home management of haemophiliaHAEMOPHILIA, Issue 2 2004J. M. Teitel Summary., The demonstrated benefits of home care for haemophilia include improved quality of life, less pain and disability, fewer hospitalizations, and less time lost from work or school. Although reduced mortality has not been demonstrated, the substantial increase in longevity since the early 1980s correlates with the introduction of home treatment and prophylaxis programmes. These programmes must be designed and monitored by haemophilia treatment centres (HTC), which are staffed with professionals with broad and complementary expertise in the disease and its complications. In return, patients and their families must be willing to accept the reciprocal responsibilities that come from administering blood products or their recombinant equivalents at home. Patients with inhibitors to factors VIII or IX pose special challenges, but these complications do not obviate participation in home care programmes. Home care was an essential prerequisite to the introduction of effective prophylactic factor replacement therapy. Prophylaxis offers significant improvements in quality of life, but requires a substantial commitment. The use of implantable venous access devices can eliminate some of the difficulty and discomfort of peripheral venous access in small children, but brings additional risks. The future holds the promise of factor concentrates for home use that have longer half-lives, or can be administered by alternate routes. Knowledge of patient genotypes may allow treatments tailored to avoid complications such as inhibitor development. Gene therapy trials, which are currently ongoing, will ultimately lead to gene-based treatments as a complement to traditional protein-based therapy. [source] Central venous lines in haemophiliaHAEMOPHILIA, Issue 2003R. Ljung Summary., Infections and technical problems are the most frequent complications when using implantable central venous access devices in patients with haemophilia. There are two major experiences reported concerning infections in noninhibitor patients: one is approximately 0.2 infections per 1000 days and the other approximately 1.0 (0.7,1.6) per 1000 days. Infections are more frequent in inhibitor patients and approximately one infection per 6,12 months of use can be expected. The figures are low for clinically apparent thrombosis in the larger series on record, but routine venograms were not carried out in most of these series. In studies where this has been done, a high frequency of abnormalities on venograms has been seen in some but not in others. The final decision to use a central line has to take into account the medical goal, the patient's bleeding tendency, the social situation and the expected risk of complications at the particular haemophilia centre. Some of the complications may be reduced by adequate aseptic measures both during implantation and in subsequent use, and by clear basic routines for surveillance of the systems and repeated education of the users. [source] The economics and practicality of t-PA vs tunnel catheter replacement for hemodialysisHEMODIALYSIS INTERNATIONAL, Issue 1 2005Cairoli O. Kaiser Permanente Introduction:,Thrombolytic therapy is an important treatment modality for thrombosis-related catheter occlusion. Central venous access devices (CAVDs) are essential tools for the administration of many therapeutic modalities, especially for patients requiring lifetime therapy like hemodialysis. There are several reasons to salvage the occluded catheter. Catheter replacement results in an interruption of therapy delivery. This interruption may result in complications such as life-threatening metabolic and physiologic states. In addition, the patient's future access sites for CAVDs may be affected. The data released in the 2001 Annual Report , ESRD Clinical Performance Measures Project (Department of Health and Human Services, December 2001) shows 17% of prevalent patients were dialyzed with a chronic catheter continuously for 90 days or longer. In the pediatric population the data shows that 31% were dialyzed with a chronic catheter. The most common reasons for catheter placement included: no fistula or graft created (42%) and fistula and graft were maturing, not ready to cannulate (17%). Five percent of patients were not candidates for fistula or graft placement as all sites had been exhausted. Methods:,A short study was done in our medical center to evaluate the results of t-PA vs. changing the tunnel catheter. On an average a catheter costs about $400.00. If you add the cost of specialty personnel such as an interventional radiologist, radiology technician, radiology nurse, and the ancillaries such as the room, sutures, gauze, and tape, the total could reach $2000.00 easily. CathfloÔ Activase® costs around $60.00 for a single dose. T-PA was reconstituted by pharmacy personnel in single vials containing 2 mg/2 ml. Now with Cathflo, vials are stored in the renal clinic's refrigerator and when the need arises, the RN reconstitutes the medication. The RN, using established protocols, will instill Cathflo in the catheter following the volume requirements of the various tunnel catheters. After the t-PA is placed, the patient is sent home with instructions to return to their dialysis center the next day (arrangements are made by the RN as needed). In seventeen patients (17) with tunnel catheter malfunctions due to inadequate flow, not related to placement, t-PA was used. Of those 17 patients 2 were unable to use their catheter on their next dialysis treatment date, yielding an 88% success rate. This compares with clinical trials in which there is an 83% success rate with a dwell time of 4 hours, or an 89% rate on patients having a 2 hour dwell time (t-PA was repeated a second time if flow was not successfully restored. Results:,15/17 patients in our retrospective study showed that Cathflo worked successfully in restoring blood flow. Two catheters needed to be exchanged. The cost savings were significant when we compared the average cost of an exchange ($2000) versus using t-PA ($170 including nursing time). Conclusion:,Cathflo is not just safe and practical to use but also cost effective. [source] Guidelines on the insertion and management of central venous access devices in adultsINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 4 2007L. BISHOP Summary Central venous access devices are used in many branched of medicine where venous access is required for either long-term or a short-term care. These guidelines review the types of access devices available and make a number of major recommendations. Their respective advantages and disadvantages in various clinical settings are outlined. Patient care prior to, and immediately following insertion is discussed in the context of possible complications and how these are best avoided. There is a section addressing long-term care of in-dwelling devices. Techniques of insertion and removal are reviewed and management of the problems which are most likely to occur following insertion including infection, misplacement and thrombosis are discussed. Care of patients with coagulopathies is addressed and there is a section addressing catheter-related problems. [source] | ||||||||||