Device Failure Rate Research Articles

Characteristics of intramedullary nail breakage in pertrochanteric femur fractures: a summary of 70 cases

ObjectiveTo reveal noteworthy characteristics of intramedullary (IM) nail breakage in pertrochanteric femur fractures.Materials and methodsThe data from 6 patients with IM nail breakage in our hospital between August 2008 and May 2018 were reviewed retrospectively. With an additional 64 cases reported in articles in the PubMed database prior to October 2019, a total of 70 cases were reviewed and analysed; epidemiological patient data and data on the initial trauma, fracture type, nail selected for the original surgery, time from surgery to breakage, mechanism and location of breakage, status of fracture healing, salvage treatment and prognosis were assessed.ResultsSeventy patients with pertrochanteric fractures, including 2 stable fractures and 68 unstable fractures, experienced IM nail breakage at a mean of 9.4 months after the initial surgery. Among them, 9 (12.9%) occurred within 3 months, 23 (32.9%) between 3 and 6 months and 38 (54.3%) after 6 months. The mean age was 72.3 years, and 16 (22.9%) patients were younger than 65 years old. When nail breakage occurred, 66 fractures (94.3%) exhibited delayed union/non-union. Self-dynamisation was found in 12 cases (17.1%). The salvage procedures included 4 partial/total implant removal procedures, 17 hemi/total hip arthroplasty procedures, 3 conservative treatment procedures, and 46 revised osteosyntheses, of which 7 cases (15.2%) sustained secondary implant failure. No significant differences were found between the failure rates of IM nails and extramedullary(EM) devices (odds ratio [OR], 3.429; 95% confidence interval [CI], 0.632–18.877; p = 0.330).ConclusionIM nail breakage is a rare complication lack of time regularity and mostly occurs in unstable pertrochanteric fractures in the presence of delayed union/non-union. Osteosynthesis revision can be conduct by a new IM nail or EM device but considerable secondary failure rate is noteworthy. Self-dynamisation may be a warning sign of nail breakage.

Diagnostic Accuracy of Point-of-Care Tests Measuring Glycosylated Haemoglobin (HbA1c) for Glycemic Control: A Field Study in India.

ObjectivesThis study was performed to estimate diagnostic accuracy of the two commercially available point-of-care tests to identify poor glycemic control defined by HbA1c levels, with high-performance liquid chromatography (HPLC) as a reference.SettingsThe study was carried at two locations, general medical outpatient department of a teaching medical college in Bhopal (urban), and a primary health care centre in a rural area in the state of Madhya Pradesh, India.ParticipantsAll individuals with diabetes mellitus who presented to the health care facility for assessment of glycemic control. We compared HbA1c estimated from two index tests (Hemocue Hb 501, Sweden; SD Biosensor, South Korea) from capillary blood samples with HPLC performed from venous blood, as a reference standard.Primary and secondary outcome measuresDiagnostic properties of index tests such as sensitivity, specificity, positive and negative predictive value and diagnostic accuracy for identifying poor glycemic control were primary outcome measures. Lin’s concordance correlation coefficient (CCC) was secondary outcome measure.ResultsOut of 114 patients, all received reference standard - 103 patients received Hemocue A1C test and 110 patients received SD Biosensor test. Overall both the index tests had similar diagnostic accuracy estimates. The area under the Receiver Operating Curve for SDA1c device was 0.935 (95% CI 0.886-0.983), and for Hemocue device was 0.938 (95% CI 0.893-0.984). The Hemocue device HbA1c value of above 7.0 (positive) correctly predicted poor glycemic control 92% times (81.58% for SD device). There were 4 vs. 11 device failures and 14 vs. 12 failures with SD and Hemocue, respectively. Ambient air temperatures were no different for the device test failures.ConclusionsCommercially available point-of-care tests evaluated in this study are comparable and an acceptable alternative to HPLC-based measurements for the assessment of glycemic control. Tests and device failure rates of both the index tests are similar.

Transcatheter Aortic Valve Replacement for Bicuspid Aortic Valve Stenosis: A Practical Operative Overview.

The bicuspid aortic valve (BAV) represents a complex anatomic scenario for transcatheter aortic valve replacement (TAVR) because of its unique technical challenges. As TAVR is moving towards younger and lower-risk populations, the proportion of BAV patients undergoing TAVR is expected to rise. Initial experiences of TAVR with first-generation transcatheter heart valves in high surgical risk patients with BAV stenosis showed higher rates of device failure and periprocedural complications as compared to tricuspid anatomy. The subsequent advances in imaging techniques and understanding of BAV anatomy, new iterations of transcatheter heart valves, and growing operators' experience yielded better outcomes. However, in the lack of randomized trials and rigorous evidence, the field of TAVR in BAV has been driven by empirical observations, with wide variability in transcatheter heart valve sizing and implantation techniques across different centers and operators. Thus, in this review article, we provide a fully illustrated overview of operative periprocedural steps for TAVR in BAV stenosis, though recognizing that it still remains anecdotal.

A comparison of artificial urinary sphincter outcomes after primary implantation and first revision surgery

ObjectiveThe artificial urinary sphincter (AUS) is the gold standard for severe male stress urinary incontinence, though evaluations of specific predictors for device outcomes are sparse. We sought to compare outcomes between primary and revision AUS surgery for non-infectious failures. MethodsWe identified 2045 consecutive AUS surgeries at Mayo Clinic (Rochester, MN, USA) from 1983 to 2013. Of these, 1079 were primary AUS implantations and 281 were initial revision surgeries, which comprised our study group. Device survival rates, including overall and specific rates for device infection/erosion, urethral atrophy and mechanical failure, were compared between primary AUS placements versus revision surgeries. Patient follow-up was obtained through office examination, written correspondence, or telephone correspondence. ResultsDuring the study period, 1079 (79.3%) patients had a primary AUS placement and 281 (20.7%) patients underwent a first revision surgery for mechanical failure or urethral atrophy. Patients undergoing revision surgery were found to have adverse 1- and 5-year AUS device survival on Kaplan–Meier analysis, 90% vs. 85% and 74% vs. 61%, respectively (p<0.001). Specifically, revision surgery was associated with a significantly increased cumulative incidence of explantation for device infection/urethral erosion (4.2% vs. 7.5% at 1 year; p=0.02), with similar rates of repeat surgery for mechanical failure (p=0.43) and urethral atrophy (p=0.77). ConclusionsOur findings suggest a significantly higher rate of overall device failure following revision AUS surgery, which is likely secondary to an increased rate of infection/urethral erosion events.

Adaptive workload adjustment for cyber-physical systems using deep reinforcement learning

Reducing computational energy consumption in cyber-physical systems (CPSs) has attracted considerable attention in recent years. Associated with energy consumption is a heating of the devices. Device failure rate increases exponentially with increase temperature, so that high energy consumption leads to a significant shortening of processor lifetime.Reducing thermal stress without harming application safety and performance is the goal of this work. Our approach is to abort control tasks dispatch when this is judged, by a neural network, to not contribute to either safety or performance. This technique is orthogonal to others that have been used to reduce energy consumption such as dynamic voltage/frequency scaling and adaptive use of redundancy. Simulation experiments show that this approach leads to a further reduction in device aging when used in conjunction with these prior techniques.

Conversion from pegfilgrastim with on-body injector to pegfilgrastim-jmdb: cost-efficiency analysis and budget-neutral expanded access to prophylaxis and treatment

Aims Therapeutic guidelines recommend prophylaxis against chemotherapy-induced (febrile) neutropenia (CIN/FN). Pegfilgrastim (Neulasta), biosimilar pegfilgrastim-jmdb (Fulphila), and pegfilgrastim with on-body injector (OBI; Neulasta Onpro) are options for CIN/FN prophylaxis. We aimed to simulate the cost-savings and budget-neutral expanded access to CIN/FN prophylaxis or anticancer treatment achieved through conversion from pegfilgrastim-OBI to pegfilgrastim-jmdb and to evaluate the economic impact of FN-related hospitalization costs due to pegfilgrastim-OBI failure. Methods Cost-savings from conversion from pegfilgrastim-OBI to biosimilar pegfilgrastim-jmdb were simulated in a panel of 15,000 patients with cancer from the US payer perspective. The primary analyses included conversion rates of 10% to 100%. Adjusted analyses also considered OBI device failure rates of 1% to 7% and associated costs of FN-related hospitalization. Simulations of budget-neutral expanded access to prophylaxis with pegfilgrastim-jmdb or to rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) for diffuse large B-cell lymphoma (DLBCL) were also performed. Results In a 15,000-patient panel, conversion from pegfilgrastim-OBI to pegfilgrastim-jmdb resulted in cost-savings ranging from $481,259 (10% conversion) to $4,812,585 (100% conversion) in a single cycle. Over 6 cycles at 100% conversion, savings were $28,857,510 and could provide 9,191 additional doses of pegfilgrastim-jmdb or 4,463 cycles of R-CHOP to patients with DLBCL. Adjusted for OBI failure, cost-savings over 6 cycles ranged from $2,935,565 (10% conversion; pegfilgrastim-OBI failure rate of 1%) to $32,236,499 (100% conversion; 7% failure). These cost-savings could provide 943 doses of pegfilgrastim-jmdb or 454 doses of R-CHOP (10% conversion; 1% pegfilgrastim-OBI failure) or provide 10,261 doses of pegfilgrastim-jmdb or 4,982 cycles of R-CHOP (100% conversion; 7% failure). Conclusion Conversion from pegfilgrastim to pegfilgrastim-jmdb is associated with significant cost-savings which increase markedly when also accounting for pegfilgrastim-OBI failure and associated FN-related hospitalizations. These general and failure-related cost-savings could be allocated on a budget-neutral basis to provide more patients with additional CIN/FN prophylaxis or antineoplastic treatment.

Femoral artery access site closure with perclose suture mediated device in coronary interventions

ObjectiveTo compare the outcome of suture mediated vascular closure device Perclose Proglide (PP) with manual compression (MC) following transfemoral access for coronary interventions (CI). MethodsIt is a retrospective, observational, single centre study from January 2018 to September 2019. Consecutive patients undergoing interventions through transfemoral access were divided into PP and MC groups. Those with less than 3 months follow up were excluded. Two groups were compared for baseline characteristics and various complications at 24 h and at 30 days. ResultsOut of 1743 patients studied, PP group included 1343 and MC group, 400 patients. Both groups were comparable in baseline characteristics, sheath size and use of antiplatelets and anticoagulation. PP group had significantly less minor bleeding (P = .01, CI 0.34–4.03) and hematoma (P = .0007, CI 0.95–5.10) at 24 h. At 30 days, minor bleeding (P < .0001, CI 0.97–4.25), hematoma (P = .0002, CI 1.05–4.93) and pseudo-aneurysm (P = .0095, CI 0.03–1.18) were also significantly less in PP group. Obesity (OR 3.5, CI 1.29–9.49) and hypertension (OR 2.41, CI 1.12–5.19) were associated with increased minor bleeding at 24 h. Device failure rate was 2.38%. ConclusionsPP device is safe, effective and is associated with fewer complications than MC in CI. Device failure rate is low. Obesity and hypertension are associated with increased minor bleeding in both groups.

Conversion to Biosimilar Pegfilgrastim-Jmdb from Pegfilgrastim with on-Body Injector Device in Diffuse Large B-Cell Lymphoma: Simulation Modeling of Cost-Savings and Budget-Neutral Expanded Access to Prophylaxis and Anti-Neoplastic Therapy Considering Device Failure Rate

Introduction: Approvals of biosimilar pegfilgrastim products in recent years have reduced the costs of single-dose prophylaxis of chemotherapy-induced (febrile) neutropenia (CIN/FN). While reference pegfilgrastim with on-body injector (PEG-OBI) offers convenience to patients over use of next day pre-filled syringe (PFS), PEG-OBI has a reported failure rate of 1.7-6.9% that predisposes patients to increased risk of CIN/FN episodes. Incremental FN-related hospitalizations (FN-HOSP) associated with PEG-OBI failure contribute to the cost differential between PEG-OBI and assured prophylaxis with biosimilar PEG-PFS. Cost savings generated from conversion to biosimilar PEG-jmdb create opportunities for providing expanded access on a budget-neutral basis to additional CIN/FN prophylaxis or anti-neoplastic treatment. Hence, in a panel of 15,000 patients with diffuse large B-cell lymphoma (DLBCL), we aimed to: 1) quantify the cost-savings from assured prophylaxis with biosimilar PEG-jmdb over PEG-OBI accounting for device failures, 2) simulate the additional CIN/FN prophylaxis that could be achieved from the cost-savings, and 3) model the expanded access to anti-neoplastic treatment with rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) that could be provided on a budget-neutral basis through reallocation of cost-savings. Methods: Simulation analysis in a panel of 15,000 DLBCL patients at risk for CIN/FN from the US payer perspective utilized. Costs of medication were based on Q1 2020 average selling price (ASP) for PEG-OBI, PEG-jmdb, and R-CHOP drugs derived from CMS Q3 2020 reimbursement limits; cost of PEG-OBI and PEG-jmdb administration per CMS Outpatient Prospective Payment System; between one and six cycles of prophylaxis; conversion rates from PEG-OBI to biosimilar PEG-jmdb ranging from 10% to 100%; and PEG-OBI failure rates of 1% to 7%. Differential base rate of FN-HOSP in NHL (rate of FN-HOSP without colony-stimulating factor [CSF] minus rate with CSF) was 10.03% over a 6-cycle regimen with 56% occurring in cycle 1 (Chrischilles et al., Cancer Control 2002; 13.25% with CSF, 23.28% without). FN-HOSP costs in 2012 of $25,676 per episode for NHL patients (Tai, J Oncol Pract 2017) were adjusted per the Consumer Price Index for Medical Care to $31,914 for 2020. Results: Conversion from PEG-OBI to biosimilar PEG-jmdb in a panel of 15,000 DLBCL patients generated savings ranging from $379,230 (for one cycle of prophylaxis at 10% conversion) to $22,753,800 (6 cycles at 100%) considering the cost of medication plus administration. These cost-savings could provide access to between 110 (1 cycle at 10% conversion) and 6,623 (6 cycles at 100%) additional cycles of PEG-jmdb on a budget-neutral basis, or between 58 and 3,452 cycles of R-CHOP, respectively. Taking incremental FN-HOSP costs due to PEG-OBI failure into consideration, cost-savings in cycle one from conversion to PEG-jmdb, ranged from $406,118 (at 10% conversion and PEG-OBI failure of 1%) to $5,674,454 (at 100% conversion and 7% PEG-OBI failure). These savings translated into expanded access to between 118 additional cycles of PEG-jmdb or 62 cycles of R-CHOP (at 10% conversion and 1% PEG-OBI failure) and 1,652 cycles of PEG-jmdb or 861 cycles of R-CHOP (at 100% conversion and 7% PEG-OBI failure). Over a 6-cycle regimen, savings increase to $2,323,394 (at 10% conversion and 1% PEG-OBI failure) to $26,114,789 (at 100% conversion and 7% PEG-OBI failure). These additional savings increased expanded access to PEG-jmdb to between 676 additional cycles of PEG-jmdb or 353 cycles of R-CHOP (at 10% conversion and 1% PEG-OBI failure) and 7,601 cycles of PEG-jmdb or 3,962 cycles of R-CHOP (at 100% conversion and 7% PEG-OBI failure). Conclusions: CIN/FN prophylaxis with biosimilar PEG-jmdb generates substantial cost savings compared to PEG-OBI when considering drug and administration costs. Savings further increase when the costs of FN-HOSP related to PEG-OBI failure are taken into account. Reallocation of savings realized through conversion to biosimilar pegfilgrastim-jmdb provide expanded access to additional CIN/FN prophylaxis and anti-neoplastic treatment on a budget-neutral basis while reducing risk and associated hospitalization costs associated with inadequate prophylaxis due to device failure. Disclosures McBride: Coherus BioSciences: Consultancy, Speakers Bureau; Merck: Speakers Bureau; Pfizer: Consultancy; Sandoz: Consultancy; MorphoSys: Consultancy; Bristol-Myers Squibb: Consultancy. MacDonald:Sandoz: Consultancy; Coherus BioSciences: Research Funding; Mylan: Consultancy; Novartis: Consultancy; Janssen: Consultancy; Rockwell Medical: Consultancy; Terumo: Consultancy; Celgene: Consultancy; MorphoSys: Consultancy. Abraham:Sandoz: Consultancy; Mylan: Consultancy; Janssen: Consultancy; Rockwell Medical: Consultancy; Terumo: Consultancy; Celgene: Consultancy; Coherus BioSciences: Research Funding, Speakers Bureau; MorphoSys: Consultancy.

Accelerated Stress Tests and Statistical Reliability Analysis of Metal-Oxide/GaN Nanostructured Sensor Devices

In this work, sensor die/process and packaging reliabilities of metal-oxide/GaN nanowire-based gas sensors have been studied for the first time, using industry standard accelerated lifetime tests, such as- High Temperature Operating Life, High Temperature Storage Life, Temperature Cycling Test and Highly Accelerated Stress Test. The metal-oxide functionalization used for sensing ethanol exposure in this study is ZnO. For all the tests, sample ZnO/GaN devices have been exposed to 500 ppm of ethanol in dry air at room temperature (20°C) to observe and record the degradation of signal to noise ratio (SNR) as a function of stress time and number of thermal cycles. Although no complete device failure was observed in any of the performed tests, gas sensing response kept decreasing gradually due to increasing stress. The lowering of the sensor response is believed to be due to gradual phase transformation of the receptor ZnO and baseline resistance increase. The method for estimating failure rate and lifetime of sensor devices has been discussed in detail. Using statistical data from the performed accelerated stress tests, chi-square distribution has been implemented to predict the failure rate and lifetime of GaN nanostructured sensor devices. The mean-time-to-failure (MTTF) of the stressed devices of this study is about 4 years.

Influence of abrasive morphology and size dispersity of Cu barrier metal slurry on removal rates and wafer surface quality in chemical mechanical planarization

Chemical mechanical planarization (CMP) is widely used in the fabrication of semiconductor devices to achieve global planarization. The overall CMP performance is affected by material removal rates. Defects and dishing generated on wafers during CMP increase device failure rate. In the present study, we examined the effect of silica abrasive morphology and size dispersity on removal rates and surface morphologies of wafers. The slurry composed of polydispersed irregular silica (PI) showed the highest overall removal rates (for interconnection, barrier, and dielectric materials), although the removal rate of the slurry consisting of polydispersed spheric silica for the interconnection material (Cu) was higher than that of PI. The overall removal rate increased with increasing silica concentration. The lowest surface roughness was achieved by polydispersed irregular abrasives. The surface roughness increased by increasing the concentration of abrasives. The polydispersed irregular abrasives also allowed for the lowest defects. Small dishing values were observed for the slurry systems manufactured in this study, indicating that the abrasive morphology seldom influenced the dishing behaviors. The understanding of morphology and size dispersity can be beneficial to CMP global planarization with high removal rates and low defects.

Reliability Impact Analysis of Fault Current Limiters of Distribution Network Under Protection Miscoordination Due to Distributed Generations

Despite distributed generations (DGs) advantages, the presence of them can cause glitches in distribution networks. One of the typical glitches is a mismatched fuse and recloser in temporary short circuits, which is often remedied by fault current limiter (FCL). By calculating the expected benefits to distribution companies (DISCOs) in various value of loss load scenarios, once the uncertainty output of DGs is considered, this paper examines the effectiveness of FCLs in solving drawbacks and improving reliability. FCL can improve network reliability in one of two ways: a) the FCL can reduce the magnitude of fault current, thereby decreasing the failure rate of protective devices, b) the FCL can correct a mismatched fuse and recloser, resulting in a lower energy not supplied (ENS) rate. The present paper uses the biogeography-based optimization method to measure optimal FCL impedance in terms of maximizing the DISCO’s benefit after FCL installation. Using simulated performance on a test distribution system, FCL network penetration is founded to resolve the identified problem by improving the ENS rate.

Mission profiles and hygrothermal conditions: Its effects on the reliability of a soft switching converter

Reliability predictions are routinely performed according to mission profiles, in photovoltaic applications including at least irradiance and temperature. This paper is aimed at assessing the necessity of including humidity meteorological data in the mission profile. A DC/DC soft-switching converter rated at 1 kW, and aimed at PV applications is selected as case study. Its reliability is predicted using FIDES guide, using seasonal mission profiles for eight different sites with climates ranging from tropical-humid to hot and dry. The prediction results are contrasted, assuming that the most failure-prone converters are those at the highest temperature. The results corroborate that the thermal stress factor has a large impact on the increase in the failure rate of semiconductor devices. Nevertheless, humidity also has a noticeable impact on the failure rate, contributing with 30% in the transistors, with 6% in the diodes, and in minor proportion in the passive devices. The impact of humidity is larger when it occurs simultaneously with sustained, high temperatures, and it was found that neglecting humidity might underestimate the failure rate by as much as 35% in hot, humid sites. Therefore, detailed humidity meteorological data should be included in the mission profile.

A Comparison of Bipolar Hemiarthroplasty versus Dynamic Hip Screw Fixation of Basicervical Femoral Neck Fractures

Background: Surgical treatment of basicervical femoral neck fractures, which are biomechanically similar to intertrochanteric fractures, is an internal fixation by dynamic hip screw (DHS) and anti-rotation screw. Since one of the remarkable complications of this surgical procedure is device failure, we aimed to make a comparison between bipolar hemiarthroplasty and the DHS plate fixation in elderly patients with basicervical femoral neck fracture. Methods: In this randomized controlled clinical trial study, 60 patients with femoral neck fractures were randomly divided into two groups of DHS fixation (control group, n = 30) and bipolar hemiarthroplasty (intervention group, n = 30). Harris Hip Score (HHS) questionnaire and the Visual Analogue Scale (VAS) for pain assessment were used for functional evaluations. Postoperative complications were evaluated at 6 months and one year postoperatively. Results: The mean age was 73.95 ± 9.85 years in the hemiarthroplasty group and 74.22 ± 7.85 years in the internal fixation group. Three patients in the internal fixation group and 6 patients in the hemiarthroplasty group were excluded. HHS in 6 months and one year after surgery in the intervention group was dramatically higher than the control group. There were no noticeable changes in VAS scores between the two groups. Two cases of device failure happened in the control group. Conclusions: It seems that bipolar hemiarthroplasty is more effective than internal fixation by DHS plate in improving the patient’s quality of life, considering higher HHS scores, earlier patient mobilization, shorter hospital stay, lower device failure rate, and lower revision rate

Ultrasound-detected venous changes associated with peripheral intravenous placement in children.

Ultrasound shows several venous changes in pediatric PIV-containing veins. Changes were visualized by ultrasound in the absence of physical exam findings. Venous luminal narrowing, wall thickening, and thrombosis may explain PIV failure. Peripheral intravenous catheters (PIVs) are routinely used for venous access in hospitalized pediatric patients to administer fluids and medications and to aspirate blood. Unfortunately, PIVs do not remain functional for the entire duration of intravascular need. We hypothesized that PIV malfunction may be related to venous changes that can be visualized with ultrasound (US) imaging. The purpose of this study was to describe and document such changes in pediatric patients. This Institutional Review Board-approved study was performed at a tertiary pediatric medical center. Patients underwent US scans of their PIV-containing veins, documenting venous characteristics such as depth, diameter, wall thickness, blood flow, valves, branch points, and presence of thrombus. Patient demographics and PIV characteristics were also recorded. Data from 30 patients including 12 males and 18 females with a mean age of 11 years were analyzed. Mean venous depth and diameter were 2.07 ± 0.13 and 2.02 ± 0.18 mm, respectively. Mean PIV dwell time at time of evaluation was 3.3 days. PIV-associated venous changes were seen in 73% of accessed veins and included lumen narrowing (47%), wall thickening (33%), presence of thrombus (20%), and absence of blood flow around the PIV tip (40%). PIV-associated venous changes are seen with US in the majority of pediatric patients with indwelling PIVs but are not necessarily appreciated on physical exam. These changes may help explain the high rate of pediatric PIV device failure. Given the small sample size, further investigation is needed to better characterize PIV-associated venous changes in children.

Causes and frequency of cochlear explantation

Background: The cochlear implant (CI) is unique among medical devices in that it serves as a neurosensory prosthesis capable of restoring or providing de novo the sense of hearing to its users. Causes of cochlear device explantation are divided primarily into device failures and medical failures. Study design: Retrospective and prospective analysis. Objective: determine the causes and the frequency of device and medical failure. Patients and Methods: The study involve 17 patients who had cochlear explantation from total implantation 766 patients in the department of otolaryngology in AL-Yarmouk teaching hospital during period from April 2008 to March 2018, and the data was collected from operative notes that is documented in patients files. Results: A total of 766 implants were performed from April 2008 to March 2018, with 17 devices explanted, the implanted devices were 45.8% Cochlear nucleus devices, and 27.5% were MED-EL devices and 26.6%. Where Advance bionics. The overall failure rate was 17 of 766 (2.22%) of which 13 (76.47%)due to medical failures and 4 (23.5%) due to device failures. Patients with cochlear nucleus devices underwent 9 explants (2.56% failure rate) of which 8 (88.9%) was medical failures and 1(11.1%) was device failures. Patients with MED-EL underwent 3 explants (1.42% failure rate), which all of them was due to device failures Patients with advance bionics underwent 5 explants (2.45% failure rate) all of them was medical failure. Medical failures included wound infection with wound breakdown, wound infection with flap necrosis, hematoma, cholesteatoma and biofilm. Device failure include hard failure and soft failure. Over all the average time to explantation was 559days (range, 10-3468 days). Conclusion: Overall, cochlear explantation rate is low. The medical causes was more common and more with cochlear nucleus device type. the device failure rate was more common with MED-EL device type.

Evaluating Reasons for Revision Surgery and Device Failure Rates in Patients Who Underwent Cochlear Implantation Surgery

Understanding the reasons for cochlear implant (CI) revision surgery and device failure rates is important for clinicians when counseling patients who are considering CI. To analyze the revision surgery rate, reasons for revision surgery, and device failure and survival rates of different device models in recipients of CIs. In this cohort study, cochlear implants at Samsung Medical Center, a tertiary referral center, were retrospectively reviewed. Patients who underwent CI surgery from October 2001 to March 2019 were included. In the device survival analysis, the first revision surgery was considered the primary event, and the end point of observation was June 1, 2019. Therapeutic and rehabilitative CI surgery. The revision surgery rate, reasons for revision surgery, and the failure and survival rates of different device models were analyzed. The Kaplan-Meier method and the log-rank test were used to present both the device survival and cumulative survival curves with rates. In this study, 43 of 925 patients with CIs (4.6%) underwent a revision surgery. Device failure was the most common reason (28 of 43 patients [65%]). Flap-associated problems and migration of the inner device were the next most important reasons (4 of 43 [9.3%] each). Overall, the 10-year cumulative survival rate of CI surgery was 94.4%, and the device survival rate was 96.0%. Thirteen different CI devices from 4 different manufacturers were implanted, and no meaningful differences in device failure were found among CI manufacturers or devices (hazard ratios for cumulative survival: Cochlear, 1.67 [95% CI, 0.72-3.88]; Advanced Bionics, 1.67 [95% CI, 0.61-4.53]; Med-El, reference; hazard ratios for device survival: Cochlear, 1.65 [95% CI, 0.55-4.99]; Advanced Bionics, 1.93 [95% CI, 0.56-6.74]; Med-El, reference). Several recalls were issued by manufacturers during the study period, and after excluding the recalled devices, the device survival rates for 5, 10, and 15 years were 98.2%, 97.7%, and 94.9%, respectively. Generally, implanted devices remain safe and stable for a long time, and no significant differences in survival rates were found between device types or manufacturers. Device failure was the main reason for CI revision, followed by flap-associated problems and migration of the inner device.

Medium-Term Bioresorbable Scaffold Outcomes Utilising Data From an Australian Clinical Quality Registry

Bioresorbable scaffolds (BRS) are a novel technology in coronary intervention. However, recent trials demonstrate higher rates of device failure compared to contemporary drug-eluting stents. This study sought to utilise a clinical quality registry to assess the medium-term safety of the Abbott Absorb BRS (Abbott Vascular, Santa Clara, CA, USA), in an Australian context. A prospective, observational study of 192 BRS percutaneous coronary interventions (PCI) compared to 31,773 non-BRS PCIs entered in the Victorian Cardiac Outcomes Registry from 2013 to 2017. The main outcome measure was patient-oriented composite endpoint (POCE) events comprising all-cause mortality, any myocardial infarction (MI), and any revascularisation. Bioresorbable scaffolds patients (mean age 61.6±10.5 years, 79% male) were younger, had less comorbidity, less prior PCI, fewer ST elevation myocardial infarction (STEMI) presentations, lower rates of multi-lesion disease and more adjuvant devices compared to non-BRS PCI (all p<0.01). All-cause mortality was 2.1%, myocardial infarction (MI) 2.1%, scaffold thrombosis 3.1% and any revascularisation 14.1% (mean follow-up 27.4±8.9 months). POCE events occurred in 11.5% at 1 year and 16.9% at 2 years, comparable to pooled-trial data. Multivariate predictors of POCE were >1 scaffold used (odds ratio [OR] 4.6, 95% confidence interval [CI] 1.9-11.4, p<0.01) and scaffold diameter ≤2.5 mm (OR 3.3, 95% CI 1.4-7.6, p=0.02). Over 95% guideline adherence was achieved in six of eight patient selection criteria and four of six device deployment criteria. In an Australian setting, BRS were used in non-complex patients. Most guidelines for use were adhered to and outcomes were comparable to pooled trial data. Clinical quality registries are effective in assessing novel treatments and technologies when potential safety concerns develop.

Outcomes of Expandable Prostheses for Primary Bone Malignancies in Skeletally Immature Patients: A Systematic Review and Pooled Data Analysis.

Osteosarcoma and other primary bone malignancies are relatively common in skeletally immature patients. Current literature features case series with disparate complication rates, making it difficult for surgeons to educate patients on outcomes after limb salvage with expandable prostheses. This study aims to provide an update on complication rates, mortality, and functional outcomes in patients who undergo limb salvage with expandable prostheses for primary bone malignancies. A systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. An exhaustive PubMed/Medline and Cochrane search of peer-reviewed published literature from 1997 to 2017 was performed, yielding a total of 1350 studies. After multiple rounds of review for inclusion and exclusion criteria, 28 retrospective studies were included. All were level IV evidence of case series and retrospective studies. Overall, this included 634 total patients and 292 patients with individual patient data. The primary outcomes studied were complication rates, mortality, and Musculoskeletal Tumor Society (MSTS) functional score. Secondary outcomes included complication rate subtypes, number of lengthening procedures, mean amount lengthened, and prevalence of limb length discrepancies. A total of 292 patients with individual patient data averaged 10.1 years at the surgery and had a mean follow-up of 67 months. Two hundred sixteen patients (74%) had tumors of the distal femur. MSTS scores averaged 80.3 and overall mortality was 22%. Patients with distal femur tumors averaged 4.4 lengthening procedures and 43 mm lengthened. Leg length discrepancy (LLD) was 36% overall, which increased with longer periods of follow-up (P<0.001). Overall complication and revision rate was 43%, increasing to 59% in patients with 5 to 10 years of follow-up, and 89% in patients with >10 years of follow-up. Minimally invasive prostheses had lower rates of complications than noninvasive prostheses (P=0.024), specifically mechanical complications (P=0.028), mostly because of increased rates of lengthening and device failure in the noninvasive models (21% vs. 4%, P=0.0004). Despite its limitations, which include entirely heterogenous and retrospective case series data, this systematic review provides clinicians with pooled summary data representing the largest summary of outcomes after reconstruction with expandable prostheses to date. This analysis can assist surgeons to better understand and educate their patients and their families on functional outcomes, mortality, and complication rates after limb-sparing reconstruction with expandable prostheses for primary bone malignancies. Level IV-retrospective case series with pooled data.

P1676De novo aortic insufficiency following long term LVAD support can be successfully treated with TAVI and a pre-stenting technique

Abstract Background/Introduction Long-term continuous flow left ventricular assist device (cf-LVAD) can result in the development of relevant aortic regurgitation (AR). Although its impact on survival is still controversial, it causes heart failure related symptoms. Current evidence for less invasive strategies to treat AR in cf-LVAD patients is limited. Purpose This study sought to investigate the value of transcatheter aortic valve implantation (TAVI) to treat severe de novo AR in patients on long-term cf-LVAD support. Methods We performed a retrospective analysis of 13 patients with severe AR following cf-LVAD implantation treated with TAVI between 2010 and 2019. TAVI's were performed via transfemoral (n=11), transapical (n=1) and transaxillary (n=1) access route. CoreValve (n=2), LotusValve (n=1), SapienXT (n=1) and Sapien3 (n=9) were used as transcatheter heart valves. In 4 patients, a new off-label strategy using landing-zone pre-stenting with a Sinus-XL stent was used (Figure 1). Results The median time interval from LVAD-implantation to TAVI was 1.7 years [interquartile range (IQR): 1.0 - 3.1]. Median age was 62 years [IQR: 57 - 67]. No procedural mortality or stroke was observed. Overall, device success according to VARC-II criteria was low due to a high rate of second valve necessity (54%). In contrast to the standard implantation technique, device success was 100% when the newly developed pre-stenting technique was applied (Table 1). Aortic regurgitation at discharge was none/trace in all patients. Valve function remained stable in all patients during a median echocardiographic follow-up time of 105 days [IQR: 11 - 298]. Table 1 Overall Sinus-XL prestenting (n=4) NO prestenting (n=9) Device success 7 (54) 4 (100) 3 (33) Procedural mortality 0 (0) 0 (0) 0 (0) Correct positioning of a single valve 7 (54) 4 (100) 3 (33) Intended valve performance 13 (100) 4 (100) 9 (100) Moderate or severe aortic regurgitation 0 (0) 0 (0) 0 (0) Figure 1 Conclusions Transcatheter aortic valve implantation is an efficient tool to treat cf-LVAD induced severe AR. The challenging anatomy of the non-calcified device landing zone causes a relatively high rate of primary device failure, which could be overcome with a pre-stenting technique. Acknowledgement/Funding None

Twenty years of experience in revision cochlear implant surgery: signs that indicate the need for revision surgery to audiologists.

To report device failures, audiological signs and other reasons for revision cochlear implant surgery, and discuss indications for revision surgery. Revision procedures between November 1997 and August 2017 were retrospectively analysed. Over 20 years, 2181 cochlear implant operations were performed, and 114 patients underwent 127 revision operations. The revision rate was 4.67 per cent. The full insertion rate for revision cochlear implant surgery was 88.2 per cent. The most frequent reasons for revision surgery were: device failure (59 per cent), wound breakdown (9.4 per cent) and electrode malposition (8.7 per cent). The device failure rate was: 2.78 per cent for Advanced Bionics, 1.82 per cent for Cochlear and 5.25 per cent for Med-El systems. The number of active electrodes was significantly increased only for Med-El devices after revision surgery. The most common complaints among 61 patients were: gradually decreased auditory performance, sudden internal device shutdown and headaches. The most common reason for revision surgery was device failure. Patients should be evaluated for device failure in cases of: no hearing despite appropriate follow up, side effects such as facial nerve stimulation, and rejection of speech processor use in paediatrics. After revision surgery, most patients have successful outcomes.