Efficacy Of Device Research Articles

Hemodynamic Support with Intra Aortic Balloon Pump Differs by Etiology of Cardiogenic Shock

Purpose While intra-aortic balloon pump (IABP) counterpulsation has not been shown to be of benefit in patients with acute myocardial infarction (AMI) with cardiogenic shock (CS), emerging data suggest that patients with acute decompensated heart failure (ADHF) might be more likely to stabilize with this device. Methods Patients with hemodynamic evidence of CS related to either AMI or ADHF who received IABP support were studied retrospectively. Cardiac outputs (CO) and indices (CI) were calculated using the Fick method. Hemodynamics were compared before and after IABP insertion and between the AMI and ADHF cohorts. Results During the study period, 77 patients were supported with IABP for AMI related CS while 132 were supported for ADHF related CS. The mean age was 64.7±13.6 years and 75.1% were men. Mean arterial blood pressure was 75.6±10.6mmHg and 78.4±14.6mmHg among ADHF and AMI patients, respectively (p=0.12). Mean pulmonary artery pressure was higher among those with ADHF (37.9±9.3mmHg vs 33.6±8.9mmHg, p=0.002). Left ventricular ejection fraction was 18.0±8.9% among those with ADHF and 28.9±12.0% among those with AMI (p Conclusion While the degree of hemodynamic compromise was similar between those with CS related to AMI and ADHF, the response to IABP counterpulsation differed significantly between these cohorts suggesting that the device's efficacy may differ between etiologies of CS.

An Innovative Advance in Non-invasive Wound Closure: A New Paradigm.

Injury is the leading health and readiness threat to the armed forces, with two million instances per year; therefore, innovating wound care solutions can help improve readiness. The DermaClip Skin Closure Device is a new, non-invasive, painless, and easy-to-apply wound closure device that does not require either needles or painful anesthesia injections or create additional damage to the wounded area. The efficacy of the device was tested in a 120-patient trial, composed of 60 experimental cases and 60 control cases. The trial of the DermaClip device demonstrated the device's efficacy in meeting the needs of clinical applications. Additionally, the experimental group had no adverse events in the product safety test. The efficacy of the device coupled with the features of ease of use and limited requirements for application make this a wound closure device particularly applicable to the emergency and battlefield setting.

Treatment of FBSS Low Back Pain with a Novel Percutaneous DRG Wireless Stimulator: Pilot and Feasibility Study.

Test a miniaturized neurostimulator transforaminally placed at the dorsal root ganglion (DRG) and evaluate the device's safety and efficacy in treating failed back surgery syndrome (FBSS) low back pain. Pilot, two-phase study. Eleven subjects with chronic intractable neuropathic trunk and/or lower limbs pain were included. The system consisted of an implantable, miniaturized stimulator, provided by Stimwave Technologies (Freedom-4) and an external transmitter. Only one stimulator per subject was implanted unilaterally and transforaminally at L1 to L5 levels. During Phase 1 of the study, the stimulators were not anchored. In Phase 2, the stimulators were anchored. Subjects were treated during 45 days after which the stimulator was removed. Pain reduction, implant duration, and stimulator migration were registered. Overall pain reduction was 59.9%, with only one device placed at one location, covering only a portion of the painful areas in the majority of the subjects. In Phase 1, the non-anchored stimulators migrated a mean of 8.80 mm and in Phase 2 a mean of 1.83 mm. Stimulator migration did not correlate with changes in pain relief. Mean time-to-implant duration was 10 minutes and no adverse events were reported during implant, follow-up period, or after explant. The pain reduction results indicate that the Freedom-4 spinal cord stimulation (SCS) Wireless System is a viable treatment of low back pain through stimulation of the DRG, and better overall pain reduction may be achieved by implanting multiple devices. With short percutaneous implant times and excellent safety profile, this new system may offer health cost savings.

Valid randomization-based p-values for partially post hoc subgroup analyses.

By 'partially post-hoc' subgroup analyses, we mean analyses that compare existing data from a randomized experiment-from which a subgroup specification is derived-to new, subgroup-only experimental data. We describe a motivating example in which partially post hoc subgroup analyses instigated statistical debate about a medical device's efficacy. We clarify the source of such analyses' invalidity and then propose a randomization-based approach for generating valid posterior predictive p-values for such partially post hoc subgroups. Lastly, we investigate the approach's operating characteristics in a simple illustrative setting through a series of simulations, showing that it can have desirable properties under both null and alternative hypotheses.

What's the difference? Learning collaboratively using iPads in conventional classrooms

Since its release in 2010, Apple's iPad has attracted much attention as an affordable and flexible learning tool for all levels of education. A number of trials have been undertaken exploring the device's efficacy for specific purposes, such as improving delivery of course content and learning resources at tertiary level, and the performance of apps for meeting specialised learning needs. However, with increased mainstreaming of these devices through iPad-supported modern learning environment (MLE) and Bring Your Own Device (BYOD) programmes, data are becoming available that provides insight into how these devices function as part of regular classroom environments. This article reports an analysis of data collected over almost 3 years from nearly 100 New Zealand primary (elementary) students of different ages, who used iPads daily for most curriculum tasks. Specifically, it uses different data sources to explore how observed and recorded device design and app attributes, affected the students' ability to work collaboratively.Results suggest fundamental differences exist between iPads and other digital devices that helped these students collaborate, and that when combined with cloud-based apps and services such as Google Docs, extended this collaboration to much wider audiences well beyond the school gate. It concludes that beyond the hype and rhetoric, exciting potential exists for this tool to support a ‘blurring in the line’ between learning in formal school and informal environments.

Electrical bioimpedance measurement as a tool for dysphagia visualisation.

A non-invasive and portable bioimpedance method and a device for detecting superior to inferior closure of the pharynx during swallowing have been developed. The 2-channel device measures electric impedance across the neck at two levels of the pharynx via injected currents at 40 and 70 kHz. The device has been trialled on both healthy and dysphagic subjects. Results from these trials revealed a relationship (r = 0.59) between the temporal separation of the second peaks in the bioimpedance waveforms and descending pressure sequence in the pharynx as measured by pharyngeal manometry. However, these features were only clearly visible in the bioimpedance waveforms for 64% of swallows. Further research is underway to improve the bioimpedance measurement reliability and validate waveform feature correlation to swallowing to maximise the device's efficacy in dysphagia rehabilitation.

Tratamento percutâneo do canal arterial com a prótese Amplatzer Duct Occluder II (ADO II): nova opção para um antigo defeito

INTRODUÇÃO: Nos últimos 30 anos, vários dispositivos têm sido utilizados para o fechamento percutâneo dos canais arteriais patentes. O Amplatzer Duct Occluder II (ADO II) foi desenvolvido para atender aos canais pequenos e moderados, com duplo disco e menor perfil, simplificando o implante sem perder a eficácia e a segurança. O objetivo deste estudo é discutir aspectos técnicos do uso da nova prótese e apresentar a experiência do grupo no uso desse dispositivo MÉTODO: Análise dos registros de pacientes portadores de canal arterial patente submetidos a fechamento percutâneo com a prótese ADO II, no período de setembro de 2009 a março de 2010, identificados por ecocardiogramas transtorácicos RESULTADOS: Foram selecionados 8 pacientes. Os pesos variaram de 8 kg a 78 kg (38,8 ±24,1 kg). Quatro canais eram do tipo E, três eram do tipo A, e um, do tipo C. O implante foi possível em todos os casos. As próteses utilizadas foram 5-6 em três casos, 5-4 em dois casos, e 4-6, 6-4 e 6-6 uma vez cada. Apenas um caso apresentou fluxo residual, sem jato, imediatamente após o fechamento, que desapareceu no primeiro ecocardiograma transtorácico de controle na primeira semana de seguimento. Não houve óbito ou complicações em nenhum caso CONCLUSÃO: A prótese ADO II mostrou-se segura e eficaz, mesmo em lactentes. A abordagem retrógrada torna o procedimento mais rápido e fácil. As taxas de oclusão são comparáveis às do ADO I. Estudos com maior número de pacientes e seguimento mais longo são necessários para estabelecer a segurança e a eficácia do dispositivo em crianças menores.

Understanding Cost Effectiveness: Money Matters?

Economic analysis is an important component that should be implemented when evaluating a new medical device. A new medical device should be both effective in improving patient outcomes as well as cost effective before it is implemented into clinical practice. This paper begins with an overview on the different methods of economic analysis including cost-minimization analysis, cost-effectiveness analysis, cost-utility analysis, and cost-benefit analysis. The second section provides a description of key design issues in cost-effectiveness analyses that are relevant to medical device trials including the perspective of the economic evaluation, the collection of cost data, how to establish clinical effectiveness in an economic analysis, how to conduct a sensitivity analysis, and when it is necessary to discount costs. It is important and necessary to consult with a health economist to ensure that the appropriate methodology is followed when conducting an economic evaluation. In conclusion, since most jurisdictions have limited funding available for health care, money definitely matters. If the cost of a medical device is unreasonable or if funding is not available, it will likely not be able to be implemented, regardless of its effectiveness. A well-conducted economic analysis will be able to answer questions on the medical device's efficacy and cost effectiveness.

Grasping The Role Of Technology: A Conversation With Ron Dollens

In an interview with Health Affairs founding editor John Iglehart, Ron Dollens outlines the differences between drug and device companies in the current U.S. health care marketplace. He discusses at length the recent Medicare coverage decision regarding implantable cardiac defibrillators, one of his company's major innovations. He sees a growing trend for cost-effectiveness to be considered along with a device's safety and efficacy, and he finds this to be appropriate in an environment characterized by constrained resources. He believes that the United States must find a solution to the problem of uninsurance, if our health care system is to remain competitive in a global economy.

Medical Device Review at the Food and Drug Administration: Lessons from Magnetic Resonance Spectroscopy and Biliary Lithotripsy

Medical devices marketed in the United States must satisfy FDA standards of safety and effectiveness. Many observers have criticized the FDA medical device review process as both time consuming and unpredictable. In this note, Lawrence Makow examines the Agency's treatment of two novel medical technologies, magnetic resonance spectroscopy and biliary extracorporeal shockwave lithotripsy. He concludes that the outcomes of these cases exemplify the mismatch between clinical utility and FDA approval status that has prompted concerns about lack of predictability. Mr. Makow asserts that this mismatch results from the FDA's implementation of the medical device statute rather than from the statute itself. He proposes an asymmetric standard for evaluating the safety and efficacy of new medical devices. While the safety showing would always require a high burden of proof, the efficacy standard would vary depending on the relationship between the device's safety and efficacy. Under this asymmetric standard, the FDA could better manage its workload and achieve more predictable results without sacrificing the public interest in avoiding injury from unproven medical devices.

Cardiosynchronous limb compression: effects on noninvasive vascular tests and clinical course of the ischemic limb.

Some patients with chronic arterial obstruction of the limbs may still suffer the consequences of advanced tissue ischemia, including ulceration and rest pain, and face threatened limb loss in spite of available surgical, pharmacologic, and other treatments. Additional therapeutic modalities were thus sought to accomplish limb salvage. A literature review indicated that most reports on R-wave-triggered circumferential limb compression (cardiosynchronous limb compression [CSC]) demonstrate its ability to augment limb arterial blood flow and improve ischemic limbs. To determine the device's efficacy and safety, and possibly confirm earlier positive reports, a systematic study was undertaken, using older, as well as newer, more electronically reliable CSC devices. The present study was designed to determine the following: 1. objectively, by noninvasive vascular tests, changes in limb blood flow, if any, by CSC; 2. clinical effects of CSC, if any, on the ischemic limb; 3. duration of CSC-induced limb improvements, if any; 4. side effects or safety of CSC. The study demonstrated that CSC treatments: 1. caused increased limb blood flow as determined by increased ankle/arm indices and hallux photoplethysmograph waveform amplitudes during treatments; 2. led, in most cases, to improvement in or resolution of the presenting ischemic problem (eg, ulcer, cellulitis, rest pain); 3. induced limb improvements that persist for up to seven years 4. caused no adverse side effects.

MAST Suit Update

In recent years, the use of the MAST suit has become commonplace. While no controlled human studies have shown the device's efficacy, extensive clinical experience suggests that it is practical and useful in combating shock, stabilizing fractures, and promoting hemostasis. Studies indicate that the antishock trousers elevate blood pressure primarily by increasing peripheral vascular resistance. Proper application and removal of the device are crucial. A number of potential complications exist, but are infrequent and rarely should preclude MAST suit use. Further studies are necessary to prove the efficacy of the device and clearly define its role in patient management.