Dual applicator thermal ablation at 2.45 GHz: a numerical comparison and experiments on synchronous versus asynchronous and switched-mode feeding

This paper compares the results obtained with numerical simulations and ex vivo experiments involving a dual applicator microwave thermal ablation system operating at a 2.45 GHz frequency, both in synchronous and asynchronous modes. Our purpose was to demonstrate that at this frequency an asynchronous or switched-mode system performs essentially as well as the synchronous one, in spite of the prevailing belief that coherence would assure better thermal (TH) synergy. Numerical analysis: The calculations of temperature fields were based on the Pennes bioheat equation, taking into account the effects of blood perfusion by means of a full-wave 3D simulator that allows numerical electromagnetic (EM) and TH analyses.Experiments were done using a 100 W microwave (MW) power generator and a fast switched-mode sequential 'active' power splitter. By adding a further passive power splitter we arranged a test bed for an accurate experimental comparison of synchronous versus switched-mode TH ablations.The experimental ablation zones produced by a dual applicator array on ex vivo swine tissue corresponded well with the simulated ones, confirming that the simplifications assumed in the full-wave analysis were compatible with the aim of our work.Numerical simulations and experiments show that at a 2.45 GHz industrial, scientific and medical (ISM) frequency, synchronous, asynchronous and switched-mode multi-probe systems are substantially equivalent in terms of ablative performance. Moreover, the switched-mode solution offers simpler operation along with lesser sensitivity to the placement of applicators in the tissue

Development of a Novel Switched-Mode 2.45 GHz Microwave Multiapplicator Ablation System

The development of a novel switched-mode 2.45 GHz microwave (MW) multiapplicator system intended for laparoscopic and open surgical thermoablative treatments is presented. The system differs from the other synchronous and asynchronous commercially available equipments because it employs a fast sequential switching (FSS) technique for feeding an array of up to four high efficiency MW applicators. FSS technology, if properly engineered, allows improving system compactness, modularity, overall efficiency, and operational flexibility. Full-wave electromagnetic (EM) and thermal (TH) simulations have been made to confirm the expected performances of the FSS technology. Here we provide an overview of technical details and earlyex-vivoexperiments carried out with a full functionalβ-prototype of the system

Dual Frequency Active RFID Solution for Tracking Patients in a Children's Hospital. Design Method, Test Procedure, Risk Analysis and Techical Solution

This work addresses the problem of reliable identification and tracking of children in an intensive care unit in a children's hospital. Tracking and identification of patients are critical for the clinical risk management process, particularly for a children's hospital intensive care unit where patients' identities can easily be confused. This work offers a multilayer approach to the design of the process of identification and tracking; it gives an active radio-frequency identification (RFID) solution that best fits all the given constraints. The paper is divided in the following sections: design (where a multilayer method is provided, including project aims, functional requirements, and technical constraints); risk analysis [a failure modes and effects analysis (FMEA) method is used to assess the risks of each stage of the process of patient management]; technical solution with a specific test phase and a review of the risk analysis results. As a result of the proposed approach, we got a strong coherence between the initial aims and the technical solution, improving patient safety and reducing the clinical risk in the process of tracking and identifying patients

The role of bioengineer in hospital upkeep and development

In Italy, hospitals of different dimensions have been equipped, in the last years, with a clinical engineering structure that is leaded by a bioengineer whose main role is management of bioinstrumentation in terms of planning for purchases and maintenance. Nevertheless, if we think that hospital structures, particularly those with considerable dimensions, are subject to a nearly continuous upkeep process, we can locate a new crucial role for bioengineers: being the main referents of upkeep process together with hospital’s CEO. The process of upkeep and development of a hospital is always a complex multi-project that involves many steps starting from a deep planning effort. In this process, we maintain, the bioengineer should be involved starting from scratch

Risk Management Process in a Microwave Thermal Ablation System for CE Marking

Microwave thermal ablation (MWA) is a promising technique capable of achieving larger ablation zones quicker than other energy forms. The aim of this work is the risk management of a brand new microwave thermal ablation system, for the purpose of CE marking. The risk analysis will be driven by a multidimensional Failure Mode, Criticality and Effect analysis, which will take into account the effects on the patient, the operator and the hospital facility. All the principal mitigation interventions found will be described

Effects of Combined Use of a Patient-Tracking System and a Smart Drug-Dispenser on the Overall Risk of the Diagnostic-Therapeutic Process

Clinical risk and the incidence of adverse event are relevant problems, that have been subject of many studies during last years. The objective of this study is to assess the potential clinical risk reduction obtained with the combined implementation in the diagnostic-therapeutic process work- flows of a patient-tracking system and a smart drug-dispenser, both based on RFId technology. The study will be driven by a multidimensional FMECA, considering in the risk analysis all the subjects involved in the diagnostic-therapeutic process, not only the dimension of patient safety indeed, but also medical staff dimension and structure (hospital facility) dimension. Mitigation interventions are found and they often result in a further development and enhancement of the functionality of the two studied RFId systems

Dual applicator thermal ablation at 2.45 GHz: a numerical comparison and experiments on synchronous versus asynchronous and switched-mode feeding

This paper compares the results obtained with numerical simulations and ex vivo experiments involving a dual applicator microwave thermal ablation system operating at a 2.45 GHz frequency, both in synchronous and asynchronous modes. Our purpose was to demonstrate that at this frequency an asynchronous or switched-mode system performs essentially as well as the synchronous one, in spite of the prevailing belief that coherence would assure better thermal (TH) synergy. Numerical analysis: The calculations of temperature fields were based on the Pennes bioheat equation, taking into account the effects of blood perfusion by means of a full-wave 3D simulator that allows numerical electromagnetic (EM) and TH analyses.Experiments were done using a 100 W microwave (MW) power generator and a fast switched-mode sequential 'active' power splitter. By adding a further passive power splitter we arranged a test bed for an accurate experimental comparison of synchronous versus switched-mode TH ablations.The experimental ablation zones produced by a dual applicator array on ex vivo swine tissue corresponded well with the simulated ones, confirming that the simplifications assumed in the full-wave analysis were compatible with the aim of our work.Numerical simulations and experiments show that at a 2.45 GHz industrial, scientific and medical (ISM) frequency, synchronous, asynchronous and switched-mode multi-probe systems are substantially equivalent in terms of ablative performance. Moreover, the switched-mode solution offers simpler operation along with lesser sensitivity to the placement of applicators in the tissue

A decision support system for technological planning and management of field hospitals

A well-planned medical response should consider the use of field hospitals 'FHs' specialised for the disasters and planned to guarantee high technical and medical standards. The purpose of this work is to support in locating technical requirements for FHs planning through an analysis of the most important and useful variables for the installation. A review of disaster medicine literature and technical norms has been carried out in order to offer support in individualising functional and technical requirements for FH planning through an analysis of the most important and useful variables for the installation. Three FH types were designed to be used in emergency and disaster medicine according to the kind of event, to the disaster area and to the local health care system capacity. Organisational, technical and technological requirements for each FH area were provided in order to improve hygiene and quality criteria for a safe and efficient system

RFId-based tracking and safety system

In our country and in the international context, there is a continuous interest in the issue of safety and quality of health care. In scientific literature you can find out that the problem of incorrect identification of patients is often due to errors and omissions in the processes of diagnosis and treatment, such as those found in the administration of drugs or in providing treatment. In healthcare risk of error in identification of the patient can be amplified by critical conditions as the treatment of emergency cases, the involvement of more stakeholders in the management of the case and obviously the specific clinical condition of the patient, such as loss of consciousness or confusion. The department identified in the analysis and study of the pilot project was a Department of Intensive Care. The choice of this department comes from the need to increase the security level of the process of identification of patients and to avoid possible trade. The overall goal of this project is to provide a system of aid for the reduction of cases of incorrect identification of the patient and for monitoring the position of the patient within the hospital. Finally we tested benefits and we provided for the residual error of the new process of identification and traceability after the introduction of RFID systems