Feasibility of bioelectrical impedance spectroscopy measurement before and after thoracentesis.

Background: Bioelectrical impedance spectroscopy is applied to measure changes in tissue composition. The aim of this study was to evaluate its feasibility in measuring the fluid shift after thoracentesis in patients with pleural effusion.

Methods: 45 participants (21 with pleural effusion and 24 healthy subjects) were included.

A bendable and wearable cardiorespiratory monitoring device fusing two noncontact sensor principles.

A mobile device is presented for monitoring both respiration and pulse. The device is developed as a bendable/flexible inlay that can be placed in a shirt pocket or the inside pocket of a jacket. To achieve optimum monitoring performance, the device combines two sensor principles, which work in a safe noncontact way through several layers of cotton or other textiles.

Ambient and Unobtrusive Cardiorespiratory Monitoring Techniques.

Monitoring vital signs through unobtrusive means is a goal which has attracted a lot of attention in the past decade. This review provides a systematic and comprehensive review over the current state of the field of ambient and unobtrusive cardiorespiratory monitoring. To this end, nine different sensing modalities which have been in the focus of current research activities are covered: capacitive electrocardiography, seismo- and ballistocardiography, reflective photoplethysmography (PPG) and PPG imaging, thermography, methods relying on laser or radar for distance-based measurements, video motion analysis, as well as methods using high-frequency electromagnetic fields.

Improvement of force-sensor-based heart rate estimation using multichannel data fusion.

The aim of this paper is to present and evaluate algorithms for heartbeat interval estimation from multiple spatially distributed force sensors integrated into a bed. Moreover, the benefit of using multichannel systems as opposed to a single sensor is investigated. While it might seem intuitive that multiple channels are superior to a single channel, the main challenge lies in finding suitable methods to actually leverage this potential.

Development of a wearable multi-frequency impedance cardiography device.

Cardiovascular diseases as well as pulmonary oedema can be early diagnosed using vital signs and thoracic bio-impedance. By recording the electrocardiogram (ECG) and the impedance cardiogram (ICG), vital parameters are captured continuously. The aim of this study is the continuous monitoring of ECG and multi-frequency ICG by a mobile system.

Electrical Bioimpedance-Controlled Surgical Instrumentation.

A bioimpedance-controlled concept for bone cement milling during revision total hip replacement is presented. Normally, the surgeon manually removes bone cement using a hammer and chisel. However, this procedure is relatively rough and unintended harm may occur to tissue at any time.

Unobtrusive and comprehensive health screening using an intelligent toilet system.

Home monitoring is a promising technology to deal with the increasing amount of chronically ill patients while ensuring quality of medical care. Most systems available today depend on a high degree of interaction between the user and the device. Especially for people relying on advanced levels of care, this scheme is impracticable.

Phloroglucinols from anti-microbial deposit-resins of Australian stingless bees (Tetragonula carbonaria).

Stingless bees accumulate deposits of plant resins that are mixed with beeswax to produce propolis. Previous studies have reported anti-microbial constituents of stingless bee (Tetragonula carbonaria) propolis from East Australia, but several components remained to be characterized. In the search of natural products yet unreported for Australian propolis, four bee deposit-resins of T.

Diversity matters: how bees benefit from different resin sources.

Biodiverse environments provide a variety of resources that can be exploited by consumers. While many studies revealed a positive correlation between biodiversity and consumer biomass and richness, only few studies have investigated how resource diversity affects single consumers. To better understand whether a single consumer species benefits from diverse resources, we tested how the protective function of a defensive plant resource (i.

Monte-Carlo Simulation and Automated Test Bench for Developing a Multichannel NIR-Based Vital-Signs Monitor.

Unobtrusive, long-term monitoring of cardiac (and respiratory) rhythms using only non-invasive vibration sensors mounted in beds promises to unlock new applications in home and low acuity monitoring. This paper presents a novel concept for such a system based on an array of near infrared (NIR) sensors placed underneath a regular bed mattress. We focus on modeling and analyzing the underlying technical measurement principle with the help of a 2D model of a polyurethane foam mattress and Monte-Carlo simulations of the opto-mechanical interaction responsible for signal genesis.

Monitoring of lobectomy in cystic fibrosis with electrical impedance tomography - a new diagnostic tool.

Electrical impedance tomography (EIT) is a radiation-free technique generating cross-sectional images of the lung. EIT visualizes global and regional ventilation by illustrating the distribution of electrical bioimpedance. With an electrode belt around the patient's thorax, rotating injection-couples of a harmless alternating current allow voltage measurement of the remaining electrodes.

A Thorax Simulator for Complex Dynamic Bioimpedance Measurements With Textile Electrodes.

Bioimpedance measurements on the human thorax are suitable for assessment of body composition or hemodynamic parameters, such as stroke volume; they are non-invasive, easy in application and inexpensive. When targeting personal healthcare scenarios, the technology can be integrated into textiles to increase ease, comfort and coverage of measurements. Bioimpedance is generally measured using two electrodes injecting low alternating currents (0.

Control of an electromechanical hydrocephalus shunt--a new approach.

Hydrocephalus is characterized by an excessive accumulation of cerebrospinal fluid (CSF). Therapeutically, an artificial pressure relief valve (so-called shunt) is implanted which opens in case of increased intracranial pressure (ICP) and drains CSF into another body compartment. Today, available shunts are of a mechanical nature and drainage depends on the pressure drop across the shunt.

Microbial communities of three sympatric Australian stingless bee species.

Bacterial symbionts of insects have received increasing attention due to their prominent role in nutrient acquisition and defense. In social bees, symbiotic bacteria can maintain colony homeostasis and fitness, and the loss or alteration of the bacterial community may be associated with the ongoing bee decline observed worldwide. However, analyses of microbiota associated with bees have been largely confined to the social honeybees (Apis mellifera) and bumblebees (Bombus spec.

Bladder volume estimation from electrical impedance tomography.

Non-invasive estimation of bladder volume is required to progress from scheduled voiding to a demand-driven emptying scheme for patients with impaired bladder volume sensation. Electrical impedance tomography (EIT) is a promising candidate for the non-invasive monitoring of bladder volume. This article focuses on four estimation algorithms used to map recorded EIT data to a volume estimate.

Robustness, specificity, and reliability of an in-ear pulse oximetric sensor in surgical patients.

For many years, pulse oximetry has been widely used in the clinical environment for a reliable monitoring of oxygen saturation ( SpO2) and heart rate. But since common sensors are mainly placed to peripheral body parts as finger or earlobe, it is still highly susceptible to reduced peripheral perfusion, e.g.

Automatic protective ventilation using the ARDSNet protocol with the additional monitoring of electrical impedance tomography.

Introduction: Automatic ventilation for patients with respiratory failure aims at reducing mortality and can minimize the workload of clinical staff, offer standardized continuous care, and ultimately save the overall cost of therapy. We therefore developed a prototype for closed-loop ventilation using acute respiratory distress syndrome network (ARDSNet) protocol, called autoARDSNet.

Methods: A protocol-driven ventilation using goal-oriented structural programming was implemented and used for 4 hours in seven pigs with lavage-induced acute respiratory distress syndrome (ARDS).

Influence of physiological sources on the impedance cardiogram analyzed using 4D FEM simulations.

Impedance cardiography is a simple and inexpensive method to acquire data on hemodynamic parameters. This study analyzes the influence of four dynamic physiological sources (aortic expansion, heart contraction, lung perfusion and erythrocyte orientation) on the impedance signal using a model of the human thorax with a high temporal resolution (125 Hz) based on human MRI data. Simulations of electromagnetic fields were conducted using the finite element method.

An adaptive Kalman filter approach for cardiorespiratory signal extraction and fusion of non-contacting sensors.

Background: Extracting cardiorespiratory signals from non-invasive and non-contacting sensor arrangements, i.e. magnetic induction sensors, is a challenging task.

Bioelectrical impedance spectroscopy as a fluid management system in heart failure.

Episodes of hospitalization for heart failure patients are frequent and are often accompanied by fluid accumulations. The change of the body impedance, measured by bioimpendace spectroscopy, is an indicator of the water content. The hypothesis was that it is possible to detect edema from the impedance data.

The IMPACT shirt: textile integrated and portable impedance cardiography.

Measurement of hemodynamic parameters such as stroke volume (SV) via impedance cardiography (ICG) is an easy, non-invasive and inexpensive way to assess the health status of the heart. We present a possibility to use this technology for monitoring risk patients at home. The IMPACT Shirt (IMPedAnce Cardiography Textile) has been developed with integrated textile electrodes and textile wiring, as well as with portable miniaturized hardware.

Usefulness of bioimpedance spectroscopy for detection of hypotensive episode during dialysis.

Using statistical methods, this study investigates whether bioimpedance spectroscopy (BIS) and plasma electrolytes can be used to identify risk of intradialytic hypotension (IDH) based on information obtained during the first half of the dialysis treatment only. Data obtained from 40 patients included information on blood pressure, parameters defined from BIS, plasma electrolytes, and relevant clinical data. Patients were divided into three groups based on their intradialytic decrease in systolic blood pressure (SysBP) and associated symptoms and interventions: (1) Stable SysBP, (2) Asymptomatic unstable SysBP, and (3) symptomatic unstable SysBP.

Recent advances in and limitations of cardiac output monitoring by means of electrical impedance tomography.

Background: Currently, the monitoring of cardiac output (CO) and stroke volume (SV) is mainly performed using invasive techniques. Therefore, performing CO monitoring noninvasively by means of electrical impedance tomography (EIT) would be advantageous for intensive care. Our hypothesis was that, by means of EIT, it is possible to assess heart rate (HR) and to quantify changes in SV due to changes in ventilator settings.

Contact-free monitoring of circulation and perfusion dynamics based on the analysis of thermal imagery.

Acute circulatory disorders are commonly associated with systemic inflammatory response (SIRS) and sepsis. During sepsis, microcirculatory perfusion is compromised leading to tissue hypoperfusion and potentially to multiple organ dysfunction. In the present study, acute lung injury (ALI), one of the major causes leading to SIRS and sepsis, was experimentally induced in six female pigs.

Robust sensor fusion of unobtrusively measured heart rate.

Contactless vital sign measurement technologies often have the drawback of severe motion artifacts and periods in which no signal is available. However, using several identical or physically different sensors, redundancy can be used to decrease the error in noncontact heart rate estimation, while increasing the time period during which reliable data are available. In this paper, we show for the first time two major results in case of contactless heart rate measurements deduced from a capacitive ECG and optical pulse signals.