Reduction of motion artifacts using a two-frequency impedance plethysmograph and adaptive filtering.

IEEE Trans Biomed Eng

Departament d'Enginyeria Electrònica, Universitat Politècnica de Catalunya, Barcelona, Spain.

Published: October 1995

We measured transthoracic impedance in nine presumed healthy adult subjects with a two-frequency plethysmograph at 57 kHz and 185 kHz. The measurement protocol included periods of normal breathing without motion and periods of motion without breathing. We analyzed the cross-correlation and the ratio between the signals at both frequencies for all the different maneuvers. The correlation coefficient was between 0.97 and 1 for breathing, the minimal cross-correlation (0.81) was for simulated obstructive apnea. We found that the amplitude ratio between the two-frequency signals was different for normal breathing and for motion. Based on these results, we designed and tested an adaptive filter to increase the signal-to-artifact ratio (SAR). The increase in SAR (mean +/- standard deviation) compared with the signal at 57 kHz was: 183% +/- 117% for arm movement, 133% +/- 93% for leg movement, and 34% +/- 62% for simulated obstructive apnea.

Download full-text PDF

Source
http://dx.doi.org/10.1109/10.464380DOI Listing

Publication Analysis

Top Keywords

normal breathing
8
breathing motion
8
simulated obstructive
8
obstructive apnea
8
reduction motion
4
motion artifacts
4
artifacts two-frequency
4
two-frequency impedance
4
impedance plethysmograph
4
plethysmograph adaptive
4

Similar Publications

Introduction And Objectives: The fractional exhaled fraction of nitric oxide (FeNO) is used in clinical practice for asthma diagnosis, phenotyping, and therapeutic management. Therefore, accurate thresholds are crucial. The normal FeNO values over lifespan in a respiratory healthy population and the factors related to them remain unclear.

View Article and Find Full Text PDF

Anemia is a critical medical condition in public health concern in tropical and subtropical areas, and understanding its hematological changes is crucial for improving diagnosis, treatment, and prognosis.It manifests through symptoms like weakness, fatigue, pale skin, and shortness of breath due to insufficient hemoglobin or red blood cells to carry adequate oxygen, with severe cases leading to complications such as chest pain. Common causes include blood loss, chronic diseases, and iron and vitamin deficiencies.

View Article and Find Full Text PDF

Objective: Our study aimed to determine the clinical profile and pulmonary function of pediatric patients with Duchenne Muscular Dystrophy (DMD). We also characterized the stages of progression of the disease and determined their potential association with spirometry variables.

Methods: In this cross-sectional study, we used data obtained from a review of medical records of all pediatric patients (0-18 years old) with DMD seen in a multidisciplinary neuromuscular clinic of a tertiary government hospital from August 2018 until March 2020.

View Article and Find Full Text PDF

Achieving high flexibility, breathability, and sensitivity in inorganic semiconductor gas sensors remains a substantial challenge, especially for wearable applications in high-humidity environments. This study develops a hyper-flexible, thermally stable, and highly breathable full-inorganic, self-supporting InGaO-AlO/AlO nanofiber membrane sensor, fabricated using a dual-spinneret electrospinning method with an interlocking design. This innovative sensor has a bilayer structure with an amorphous AlO nanofiber substrate layer supporting an active layer of high-aspect-ratio interwoven InGaO and AlO nanofibers, providing outstanding flexibility, elevated breathability, and strong thermal stability.

View Article and Find Full Text PDF

Prior heatwave exposure improves hypoxia tolerance in a typical freshwater fish species.

Comp Biochem Physiol A Mol Integr Physiol

January 2025

Beijing Normal University, Beijing 100875, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Science, Beijing 100012, China.

The prevalence of heatwave and hypoxia events and their devastating impacts on aquatic ecosystems and fishery resources reinforces the priority of research to address the resilience and adaption mechanisms to these two stressors in important fish species. However, our understanding of the development of cross-tolerance of these two stressors in fish still limited. Here, we investigated the impacts of prior heatwave exposure on hypoxia tolerance and the underlying mechanisms in silver carp (Hypophthalmichthys molitrix), a species of considerable ecological and commercial importance.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!