scholarly journals A novel non-invasive, non-conductive method for measuring respiration

2020 ◽  
Vol 9 (1) ◽  
pp. 27-32 ◽  
Author(s):  
Jan Ringkamp ◽  
Philipp Radler ◽  
Philipp Lebhardt ◽  
Jens Langejürgen
Keyword(s):  
High Frequency ◽  
Effective Permittivity ◽  
Artificial Lung ◽  
High Reproducibility ◽  
Promising Candidate ◽  
Dynamic Changes ◽  
Non Invasive ◽  
Respiratory Parameters ◽  
Strong Linear Correlation ◽  
Novel Method

Abstract. We present a novel method for measuring dynamic changes in respiration parameters due to breathing based on the coupling of two ultra-high-frequency (UHF) antennae. For evaluation, we built a dynamic 3-D printed phantom encasing two compartments separated by an elastic diaphragm. By filling this artificial lung with air the effective permittivity in the compartment changes, resulting in a significant variation of the S21 parameter's magnitude and phase. We show that there is a strong linear correlation between the volume of air in the artificial lung and the magnitude (in dB) of the S21 parameter (R2=0.997) as well as the parameter's phase (R2=0.975). Our sensor system shows a high reproducibility (standard deviation of predicted volume =0.67 mL) and a timing similar to a conventional flow sensor (delay =5.33 ms). The presented method is a promising candidate to overcome some of the most important technical burdens of measuring respiratory parameters and might be used as a trigger for patient–ventilator synchronization in infants and neonates.

scholarly journals Respiration parameter determination with non-obstructive methods

2020 ◽  
Vol 18 ◽  
pp. 89-95
Author(s):  
Sven Fisahn ◽  
Christian Siebauer ◽  
Jan Ringkamp ◽  
Kirsten J. Dehning ◽  
Stefan Zimmermann ◽  
...  
Keyword(s):  
Tidal Volume ◽  
High Frequency ◽  
Positive Airway Pressure ◽  
Artificial Ventilation ◽  
Parameter Determination ◽  
Dynamic Changes ◽  
Endotracheal Tubes ◽  
Respiratory Parameters ◽  
Lung Phantom ◽  
Difference Time

Abstract. Measuring respiratory parameters like the breathing frequency or the tidal volume is essential in intensive care to ensure an optimal and lung protecting ventilation. A common practice in artificial ventilation of sensitive patients like infants or neonates is the use of uncuffed endotracheal tubes in combination with continuous positive airway pressure (CPAP). This comes with the disadvantage of an unknown leakage making it difficult to detect spontaneous breathing or to measure the tidal volume reliable. A novel non-obstructive method to determine respiratory parameters as well as dynamic changes of thoracic parameters has recently been presented and uses a pair of coupled UHF (ultra high frequency) antennae. In this paper, a respective setup is investigated numerically using finite difference time domain method and experimentally using an artificial lung phantom. Both approaches show that the investigated method seems capable of allowing a contactless triggering to synchronize natural and artificial breathing. The results are compared to derive a better understanding of influencing factors and opportunities for an optimisation.

Bee Markers: A Novel Method for Non-Invasive Short Term Marking of Bats

2020 ◽  
Vol 21 (2) ◽  
pp. 465 ◽  
Author(s):  
Lucinda Kirkpatrick ◽  
Grzegorz Apoznański ◽  
Luc De Bruyn ◽  
Ralf Gyselings ◽  
Tomasz Kokurewicz
Keyword(s):  
Short Term ◽  
Non Invasive ◽  
Novel Method

scholarly journals Non-invasive high-frequency oscillatory ventilation in preterm infants after extubation: a randomized, controlled trial

2021 ◽  
Vol 49 (2) ◽  
pp. 030006052098491
Author(s):  
Yan Li ◽  
Qiufen Wei ◽  
Dan Zhao ◽  
Yan Mo ◽  
Liping Yao ◽  
...  
Keyword(s):  
Randomized Controlled Trial ◽  
Preterm Infants ◽  
High Frequency ◽  
Controlled Trial ◽  
High Frequency Oscillatory Ventilation ◽  
Positive Pressure ◽  
Non Invasive ◽  
Randomized Controlled ◽  
Oscillatory Ventilation ◽  
High Frequency Oscillatory

Objective To investigate the effectiveness and safety of non-invasive high-frequency oscillatory ventilation (NHFOV) in post-extubation preterm infants. Methods This was a randomized, controlled trial. A total of 149 preterm infants aged between 25 to 34 weeks’ gestational age with a birth weight of <1500 g who required invasive mechanical ventilation on admission were included. After extubation, they were randomized to the NHFOV group (n = 47), nasal intermittent positive pressure ventilation (NIPPV) group (n = 51), or nasal continuous positive airway pressure (NCPAP) group (n = 51). We compared the effectiveness and safety among these three groups. Results A total of 139 preterm infants finally completed the study. The reintubation rate was significantly lower in the NHFOV group than in the other groups. The duration of non-invasive ventilation and the length of hospital stay in the NHFOV and NIPPV groups were significantly shorter than those in the NCPAP group. The incidence of bronchopulmonary dysplasia in the NHFOV and NIPPV groups was significantly lower than that in the NCPAP group. The NHFOV group had significantly less nasal injury than the NCPAP group. Conclusion As post-extubation respiratory support in preterm infants, NHFOV has a lower reintubation rate compared with NCPAP and NIPPV, without increasing the rate of complications.

Increased high-frequency heart rate variability during insulin-induced hypoglycaemia in healthy humans

2004 ◽  
Vol 106 (6) ◽  
pp. 583-588 ◽  
Author(s):  
Hartmut SCHÄCHINGER ◽  
Johannes PORT ◽  
Stuart BRODY ◽  
Lilly LINDER ◽  
Frank H. WILHELM ◽  
...  
Keyword(s):  
Heart Rate ◽  
High Frequency ◽  
Concomitant Increase ◽  
Plasma Adrenaline ◽  
Non Invasive ◽  
Hyperinsulinaemic Clamp ◽  
Healthy Humans ◽  
Plasma Insulin Levels ◽  
Single Blind ◽  
Cardiac Autonomic Activity

Despite causing sympathetic activation, prolonged hypoglycaemia produces little change in HR (heart rate) in healthy young adults. One explanation could be concurrent parasympathetic activation, resulting in unchanged net effects of autonomic influences. In the present study, hypoglycaemic (2.7 mmol/l) and normoglycaemic (4.7 mmol/l) hyperinsulinaemic clamp studies were performed after normoglycaemic baseline clamp periods with 15 healthy volunteers (seven male; mean age, 27 years) on two occasions in a randomized single-blind cross-over design. Non-invasive indices of cardiac autonomic activity and hormones were measured at baseline and 1 h after the beginning of hypoglycaemia or control normoglycaemia. Plasma insulin levels and mean HR were similar during both conditions. During hypoglycaemia, there was a 485% increase in plasma adrenaline (epinephrine). A shortening of the pre-ejection period by 45% suggested strong sympathetic cardiac activation. High-frequency (0.15–0.45 Hz) HRV (HR variability) increased, indicating a concomitant increase in parasympathetic tone. Thus, during hypoglycaemia-induced sympathetic cardiac activation in healthy adults, parasympathetic mechanisms are involved in stabilizing mean HR.

Nutrient and hormone levels in Douglas-fir corrosion cavities, megagametophytes, and embryos during embryony

2005 ◽  
Vol 35 (10) ◽  
pp. 2447-2456 ◽  
Author(s):  
John G Carman ◽  
Gordon Reese ◽  
Rodney J Fuller ◽  
Timnit Ghermay ◽  
Roger Timmis
Keyword(s):  
Pseudotsuga Menziesii ◽  
Dry Mass ◽  
Douglas Fir ◽  
Chemical Analyses ◽  
Dynamic Changes ◽  
Hormone Levels ◽  
Corrosion Cavity ◽  
Novel Method ◽  
Indole 3 Acetic Acid

Gymnospermous embryos are nourished by fluids secreted from the megagametophyte. During early embryony, these fluids occupy the newly formed corrosion cavity. We describe a novel method for extracting corrosion cavity fluid and provide chemical analyses based on extractions from approximately 120 000 Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) megagametophytes. Levels of potassium, phosphorus, calcium, zinc, and iron were higher in corrosion cavity fluid than in whole tissue, but levels of sulphur and manganese were lower. Levels of cyclitols, sucrose equivalents, erythrose, and arabinose were many-fold higher in corrosion cavity fluid than in whole tissues. Ala, Ser, Arg, Glx, and NH3 exceeded 80 mmol/kg dry mass in corrosion cavity fluid. These levels were about 100-fold higher than those found in whole tissues. During early embryony, hormone levels in corrosion cavity fluid were higher than levels observed in whole megagametophytes by 120-fold for indole-3-acetic acid, 53-fold for abscisic acid, and 8- to 10-fold for cytokinins. Nutrient and hormone levels tended to be much higher in the corrosion cavity fluid than would have been predicted based on whole-tissue analyses. Dynamic changes in nutrient and hormone levels occurred over time in the corrosion cavity, and these changes may normalize embryony in situ.

scholarly journals A Neuromorphic Spiking Neural Network Detects Epileptic High Frequency Oscillations in the Scalp EEG

2021 ◽  
Author(s):  
Karla Burelo ◽  
Georgia Ramantani ◽  
Giacomo Indiveri ◽  
Johannes Sarnthein
Keyword(s):  
Low Power ◽  
Seizure Frequency ◽  
High Frequency ◽  
Therapy Monitoring ◽  
Non Invasive ◽  
Scalp Eeg ◽  
High Frequency Oscillations ◽  
Eeg Recordings ◽  
Active Epilepsy ◽  
Wearable Electronic Devices

Abstract Background: Interictal High Frequency Oscillations (HFO) are measurable in scalp EEG. This has aroused interest in investigating their potential as biomarkers of epileptogenesis, seizure propensity, disease severity, and treatment response. The demand for therapy monitoring in epilepsy has kindled interest in compact wearable electronic devices for long- term EEG recording. Spiking neural networks (SNN) have been shown to be optimal architectures for being embedded in compact low-power signal processing hardware. Methods: We analyzed 20 scalp EEG recordings from 11 patients with pediatric focal lesional epilepsy. We designed a custom SNN to detect events of interest (EoI) in the 80-250 Hz ripple band and reject artifacts in the 500-900 Hz band. Results: We identified the optimal SNN parameters to automatically detect EoI and reject artifacts. The occurrence of HFO thus detected was associated with active epilepsy with 80% accuracy. The HFO rate mirrored the decrease in seizure frequency in 8 patients (p = 0.0047). Overall, the HFO rate correlated with seizure frequency (rho = 0.83, p < 0.0001, Spearman’s correlation).Conclusions: The fully automated SNN detected clinically relevant HFO in the scalp EEG. This is a further step towards non-invasive epilepsy monitoring with a low-power wearable device.

scholarly journals The effect of vascular diseases on bioimpedance measurements: mathematical modeling

2018 ◽  
Vol 5 (6) ◽  
Author(s):  
Yomna H. Shash ◽  
Mohamed A. A. Eldosoky ◽  
Mohamed T. Elwakad
Keyword(s):  
Mathematical Models ◽  
Vessel Wall ◽  
Vascular Diseases ◽  
Impedance Analysis ◽  
Wide Field ◽  
Vascular Disorders ◽  
Non Invasive ◽  
Novel Method ◽  
Inner Vessel ◽  
Arteries And Veins

Introduction: The non-invasive nature of bioimpedance technique is the reason for the adoption of this technique in the wide field of bio-research. This technique is useful in the analysis of a variety of diseases and has many advantages. Cardiovascular diseases are the most dangerous diseases leading to death in many regions of the world. Vascular diseases are disorders that affect the arteries and veins. Most often, vascular diseases have greater impacts on the blood flow, either by narrowing or blocking the vessel lumen or by weakening the vessel wall. The most common vascular diseases are atherosclerosis, wall swelling (aneurysm), and occlusion. Atherosclerosis is a disease caused by the deposition of plaques on the inner vessel wall, while a mural aneurysm is formed as a result of wall weakness. The main objective of this study was to investigate the effects of vascular diseases on vessel impedance. Furthermore, this study aimed to develop the measurement of vessel abnormalities as a novel method based on the bioimpedance phenomenon. Methods: Mathematical models were presented to describe the impedance of vessels in different vascular cases. In addition, a 3D model of blood vessels was simulated by COMSOL MULTIPHYSICS.5, and the impedance was measured at each vascular condition. Results: The simulation results clarify that the vascular disorders (stenosis, blockage or aneurysm) have significant impact on the vessel impedance, and thus they can be detected by using the bio-impedance analysis. Moreover, using frequencies in KHz range is preferred in detecting vascular diseases since it has the ability to differentiate between the healthy and diseased blood vessel. Finally, the results can be improved by selecting an appropriate electrodes configuration for analysis. Conclusion: From this work, it can be concluded that bioimpedance analysis (BIA) has the ability to detect vascular diseases. Furthermore, the proposed mathematical models are successful at describing different cases of vascular disorders.

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