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The Journal of Thoracic and... Mar 2020
Topics: Heart Rate; Heart-Assist Devices; Hemorrhage; Humans; von Willebrand Factor
PubMed: 31126660
DOI: 10.1016/j.jtcvs.2019.04.023 -
Progress in Neurobiology Oct 2023The relevance of interactions between autonomic and central nervous systems remains unclear for human brain function and health, particularly when both systems are...
The relevance of interactions between autonomic and central nervous systems remains unclear for human brain function and health, particularly when both systems are challenged under sleep deprivation (SD). We measured brain activity (with fMRI), pulse and respiratory signals, and baseline brain amyloid beta burden (with PET) in healthy participants. We found that SD relative to rested wakefulness (RW) resulted in a significant increase in synchronized low frequency (LF, < 0.1 Hz) activity in an autonomically-related network (AN), including dorsal attention, visual, and sensorimotor regions, which we previously found to have consistent temporal coupling with LF pulse signal changes (regulated by sympathetic tone). SD resulted in a significant phase coherence between the LF component of the pulse signal and a medial network with peak effects in the midbrain reticular formation, and between LF component of the respiratory variations (regulated by respiratory motor output) and a cerebellar network. The LF power of AN during SD was significantly and independently correlated with pulse-medial network and respiratory-cerebellar network phase coherences (total adjusted R = 0.78). Higher LF power of AN during SD (but not RW) was associated with lower amyloid beta burden (Cohen's d = 0.8). In sum, SD triggered an autonomic mode of synchronized brain activity that was associated with distinct autonomic-central interactions. Findings highlight the direct relevance of global cortical synchronization to brain clearance mechanisms.
Topics: Humans; Amyloid beta-Peptides; Autonomic Nervous System; Brain; Heart Rate; Nervous System Physiological Phenomena
PubMed: 37516341
DOI: 10.1016/j.pneurobio.2023.102510 -
Sleep Mar 2022This study was designed to test the utility of cardiovascular responses as markers of potentially different environmental noise disruption effects of wind farm compared...
STUDY OBJECTIVES
This study was designed to test the utility of cardiovascular responses as markers of potentially different environmental noise disruption effects of wind farm compared to traffic noise exposure during sleep.
METHODS
Twenty participants underwent polysomnography. In random order, and at six sound pressure levels from 33 dBA to 48 dBA in 3 dB increments, three types of wind farm and two types of road traffic noise recordings of 20-s duration were played during established N2 or deeper sleep, each separated by 20 s without noise. Each noise sequence also included a no-noise control. Electrocardiogram and finger pulse oximeter recorded pulse wave amplitude changes from the pre-noise onset baseline following each noise exposure and were assessed algorithmically to quantify the magnitude of heart rate and finger vasoconstriction responses to noise exposure.
RESULTS
Higher sound pressure levels were more likely to induce drops in pulse wave amplitude. Sound pressure levels as low as 39 dBA evoked a pulse wave amplitude response (Odds ratio [95% confidence interval]; 1.52 [1.15, 2.02]). Wind farm noise with amplitude modulation was less likely to evoke a pulse wave amplitude response than the other noise types, but warrants cautious interpretation given low numbers of replications within each noise type.
CONCLUSIONS
These preliminary data support that drops in pulse wave amplitude are a particularly sensitive marker of noise-induced cardiovascular responses during. Larger trials are clearly warranted to further assess relationships between recurrent cardiovascular activation responses to environmental noise and potential long-term health effects.
Topics: Electrocardiography; Heart Rate; Humans; Noise; Polysomnography; Sleep
PubMed: 34965303
DOI: 10.1093/sleep/zsab302 -
Journal of Clinical Monitoring and... Aug 2019We evaluated the accuracy and precision of a novel non-invasive monitoring device in comparison with conventional monitoring methods used in intensive care units (ICU)....
We evaluated the accuracy and precision of a novel non-invasive monitoring device in comparison with conventional monitoring methods used in intensive care units (ICU). The study device was developed to measure blood pressure, pulse rate, respiratory rate, and oxygen saturation, continuously with a single sensor using the photoplethysmographic technique. Patients who were monitored with arterial pressure lines in the ICU were enrolled. Systolic and diastolic blood pressure, pulse rate, respiratory rate, and arterial oxygen saturation were measured continuously for 30 min at 5-min intervals using the conventional methods and the study device. The primary outcome variable was blood pressure. Blood pressure measured by the study device highly correlated with the arterial pressure line values (correlation coefficients > 0.95). Percent errors for systolic, diastolic and mean blood pressures were 2.4% and 6.7% and 6.5%, respectively. Percent errors for pulse rate, respiratory rate and oxygen saturation were 3.4%, 5.6% and 1.4%, respectively. The non-invasive, continuous, multi-parameter monitoring device presented high level of agreement with the invasive arterial blood pressure monitoring, along with sufficient accuracy and precision in the measurements of pulse rate, respiratory rate, and oxygen saturation.
Topics: Aged; Aged, 80 and over; Arterial Pressure; Blood Pressure; Blood Pressure Determination; Calibration; Critical Care; Female; Heart Rate; Humans; Intensive Care Units; Male; Middle Aged; Monitoring, Physiologic; Oximetry; Photoplethysmography; Prospective Studies; Reproducibility of Results; Respiratory Rate
PubMed: 30284687
DOI: 10.1007/s10877-018-0205-5 -
IEEE Journal of Biomedical and Health... May 2021The main aim of this work is to identify alterations in the morphology of the pulse photoplethysmogram (PPG) signal, due to the exposure of the subjects to a hyperbaric...
The main aim of this work is to identify alterations in the morphology of the pulse photoplethysmogram (PPG) signal, due to the exposure of the subjects to a hyperbaric environment. Additionally, their Pulse Rate Variability (PRV) is analysed to characterise the response of their Autonomic Nervous System (ANS). To do that, 28 volunteers are introduced into a hyperbaric chamber and five sequential stages with different atmospheric pressures from 1 atm to 5 atm are performed. In this work, nineteen morphological parameters of the PPG signal are analysed: the pulse amplitude; eight parameters related to pulse width; eight parameters related to pulse area; and the two two pulse slopes. Also, classical time and frequency parameters of PRV are computed. Notable widening of the pulses width is observed in the stages analysed. The PPG area increases with pressure, with no significant changes when the initial pressure is recovered. These changes in PPG waveform may be caused by an increase in the systemic vascular resistance as a consequence of of vasoconstriction in the extremities, suggesting a sympathetic activation. However, the PRV results show an augmented parasympathetic activity and a reduction in the parameters that characterise the sympathetic response. So, only a sympathetic activation is detected in the peripheral region, as reflected by PPG morphology. The information regarding the ANS and the cardiovascular response that can be extracted from the PPG signal, as well as its compatibility with wet conditions make this signal the most suitable for studying the physiological response in hyperbaric environments.
Topics: Autonomic Nervous System; Extremities; Heart Rate; Humans; Photoplethysmography; Pulse; Signal Processing, Computer-Assisted; Vital Signs
PubMed: 32870804
DOI: 10.1109/JBHI.2020.3020743 -
World Journal of Urology Jan 2023To identify the relationship between fluoroscopy pulse rate and absorbed radiation dose. We compared absorbed radiation dose with common proxy measurements such as...
PURPOSE
To identify the relationship between fluoroscopy pulse rate and absorbed radiation dose. We compared absorbed radiation dose with common proxy measurements such as fluoroscopy time and C-arm reported dose.
METHODS
Using a simulated patient model, 60 s fluoroscopy exposures were performed using pulse rates of 30, 8, 4, 2, and 1 pulse(s) per second. Each experiment was performed with both standard and low-dose settings using a GE OEC 9800 plus C-arm. Landauer nanoDot™ OSL dosimeters were used to measure the absorbed radiation dose.
RESULTS
Fluoroscopy pulse rate and absorbed radiation dose demonstrated a linear correlation for both standard (R = 0.995, p < 0.001) and low-dose (R = 0.998, p < 0.001) settings. For any given pulse rate, using the low-dose setting reduced absorbed radiation dose by 58 ± 2.8%. Fluoroscopy time demonstrated a linear relationship with absorbed radiation dose for both standard (R = 0.996, p < 0.001) and low-dose (R = 0.991, p < 0.001) settings, but did not change with use of the low-dose setting. C-arm reported radiation dose correlated linearly with absorbed dose (R = 0.999) but consistently under-estimated measured values by an average of 49 ± 3.5%. Using a combination of 1 pulse-per-second and low-dose fluoroscopy, absorbed dose was reduced by 97.7 ± 0.1% compared to standard dose and 30 pulse-per-second settings.
CONCLUSION
Absorbed radiation dose decreases linearly with fluoroscopy pulse rate during equivalent exposure times. Adjusting fluoroscopy pulse rate and utilizing low-dose settings significantly reduces overall absorbed radiation exposure by up to 98%.
Topics: Humans; Radiation Dosage; Heart Rate; Radiation Exposure; Fluoroscopy; Patients
PubMed: 36525105
DOI: 10.1007/s00345-022-04238-2 -
Sensors (Basel, Switzerland) Dec 2022Pulse wave and pulse rate are important indicators of cardiovascular health. Technologies that can check the pulse by contacting the skin with optical sensors built into...
Pulse wave and pulse rate are important indicators of cardiovascular health. Technologies that can check the pulse by contacting the skin with optical sensors built into smart devices have been developed. However, this may cause inconvenience, such as foreign body sensation. Accordingly, studies have been conducted on non-contact pulse rate measurements using facial videos focused on the indoors. Moreover, since the majority of studies are conducted indoors, the error in the pulse rate measurement in outdoor environments, such as an outdoor bench, car and drone, is high. In this paper, to deal with this issue, we focus on developing a robust pulse measurement method based on facial videos taken in diverse environments. The proposed method stably detects faces by removing high-frequency components of face coordinate signals derived from fine body tremors and illumination conditions. It optimizes for extracting skin color changes by reducing illumination-caused noise using the Cg color difference component. The robust pulse wave is extracted from the Cg signal using FFT-iFFT with zero-padding. It can eliminate signal-filtering distortion effectively. We demonstrate that the proposed method relieves pulse rate measurement problems, producing 3.36, 5.81, and 6.09 bpm RMSE for an outdoor bench, driving car, and flying drone, respectively.
Topics: Heart Rate; Video Recording; Face; Videotape Recording; Heart; Algorithms; Signal Processing, Computer-Assisted
PubMed: 36502086
DOI: 10.3390/s22239373 -
Journal of Nepal Health Research Council Nov 2022The use of face masks has been associated with physiological changes in body. This study aims to know the changes in pulse rate and blood pressure components after...
BACKGROUND
The use of face masks has been associated with physiological changes in body. This study aims to know the changes in pulse rate and blood pressure components after wearing face masks during stairs climbing.
METHODS
An experimental study was conducted among 60 apparently healthy young adults between 18-35 years of age. The pulse rate and blood pressure of the participants were recorded during rest at ground floor and after climbing the stairs till 5th floor at brisk and regular pace without wearing the face masks. The uniform KN95 masks were distributed and proper coverage of nose, mouth and chin were ensured. After 5 minutes interval, the pulse rate and blood pressure were recorded again at rest in ground floor and after climbing stairs with use of KN95 masks.
RESULTS
At rest, the difference in mean pulse rate was statistically significant after wearing masks in participants between 21-25 years of age (86.46±14.59 bpm, p=0.014). After climbing the stairs, the mean pulse rate (131.16±18.48 bpm), mean systolic blood pressure (137.67±16.13 mmHg) and mean rate pressure product (182.87±41.70) were higher in participants (age group: 26-30 years) wearing masks and the difference was statistically significant (p=0.001; 0.013; 0.001respectively). During stairs climbing, the change in mean systolic blood pressure (32.66±16.73 mmHg), mean pulse pressure (43.77±24.64 mmHg) and mean rate pressure product (96.58±37.23) were higher in participants (age group: 26-30 years) and the difference was statistically significant (p=0.036; 0.047 and 0.009 respectively).
CONCLUSIONS
The changes in systolic blood pressure, pulse pressure and rate pressure product are found to increase after wearing face masks during stairs climbing. It can be suggestive of increase workload to the heart by wearing face masks in addition to climbing the stairs.
Topics: Young Adult; Humans; Adult; Blood Pressure; Heart Rate; Masks; Nepal
PubMed: 36550734
DOI: 10.33314/jnhrc.v20i02.3848 -
Zoo Biology Sep 2021Magnesium is involved in a variety of physiological processes in marine animals and is known to be deleterious in both excess and deficiency. The effects of magnesium...
Magnesium is involved in a variety of physiological processes in marine animals and is known to be deleterious in both excess and deficiency. The effects of magnesium concentration ranging from 700 mg/L (low), 1344 mg/L (control), and 2000 mg/L (high) on size and pulse rate in upside-down jellyfish (Cassiopea andromeda) medusae were examined in two separate 28-day trials. Exposure to low magnesium resulted in significantly (p < .05) higher pulse rates and decreased bell diameter and also produced oral arm degradation. Exposure to high magnesium resulted in significantly (p < .05) lower pulse rates and decreased bell diameter as well as oral arm cupping. In both low and high magnesium, almost all specimens changed color from pale blue on Day 1, to brown by Day 28, suggesting a loss of zooxanthellae. The decrease in bell diameter and color change was more pronounced and occurred more rapidly in low magnesium. The results of both trials demonstrate the deleterious effects of high and low magnesium on C. andromeda and emphasize the importance of monitoring magnesium concentration to maintain healthy display animals in public aquaria.
Topics: Animals; Animals, Zoo; Heart Rate; Magnesium; Scyphozoa
PubMed: 34124804
DOI: 10.1002/zoo.21631 -
Clinical Neurophysiology : Official... Jan 2023
Topics: Humans; Electric Stimulation; Heart Rate
PubMed: 36402724
DOI: 10.1016/j.clinph.2022.10.013