CAAos platform: an integrated platform for analysis of cerebral hemodynamics data
Objective. The purpose of this article is to introduce readers to the concept and structure of the
CAAos ( C erebral A utoregulation A ssessment O pen S ource) platform, and provide evidence of its
functionality. Approach. The CAAos platform is a new open-source software research tool, developed
in Python 3 language, that combines existing and novel methods for interactive visual inspection,
batch processing and analysis of multichannel records. The platform is scalable, allowing for the
customization and inclusion of new tools. Main results. Currently, the CAAos platform is composed of
two main modules, preprocessin...
Source: Physiological Measurement - October 28, 2021 Category: Physiology Authors: Jo ão Salinet, Fernando Silva de Moura, Renata Romaneli, Pedro Machado Nery dos Santos, Matheus Zamai, Ronney B Panerai, Andre M Duarte, Edson Bor-Seng-Shu and Angela Salomao Macedo Salinet Source Type: research
Night to night variability of pulse oximetry features in children at home and at the hospital
Objective . Investigation of the night-to-night (NtN) variability of pulse oximetry features in
children with suspicion of Sleep Apnea. Approach . Following ethics approval and informed consent,
75 children referred to British Columbia Children's Hospital for overnight PSG were recorded on
three consecutive nights, including one at the hospital simultaneously with polysomnography and 2
nights at home. During all three nights, a smartphone-based pulse oximeter sensor was used to record
overnight pulse oximetry (SpO2 and photoplethysmogram). Features characterizing SpO2 dynamics and
heart rate were derived. The NtN var...
Source: Physiological Measurement - October 28, 2021 Category: Physiology Authors: Xenia L R Hoppenbrouwer, Aryannah U Rollinson, Dustin Dunsmuir, J Mark Ansermino, Guy Dumont, Wendy Oude Nijeweme-d ’Hollosy, Peter Veltink and Ainara Garde Source Type: research
Estimating confidence intervals for cerebral autoregulation: a parametric bootstrap approach
The objective of this paper is to present a novel parametric bootstrap method,
used to estimate the sampling distribution and hence confidence intervals (CIs) of the mean phase
estimate in the low-frequency band, in order to optimise estimation of measures of CA function and
allow more robust inferences on the status of CA from individual recordings. A set of simulations
was used to veri... (Source: Physiological Measurement)
Source: Physiological Measurement - October 28, 2021 Category: Physiology Authors: Jack E D Bryant, Anthony A Birch, Ronney B Panerai, Dragana Nikolic, Diederik Bulters and David M Simpson Source Type: research
Estimation of aortic pulse wave velocity based on waveform decomposition of central aortic pressure
waveform
In this study, the aortic PWV is estimated using a single radial pressure
waveform and compared with cfPWV. 111 subjects ’ aortic PWVs are estimated from the decomposition of
the derived central aortic pressure waveform based on three types of reconstructed flow waveform:
the peak of triangular flow waveform based on 30% ejection time ( Q 30%tri ), the peak of triangular
flow waveform based on inflection point ( Q tri ), and averaged flow waveform ( Q avg ). The central
aortic pressure waveform is derived from a radial pressure waveform via a validated transfer
function. Main results. The Q (Source: Physiological Measurement)
Source: Physiological Measurement - October 28, 2021 Category: Physiology Authors: Wenyan Liu, Yang Yao, Jinzhong Yang, Daiyuan Song, Yuelan Zhang, Guozhe Sun, Lisheng Xu and Alberto Avolio Source Type: research
Ventilation improvement after pneumonia treatment evaluated with electrical impedance tomography: an
observational study
Objective. Due to radiation exposure, not all patients with pneumonia receive chest x-rays or CT
measurements to confirm treatment effectiveness. The aim of this study was to examine the ability to
use electrical impedance tomography (EIT) to evaluate the treatment effectiveness in such patient
group. Approach . A total of 35 consecutive patients with non-severe pneumonia were included in this
prospective study. The patients received standard treatment according to our internal protocol. EIT
measurements were performed in supine position before the treatment started and on day 6 of the
treatment period. The EIT-based...
Source: Physiological Measurement - October 28, 2021 Category: Physiology Authors: Hong-Ying Jiang, Qing Li, Xin Yu, Chen-Xi Zhang, Yi Li, Guang-Yu Niu, Zhao-Hui Tong, Jia-Ning Xi and Zhanqi Zhao Source Type: research
Comment on ‘pulse rate variability in cardiovascular health: a review on its applications and
relationship with heart rate variability ’
Description unavailable (Source: Physiological Measurement)
Source: Physiological Measurement - October 6, 2021 Category: Physiology Authors: Jacquelin Peck, Michael J Wishon, Harrison Wittels, Hector Davila, S Howard Wittels and Stephen J. Lee Source Type: research
Dynamic lung behavior under high G acceleration monitored with electrical impedance tomography
Objective . During launch and atmospheric re-entry in suborbital space flights, astronauts are
exposed to high G-acceleration. These acceleration levels influence gas exchange inside the lung and
can potentially lead to hypoxaemia. The distribution of air inside the lung can be monitored by
electrical impedance tomography. This imaging technique might reveal how high gravitational forces
affect the dynamic behavior of ventilation and impair gas exchange resulting in hypoxaemia. Approach
. We performed a trial in a long-arm centrifuge with ten participants lying supine while being
exposed to +2, +4 and +6 G x (chest-t...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Tobias Menden, Gema B Alca ín, Alec T Stevenson, Ross D Pollock, Henry Tank, Peter Hodkinson, Caroline Jolley, Thomas G Smith, Steffen Leonhardt and Marian Walter Source Type: research
Physiological vital sign reference ranges for well late preterm newborns calculated during a typical
2 h newborn period between 2 h and 7 days of life
Objectives . To calculate 95% reference ranges for heart rate, respiratory rate, oxygen saturation,
temperature and blood pressure for well late preterm newborns between 34 +0/7 and 36 +6/7 weeks of
gestation during typical neonatal behaviour. Approach. A single-site, prospective cohort study in a
major Australian quaternary hospital between February and September 2019. A total of 120 late
preterm newborns had their heart rate, respiratory rate and oxygen saturation measurements recorded
every 2 s for up to 2 h with unconditional 95% reference ranges determined using a linear mixed
effects model with random intercept...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Michelle Paliwoda, Karen New, Fiona Bogossian and Emma Ballard Source Type: research
Quantification of sweat urea in diabetes using electro-optical technique
OBJECTIVE: To develop a device for quantifying sweats urea concentration. APPROACH: The proposed
optical device uses light source, light sensor with time and intensity controlled operation. Sweat
samples are collected from a group of volunteers belonging to control and diabetes. After
sedimentation and suitable pre-processing, sweat samples are irradiated by primary colour light
sources operated sequentially. Reflected light intensity is used to compute the sweat urea
concentration. At first the test is performed using aqueous solution with known urea concentration.
After ascertaining the correctness of the device, t...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Sudha S, Kalpana R and Soundararajan P Source Type: research
Deep learning based classification of unsegmented phonocardiogram spectrograms leveraging transfer
learning
Objective. Cardiovascular diseases (CVDs) are a main cause of deaths all over the world. This
research focuses on computer-aided analysis of phonocardiogram (PCG) signals based on deep learning
that can enable improved and timely detection of heart abnormalities. The two widely used publicly
available PCG datasets are from the PhysioNet/CinC (2016) and PASCAL (2011) challenges. The datasets
are significantly different in terms of the tools used for data acquisition, clinical protocols,
digital storages and signal qualities, making it challenging to process and analyze. Approach. In
this work, we have used short-time ...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Kaleem Nawaz Khan, Faiq Ahmad Khan, Anam Abid, Tamer Olmez, Zumray Dokur, Amith Khandakar, Muhammad E H Chowdhury and Muhammad Salman Khan Source Type: research
Motion robust ICG measurements using a two-step spectrum denoising method
Objective . Impedance cardiography (ICG) is a noninvasive and continuous method for evaluating
stroke volume and cardiac output. However, the ICG measurement is easily interfered due to
respiration and body movements. Taking into consideration about the spectral correlations between
the simultaneously collected ICG, electrocardiogram (ECG), and acceleration signals, this paper
introduces a two-step spectrum denoising method to remove motion artifacts of ICG measurements in
both resting and exercising scenarios. Approach . First, the major motion artifacts of ECG and ICG
are separately suppressed by the spectral subtr...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Yao Xie, Rencheng Song, Dong Yang, Honglong Yu, Cuimin Sun, Qilian Xie and Ronald X Xu Source Type: research
Executive dysfunction after multiple concussions is not related to cerebrovascular dysfunction
Objective. We investigated the relation between prior concussion history and working memory (WM),
self-reported cognitive symptom burden, and cerebrovascular function in adolescents and young adults
(14 –21 years old). Approach. We recruited 59 participants, 34 clinically diagnosed with a
sports-related concussion and 25 controls. Concussed subjects were studied at baseline (within 28
days of their injury) and eight weeks after, while control subjects only had one assessment. We
assessed WM ( n -back task up to four-back), and neurovascular coupling (cerebrovascular responses
at middle cerebral artery during n -bac...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Erin D Ozturk, Mary Alexis Iaccarino, Jason W Hamner, Stacey E Aaron, Danielle L Hunt, William P Meehan III, David R Howell and Can Ozan Tan Source Type: research
External validation of a novel signature of illness in continuous cardiorespiratory monitoring to
detect early respiratory deterioration of ICU patients
Objective: The goal of predictive analytics monitoring is the early detection of patients at high
risk of subacute potentially catastrophic illnesses. An excellent example of a targeted illness is
respiratory failure leading to urgent unplanned intubation, where early detection might lead to
interventions that improve patient outcomes. Previously, we identified signatures of this illness in
the continuous cardiorespiratory monitoring data of intensive care unit (ICU) patients and devised
algorithms to identify patients at rising risk. Here, we externally validated three logistic
regression models to estimate the risk...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Rachael A Callcut, Yuan Xu, J Randall Moorman, Christina Tsai, Andrea Villaroman, Anamaria J Robles, Douglas E Lake, Xiao Hu and Matthew T Clark Source Type: research
Electrical-tomographic imaging of physiological-induced conductive response in calf muscle
compartments during voltage intensity change of electrical muscle stimulation ( vic -EMS)
Objectives . The electrical-tomographic imaging has been achieved for exploring differential
tendency of physiological-induced conductive response in calf muscle compartments during voltage
intensity change of electrical muscle stimulation ( vic -EMS). Approach . In the experiments, the
differential tendency of conductivity distribution images σ during vic -EMS were clearly imaged as
three responsive muscle compartments, which are called M 1 compartment composed of gastrocnemius
muscle, M 2 compartment composed of tibialis anterior, extensor digitorum longus, and peroneus
longus muscles, and M 3 compartment composed...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Bo Sun, Panji Nursetia Darma, Tomoyuki Shirai, Kosei Narita and Masahiro Takei Source Type: research
Continuous cardiorespiratory monitoring is a dominant source of predictive signal in machine
learning for risk stratification and clinical decision support *
Beaulieu-Jones and coworkers propose a litmus test for the field of predictive analytics —performance
improvements must be demonstrated to be the result of non-clinician-initiated data, otherwise, there
should be caution in assuming that predictive models could improve clinical decision-making
(Beaulieu-Jones et al 2021). They demonstrate substantial prognostic information in unsorted
physician orders made before the first midnight of hospital admission, and we are persuaded that it
is fair to ask —if the physician thought of it first, what exactly is machine learning for in-patient
risk stratification learning a...
Source: Physiological Measurement - September 27, 2021 Category: Physiology Authors: Oliver Monfredi, Jessica Keim-Malpass and J Randall Moorman Source Type: research
