Non-contact respiration monitoring using impulse radio ultrawideband radar in neonates

Vital sign monitoring in neonates requires adhesive electrodes, which often damage fragile newborn skin. Because impulse radio ultrawideband (IR-UWB) radar has been reported to recognize chest movement without contact in adult humans, IR-UWB may be used to measure respiratory rates (RRs) in a non-contact fashion. We investigated the feasibility of radar sensors for respiration monitoring in neonates without any respiratory support to compare the accuracy and reliability of radar measurements with those of conventional impedance pneumography measurements. In the neonatal intensive care unit, RRs were measured using radar (RR Rd ) and impedance pneumography (RR IP ) simultaneously. The neonatal voluntary movements were measured using the radar sensor and categorized into three levels (low [M 0 ], intermediate [M 1 ] and high [M 2 ]). RR Rd highly agreed with RR IP ( r = 0.90; intraclass correlation coefficient [ICC] = 0.846 [0.835–0.856]). For the M 0 movement, there was good agreement between RR Rd and RR IP (ICC = 0.893; mean bias −0.15 [limits of agreement (LOA) −9.6 to 10.0]). However, the agreement was slightly lower for the M 1 (ICC = 0.833; mean bias = 0.95 [LOA −11.4 to 13.3]) and M 2 (ICC = 0.749; mean bias = 3.04 [LOA –9.30 to 15.4]) movements than for the M 0 movement. In conclusion, IR-UWB radar can provide accurate and reliable estimates of RR in neonates in a non-contact fashion. The performance of radar measurements could be affected by neonate movement.

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Feasibility of non-contact cardiorespiratory monitoring using impulse-radio ultra-wideband radar in the neonatal intensive care unit

PLoS ONE ◽

10.1371/journal.pone.0243939 ◽

2020 ◽

Vol 15 (12) ◽

pp. e0243939

Author(s):

Won Hyuk Lee ◽

Yonggu Lee ◽

Jae Yoon Na ◽

Seung Hyun Kim ◽

Hyun Ju Lee ◽

...

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Neonatal Intensive Care Unit ◽

Neonatal Intensive Care ◽

Correlation Coefficients ◽

Impulse Radio ◽

Ultra Wideband ◽

Uwb Radar ◽

Impedance Pneumography ◽

Wideband Radar

Background Current cardiorespiratory monitoring equipment can cause injuries and infections in neonates with fragile skin. Impulse-radio ultra-wideband (IR-UWB) radar was recently demonstrated to be an effective contactless vital sign monitor in adults. The purpose of this study was to assess heart rates (HRs) and respiratory rates (RRs) in the neonatal intensive care unit (NICU) using IR-UWB radar and to evaluate its accuracy and reliability compared to conventional electrocardiography (ECG)/impedance pneumography (IPG). Methods The HR and RR were recorded in 34 neonates between 3 and 72 days of age during minimal movement (51 measurements in total) using IR-UWB radar (HRRd, RRRd) and ECG/IPG (HRECG, RRIPG) simultaneously. The radar signals were processed in real time using algorithms for neonates. Radar and ECG/IPG measurements were compared using concordance correlation coefficients (CCCs) and Bland-Altman plots. Results From the 34 neonates, 12,530 HR samples and 3,504 RR samples were measured. Both the HR and RR measured using the two methods were highly concordant when the neonates had minimal movements (CCC = 0.95 between the RRRd and RRIPG, CCC = 0.97 between the HRRd and HRECG). In the Bland-Altman plot, the mean biases were 0.17 breaths/min (95% limit of agreement [LOA] -7.0–7.3) between the RRRd and RRIPG and -0.23 bpm (95% LOA -5.3–4.8) between the HRRd and HRECG. Moreover, the agreement for the HR and RR measurements between the two modalities was consistently high regardless of neonate weight. Conclusions A cardiorespiratory monitor using IR-UWB radar may provide accurate non-contact HR and RR estimates without wires and electrodes for neonates in the NICU.

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Semicircular Patch-Embedded Vivaldi Antenna for Miniaturized UWB Radar Sensors

Sensors ◽

10.3390/s20215988 ◽

2020 ◽

Vol 20 (21) ◽

pp. 5988

Author(s):

Jungwoo Seo ◽

Jae Hee Kim ◽

Jungsuek Oh

Keyword(s):

Electric Fields ◽

Impedance Matching ◽

Low Frequency ◽

Electrical Fields ◽

Radar Sensors ◽

Gain Enhancement ◽

Uwb Radar ◽

Vivaldi Antenna ◽

Matching Techniques ◽

Good Agreement

A microstrip-to-slot line-fed miniaturized Vivaldi antenna using semicircular patch embedment is proposed in this study. The conventional Vivaldi antenna has ultrawide bandwidth, but suffers from low gain in the low-frequency band. The proposed antenna topology incorporates the embedment of semicircular patch elements into the side edge of the antenna. This enables the phases of electric fields at both ends of the antenna to be out of phase. Since the distance between the two ends are λL/2 where λL is the wavelength at a low operating frequency, this antenna topology can achieve the constructive addition of electrical fields at the radiating end, leading to gain enhancement at the chosen low frequency. In comparison with the conventional Vivaldi antenna, the proposed antenna has a wider bandwidth from 2.84 to 9.83 GHz. Moreover, the simulated result shows a gain enhancement of 5 dB at low frequency. This cannot be realized by the conventional low-band impedance matching techniques only relying on slotted topologies. The measured results of this proposed antenna with a size of 45 × 40 × 0.8 mm3 are in good agreement with the simulated results.

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Non-contact Sleep/Wake Monitoring Using Impulse-Radio Ultrawideband Radar in Neonates

Frontiers in Pediatrics ◽

10.3389/fped.2021.782623 ◽

2021 ◽

Vol 9 ◽

Author(s):

Won Hyuk Lee ◽

Seung Hyun Kim ◽

Jae Yoon Na ◽

Young-Hyo Lim ◽

Seok Hyun Cho ◽

...

Keyword(s):

Neonatal Intensive Care ◽

Vital Signs ◽

Behavioral Observation ◽

Impulse Radio ◽

Recording Time ◽

Decision Algorithm ◽

Uwb Radar ◽

Sensing Technology ◽

Movement Asymmetry ◽

Contact Sensing

Background: The gold standard for sleep monitoring, polysomnography (PSG), is too obtrusive and limited for practical use with tiny infants or in neonatal intensive care unit (NICU) settings. The ability of impulse-radio ultrawideband (IR-UWB) radar, a non-contact sensing technology, to assess vital signs and fine movement asymmetry in neonates was recently demonstrated. The purpose of this study was to investigate the possibility of quantitatively distinguishing and measuring sleep/wake states in neonates using IR-UWB radar and to compare its accuracy with behavioral observation-based sleep/wake analyses using video recordings.Methods: One preterm and three term neonates in the NICU were enrolled, and voluntary movements and vital signs were measured by radar at ages ranging from 2 to 27 days. Data from a video camcorder, amplitude-integrated electroencephalography (aEEG), and actigraphy were simultaneously recorded for reference. Radar signals were processed using a sleep/wake decision algorithm integrated with breathing signals and movement features.Results: The average recording time for the analysis was 13.0 (7.0–20.5) h across neonates. Compared with video analyses, the sleep/wake decision algorithm for neonates correctly classified 72.2% of sleep epochs and 80.6% of wake epochs and achieved a final Cohen's kappa coefficient of 0.49 (0.41–0.59) and an overall accuracy of 75.2%.Conclusions: IR-UWB radar can provide considerable accuracy regarding sleep/wake decisions in neonates, and although current performance is not yet sufficient, this study demonstrated the feasibility of its possible use in the NICU for the first time. This unobtrusive, non-contact radar technology is a promising method for monitoring sleep/wake states with vital signs in neonates.

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Repeatability of automated measurements by a new anterior segment optical coherence tomographer and biometer and agreement with standard devices

Scientific Reports ◽

10.1038/s41598-020-79674-4 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Domenico Schiano-Lomoriello ◽

Kenneth J. Hoffer ◽

Irene Abicca ◽

Giacomo Savini

Keyword(s):

Intraclass Correlation ◽

Anterior Segment ◽

Consecutive Series ◽

Optical Coherence ◽

Limits Of Agreement ◽

Automated Measurements ◽

Deviation Coefficient ◽

Corneal Diameter ◽

High Repeatability ◽

Good Agreement

AbstractWe assess repeatability of automatic measurements of a new anterior segment optical coherence tomographer and biometer (ANTERION) and their agreement with those provided by an anterior segment-optical coherence tomography device combined with Placido-disk corneal topography (MS-39) and a validated optical biometer (IOLMaster 500). A consecutive series of patients underwent three measurements with ANTERION and one with MS-39. A subgroup of patients underwent biometry also with IOLMaster 500. Repeatability was assessed by means of within-subject standard deviation, coefficient of variation (COV), and intraclass correlation coefficient (ICC). Agreement was investigated with the 95% limits of agreement. Paired t-test and Wilcoxon matched-pairs test were performed to compare the measurements of the different devices. Repeatability of ANTERION measurements was high, with ICC > 0.98 for all parameters except astigmatism (0.963); all parameters apart from those related to astigmatism revealed a COV < 1%. Repeatability of astigmatism improved when only eyes whose keratometric astigmatism was higher than 1.0 D were investigated. Most measurements by ANTERION and MS-39 showed good agreement. No significant differences were found between measurements by ANTERION and IOLMaster, but for corneal diameter. ANTERION revealed high repeatability of automatic measurements and good agreement with both MS-39 and IOLMaster for most parameters.

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Agreement and reliability of magnetic, angular rate, and gravity (MARG) sensors to assess multiple body segment’s external loads during off-road running

Proceedings of the Institution of Mechanical Engineers Part P Journal of Sports Engineering and Technology ◽

10.1177/1754337121996986 ◽

2021 ◽

pp. 175433712199698

Author(s):

Daniel Rojas-Valverde ◽

José Pino-Ortega ◽

Rafael Timón ◽

Randall Gutiérrez-Vargas ◽

Braulio Sánchez-Ureña ◽

...

Keyword(s):

Vastus Lateralis ◽

Angular Rate ◽

Wearable Sensors ◽

Intraclass Correlation ◽

Principal Component ◽

Test Reliability ◽

Data Set ◽

Body Segments ◽

External Loads ◽

Good Agreement

The extensive use of wearable sensors in sport medicine, exercise medicine, and health has increased the interest in their study. That is why it is necessary to test these technologies’ efficiency, effectiveness, agreement, and reliability in different settings. Consequently, the purpose of this article was to analyze the magnetic, angular rate, and gravity (MARG) sensor’s test-retest agreement and reliability when assessing multiple body segments’ external loads during off-road running. A total of 18 off-road runners (38.78 ± 10.38 years, 73.24 ± 12.6 kg, 172.17 ± 9.48 cm) ran two laps (1st and 2nd Lap) of a 12 km circuit wearing six MARG sensors. The sensors were attached to six different body segments: left (MPLeft) and right (MPRight) malleolus peroneus, left (VLLeft) and right (VLRight) vastus lateralis, lumbar (L1-L3), and thorax (T2-T4) using a special neoprene suit. After a principal component analysis (PCA) was performed, the total data set variance of all body segments was represented by 44.08%–70.64% for the 1st PCA factor considering two variables, Player LoadRT and Impacts, on L1-L3, respectively. These two variables were chosen among three total accelerometry-based external load indicators (ABELIs) to perform the agreement and reliability tests due to their relevance based on PCAs for each body segment. There were no significant differences between laps in the Player LoadRT or Impacts ( p > 0.05, trivial). The intraclass correlation and lineal correlation showed a substantial to almost perfect over-time test consistency assessed via reliability in both Player LoadRT and Impacts. Bias and t-test assessments showed good agreement between Laps. It can be concluded that MARGs sensors offer significant test re-test reliability and good agreement when assessing off-road kinematics in the six different body segments.

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251 Agreement and reliability of a new polysomnography sleep staging algorithm against multiple human scorers

SLEEP ◽

10.1093/sleep/zsab072.250 ◽

2021 ◽

Vol 44 (Supplement_2) ◽

pp. A101-A101

Author(s):

Ulysses Magalang ◽

Brendan Keenan ◽

Bethany Staley ◽

Peter Anderer ◽

Marco Ross ◽

...

Keyword(s):

Total Sleep Time ◽

High Reliability ◽

Sleep Stage ◽

Intraclass Correlation ◽

Sleep Time ◽

Sleep Staging ◽

Original Dataset ◽

Scoring Algorithm ◽

Scoring Algorithms ◽

Good Agreement

Abstract Introduction Scoring algorithms have the potential to increase polysomnography (PSG) scoring efficiency while also ensuring consistency and reproducibility. We sought to validate an updated sleep staging algorithm (Somnolyzer; Philips, Monroeville PA USA) against manual sleep staging, by analyzing a dataset we have previously used to report sleep staging variability across nine center-members of the Sleep Apnea Global Interdisciplinary Consortium (SAGIC). Methods Fifteen PSGs collected at a single sleep clinic were scored independently by technologists at nine SAGIC centers located in six countries, and auto-scored with the algorithm. Each 30-second epoch was staged manually according to American Academy of Sleep Medicine criteria. We calculated the intraclass correlation coefficient (ICC) and performed a Bland-Altman analysis comparing the average manual- and auto-scored total sleep time (TST) and time in each sleep stage (N1, N2, N3, rapid eye movement [REM]). We hypothesized that the values from auto-scoring would show good agreement and reliability when compared to the average across manual scorers. Results The participants contributing to the original dataset had a mean (SD) age of 47 (12) years and 80% were male. Auto-scoring showed substantial (ICC=0.60-0.80) or almost perfect (ICC=0.80-1.00) reliability compared to manual-scoring average, with ICCs (95% confidence interval) of 0.976 (0.931, 0.992) for TST, 0.681 (0.291, 0.879) for time in N1, 0.685 (0.299, 0.881) for time in N2, 0.922 (0.791, 0.973) for time in N3, and 0.930 (0.811, 0.976) for time in REM. Similarly, Bland-Altman analyses showed good agreement between methods, with a mean difference (limits of agreement) of only 1.2 (-19.7, 22.0) minutes for TST, 13.0 (-18.2, 44.1) minutes for N1, -13.8 (-65.7, 38.1) minutes for N2, -0.33 (-26.1, 25.5) minutes for N3, and -1.2 (-25.9, 23.5) minutes for REM. Conclusion Results support high reliability and good agreement between the auto-scoring algorithm and average human scoring for measurements of sleep durations. Auto-scoring slightly overestimated N1 and underestimated N2, but results for TST, N3 and REM were nearly identical on average. Thus, the auto-scoring algorithm is acceptable for sleep staging when compared against human scorers. Support (if any) Philips.

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Should We Base Training Prescription on the Force–Velocity Profile? Exploratory Study of Its Between-Day Reliability and Differences Between Methods

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2020-0308 ◽

2020 ◽

pp. 1-7

Author(s):

Pedro L. Valenzuela ◽

Guillermo Sánchez-Martínez ◽

Elaia Torrontegi ◽

Javier Vázquez-Carrión ◽

Zigor Montalvo ◽

...

Keyword(s):

Coefficient Of Variation ◽

Intraclass Correlation ◽

Reliability Coefficient ◽

Power Coefficient ◽

Squat Jump ◽

Jump Test ◽

Force Velocity ◽

Constrained Conditions ◽

Vertical Jumps ◽

Good Agreement

Purpose: To analyze the differences in the force–velocity (F–v) profile assessed under unconstrained (ie, using free weights) and constrained (ie, on a Smith machine) vertical jumps, as well as to determine the between-day reliability. Methods: A total of 23 trained participants (18 [1] y) performed an incremental load squat jump test (with ∼35%, 45%, 60%, and 70% of the subjects’ body mass) on 2 different days using free weights and a Smith machine. Nine of these participants repeated the tests on 2 other days for an exploratory analysis of between-day reliability. F–v variables (ie, maximum theoretical force [F0], velocity [v0], and power, and the imbalance between the actual and the theoretically optimal F–v profile) were computed from jump height. Results: A poor agreement was observed between the F–v variables assessed under constrained and unconstrained conditions (intraclass correlation coefficient [ICC] < .50 for all). The height attained during each single jump performed under both constrained and unconstrained conditions showed an acceptable reliability (coefficient of variation < 10%, ICC > .70). The F–v variables computed under constrained conditions showed an overall good agreement (ICC = .75–.95 for all variables) and no significant differences between days (P > .05), but a high variability for v0, the imbalance between the actual and the theoretically optimal F–v profile, and maximal theoretical power (coefficient of variation = 17.0%–27.4%). No between-day differences were observed for any F–v variable assessed under unconstrained conditions (P > .05), but all of the variables presented a low between-day reliability (coefficient of variation > 10% and ICC < .70 for all). Conclusions: F–v variables differed meaningfully when obtained from constrained and unconstrained loaded jumps, and most importantly seemed to present a low between-day reliability.

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Reproducibility and validity of portable haemoglobinometer for the diagnosis of anaemia in children under the age of 5 years

Journal of Nutritional Science ◽

10.1017/jns.2019.43 ◽

2020 ◽

Vol 9 ◽

Author(s):

Alessandra da Silva Pereira ◽

Inês Rugani Ribeiro de Castro ◽

Flávia Fioruci Bezerra ◽

José Firmino Nogueira Neto ◽

Ana Carolina Feldenheimer da Silva

Keyword(s):

Venous Blood ◽

Intraclass Correlation ◽

Age Groups ◽

Capillary Blood ◽

Test Method ◽

Automated System ◽

Accuracy Rate ◽

Predictive Values ◽

Sensitivity Specificity ◽

Good Agreement

Abstract Portable haemoglobinometers have been used in order to estimate the prevalence of anaemia in diverse settings. However, few studies have been conducted to evaluate their performance in children of different age groups in distinct epidemiological contexts. To evaluate the reproducibility and reliability of a portable haemoglobinometer for the diagnosis of anaemia in children <5 years Hb was measured in the venous blood of 351 children <5 years by an automated system (standard method) and in three capillary blood samples, using a portable haemoglobinometer (HemoCue®; test method). The reproducibility of the device and of the test method was evaluated using the intraclass correlation coefficient (ICC) (Hb in its continuous form), κ and prevalence-adjusted bias-adjusted κ (PABAK) (categorised variable: anaemia: yes/no). For test method validation, Bland–Altman analyses were performed and sensitivity, specificity, accuracy rate, positive predictive value (PPV) and negative predictive values (NPV) were calculated. The haemoglobinometer presented good device reproducibility (ICC = 0·79) and reasonable method reproducibility (puncture, collection and reading) (ICC = 0·71). Superficial and fair agreement (κ) and good agreement (PABAK) were observed among the diagnoses obtained through the test method. The prevalence of anaemia was 19·1 and 19·7 % using the standard and the test method, respectively, with no statistically significant differences. The test method presented higher specificity (87·7 %) and NPV (88·3 %) than sensitivity (50·7 %) and PPV (49·3 %), and intermediary accuracy rate (57·8 %). HemoCue® showed good device reproducibility and reasonable method reproducibility, as well as good performance in estimating the prevalence of anaemia. Nevertheless, it showed a fair reliability and low individual diagnostic accuracy.

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Non-Contact Video-Based Neonatal Respiratory Monitoring

Children ◽

10.3390/children7100171 ◽

2020 ◽

Vol 7 (10) ◽

pp. 171

Author(s):

Scott L. Rossol ◽

Jeffrey K. Yang ◽

Caroline Toney-Noland ◽

Janine Bergin ◽

Chandan Basavaraju ◽

...

Keyword(s):

Neonatal Intensive Care ◽

Continuous Monitoring ◽

Improve Patient Care ◽

Neonatal Intensive Care Units ◽

P Value ◽

Monitoring Methods ◽

Iatrogenic Complications ◽

Impedance Pneumography ◽

Clinical Changes ◽

Improve Patient

Respiratory rate (RR) has been shown to be a reliable predictor of cardio-pulmonary deterioration, but standard RR monitoring methods in the neonatal intensive care units (NICU) with contact leads have been related to iatrogenic complications. Video-based monitoring is a potential non-contact system that could improve patient care. This iterative design study developed a novel algorithm that produced RR from footage analyzed from stable NICU patients in open cribs with corrected gestational ages ranging from 33 to 40 weeks. The final algorithm used a proprietary technique of micromotion and stationarity detection (MSD) to model background noise to be able to amplify and record respiratory motions. We found significant correlation—r equals 0.948 (p value of 0.001)—between MSD and the current hospital standard, electrocardiogram impedance pneumography. Our video-based system showed a bias of negative 1.3 breaths and root mean square error of 6.36 breaths per minute compared to standard continuous monitoring. Further work is needed to evaluate the ability of video-based monitors to observe clinical changes in a larger population of patients over extended periods of time.

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Prehospital Vital Signs Accurately Predict Initial Emergency Department Vital Signs

Prehospital and Disaster Medicine ◽

10.1017/s1049023x2000028x ◽

2020 ◽

Vol 35 (3) ◽

pp. 254-259

Author(s):

Marc D. Trust ◽

Morgan Schellenberg ◽

Subarna Biswas ◽

Kenji Inaba ◽

Vincent Cheng ◽

...

Keyword(s):

Emergency Department ◽

Intraclass Correlation ◽

Vital Signs ◽

Correlation Coefficients ◽

Trauma Team ◽

Urban Setting ◽

Trauma Patients ◽

Level I ◽

Gcs Score ◽

Good Agreement

AbstractIntroduction:Prehospital vital signs are used to triage trauma patients to mobilize appropriate resources and personnel prior to patient arrival in the emergency department (ED). Due to inherent challenges in obtaining prehospital vital signs, concerns exist regarding their accuracy and ability to predict first ED vitals.Hypothesis/Problem:The objective of this study was to determine the correlation between prehospital and initial ED vitals among patients meeting criteria for highest levels of trauma team activation (TTA). The hypothesis was that in a medical system with short transport times, prehospital and first ED vital signs would correlate well.Methods:Patients meeting criteria for highest levels of TTA at a Level I trauma center (2008-2018) were included. Those with absent or missing prehospital vital signs were excluded. Demographics, injury data, and prehospital and first ED vital signs were abstracted. Prehospital and initial ED vital signs were compared using Bland-Altman intraclass correlation coefficients (ICC) with good agreement as >0.60; fair as 0.40-0.60; and poor as <0.40).Results:After exclusions, 15,320 patients were included. Mean age was 39 years (range 0-105) and 11,622 patients (76%) were male. Mechanism of injury was blunt in 79% (n = 12,041) and mortality was three percent (n = 513). Mean transport time was 21 minutes (range 0-1,439). Prehospital and first ED vital signs demonstrated good agreement for Glasgow Coma Scale (GCS) score (ICC 0.79; 95% CI, 0.77-0.79); fair agreement for heart rate (HR; ICC 0.59; 95% CI, 0.56-0.61) and systolic blood pressure (SBP; ICC 0.48; 95% CI, 0.46-0.49); and poor agreement for pulse pressure (PP; ICC 0.32; 95% CI, 0.30-0.33) and respiratory rate (RR; ICC 0.13; 95% CI, 0.11-0.15).Conclusion:Despite challenges in prehospital assessments, field GCS, SBP, and HR correlate well with first ED vital signs. The data show that these prehospital measurements accurately predict initial ED vitals in an urban setting with short transport times. The generalizability of these data to settings with longer transport times is unknown.

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