RESUMEN
BACKGROUND: Muscle mass and phase angle (PhA) can be measured using multi-frequency bioelectrical impedance analysis (BIA). Osteoarthritis of the hip (OAhip) causes decreased muscle mass and PhA in the deformed lower limb. However, previous studies have not accounted for the influence of sex, and thus, the relationship between muscle mass, PhA, and motor function remains unclear. This study aimed to elucidate the relationship between PhA, an index of muscle mass and quality measured using BIA, and motor function during gait and standing in female patients with OAhip. METHODS: Muscle mass and PhA of patients with OAhip were measured using BIA. Motor function was evaluated using the Timed Up and Go test, ground reaction/weight, rate of force development/weight, and load ratio between the osteoarthritic (OA) and contralateral sides when standing up. The difference between the OA side and the contralateral lower limb was tested to clarify the characteristics of the deformed lower limb. The relationship between each motor function was determined using a partial correlation coefficient with age as a control variable and multiple regression analysis with each motor function as the dependent variable and age, OA-side muscle mass/body weight ratio, and PhA as independent variables. RESULTS: This study involved 60 patients with OAhip (age 65.6 ± 7.6 years, height 154.2 ± 6.0 cm, weight 56.8 ± 10.5 kg) scheduled for unilateral total hip arthroplasty. Muscle mass, PhA, and lower limb load ratio were significantly decreased in the lower limbs on the OA side. Furthermore, using a partial correlation coefficient with age as a control variable, PhA showed significant correlations with motor functions related to standing up and walking, and multiple regression analysis revealed that PhA was independently related to each motor function. CONCLUSIONS: Evaluation and interventions that consider muscle quality rather than muscle mass are important.
Asunto(s)
Extremidad Inferior , Músculo Esquelético , Osteoartritis de la Cadera , Humanos , Femenino , Osteoartritis de la Cadera/fisiopatología , Estudios Transversales , Anciano , Músculo Esquelético/fisiopatología , Extremidad Inferior/fisiopatología , Persona de Mediana Edad , Marcha/fisiología , Impedancia Eléctrica , Actividad Motora/fisiologíaRESUMEN
Compared to traditional unipolar radiofrequency ablation (RFA), bipolar RFA offers advantages such as more precise heat transfer and higher ablation efficiency. Clinically, myocardial baseline impedance (BI) is one of the important factors affecting the effectiveness of ablation. We aim at finding suitable ablation protocols and coping strategies by analyzing the ablation effects and myocardial impedance changes of bipolar RFA under different BIs. In this research, a three-dimensional local myocardial computer model was constructed for bipolar RFA simulation, and in vitro experimental data were used to validate accuracy. Four fixed low-power levels (20 W, 25 W, 30 W, and 35 W) and six myocardial BIs (91.02 Ω, 99.83 Ω, 111.03 Ω, 119.77 Ω, 130.03 Ω, and 135.45 Ω) were set as initial conditions, with an ablation duration of 120-s. In the context of low-power and long-duration (LPLD) ablation, the maximum TID (TIDM) decreased by 21-32 Ω, depending on the BI. In cases where steam pop did not occur, TIDM increased with the increase in power. For the same power, there was no significant difference in TIDM for the range of BIs. In cases where steam pop occurred, for every 1 Ω increase in BI, TIDM increased by 0.34-0.41 Ω. The simulation results also showed that using a higher power resulted in a smaller decrease in TIDM. This study provided appropriate ablation times and impedance decrease ranges for bipolar LPLD RFA. The combination of 25 W for 120-s offered optimal performance when considering effectiveness and safety simultaneously.
Asunto(s)
Simulación por Computador , Impedancia Eléctrica , Ablación por Radiofrecuencia , Ablación por Radiofrecuencia/métodos , Factores de Tiempo , Humanos , CorazónRESUMEN
In this study, the free space approach is utilized to calculate the relative permittivity of FR4 by utilizing the Nicholson-Ross-Weir Conversion. By examining the scattering characteristics, the free space technique offers a practical tool for describing dielectric materials. The simulations were run on CST-2019, and the frequency range of 8.5 GHz to 11.5 GHz was chosen. Experimental measurements were carried out utilizing a Vector Network Analyzer, To further reduce outside influences and assure accurate measurements in a controlled setting, an anechoic chamber was used. The outcomes of the simulations and actual measurements show the significance of the Nicholson- Ross-Weir Conversion and free space approach in calculating the relative permittivity of FR4. The correctness and dependability of the suggested technique are confirmed by the good agreement between the simulated and measured outcomes. This study makes a contribution to the field of electromagnetic characterization and offers a useful method for figuring out FR4's dielectric characteristics. The results of this study have substantial effects on PCB design and optimization as well as other high-frequency electronic devices that operate in the frequency band under consideration.
Asunto(s)
Simulación por Computador , Modelos Teóricos , Impedancia EléctricaRESUMEN
OBJECTIVE: Ultra-processed foods (UPF) and minimally processed foods (MPF) consumption are differentially connected to adiposity and possibly body composition. Phase angle (PhA) originates from bioelectrical impedance analysis (BIA) and is connected to cellular health. This study is the first to investigate associations between UPF/MPF consumption and PhA. DESIGN: A cross-sectional study was conducted. Anthropometrical and BIA were performed. The Hellenic Physical Activity Questionnaire was used for physical activity evaluation, while a validated FFQ was used for dietary assessment. UPF and MPF intake (% energy) were determined according to the NOVA system. Partial correlation coefficients of PhA and dietary variables were assessed after multi-adjustment. PARTICIPANTS: Students were recruited (n 151, 114 women). SETTING: University. RESULTS: Median and interquartile range (IQR) of PhA were 5·5° (5·1-6·4°) in the total sample, 6·8° (6·1-7·3°) in men and 5·3° (5·1-5·9°) in women (P < 0·001). The median and IQR for UPF consumption was 13·7 (8·1-33·4) % in the total sample, 23·8 (8·1-70·5) % in men and 12·9 (8·1-27·5) % in women (P < 0·001). The mean (sd) of MPF consumption was 60·2 (sd 15·7) % for the total sample, 59·1 (sd 16·4) % for men and 60·5 (sd 15·6) % for women (P = 0·720). The consumption of UPF was negatively (rho = -0·267, P = 0·002), while the consumption of MPF was positively (rho = 0·218, P = 0·010) associated with the PhA, after adjustment for age, sex, BMI and physical activity. CONCLUSION: PhA relates inversely to UPF and positively to MPF consumption. The observed associations possibly reflect the effects of diet on cellular health and in turn PhA.
Asunto(s)
Dieta , Comida Rápida , Manipulación de Alimentos , Estudiantes , Humanos , Femenino , Estudios Transversales , Masculino , Estudiantes/estadística & datos numéricos , Adulto Joven , Universidades , Comida Rápida/estadística & datos numéricos , Dieta/estadística & datos numéricos , Adulto , Impedancia Eléctrica , Composición Corporal , Ejercicio Físico , Encuestas y Cuestionarios , Adiposidad , Adolescente , Conducta Alimentaria , Alimentos ProcesadosRESUMEN
Live-cell label-free imaging of a microscopic biological barrier, generally referred to as 'tight junction', was realized by a recently developed electric-double-layer modulation imaging (EDLMI). The method allowed quantitative imaging of barrier integrity in real time, thus being an upper compatible of transepithelial electrical resistance (TEER) which is a conventional standard technique to evaluate spatially averaged barrier integrity. We demonstrate that the quantitative and real-time imaging capability of EDLMI unveils fundamental dynamics of biological barrier, some of which are totally different from conventional understandings.
Asunto(s)
Técnicas Biosensibles , Humanos , Técnicas Biosensibles/métodos , Uniones Estrechas/metabolismo , Impedancia EléctricaRESUMEN
OBJECTIVES: The aim of this investigation was to evaluate the discrepancies between bioelectrical impedance analysis (BIA) and computed tomography (CT) in assessing skeletal muscle mass and identifying low muscle mass in patients with colorectal cancer. METHODS: This study recruited 137 patients with colorectal cancer from February 2028 to December 2023. CT scans were analyzed at the Lumbar 3 vertebral level to determine the area of skeletal muscle, which was then utilized to estimate whole-body skeletal muscle mass. [BIA] was also employed to measure skeletal muscle. Both skeletal muscle mass values [kg] were divided by height2 [m2] to calculate the skeletal muscle index [SMI, kg/m2], denoted as SMI-CT and SMI-BIA, respectively. RESULTS: The median age was 69.8 + 9.5 years, with the sex ratio being 88/49 [male/female]. Whereas more than one-third of the patients were classified as malnourished based on the Global Leadership Initiative on Malnutrition GLIM-CT criteria using L3-SMI [n = 36.5%], fewer patients were classified as malnourished based on GLIM-BIA using SMI-BIA [n = 19.0%]. According to the CT analysis [low SMI-L3], 52 [38.0%] patients were diagnosed as having poor muscle mass, whereas only 18 [13.1%] patients were identified as having low muscle mass using BIA [low SMIBIA]. The measured SMI showed a positive association with SMI-CT in all patients [r = 0.63, p < 0.001]. Using Bland-Altman evaluation, a significant mean bias of 0.45 + 1.41 kg/m2 [95% CI 0.21-0.70; p < 0.001] between SMI-BIA and SMI-CT was reported. Receiver operating characteristic (ROC) curves were generated to detect poor muscle mass using SMI-BIA with CT as the gold standard. The area under the curve (AUC) for SMI-BIA in identifying poor muscle mass was 0.714 (95% CI: 0.624-0.824), with a good cut-off value of 8.1 kg/m2, yielding a sensitivity of 68.3% and a specificity of 66.9%. CONCLUSIONS: BIA generally overestimates skeletal muscle mass in colorectal cancer patients when contrasted to CT. As a result, BIA may underestimate the prevalence of poor muscle mass and malnutrition according to the GLIM criteria in this patient population.
Asunto(s)
Composición Corporal , Neoplasias Colorrectales , Impedancia Eléctrica , Desnutrición , Músculo Esquelético , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Neoplasias Colorrectales/complicaciones , Neoplasias Colorrectales/diagnóstico por imagen , Anciano , Desnutrición/diagnóstico , Desnutrición/epidemiología , Tomografía Computarizada por Rayos X/métodos , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiopatología , Persona de Mediana Edad , Sarcopenia/diagnóstico por imagen , Sarcopenia/diagnóstico , Evaluación Nutricional , Estado Nutricional , Anciano de 80 o más AñosRESUMEN
Despite BIA emerging as a clinical tool for assessing older adults, it remains unclear how to calculate whole-body impedance (Z), reactance (Xc), resistance (R), and phase angle (PhA) from segmental values using modern BIA devices that place electrodes on both sides of the body. This investigation aimed to compare both the whole-body and segmental device-generated phase angle (PhADG) with the phase angle calculated using summed Z, Xc, and R from the left, right, and combined sides of the body (PhACalc) and to compare bioelectric variables between sides of the body. A sample of 103 community-dwelling older adults was assessed using a 50 kHz direct segmental multifrequency BIA device. Whole-body PhACalc values were assessed for agreement with PhADG using 2.5th and 97.5th quantile nonparametric limits of agreement and Spearman's rho. Bioelectrical values between sides of the body were compared using Wilcoxon rank and Spearman's rho. A smaller mean difference was observed between PhADG and right PhACalc (-0.004°, p = 0.26) than between PhACalc on the left (0.107°, p = 0.01) and on the combined sides (0.107°, p < 0.001). The sum of Z, R, and PhACalc was significantly different (p < 0.01) between the left (559.66 ± 99.55 Ω, 556.80 ± 99.52 Ω, 5.51 ± 1.5°, respectively) and the right sides (554.60 ± 94.52 Ω, 552.02 ± 94.23 Ω, 5.41 ± 0.8°, respectively). Bilateral BIA values do not appear to be interchangeable when determining whole-body measurements. Present data suggest that using right-sided segmental values would be the most appropriate choice for calculating whole-body bioelectrical variables.
Asunto(s)
Impedancia Eléctrica , Vida Independiente , Humanos , Anciano , Masculino , Femenino , Anciano de 80 o más Años , Composición Corporal/fisiologíaRESUMEN
BACKGROUND: The objective is to assess lung compliance and identify the optimal positive end-expiratory pressure (PEEP) levels in patients with tuberculosis-associated Acute Respiratory Distress Syndrome (TB-ARDS) compared to non-TB-ARDS patients. METHODS: This observational case-control study utilized electrical impedance tomography to evaluate lung mechanics in 20 TB-ARDS and 20 non-TB-ARDS patients. Participants underwent PEEP titration from 23 to 5 cm H2O in 2 cm H2O decrements. Lung compliance and the rates of hyperdistention and collapse were assessed at each PEEP level. RESULTS: Delta impedance values showed higher amounts in a PEEP range of 11-17 cm H2O and in patients with TB-ARDS (P > 0.05). In addition, both hyperdistention and collapse rates were nonsignificantly higher in TB-ARDS patients (P > 0.05), and the compromised levels of hyperdistention and collapse rates were at 15-17 cm H2O, indicating the most favorable PEEP level. CONCLUSIONS: The observed patterns of hyperdistention and collapse rates across various PEEP levels provide valuable insights into the susceptibility of TB-ARDS patients to barotrauma. Notably, the identified optimal PEEP range between 15 and 17 cm H2O may guide ventilator management strategies in mitigating both hyperdistention and collapse; nonetheless, due to the high variability of lung compliances within groups, we strongly recommend individualized consideration for tailored respiratory support and evaluation.
Asunto(s)
Respiración con Presión Positiva , Síndrome de Dificultad Respiratoria , Humanos , Síndrome de Dificultad Respiratoria/terapia , Síndrome de Dificultad Respiratoria/fisiopatología , Masculino , Estudios de Casos y Controles , Femenino , Persona de Mediana Edad , Adulto , Impedancia Eléctrica , Tuberculosis Pulmonar/complicaciones , Tuberculosis Pulmonar/fisiopatología , Tuberculosis/complicaciones , Anciano , Pulmón/fisiopatología , Rendimiento PulmonarRESUMEN
Different pathological changes in the large intestine wall, associated with the development of different chronic diseases, including colorectal cancer, could be reflected in electrical bioimpedance readings. Thickness and composition of the mucus bilayer covering it in the luminal side, abundance of bacteria of the intestinal microbiota, the permeability of the epithelium and inflammation are some of these. However, scientific literature on electrical passive properties of the large intestine is scarce. In this study, complex impedance measurements at 8 frequencies were carried out on 6 specimens of porcine colorectal tissue, within half ab hour post-mortem, obtained from a local abattoir. For 5 different distances, measured proximally from the border of the anus, 3 readings were taken at 3 different points with a tetrapolar probe. The results show 2 different dielectric dispersions in the α and ß regions and it seems that there is a relationship between the values of resistivities and the thickness of the wall. Also, parameter values both for the Cole and the geometrical models are given. Another set of electrical bioimpedance readings was carried out in order to assess the effect of the mucus layer on electrical properties of the tissue. It seems that these layers are related to the low frequency dispersion. Finally, electrical passive properties of porcine colorectal tissue, reported in this work, give reference values and behaviour patterns that could be applied for further research in human medicine, based on bioimpedance measurements.
Asunto(s)
Colon , Impedancia Eléctrica , Recto , Animales , Porcinos , Recto/fisiología , Colon/fisiologíaRESUMEN
OBJECTIVES: The aim of this study was to evaluate body composition variability assessed by bioimpedance in relation to nutritional status assessed by anthropometry in children and adolescents living in countries characterized by contrasting nutritional conditions. METHODS: The sample was comprised of 8614 children (4245 males; 4369 females), aged 3 to 19 years, from Nepal (477 children), Uganda (488 children and adolescents), UK (297 children and adolescents) and US (7352 children and adolescents). Height-for-age (HAZ) and body mass index-for-age (BAZ) z-scores were calculated according to WHO growth references. Specific bioelectrical impedance vector analysis (BIVA) was used to evaluate body composition variability. In each population sample, the relationship of HAZ and BAZ with bioelectrical outcomes was analysed by confidence ellipses and cubic spline regression, controlling for sex and age. RESULTS: The participants from Uganda and Nepal were more affected by undernutrition, and those from the US and UK by obesity. In all groups, phase angle and specific vector length were weakly associated with HAZ, with null or opposite relationships in the different samples, whereas they were positively associated with BAZ. The stronger association was between vector length, indicative of the relative content of fat mass, and BAZ in the UK and US samples. Confidence ellipses showed that the relationships are more strongly related to phase angle in Nepalese and Ugandan samples. CONCLUSIONS: Bioelectrical values were more strongly associated with BAZ than HAZ values in all population samples. Variability was more related to markers of muscle mass in Ugandan and Nepalese samples and to indicators of fat mass in UK and US samples. Specific BIVA can give information on the variability of body composition in malnourished individuals.
Asunto(s)
Antropometría , Composición Corporal , Índice de Masa Corporal , Impedancia Eléctrica , Desnutrición , Estado Nutricional , Humanos , Femenino , Masculino , Niño , Uganda , Adolescente , Desnutrición/epidemiología , Desnutrición/diagnóstico , Preescolar , Adulto Joven , Nepal , Reino Unido , Antropometría/métodos , Estados Unidos , Estatura , Obesidad/fisiopatologíaRESUMEN
The accurate determination of the post-dilution concentration of biological buffers is essential for retaining the necessary properties and effectiveness of the buffer to maintain stable cellular environments and optimal conditions for biochemical reactions. In this work, we introduce a silicon-based impedance chip, which offers a rapid and reagent-free approach for monitoring the buffer concentrations after dilution with deionized (DI) water. The impedance of the impedance chip is measured, and the impedance data are modeled using a multiparameter equivalent circuit model. We investigated six aqueous biological buffers with pH values above and below the physiological pH for most tissues (pH ~ 7.2-7.4) following dilution with DI water by factors of 2.0, 10.0, 20.0, 100.0, and 200.0. The impedance measurement is then performed for the frequency spectrum of 40 Hz to 1 MHz. From the interpretation of the impedance measurement using the multiparameter equivalent circuit model, we report a buffer-sensitive equivalent circuit parameter RAu/Si of the silicon-based impedance chip showing a linear trend on a logarithmic scale with the buffer concentration change after dilution. The parameter RAu/Si is independent of the buffer pH and the added volume. The results demonstrate the efficacy of the silicon-based impedance chip as a versatile tool for precise post-dilution concentration determination of diverse biologically relevant buffers. The presented impedance chip offers rapid, accurate, and reliable monitoring, making it highly suitable for integration into automated liquid-handling systems to enhance the efficiency and precision of biological and chemical processes.
Asunto(s)
Impedancia Eléctrica , Concentración de Iones de Hidrógeno , Tampones (Química) , Silicio/química , Soluciones/química , Técnicas Biosensibles/métodos , Agua/químicaRESUMEN
The assessment of athletic performance using non-invasive methods has been a significant focus in research aimed at measuring physiological parameters. This study explores the application of bioelectrical impedance vector analysis (BIVA) among track and field athletes, with a focus on sex differences, electrode configuration, and the correlation between BIVA parameters and jump performances. This cross-sectional study involved 61 Italian track and field athletes: 31 females and 30 males (age: 21.4 ± 3.8; 21.1 ± 2.6 years; stature: 166.1 ± 6.1; 180.1 ± 5.0 cm; body mass: 57.4 ± 9.7; 72.5 ± 10.5 kg, respectively). Anthropometric measurements, bioelectrical impedance analysis, and athletic jump performance were conducted. The RXc graph, two-sample Hotelling's T2 test for BIVA, and one-way ANOVA for specialty comparisons were employed. Pearson and Spearman's tests evaluated the correlations between BIVA parameters and jump performance. Differences in bioimpedance values were observed between athlete groups. Lateral asymmetries were more pronounced in females. Correlations between BIVA and jump performance also varied by sex and electrode configuration, ranging from r = -0.072, p = 0.699-r = 0.555, p = 0.001 in females, and from r = 0.204, p = 0.281-r = 0.691, p = 0.001 in males. This study highlights the utility of BIVA in providing rapid and non-invasive assessments of body composition and its relationship with jump performance, considering variations in athlete sex and electrode configuration.
Asunto(s)
Rendimiento Atlético , Impedancia Eléctrica , Atletismo , Humanos , Femenino , Masculino , Rendimiento Atlético/fisiología , Adulto Joven , Atletismo/fisiología , Adulto , Estudios Transversales , Caracteres Sexuales , Atletas , Electrodos , Composición Corporal/fisiologíaRESUMEN
The force developed by actively lengthened muscle depends on different structures across different scales of lengthening. For small perturbations, the active response of muscle is well captured by a linear-time-invariant (LTI) system: a stiff spring in parallel with a light damper. The force response of muscle to longer stretches is better represented by a compliant spring that can fix its end when activated. Experimental work has shown that the stiffness and damping (impedance) of muscle in response to small perturbations is of fundamental importance to motor learning and mechanical stability, while the huge forces developed during long active stretches are critical for simulating and predicting injury. Outside of motor learning and injury, muscle is actively lengthened as a part of nearly all terrestrial locomotion. Despite the functional importance of impedance and active lengthening, no single muscle model has all these mechanical properties. In this work, we present the viscoelastic-crossbridge active-titin (VEXAT) model that can replicate the response of muscle to length changes great and small. To evaluate the VEXAT model, we compare its response to biological muscle by simulating experiments that measure the impedance of muscle, and the forces developed during long active stretches. In addition, we have also compared the responses of the VEXAT model to a popular Hill-type muscle model. The VEXAT model more accurately captures the impedance of biological muscle and its responses to long active stretches than a Hill-type model and can still reproduce the force-velocity and force-length relations of muscle. While the comparison between the VEXAT model and biological muscle is favorable, there are some phenomena that can be improved: the low frequency phase response of the model, and a mechanism to support passive force enhancement.
Asunto(s)
Modelos Biológicos , Músculo Esquelético/fisiología , Fenómenos Biomecánicos , Humanos , Contracción Muscular/fisiología , Animales , Sarcómeros/fisiología , Impedancia EléctricaRESUMEN
The role of torso computed tomography (CT) in evaluating body composition has been unexplored. This study assessed the potential of low-dose torso CT from positron emission tomography (PET)/CT for analyzing body composition and its relation to muscle strength. We retrospectively recruited 384 healthy Korean adults (231 men, 153 women) who underwent torso 18F-FDG PET/CT, bioelectrical impedance analysis (BIA), and muscle strength tests (handgrip strength [HGS] and knee extension strength [KES]). CT images were segmented into three compartments: torso volumetric, abdominal volumetric, and abdominal areal. Muscle amounts from each compartment were indexed to height (m2). BIA and HGS served as reference standards, with correlation coefficients (r) calculated. Torso muscle volumetric index (TorsoMVI) had the strongest correlations with BIA-derived values (r = 0.80 for men; r = 0.73 for women), surpassing those from the abdominal compartments. TorsoMVI was also correlated significantly with HGS (r = 0.39, p < 0.01) and differentiated between normal and possible sarcopenia in men (n = 225, 5960 ± 785 cm3/m2 vs. n = 6, 5210 ± 487 cm3/m2, p = 0.02). In women, KES correlated more strongly with muscle parameters than HGS. Despite gender-specific variations, torso CT-derived parameters show promise for evaluating body composition and sarcopenia.
Asunto(s)
Composición Corporal , Impedancia Eléctrica , Fuerza Muscular , Tomografía Computarizada por Tomografía de Emisión de Positrones , Torso , Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Fuerza Muscular/fisiología , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Torso/diagnóstico por imagen , Torso/fisiología , Estudios Retrospectivos , Anciano , Sarcopenia/diagnóstico por imagen , Sarcopenia/fisiopatología , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/fisiologíaRESUMEN
INTRODUCTION: The apnea test (AT) is a crucial procedure in determining brain death (BD), with detection of spontaneous breathing efforts serving as a key criterion. Numerous national statutes mandate complete disconnection of the patient from the ventilator during the procedure to open the airway directly to the atmosphere. These regulations mandate visual observation as an exclusive option for detecting breathing efforts. However, reliance on visual observation alone can pose challenges in identifying subtle respiratory movements. CASE PRESENTATION: This case report presents a 55-year-old morbidly obese male patient with suspected BD due to cerebral hemorrhage undergoing an AT. The AT was performed with continuous electrical impedance tomography (EIT) monitoring. Upon detection of spontaneous breathing movements by both visual observation and EIT, the AT was aborted, and the patient was reconnected to the ventilator. EIT indicated a shift in ventilation distribution from the ventral to the dorsal regions, indicating the presence of spontaneous breathing efforts. EIT results also suggested the patient experienced a slow but transient initial recovery phase, likely due to atelectasis induced by morbid obesity, before returning to a steady state of ventilatory support. CONCLUSION: The findings suggest EIT could enhance the sensitivity and accuracy of detecting spontaneous breathing efforts, providing additional insights into the respiratory status of patients during the AT.
Asunto(s)
Apnea , Muerte Encefálica , Impedancia Eléctrica , Obesidad Mórbida , Tomografía , Humanos , Masculino , Muerte Encefálica/diagnóstico , Muerte Encefálica/fisiopatología , Persona de Mediana Edad , Apnea/diagnóstico , Apnea/fisiopatología , Tomografía/métodos , Obesidad Mórbida/complicaciones , Obesidad Mórbida/fisiopatología , Respiración , Hemorragia Cerebral/diagnóstico por imagen , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/fisiopatologíaRESUMEN
BACKGROUND: Body composition (BC) techniques, including bioelectrical impedance analysis (BIVA), nutritional ultrasound® (NU), and computed tomography (CT), can detect nutritional diagnoses such as sarcopenia (Sc). Sc in idiopathic pulmonary fibrosis (IPF) is associated with greater severity and lower survival. Our aim was to explore the correlation of BIVA, NU and functional parameters with BC at T12 level CT scans in patients with IPF but also its relationship with degree of Sc, malnutrition and mortality. METHODS: This bicentric cross-sectional study included 60 IPF patients (85.2% male, 70.9 ± 7.8 years). Morphofunctional assessment (MFA) techniques included BIVA, NU, CT at T12 level (T12-CT), handgrip strength, and timed up and go. CT data were obtained using FocusedON®. Statistical analysis was conducted using JAMOVI version 2.3.22 to determine the cutoff points for Sc in T12-CT and to analyze correlations with other MFA techniques. RESULTS: the cutoff for muscle area in T12-CT was ≤77.44 cm2 (area under the curve (AUC) = 0.734, sensitivity = 41.7%, specificity = 100%). The skeletal muscle index (SMI_T12CT) cutoff was ≤24.5 cm2/m2 (AUC = 0.689, sensitivity = 66.7%, specificity = 66.7%). Low SMI_T12CT exhibited significantly reduced median survival and higher risk of mortality compared to those with normal muscle mass (SMI cut off ≥ 28.8 cm/m2). SMI_T12CT was highly correlated with body cell mass from BIVA (r = 0.681) and rectus femoris cross-sectional area (RF-CSA) from NU (r = 0.599). Cronbach's α for muscle parameters across different MFA techniques and CT was 0.735, confirming their validity for evaluating muscle composition. CONCLUSIONS: T12-CT scan is a reliable technique for measuring low muscle mass in patients with IPF, specifically when the L3 vertebrae are not captured. An SMI value of <28.8 is a good predictor of low lean mass and 12-month mortality in IPF patients.
Asunto(s)
Composición Corporal , Impedancia Eléctrica , Fibrosis Pulmonar Idiopática , Sarcopenia , Tomografía Computarizada por Rayos X , Humanos , Sarcopenia/diagnóstico por imagen , Sarcopenia/diagnóstico , Masculino , Femenino , Fibrosis Pulmonar Idiopática/diagnóstico por imagen , Fibrosis Pulmonar Idiopática/mortalidad , Anciano , Estudios Transversales , Tomografía Computarizada por Rayos X/métodos , Persona de Mediana Edad , Fuerza de la Mano , Evaluación Nutricional , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/patología , Estado NutricionalRESUMEN
Dishcook is a new cooking system that allows individual cooking using a dedicated induction heater. This study investigated whether Dishcook use affects the nutritional value of individuals with intellectual disabilities. This study was conducted on users receiving support from a continuous-employment office in Obama City, Fukui Prefecture, in 2022. Of these participants, 18 (seven women and 11 men) who requested the use of the Dishcook were included in the analysis. The study period was from January to August 2023. The mean age was 48.72±16.24 y. A significant increase in the overall phase angles of the limbs was observed. Triglyceride, LDL cholesterol, HbA1c, and serum zinc levels improved in patients who used the Dishcook. The phase angle obtained using Bioelectrical Impedance Analysis also improved, indicating the usefulness of the Dishcook in treating metabolic diseases and the possibility of individualized nutritional management.
Asunto(s)
Culinaria , Discapacidad Intelectual , Estado Nutricional , Humanos , Femenino , Masculino , Adulto , Discapacidad Intelectual/dietoterapia , Persona de Mediana Edad , Culinaria/métodos , Triglicéridos/sangre , Hemoglobina Glucada/análisis , Zinc/sangre , Zinc/administración & dosificación , Impedancia Eléctrica , Biomarcadores/sangre , LDL-Colesterol/sangre , Anciano , JapónRESUMEN
OBJECTIVES: In an era when telemedicine is becoming increasingly essential, the development and validation of miniaturized Bioelectrical Impedance Analysis (BIA) devices for accurate and reliable body composition assessment is crucial. This study investigates the BIA Metadieta, a novel miniaturized BIA device, by comparing its performance with that of standard hospital BIA equipment across a diverse demographic. The aim is to enhance remote health monitoring by integrating compact and efficient technology into routine healthcare practices. METHODS: A cross-sectional observational study was conducted with 154 participants from the Clinical Nutrition Unit. The study compared resistance (R), reactance (Xc), and phase angle (PhA) measurements obtained from the BIA Metadieta device and a traditional hospital-based BIA device. RESULTS: Analysis revealed strong positive correlations between the BIA Metadieta and the hospital-based device for R (r = 0.988, P < 0.001), Xc (r = 0.946, P < 0.001), and PhA (r = 0.929, P < 0.001), indicating the miniaturized device's high accuracy and reliability. These correlations were consistent across different genders and BMI categories, demonstrating the device's versatility. CONCLUSIONS: The BIA Metadieta device, with its miniaturized form factor, represents a significant step forward in the field of remote health monitoring, providing a reliable, accurate, and accessible means for assessing body composition.
Asunto(s)
Composición Corporal , Impedancia Eléctrica , Humanos , Masculino , Estudios Transversales , Femenino , Persona de Mediana Edad , Adulto , Reproducibilidad de los Resultados , Anciano , Telemedicina/instrumentación , Adulto JovenRESUMEN
BACKGROUND: Factors associated with early-stage frailty (pre-frailty) in patients with chronic obstructive pulmonary disease (COPD) remain unestablished. In addition to skeletal muscle quantity, skeletal muscle dysfunction can be estimated using an angular metric from bioelectrical impedance analyzer (BIA), termed the phase angle, that reflects cell membrane reactance representing the structural stability. This study examined whether the phase angle was more closely associated with pre-frailty compared with skeletal muscle quantity in patients with COPD. METHODS: This cross-sectional analysis included stable smokers with and without COPD whose frailty status was assessed using the Japanese version of the Cardiovascular Health Study criteria. The phase angle and skeletal muscle index (SMI) were measured using BIA, and physical activity over one week was assessed using triaxial accelerometers. RESULTS: A total of 159 patients were categorized into robust, pre-frail, and frail groups (n = 38, 92, and 29, respectively). The phase angle was significantly smaller in the pre-frail and frail groups than in the robust group after adjusting for age, sex, height, body mass index, smoking history, and lung function. In contrast, SMI did not differ between the robust and pre-frail groups. When combining the pre-frail and frail groups into a non-robust group, 4.8° was determined as the cutoff phase angle value to identify non-robust status. A phase angle <4.8° was associated with shorter durations of moderate-intensity physical activity but not with light physical activity. CONCLUSIONS: A smaller phase angle was associated with pre-frailty and impaired moderate-intensity physical activity in smokers with and without COPD.
Asunto(s)
Impedancia Eléctrica , Fragilidad , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Masculino , Femenino , Anciano , Estudios Transversales , Fragilidad/fisiopatología , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Conducta Sedentaria , Acelerometría , Anciano de 80 o más Años , Ejercicio Físico/fisiología , Fumar/fisiopatologíaRESUMEN
OBJECTIVE: The study aimed to evaluate the improvements in pulmonary ventilation following a sitting position in ventilated ARDS patients using electrical impedance tomography. METHODOLOGY: A total of 17 patients with ARDS under mechanical ventilation participated in this study, including 8 with moderate ARDS and 9 with severe ARDS. Each patient was initially placed in the supine position (S1), transitioned to sitting position (SP) for 30 min, and then returned to the supine position (S2). Patients were monitored for each period, with parameters recorded. MAIN OUTCOME MEASURES: The primary outcome included the spatial distribution parameters of EIT, regional of interest (ROI), end-expiratory lung impedance (ΔEELI), and parameters of respiratory mechanics. RESULTS: Compared to S1, the SP significantly altered the distribution in ROI1 (11.29 ± 4.70 vs 14.88 ± 5.00 %, p = 0.003) and ROI2 (35.59 ± 8.99 vs 44.65 ± 6.97 %, p ï¼ 0.001), showing reductions, while ROI3 (39.71 ± 11.49 vs 33.06 ± 6.34 %, p = 0.009), ROI4 (13.35 ± 8.76 vs 7.24 ± 5.23 %, p ï¼ 0.001), along with peak inspiratory pressure (29.24 ± 3.96 vs 27.71 ± 4.00 cmH2O, p = 0.036), showed increases. ΔEELI decreased significantly ventrally (168.3 (40.33 - 189.5), p ï¼ 0.0001) and increased significantly dorsally (461.7 (297.5 - 683.7), p ï¼ 0.0001). The PaO2/FiO2 ratio saw significant improvement in S2 compared to S1 after 30 min in the seated position (108 (73 - 130) vs 96 (57 - 129) mmHg, p = 0.03). CONCLUSIONS: The sitting position is associated with enhanced compliance, improved oxygenation, and more homogenous ventilation in patients with ventilated ARDS compared to the supine position. IMPLICATIONS FOR CLINICAL PRACTICE: It is important to know the impact of postural changes on patient pulmonary ventilation in order to standardize safe practices in critically ill patients. It may be helpful in the management among ventilated patients.