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1.
Medicine (Baltimore) ; 98(50): e18100, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31852069

RESUMEN

INTRODUCTION: Pulse wave analysis is an emerging approach that analyzes parameters comprising strong predictors of cardiovascular (CV) events and all-cause mortality, especially in patients with high CV risk based on established risk factors. This study used the oscillometric method, provided by the Mobil-o-Graph (PWA-EMI GmbH, Stolberg, Germany) device, to compare data regarding the pulse wave analysis parameters in hypertensive nondiabetic and diabetic patients. MATERIAL AND METHODS: In this cross-sectional study, 276 individuals were examined in the academic hypertension outpatient care unit of the Federal University of the Triângulo, in Mineiro, Brazil, from January to December 2016. The pulse wave analysis was performed by oscillometry, and its parameters were acquired from all patients. RESULTS: Of the 276 patients, 99 were diabetic and 177 nondiabetic. The mean systolic and pulse central blood pressure were significantly higher in diabetic patients than in nondiabetic patients (P = .008 and.0003, respectively). The mean peripheral systolic blood pressure and pulse pressure were also significantly higher in the diabetic group (P = .001 and P < .0001, respectively). The average pulse wave velocity (PWV, m/s) was 9.4 ±â€Š1.6 and 8.8 ±â€Š1.6 in the diabetic and nondiabetic groups, respectively (P = .003). CONCLUSION: The group of hypertensive diabetic patients had significantly higher central blood pressure, peripheral blood pressure, and PWV than the hypertensive nondiabetic patients. The patients with overlapping established CV risk factors presented values of the pulse wave analysis parameters consistent with higher central pressure and greater arterial stiffness.


Asunto(s)
Atención Ambulatoria , Presión Sanguínea/fisiología , Diabetes Mellitus/fisiopatología , Hipertensión/fisiopatología , Oscilometría/métodos , Análisis de la Onda del Pulso/métodos , Rigidez Vascular/fisiología , Brasil/epidemiología , Estudios Transversales , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Hipertensión/diagnóstico , Hipertensión/epidemiología , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Factores de Riesgo , Sístole
2.
Blood Press Monit ; 24(5): 213-220, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31490245

RESUMEN

BACKGROUND: Before arterial cannulation for invasive blood pressure monitoring, clinical decision-making depends on non-invasive blood pressure in critically ill patients. Whether non-invasive blood pressure is comparable to invasive measurement is not clearly elucidated. We address this issue as it relates to the use of norepinephrine in patients with cardiogenic shock. METHODS: We analysed invasive and non-invasive blood pressure in 85 patients admitted to the Coronary-Care Unit for cardiogenic shock. We compared initial blood pressure measurement (just after radial artery cannulation) and blood pressure taken during the first 72 hours after admission. Invasive blood pressure was used as the reference method. RESULTS: Initial invasive mean and systolic arterial pressures were in a good agreement with oscillometric blood pressure; mean differences were -0.4 ± 8.8 and +6.1 ± 14.4 mmHg with correlation coefficients of 0.76 and 0.74. Doses of norepinephrine were significant negative determinants of invasive/oscillometric blood pressure differences. The invasive/oscillometric mean arterial pressures and SBP differences were +0.1 ± 3.4 and 7.6 ± 1.6 mmHg in patients treated with nothing or a maximum norepinephrine dose of 0.6 µg/kg/min. However, treatment with very high doses of norepinephrine was associated with a steep rise in mean arterial pressures and SBP invasive/oscillometric differences (-9.5 ± 3.3 and -8.5 ± 5.2 mmHg). In a total of 967 sets of blood pressure measurements, invasive/oscillometric differences were relatively stable across blood pressure categories, with the exception of measurements assessed after very high norepinephrine doses. CONCLUSIONS: Non-invasive BP is a sufficient substitute for invasive measurement in cardiogenic shock patients, with the exception of those receiving very high doses of norepinephrine.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Presión Sanguínea/efectos de los fármacos , Norepinefrina/farmacología , Choque Cardiogénico/fisiopatología , Vasoconstrictores/farmacología , Anciano , Anciano de 80 o más Años , Presión Arterial , Cateterismo , Enfermedad Crítica , Femenino , Humanos , Masculino , Persona de Mediana Edad , Monitoreo Fisiológico , Norepinefrina/administración & dosificación , Oscilometría/métodos , Estudios Prospectivos , Vasoconstrictores/administración & dosificación
3.
Wilderness Environ Med ; 30(3): 227-235, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31221602

RESUMEN

INTRODUCTION: In recent years a number of publications have appeared describing noninvasive blood pressure (NIBP) measurement with 1 layer of light cloth between the patient's skin and the NIBP cuff. In this study we investigated the reliability of NIBP measurements performed through 2 and 3 layers of autumn/winter clothing in 2 research groups: healthy volunteers and patients. METHODS: Oscillometric NIBP measurements were made in a random order: 1) on the exposed arm; 2) on the arm covered by a standardized cotton and polar fabric test sleeve; and 3) with the arm covered by a cotton-polar fabric and down jacket test sleeve. The time taken for measurement was also recorded. RESULTS: We performed measurement in 101 volunteers and 50 patients and found no clinically or statistically significant differences in NIBP. Mean±SD values in the volunteer group were 1) 130/80±14/8 mm Hg; 2) 130/81±15/8 mm Hg; and 3) 128/81±14/8 mm Hg. In the patient group the values were 1) 140/82±34/15 mm Hg; 2) 140/84±33/15 mm Hg; and 3) 137/84±32/15 mm Hg. Measuring over a sleeved arm extended the time of measurement by an average of 3.5 s in comparison with bare arm measurement. CONCLUSIONS: Our findings confirm that it is possible to perform reliable NIBP measurements over 2 and 3 layers of autumn/winter clothing. Measuring NIBP with a clothed arm does not show clinical or statistically significant differences in comparison with measurements performed on the bare arm.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Vestuario , Oscilometría/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Polonia , Estudios Prospectivos , Reproducibilidad de los Resultados , Estaciones del Año , Medicina Silvestre , Adulto Joven
4.
Eur J Anaesthesiol ; 36(6): 400-405, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31045698

RESUMEN

BACKGROUND: General anaesthesia in children results in a significant decrease of arterial pressure. Hypotension in neonates and infants reduces cerebral perfusion; therefore, an accurate arterial pressure measurement is of utmost importance. Although arterial pressure measured via an arterial catheter is considered to be the gold standard, in most children undergoing anaesthesia, arterial pressure is monitored by an upper arm cuff using an oscillometric technique. Data on the accuracy of these devices in such young patients are rare. OBJECTIVE: The aim of this study was to assess the accuracy of oscillometric blood pressure measurement compared with intra-arterial measurement. DESIGN: An observational comparison study. SETTING: A single-centre study, conducted in a German university hospital from November 2015 to January 2018. PATIENTS: Twenty-five children of 2 years old or less (median age 6 [IQR, 5 to 11]) months undergoing neurosurgical procedures requiring invasive arterial pressure determination. MAIN OUTCOME MEASURES: Arterial pressure was measured invasively and also oscillometrically by an upper arm cuff every 10 min. Simultaneously measured pairs of mean arterial pressures were analysed by the Bland-Altman method; the correlation coefficient, percentage error and concordance were calculated. RESULTS: Data from 21 children were analysed. Mean, (standard deviation) and [range] of invasive and noninvasive mean arterial pressures were 54 (8) [30 to 94] and 57 (8) [40 to 108] mmHg, respectively. The overall bias between invasive and noninvasive arterial pressure was -3 (7) mmHg, with 95% limits of agreement from -17 to +10 mmHg. The correlation coefficient, percentage error and concordance were 0.65, 25% and 0.77, respectively. For hypotensive invasive arterial pressure values below 45 mmHg, the mean bias (invasive arterial pressure - noninvasive arterial pressure) was -9 (5) mmHg. CONCLUSION: Arterial pressure derived by the oscillometric device showed acceptable levels of agreement. However, during hypotension, a clinically relevant overestimation of arterial pressure occurred when measured by an upper arm cuff.


Asunto(s)
Presión Arterial , Hipotensión/diagnóstico , Complicaciones Intraoperatorias/diagnóstico , Monitoreo Intraoperatorio/métodos , Procedimientos Neuroquirúrgicos/efectos adversos , Brazo , Determinación de la Presión Sanguínea/instrumentación , Determinación de la Presión Sanguínea/métodos , Cateterismo Periférico , Femenino , Humanos , Hipotensión/etiología , Lactante , Complicaciones Intraoperatorias/etiología , Masculino , Monitoreo Intraoperatorio/instrumentación , Oscilometría/instrumentación , Oscilometría/métodos , Estudios Prospectivos , Arteria Radial
5.
Immunol Allergy Clin North Am ; 39(2): 205-219, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30954171

RESUMEN

Objective measures of lung function are important in the diagnosis and management of asthma. Spirometry, the pulmonary function test most widely used in asthma, requires respiratory maneuvers that may be difficult for preschoolers. Impulse oscillometry (IOS) is a noninvasive method of measuring lung function during tidal breathing; hence, IOS is an ideal test for use in preschool asthma. Fractional exhaled nitric oxide (FeNO) levels correspond to eosinophilic inflammation and predict responsiveness to corticosteroids. Basic concepts of IOS, methodology, and interpretation, including available normative values, and recent findings regarding FeNO are reviewed in this article.


Asunto(s)
Asma/diagnóstico , Pruebas Respiratorias/métodos , Eosinófilos/inmunología , Inflamación/inmunología , Oscilometría/métodos , Corticoesteroides/uso terapéutico , Antiasmáticos/uso terapéutico , Biomarcadores Farmacológicos , Preescolar , Espiración , Humanos , Óxido Nítrico/metabolismo
6.
J Vet Med Sci ; 81(4): 513-516, 2019 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-30745524

RESUMEN

We investigated the clinical characteristics of healthy cats in accordance with the target organ damage (TOD) risk category, on the basis of systolic blood pressure (SBP). This prospective multi-center study included 137 healthy cats. Indirect blood pressure was measured using an oscillometric technique. The median SBP in all cats was 147 mmHg (interquartile range: 134-158). On the basis of the TOD risk category, 57.7, 19.7, 21.9, and 0.7% of the cats were classified into categories I-IV, respectively. Age, sex, and body weight did not affect the SBP. This study provides basic information on the distribution of TOD risk categories in clinically healthy cats.


Asunto(s)
Determinación de la Presión Sanguínea/veterinaria , Presión Sanguínea/fisiología , Gatos/fisiología , Oscilometría/veterinaria , Factores de Edad , Animales , Determinación de la Presión Sanguínea/métodos , Peso Corporal , Ecocardiografía/veterinaria , Estudios Epidemiológicos , Femenino , Hipertensión/complicaciones , Hipertensión/diagnóstico por imagen , Hipertensión/veterinaria , Masculino , Oscilometría/métodos , Estudios Prospectivos
7.
PLoS One ; 14(2): e0209618, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30726236

RESUMEN

Synchronizing chaotic oscillators has been a challenge to guarantee successful applications in secure communications. That way, three synchronization techniques are applied herein to twenty two chaotic oscillators, three of them based on piecewise-linear functions and nineteen proposed by Julien C. Sprott. These chaotic oscillators are simulated to generate chaotic time series that are used to evaluate their Lyapunov exponents and Kaplan-Yorke dimension to rank their unpredictability. The oscillators with the high positive Lyapunov exponent are implemented into a field-programmable gate array (FPGA), and afterwards they are synchronized in a master-slave topology applying three techniques: the seminal work introduced by Pecora-Carroll, Hamiltonian forms and observer approach, and open-plus-closed-loop (OPCL). These techniques are compared with respect to their synchronization error and latency that is associated to the FPGA implementation. Finally, the chaotic oscillators providing the high positive Lyapunov exponent are synchronized and applied to a communication system with chaotic masking to perform a secure image transmission. Correlation analysis is performed among the original image, the chaotic channel and the recovered image for the three synchronization schemes. The experimental results show that both Hamiltonian forms and OPCL can recover the original image and its correlation with the chaotic channel is as low as 0.00002, demonstrating the advantage of synchronizing chaotic oscillators with high positive Lyapunov exponent to guarantee high security in data transmission.


Asunto(s)
Oscilometría/métodos , Comunicación , Simulación por Computador , Modelos Teóricos , Factores de Tiempo
8.
Respir Res ; 20(1): 41, 2019 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-30808365

RESUMEN

BACKGROUND: Cough variant asthma (CVA) is one of the most common causes of chronic persistent cough, and early treatment with inhaled corticosteroids (ICSs) is recommended to attenuate the inflammation and remodeling. The impulse oscillometry system (IOS) is a novel device for respiratory functional assessment that has not yet been assessed in terms of CVA. Therefore, we investigated the relationship between CVA and IOS, and the difference in therapeutic effects of ICSs among the subtype classifications by IOS. METHODS: The following ICSs were randomly prescribed in daily medical care: coarse-particle ICS (fluticasone propionate [FP]), fine-particle ICS (mometasone furoate [MF]), and moderate-particle ICS (budesonide [BUD]). Treatment effects were assessed by the Leicester cough questionnaire (LCQ) and were compared among three separated subtypes based on IOS measurements: central, peripheral, and resistless. RESULTS: Regarding LCQ scores, in the central type, the LCQ of the MF group was significantly lower than FP and BUD. In the peripheral type, the LCQ of the FP group was significantly lower than MF and BUD. In the resistless type, the LCQ of the MF group was significantly lower than BUD. Also, IOS factors were improved by 4 weeks of therapy with ICS. Thus, there was strong relationship between subtypes and particle size in terms of effectiveness. CONCLUSIONS: There is a strong relationship between IOS subtype classification and ICS particle size in terms of therapeutic efficiency in CVA. It appears important to determine the ICS particle size, based on the IOS subtype classification, before treatment.


Asunto(s)
Corticoesteroides/administración & dosificación , Antiasmáticos/administración & dosificación , Asma/diagnóstico , Asma/tratamiento farmacológico , Tos/diagnóstico , Tos/tratamiento farmacológico , Oscilometría/métodos , Administración por Inhalación , Adulto , Asma/fisiopatología , Tos/fisiopatología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Distribución Aleatoria , Pruebas de Función Respiratoria/métodos , Estudios Retrospectivos , Resultado del Tratamiento
9.
J Med Syst ; 43(2): 24, 2019 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-30603777

RESUMEN

Blood pressure (BP) is a bio-physiological signal that can provide very useful information regarding human's general health. High or low blood pressure or its rapid fluctuations can be associated to various diseases or conditions. Nowadays, high blood pressure is considered to be an important health risk factor and major cause of various health problems worldwide. High blood pressure may precede serious heart diseases, stroke and kidney failure. Accurate blood pressure measurement and monitoring plays fundamental role in diagnosis, prevention and treatment of these diseases. Blood pressure is usually measured in the hospitals, as a part of a standard medical routine. However, there is an increasing demand for methodologies, systems as well as accurate and unobtrusive devices that will permit continuous blood pressure measurement and monitoring for a wide variety of patients, allowing them to perform their daily activities without any disturbance. Technological advancements in the last decade have created opportunities for using various devices as a part of ambient assisted living for improving quality of life for people in their natural environment. The main goal of this paper is to provide a comprehensive review of various methodologies for continuous cuff-less blood pressure measurement, as well as to evidence recently developed devices and systems for continuous blood pressure measurement that can be used in ambient assisted living applications.


Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial/instrumentación , Monitoreo Ambulatorio de la Presión Arterial/métodos , Electrocardiografía/métodos , Humanos , Oscilometría/métodos , Fotopletismografía/métodos , Esfigmomanometros , Dispositivos Electrónicos Vestibles
10.
Pediatr Allergy Immunol ; 30(1): 74-80, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30341960

RESUMEN

BACKGROUND: Both allergic and non-allergic rhinitis are associated with worse asthma control. However, it is unclear how IgE sensitization and/or rhinitis are associated with lung function. We therefore evaluated the effect of rhinitis and sensitization on lung function, including the periphery of the airway system, and inflammatory biomarkers in individuals with and without asthma. METHODS: Participants in the BAMSE longitudinal birth cohort study underwent measures of spirometry, impulse oscillometry, and FeNO at age 16 years. Questionnaires were used to obtain data on asthma and rhinitis. Blood samples were analyzed for eosinophils and allergen-specific IgE. RESULTS: Groups based on the combination of asthma, rhinitis, and sensitization were compared to a healthy reference group. Lower FEV1 /FVC levels were seen for groups with asthma only (adjusted mean difference -2.8% units (95% CI -4.7; -1.0), P < 0.01), asthma with sensitization (-2.0 (-3.9; -0.2), P < 0.05), and asthma with sensitization and rhinitis (-2.5 (-3.6; -1.4), P < 0.001). The index of peripheral airway resistance R5-20 was higher in groups with asthma and sensitization (adjusted median difference 94.9 Pa L-1  s-1 (95% CI 60.4; 129.3), P < 0.001), as well as asthma with sensitization and rhinitis (36.9(15.0; 58.8), P < 0.01). These groups also had increased FeNO and blood eosinophil levels. CONCLUSIONS: We found signs of peripheral airway obstruction and increased levels of inflammatory biomarkers in the presence of allergic asthma, irrespective of rhinitis status. Despite having a reduced FEV1 /FVC, peripheral airway engagement was not seen in non-sensitized adolescents with asthma. We suggest that small airway disease is a feature related to the eosinophilic inflammation in allergic asthma in adolescence.


Asunto(s)
Asma/fisiopatología , Biomarcadores/sangre , Inmunoglobulina E/sangre , Pulmón/fisiopatología , Rinitis/fisiopatología , Adolescente , Estudios de Cohortes , Eosinófilos/inmunología , Femenino , Humanos , Inmunización , Inmunoglobulina E/inmunología , Estudios Longitudinales , Masculino , Oscilometría/métodos , Espirometría/métodos , Suecia
11.
Allergol Immunopathol (Madr) ; 47(3): 295-302, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29983239

RESUMEN

PURPOSE: To review available evidence in the literature on impulse oscillometry in the assessment of lung function in children with respiratory diseases, especially asthma. DATA COLLECTION: Research in the Medline, PubMed, and Lilacs databases, with the keywords forced oscillation, impulse oscillometry, asthma and impulse oscillometry. RESULTS: The Impulse Oscillometry System (IOS) allows the measurement of resistance and reactance of airways and is used as a diagnostic resource. A significant association between the findings of the IOS and those of spirometry is observed. In asthma, the IOS has already been used to assess the bronchodilator response and the therapeutic response to different drugs and has shown to be a sensitive technique to evaluate disease control. There are limitations to this assessment, such as children with attention deficit and in some cases it is difficult to interpret the results from a clinical point of view. CONCLUSION: The IOS is a useful tool for the measurement of the lung function of children. It is an easy test, although its interpretation is not straightforward.


Asunto(s)
Asma/diagnóstico , Enfermedades Pulmonares/diagnóstico , Pulmón/fisiología , Oscilometría/métodos , Pruebas de Función Respiratoria/métodos , Animales , Humanos
12.
Biomed Tech (Berl) ; 64(3): 263-273, 2019 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-30052513

RESUMEN

Oscillometry is the most popular technique for automatic blood pressure (BP) estimation. This method relies on recording the cuff deflation curve (CDC) from a high suprasystolic BP (SSBP) to a low subdiastolic BP (SDBP) and is very sensitive to noise caused by breathing, motion artifacts, muscle contraction and the environment. We developed a unified BP estimation method involving two integrated sub-procedures based on the arterial lumen area (ALA) model and applied it for continuous BP measurement. Our proposed method is coefficient free and continuous. No empirical coefficients are applied, and the CDC varies within a low-pressure range of 40-80 mm Hg, which can be sustainably imposed on our wrists. The first sub-procedure estimates the mean arterial pressure (MAP) and arterial compliance parameter b under a complete CDC period. In the second sub-procedure, the systolic BP (SBP) and diastolic BP (DBP) are estimated based on the dynamic-updated oscillometric waveform. We applied this method on 300 continuously oscillometric traces recorded from 20 male and female healthy subjects aged 20-60 years. The validated results were compared with those from a double stethoscope check. We observed mean absolute errors of 4.77 and 4.24 mm Hg in estimating the SBP and DBP, respectively.


Asunto(s)
Presión Arterial/fisiología , Determinación de la Presión Sanguínea/métodos , Presión Sanguínea/fisiología , Oscilometría/métodos , Arterias , Artefactos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
13.
J. vasc. bras ; 18: e20180073, 2019. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1002487

RESUMEN

Background Elevated arterial stiffness is associated with increased cardiovascular mortality. The relationship between arterial stiffness and critical limb ischemia (CLI) is not well established. Objectives The objective of this study is to analyze the relationship between arterial stiffness indices and the degree of limb ischemia measured by the ankle-brachial index (ABI). Methods A cross-sectional study comparing patients with CLI and controls. Arterial stiffness was measured using brachial artery oscillometry. The arterial stiffness indices pulse wave velocity (PWV) and augmentation index normalized to 75 beats/min (AIx@75) were determined. Multiple linear regression was applied to identify predictors of arterial stiffness indices. Results Patients in the CLI group had higher PWV (12.1±1.9 m/s vs. 10.1±1.9 m/s, p < 0.01) and AIx@75 (31.8±7.8% vs. 17.5±10.8%, p < 0.01) than controls. Central systolic pressure was higher in the CLI group (129.2±18.4 mmHg vs. 115.2±13.1 mmHg, p < 0.01). There was an inverse relationship between AIx@75 and ABI (Pearson coefficient = 0.24, p = 0.048), but there was no relationship between ABI and PWV (Pearson coefficient = 0.19, p = 0.12). In multiple regression analysis, reduced ABI was a predictor of elevated levels of AIx@75 (β = -25.02, p < 0.01). Conclusions Patients with CLI have high arterial stiffness measured by brachial artery oscillometry. The degree of limb ischemia, as measured by the ABI, is a predictor of increased AIx@75. The increased AIx@75 observed in CLI may have implications for the prognosis of this group of patients with advanced atherosclerosis


A rigidez arterial aumentada está associada ao aumento da mortalidade cardiovascular. A relação entre rigidez arterial e isquemia crítica do membro (IC) não está bem estabelecida. Objetivos O objetivo deste estudo é analisar a relação entre índices de rigidez arterial e o grau de isquemia de membro medido pelo índice tornozelo-braço (ITB). Métodos Foi feito um estudo transversal em pacientes com IC e controles. A rigidez arterial foi medida usando a oscilometria da artéria braquial. Os índices de rigidez arterial mensurados foram a velocidade de onda de pulso (VOP) e o índice de aumentação corrigido para a frequência cardíaca de 75 batimentos/min (AIx@75). Regressão linear múltipla foi aplicada para identificar preditores dos índices de rigidez arterial. Resultados Pacientes do grupo IC tiveram VOP (12,1±1,9 m/s vs. 10,1±1,9 m/s, p < 0,01) e AIx@75 (31,8±7,8% vs. 17,5±10,8%, p < 0,01) maiores que controles. Pressão sistólica central foi maior no grupo IC (129,2±18,4 mmHg vs. 115,2±13,1 mmHg, p < 0,01). Houve uma relação inversa entre o AIx@75 e o ITB (coeficiente de Pearson = 0,19, p = 0,12). A análise de regressão múltipla mostrou que o ITB reduzido foi um preditor de elevação do AIx@75 (β = -25,02, p < 0,01). Conclusões Pacientes com IC têm elevada rigidez arterial medida por oscilometria da artéria braquial. O grau de isquemia do membro, medido pelo ITB, é um preditor do AIx@75 elevado. O aumento do AIx@75 na IC pode ter implicações de prognóstico no grupo de pacientes com aterosclerose avançada


Asunto(s)
Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Anciano de 80 o más Años , Arteria Braquial , Índice Tobillo Braquial , Rigidez Vascular , Isquemia/diagnóstico , Oscilometría/métodos , Presión Sanguínea , Enfermedades Cardiovasculares/mortalidad , Grupos Control , Estudios Transversales , Análisis Estadístico , Extremidad Inferior , Diabetes Mellitus , Aterosclerosis/complicaciones , Enfermedad Arterial Periférica , Hipertensión
14.
Respir Med ; 145: 8-13, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30509720

RESUMEN

OBJECTIVE: This study investigated the accuracy of impulse oscillometry (IOS) combined with fractional exhaled nitric oxide (FeNO) to assess asthma control among preschool children. METHODS: A total of 79 preschool children(3-6 year old) with asthma and 25 healthy preschool children who visited a paediatrician were enrolled in this study. All of the children were tested for allergens, respiratory system resistance (at 5 and 20 Hz [R5, R20]), respiratory system reactance (at 5 Hz [X5]), the resonant frequency of reactance (Fres), and the area under the reactance curve (between 5 Hz and Fres (reactance area [AX]) using IOS and FeNO. A paediatric respiratory specialist who was unaware of the IOS and FeNO results assigned children with asthma to either the asthma-controlled group (n = 27) or the asthma-uncontrolled group (n = 52) based on the Global Initiative for Asthma (GINA) criteria. A healthy control group (n = 25) was also included. The relationships between the FeNO and IOS values as well as the asthma control of the three groups were analysed, and the areas under the curve (AUCs) were calculated for each measure. RESULTS: (1) During the controlled group, means±standard deviations of AX, R5-20, R5, X5 and FeNO were 26.15 ±â€¯7.534, 3.52 ±â€¯1.311,9.97 ±â€¯1.576,-3.85 ±â€¯0.572,-3.85 ±â€¯0.572. During the uncontrolled group, means±standard deviations of AX,R5-20,R5,X5 and FeNO were 38.34 ±â€¯13.563,5.36 ±â€¯1.545,11.41 ±â€¯2.029,-5.07 ±â€¯1.554,36.40 ±â€¯21.07. Among preschool children, significant differences were observed between the controlled and uncontrolled group with regard to the small airway functional parameters (AX, R5-20, R5, and X5) and FeNO(P <0.05).(2) A receiver operating characteristic (ROC) analysis showed that the AUCs were 0.786 for FeNO alone, 0.751 for X5 alone, and 0.866 for X5 combined with FeNO (cut-off value: 27 ppb). CONCLUSION: FeNO combined with the small airway function parameter X5 accurately assessed asthma control among preschool children.


Asunto(s)
Asma/diagnóstico , Asma/terapia , Pruebas Respiratorias/métodos , Óxido Nítrico/análisis , Oscilometría/métodos , Sistema Respiratorio/fisiopatología , Asma/fisiopatología , Niño , Preescolar , Femenino , Humanos , Masculino , Curva ROC
15.
J Clin Hypertens (Greenwich) ; 20(12): 1683-1685, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30402943

RESUMEN

The measurement of blood pressure in the office (OBP) remains the basis for hypertension diagnosis and management for more than half a century. Despite the increasing use of out-of-office blood pressure measurement using home and less so ambulatory monitoring and their endorsement by hypertension societies, at present and for some time to come it is likely that in many people the diagnosis and management of hypertension will be based on OBP measurement alone. OBP measurement is a very variable method affected by multiple factors, which have major impact on the OBP level, reproducibility and prognostic ability. Thus, there are several types of OBP measurement, depending on the device type, conditions, observer's presence and the number of readings. The 4 main OBP types are: Type I: Auscultatory OBP in clinical practice; Type II: Automated attended OBP in clinical practice; Type III: Research setting OBP; Type IV: Unattended automated OBP. These OBP types have different standardization level, different reproducibility, different clinical relevance and different thresholds for hypertension diagnosis. Unless the methodological details of OBP measurement are reported, any conclusions based on such measurements in clinical research and in practice are questionable.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Presión Sanguínea/fisiología , Hipertensión/diagnóstico , Visita a Consultorio Médico/estadística & datos numéricos , Auscultación/instrumentación , Auscultación/métodos , Automatización/instrumentación , Automatización/métodos , Determinación de la Presión Sanguínea/instrumentación , Monitoreo Ambulatorio de la Presión Arterial/métodos , Humanos , Hipertensión/fisiopatología , Oscilometría/instrumentación , Oscilometría/métodos , Pautas de la Práctica en Medicina/tendencias , Ensayos Clínicos Controlados Aleatorios como Asunto , Reproducibilidad de los Resultados
16.
J Acoust Soc Am ; 144(3): 1160, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30424663

RESUMEN

Pulsed high intensity focused ultrasound was shown to enhance chemotherapeutic drug uptake in tumor tissue through inertial cavitation, which is commonly assumed to require peak rarefactional pressures to exceed a certain threshold. However, recent studies have indicated that inertial cavitation activity also correlates with the presence of shocks at the focus. The shock front amplitude and corresponding peak negative pressure (p -) in the focal waveform are primarily determined by the transducer F-number: less focused transducers produce shocks at lower p -. Here, the dependence of inertial cavitation activity on the transducer F-number was investigated in agarose gel by monitoring broadband noise emissions with a coaxial passive cavitation detector (PCD) during pulsed exposures (pulse duration 1 ms, pulse repetition frequency 1 Hz) with p- varying within 1-15 MPa. Three 1.5 MHz transducers with the same aperture, but different focal distances (F-numbers 0.77, 1.02, 1.52) were used. PCD signals were processed to extract cavitation probability, persistence, and mean noise level. At the same p -, all metrics indicated enhanced cavitation activity at higher F-numbers; specifically, cavitation probability reached 100% when shocks formed at the focus. These results provide further evidence supporting the excitation of inertial cavitation at reduced p - by waveforms with nonlinear distortion and shocks.


Asunto(s)
Modelos Biológicos , Oscilometría/métodos , Transductores , Ondas Ultrasónicas , Oscilometría/instrumentación
17.
PLoS One ; 13(11): e0206329, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30383781

RESUMEN

BACKGROUND: This study examined the short-term reproducibility of non-invasive estimates of central and peripheral blood pressure and markers of central systolic loading (augmentation index [AIx; a measure of central systolic loading] and AIx75 [AIx standardised to 75 b·min-1 heart rate]) and the effect of posture and fasting state on these variables in patients with acute stroke. METHODS: Twenty-two acute stroke patients (72 ± 10y) had blood pressure measured using the SphygmoCor XCEL in supine and seated postures and whilst fasted and non-fasted. RESULTS: Acceptable short-term reproducibility (ICC >0.75) was reported for all peripheral and central variables in all conditions (ICC = 0.77-0.90) and for AIx and AIx75 in both fasted postures (ICC = 0.78-0.81). Food consumption significantly lowered all blood pressures (p <0.05; η2p = 0.20-0.55). The seated posture resulted in a significantly greater AIx than supine (p <0.05; η2p = 0.22). Fasting state had significant main effects on AIx and AIx75 (p <0.05; η2p = 0.14-0.22). CONSLUSIONS: Oscillometric estimates of central blood pressure have high short-term reproducibility in different postures and fasting states but markers of systolic load should be assessed whilst fasted. Fasting state has a large effect on central and peripheral blood pressures and on measures of systolic loading. It is important for clinicians to be aware of optimal assessment conditions without this impacting on patient wellbeing. TRIAL REGISTRATION: Clinical trial registry name: NCT02537652.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Presión Sanguínea/fisiología , Ayuno/fisiología , Oscilometría/métodos , Postura/fisiología , Accidente Cerebrovascular/fisiopatología , Enfermedad Aguda , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de la Onda del Pulso , Reproducibilidad de los Resultados , Accidente Cerebrovascular/diagnóstico , Sístole , Reino Unido
18.
J Clin Hypertens (Greenwich) ; 20(12): 1703-1711, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30450732

RESUMEN

Reservoir pressure parameters [eg, reservoir pressure (RP) and excess pressure (XSP)] are biomarkers derived from blood pressure (BP) waveforms that have been shown to predict cardiovascular events independent of conventional cardiovascular risk markers. However, whether RP and XSP can be derived non-invasively from operator-independent cuff device measured brachial or central BP waveforms has never been examined. This study sought to achieve this by comparison of cuff reservoir pressure parameters with intra-aortic reservoir pressure parameters. 162 participants (aged 61 ± 10 years, 72% male) undergoing coronary angiography had the simultaneous measurement of cuff BP waveforms (via SphygmoCor XCEL, AtCor Medical) and intra-aortic BP waveforms (via fluid-filled catheter). RP and XSP derived from cuff acquired brachial and central BP waveforms were compared with intra-aortic measures. Concordance between brachial-cuff and intra-aortic measurement was moderate-to-good for RP peak (36 ± 11 vs 48 ± 14 mm Hg, P < 0.001; ICC 0.77, 95% CI: 0.71-0.82), and poor-to-moderate for XSP peak (28 ± 10 vs 24 ± 9 mm Hg, P < 0.001; ICC 0.49, 95% CI: 0.35-0.60). Concordance between central-cuff and intra-aortic measurement was moderate-to-good for RP peak (35 ± 9 vs 46 ± 14 mm Hg, P < 0.001; ICC 0.77, 95% CI: 0.70-0.82), but poor for XSP peak (12 ± 3 vs 24 ± 9 mm Hg, P < 0.001; ICC 0.12, 95% CI: -0.13 to 0.31). In conclusion, both brachial-cuff and central-cuff methods can reasonably estimate intra-aortic RP, whereas XSP can only be acceptably derived from brachial-cuff BP waveforms. This should enable widespread application to determine the clinical significance, but there is significant room for refinement of the method.


Asunto(s)
Presión Arterial/fisiología , Presión Sanguínea/fisiología , Arteria Braquial/fisiología , Enfermedades Cardiovasculares/fisiopatología , Anciano , Australia/epidemiología , Determinación de la Presión Sanguínea/instrumentación , Determinación de la Presión Sanguínea/métodos , Enfermedades Cardiovasculares/diagnóstico , Catéteres , Angiografía Coronaria/métodos , Femenino , Hemodinámica/fisiología , Humanos , Masculino , Persona de Mediana Edad , Oscilometría/instrumentación , Oscilometría/métodos
19.
Can J Vet Res ; 82(4): 244-248, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30363283

RESUMEN

The objective of this study was to characterize arterial blood pressure (BP) measurements obtained by using 2 indirect methods, oscillometry and Doppler ultrasonic sphygmomanometry, in conscious goats. Agreement between systolic BP yielded by these 2 methods was then assessed. Sixty female dairy goats aged from 1.5 to 11.8 y (median: 5.5 y) were examined in a standing position with a cuff placed on the tail. All goats had a severe arthritic form of caprine arthritis-encephalitis. Three to 5 repeated measurements of each BP type were averaged for each goat and considered as a final measurement. With oscillometry, systolic blood pressure (O-SBP), diastolic blood pressure, and mean blood pressure, as well as heart rate (HR) were measured, while only systolic blood pressure was measured with Doppler (D-SBP). The O-SBP did not correlate with D-SBP [correlation coefficient (r) = 0.24, P = 0.067]; the mean difference (± standard deviation) was 24.5 ± 26.3 mmHg and limits of agreement were from -27.2 mmHg [95% confidence interval (CI): -39.0, -15.4 mmHg] to 76.1 mmHg (95% CI: 64.3, 87.9 mmHg). No significant linear correlation was found between any BPs and HR (r: -0.10 to 0.22) or age (r: -0.26 to 0.07) of the goats. The study showed that, while BP could be measured in conscious goats using both oscillometry and Doppler ultrasonic sphygmomanometry, the results obtained were so inconsistent that these methods could not be used interchangeably.


Asunto(s)
Determinación de la Presión Sanguínea/veterinaria , Presión Sanguínea/fisiología , Cabras/fisiología , Oscilometría/veterinaria , Esfigmomanometros/veterinaria , Ultrasonografía Doppler/veterinaria , Animales , Determinación de la Presión Sanguínea/instrumentación , Determinación de la Presión Sanguínea/métodos , Femenino , Frecuencia Cardíaca , Oscilometría/instrumentación , Oscilometría/métodos , Ultrasonografía Doppler/instrumentación
20.
Int J Chron Obstruct Pulmon Dis ; 13: 3281-3295, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30349233

RESUMEN

Purpose: The aim of the present study was to evaluate the performance of the forced oscillation technique (FOT) for the early diagnosis of the effects of smoking and COPD. The contributions of the integer-order (InOr) and fractional-order (FrOr) models were also evaluated. Patients and methods: In total, 120 subjects were analyzed: 40 controls, 40 smokers (20.3±9.3 pack-years) and 40 patients with mild COPD. Results: Initially, it was observed that traditional FOT parameters and the InOr and FrOr models provided a consistent description of the COPD pathophysiology. Mild COPD introduced significant increases in the FrOr inertance, damping factor and hysteresivity (P<0.0001). These parameters were significantly correlated with the spirometric parameters of central and small airway obstruction (P<0.0001). The diagnostic accuracy analyses indicated that FOT parameters and InOr modeling may adequately identify these changes (area under the receiver operating characteristic curve - AUC >0.8). The use of FrOr modeling significantly improved this process (P<0.05), allowing the early diagnosis of smokers and patients with mild COPD with high accuracy (AUC >0.9). Conclusion: FrOr modeling improves our knowledge of modifications that occur in the early stages of COPD. Additionally, the findings of the present study provide evidence that these models may play an important role in the early diagnosis of COPD, which is crucial for improving the clinical management of the disease.


Asunto(s)
Resistencia de las Vías Respiratorias/fisiología , Diagnóstico Precoz , Oscilometría/métodos , Enfermedad Pulmonar Obstructiva Crónica , Fumar , Obstrucción de las Vías Aéreas/fisiopatología , Brasil , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Gravedad del Paciente , Manejo de Atención al Paciente/métodos , Manejo de Atención al Paciente/normas , Modelación Específica para el Paciente , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Mejoramiento de la Calidad , Pruebas de Función Respiratoria/métodos , Fumar/fisiopatología , Capacidad Vital
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