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1.
Anesthesiology ; 134(2): 179-188, 2021 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-33326001

RESUMO

BACKGROUND: The optimal method for blood pressure monitoring in obese surgical patients remains unknown. Arterial catheters can cause potential complications, and noninvasive oscillometry provides only intermittent values. Finger cuff methods allow continuous noninvasive monitoring. The authors tested the hypothesis that the agreement between finger cuff and intraarterial measurements is better than the agreement between oscillometric and intraarterial measurements. METHODS: This prospective study compared intraarterial (reference method), finger cuff, and oscillometric (upper arm, forearm, and lower leg) blood pressure measurements in 90 obese patients having bariatric surgery using Bland-Altman analysis, four-quadrant plot and concordance analysis (to assess the ability of monitoring methods to follow blood pressure changes), and error grid analysis (to describe the clinical relevance of measurement differences). RESULTS: The difference (mean ± SD) between finger cuff and intraarterial measurements was -1 mmHg (± 11 mmHg) for mean arterial pressure, -7 mmHg (± 14 mmHg) for systolic blood pressure, and 0 mmHg (± 11 mmHg) for diastolic blood pressure. Concordance between changes in finger cuff and intraarterial measurements was 88% (mean arterial pressure), 85% (systolic blood pressure), and 81% (diastolic blood pressure). In error grid analysis comparing finger cuff and intraarterial measurements, the proportions of measurements in risk zones A to E were 77.1%, 21.6%, 0.9%, 0.4%, and 0.0% for mean arterial pressure, respectively, and 89.5%, 9.8%, 0.2%, 0.4%, and 0.2%, respectively, for systolic blood pressure. For mean arterial pressure and diastolic blood pressure, absolute agreement and trending agreement between finger cuff and intraarterial measurements were better than between oscillometric (at each of the three measurement sites) and intraarterial measurements. Forearm performed better than upper arm and lower leg monitoring with regard to absolute agreement and trending agreement with intraarterial monitoring. CONCLUSIONS: The agreement between finger cuff and intraarterial measurements was better than the agreement between oscillometric and intraarterial measurements for mean arterial pressure and diastolic blood pressure in obese patients during surgery. Forearm oscillometry exhibits better measurement performance than upper arm or lower leg oscillometry.


Assuntos
Cirurgia Bariátrica , Determinação da Pressão Arterial/métodos , Monitorização Intraoperatória/métodos , Obesidade/cirurgia , Pressão Sanguínea , Determinação da Pressão Arterial/estatística & dados numéricos , Cateterismo Periférico/métodos , Cateterismo Periférico/estatística & dados numéricos , Feminino , Dedos , Humanos , Masculino , Pessoa de Meia-Idade , Oscilometria/métodos , Oscilometria/estatística & dados numéricos , Estudos Prospectivos , Reprodutibilidade dos Testes
2.
Anesthesiology ; 133(5): 997-1006, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33048167

RESUMO

BACKGROUND: In most patients having noncardiac surgery, blood pressure is measured with the oscillometric upper arm cuff method. Although the method is noninvasive and practical, it is known to overestimate intraarterial pressure in hypotension and to underestimate it in hypertension. A high-fidelity upper arm cuff incorporating a hydraulic sensor pad was recently developed. The aim of the present study was to investigate whether noninvasive blood pressure measurements with the new high-fidelity cuff correspond to invasive measurements with a femoral artery catheter, especially at low blood pressure. METHODS: Simultaneous measurements of blood pressure recorded from a femoral arterial catheter and from the high-fidelity upper arm cuff were compared in 110 patients having major abdominal surgery or neurosurgery. RESULTS: 550 pairs of blood pressure measurements (5 pairs per patient) were considered for analysis. For mean arterial pressure measurements, the average bias was 0 mmHg, and the precision was 3 mmHg. The Pearson correlation coefficient was 0.96 (P < 0.0001; 95% CI, 0.96 to 0.97), and the percentage error was 9%. Error grid analysis showed that the proportions of mean arterial pressure measurements done with the high-fidelity cuff method were 98.4% in zone A (no risk), 1.6% in zone B (low risk) and 0% in zones C, D, and E (moderate, significant, and dangerous risk, respectively). The high-fidelity cuff method detected mean arterial pressure values less than 65 mmHg with a sensitivity of 84% (95% CI, 74 to 92%) and a specificity of 97% (95% CI, 95% to 98%). To detect changes in mean arterial pressure of more than 5 mmHg, the concordance rate between the two methods was 99.7%. Comparable accuracy and precision were observed for systolic and diastolic blood pressure measurements. CONCLUSIONS: The new high-fidelity upper arm cuff method met the current international standards in terms of accuracy and precision. It was also very accurate to track changes in blood pressure and reliably detect severe hypotension during noncardiac surgery.


Assuntos
Pressão Arterial/fisiologia , Determinação da Pressão Arterial/métodos , Determinação da Pressão Arterial/normas , Monitorização Intraoperatória/métodos , Monitorização Intraoperatória/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Determinação da Pressão Arterial/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Intraoperatória/instrumentação , Oscilometria/instrumentação , Oscilometria/métodos , Oscilometria/normas , Estudos Prospectivos , Adulto Jovem
3.
Phys Rev Lett ; 125(9): 094101, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32915595

RESUMO

Synchronization is a widespread phenomenon observed in physical, biological, and social networks, which persists even under the influence of strong noise. Previous research on oscillators subject to common noise has shown that noise can actually facilitate synchronization, as correlations in the dynamics can be inherited from the noise itself. However, in many spatially distributed networks, such as the mammalian circadian system, the noise that different oscillators experience can be effectively uncorrelated. Here, we show that uncorrelated noise can in fact enhance synchronization when the oscillators are coupled. Strikingly, our analysis also shows that uncorrelated noise can be more effective than common noise in enhancing synchronization. We first establish these results theoretically for phase and phase-amplitude oscillators subject to either or both additive and multiplicative noise. We then confirm the predictions through experiments on coupled electrochemical oscillators. Our findings suggest that uncorrelated noise can promote rather than inhibit coherence in natural systems and that the same effect can be harnessed in engineered systems.


Assuntos
Relógios Biológicos , Modelos Teóricos , Humanos , Oscilometria/métodos , Processos Estocásticos
4.
J Med Syst ; 44(5): 91, 2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32185510

RESUMO

Oscillometry blood pressure measurements are commonly used to measure blood pressure for many patients at hospitals, home, and office and they are actively studied recently. These devices generally offer a single blood pressure point and they are not able to indicate the confidence interval of the measured quantity. Therefore, we introduce a novel technique using ensemble-based adaptive methodology to measure confidence interval for oscillometry blood pressure measurements. The ensemble-based adaptive methodology that is used to accurately estimate blood pressure and then measure the confidence interval for the systolic blood pressure and diastolic blood pressure.


Assuntos
Algoritmos , Determinação da Pressão Arterial , Oscilometria , Pressão Sanguínea , Determinação da Pressão Arterial/métodos , Intervalos de Confiança , Humanos , Oscilometria/métodos
5.
Am J Respir Crit Care Med ; 201(12): 1536-1544, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32135068

RESUMO

Rationale: Acute cellular rejection (ACR) is common during the initial 3 months after lung transplant. Patients are monitored with spirometry and routine surveillance transbronchial biopsies. However, many centers monitor patients with spirometry only because of the risks and insensitivity of transbronchial biopsy for detecting ACR. Airway oscillometry is a lung function test that detects peripheral airway inhomogeneity with greater sensitivity than spirometry. Little is known about the role of oscillometry in patient monitoring after a transplant.Objectives: To characterize oscillometry measurements in biopsy-proven clinically significant (grade ≥2 ACR) in the first 3 months after a transplant.Methods: We enrolled 156 of the 209 double lung transplant recipients between December 2017 and March 2019. Weekly outpatient oscillometry and spirometry and surveillance biopsies at Weeks 6 and 12 were conducted at our center.Measurements and Main Results: Of the 138 patients followed for 3 or more months, 15 patients had 16 episodes of grade 2 ACR (AR2) and 44 patients had 64 episodes of grade 0 ACR (AR0) rejection associated with stable and/or improving spirometry. In 15/16 episodes of AR2, spirometry was stable or improving in the weeks leading to transbronchial biopsy. However, oscillometry was markedly abnormal and significantly different from AR0 (P < 0.05), particularly in integrated area of reactance and the resistance between 5 and 19 Hz, the indices of peripheral airway obstruction. By 2 weeks after biopsy, after treatment for AR2, oscillometry in the AR2 group improved and was similar to the AR0 group.Conclusions: Oscillometry identified physiological changes associated with AR2 that were not discernible by spirometry and is useful for graft monitoring after a lung transplant.


Assuntos
Resistência das Vias Respiratórias/fisiologia , Rejeição de Enxerto/diagnóstico , Transplante de Pulmão , Oscilometria/métodos , Testes de Função Respiratória/métodos , Doença Aguda , Biópsia , Broncoscopia , Elasticidade , Volume Expiratório Forçado , Glucocorticoides/uso terapêutico , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/patologia , Rejeição de Enxerto/fisiopatologia , Humanos , Imunidade Celular , Metilprednisolona/uso terapêutico , Espirometria
6.
Biomed Res Int ; 2020: 8571062, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32025521

RESUMO

Background: Asymptomatic atherosclerosis is a common entity even at young age. Studies have suggested a strong relationship between increased arterial stiffness and asymptomatic carotid atherosclerosis (ACA) in general population, particularly in those with high cardiovascular risk, but no data exist from a younger population free from recognized cardiovascular disease. Hypothesis. We hypothesized there is an association between ACA and aortic pulse wave velocity (PWVao) in middle-aged, apparently healthy, normotensive population to reveal increased cardiovascular risk. Methods: We examined the relationship between ACA and PWVao in 236 apparently healthy, asymptomatic, normotensive, middle-aged subjects (age 47 ± 8 years; 52% women). PWVao was measured with the oscillometric method (Arteriograph). ACA was assessed by carotid artery ultrasonography. Results: ACA was present in 51 subjects. Subjects with ACA were older (p < 0.009), more likely to be smokers (p < 0.009), more likely to be smokers (p < 0.009), more likely to be smokers (p < 0.009), more likely to be smokers (p < 0.009), more likely to be smokers (p < 0.009), more likely to be smokers (p < 0.009), more likely to be smokers (p < 0.009), more likely to be smokers (. Conclusions: PWVao measured by the Arteriograph proved to be an independent marker of ACA. Our study may reveal high CV risk, detected as increased PWVao, which according to our study is related in a very high probability to asymptomatic carotid atherosclerosis in apparently healthy, young, and middle-aged subjects.


Assuntos
Angiografia/métodos , Aorta , Doenças das Artérias Carótidas/diagnóstico , Oscilometria/métodos , Análise de Onda de Pulso/métodos , Adulto , Idoso , Aterosclerose/diagnóstico , Artérias Carótidas , Estudos Transversais , Feminino , Humanos , Hungria , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Ultrassonografia/métodos , Rigidez Vascular
8.
Arch. bronconeumol. (Ed. impr.) ; 56(1): 9-17, ene. 2020. graf, tab
Artigo em Espanhol | IBECS | ID: ibc-186460

RESUMO

Introducción: La disfunción de las pequeñas vías aéreas (DPV) inducida por el tabaco contribuye precozmente a la patogenia de la limitación al flujo aéreo (LFA), aunque resulta poco conocida su repercusión en la percepción de salud. Se pretende evaluar la frecuencia de DPV en fumadores activos sin LFA y comparar la calidad de vida relacionada con la salud (CVRS) de no fumadores, fumadores sin DPV, fumadores con DPV y fumadores con LFA. Métodos: En 53 fumadores activos sin LFA, 20 fumadores con LFA y 20 no fumadores, se utilizaron los cuestionarios SF-36 y EuroQoL y se realizó oscilometría de impulsos, espirometría y determinación de las densidades de atenuación del parénquima pulmonar en inspiración y espiración máximas. Se consideró que existía DPV cuando la resistencia a 5 Hz (R5), la diferencia R5-R20 y el área de reactancia (AX) excedían su límite superior de la normalidad. Resultados: El 35,8% de los fumadores sin LFA tenía DPV. No se detectaron diferencias en los parámetros espirométricos ni la atenuación pulmonar entre los fumadores con o sin DPV y los no fumadores. Sin embargo, los fumadores con DPV presentaban una peor puntuación en los cuestionarios de CVRS que los fumadores sin DPV o los no fumadores, e intermedia a los fumadores con LFA. R5 y X5 fueron identificados como determinantes independientes de la CVRS en los fumadores sin LFA. Conclusiones: La DPV es frecuente en fumadores sin LFA, afectando a un tercio de los mismos, y condicionando de forma independiente su percepción de salud


Introduction: Small airway dysfunction (SAD) caused by smoking contributes to the early onset of airflow limitation (AFL), although its impact on patients’ perception of health is largely unknown. We aimed to evaluate the frequency of SAD in active smokers without AFL, and to compare health-related quality of life (HRQoL) of non-smokers, smokers without SAD, smokers with SAD, and smokers with AFL. Methods: A total of 53 active smokers without AFL, 20 smokers with AFL, and 20 non-smokers completed the SF-36 and EuroQoL questionnaires and performed impulse oscillometry and spirometry. Pulmonary parenchymal attenuation was determined in inspiration and expiration. SAD was determined to exist when resistance at 5Hz (R5), the difference between R5 and R20, and reactance area (AX) exceeded the upper limit of normal. Results: In total, 35.8% of smokers without AFL had SAD. No differences were detected in spirometric parameters or pulmonary attenuation between smokers with or without AFL and non-smokers. However, smokers with SAD had worse scores on HRQoL questionnaires than smokers without SAD or non-smokers, and scores compared to smokers with AFL were intermediate. R5 and X5 were identified as independent determinants of HRQoL in smokers without AFL. Conclusions: SAD is common in smokers without AFL, affecting one third of this population, and independently affecting their perception of health


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Manuseio das Vias Aéreas/métodos , Qualidade de Vida , Fumantes/estatística & dados numéricos , Inquéritos e Questionários , Oscilação da Parede Torácica/métodos , Abandono do Hábito de Fumar , Pacientes/classificação , não Fumantes/estatística & dados numéricos , Antropometria , Oscilometria/métodos , Espirometria
9.
Clin Exp Hypertens ; 42(2): 105-109, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-30810396

RESUMO

Objective: For repeated measurements of blood pressure (BP) using the auscultatory method, current guidelines recommend intervals of 1-2 minutes; however, evidence to support this recommendation is insufficient. In the present study, the effects of intervals among repeated BP measurements using the auscultatory method were evaluated.Methods: Systolic and diastolic BPs were measured using the auscultatory method in 37 participants. The measurements were repeated 5 times each at intervals of 15, 30, 60, 90, and 120 seconds. The changes in the BP along with the increasing the number of repetitions were assessed at each measurement interval using a linear mixed model.Results: With an increasing number of measurements, the systolic and diastolic BPs showed significant progressive decrease and increase (p < 0.05), respectively, when the measurement interval was 15 seconds. However, the precision of BP measurements was not affected by performing the measurements at intervals of 30 seconds or longer.Conclusion: Repeated BP measurements using the auscultatory method need to have an interval of at least 30 seconds, which is shorter than the intervals recommended by the current guidelines.


Assuntos
Pressão Sanguínea/fisiologia , Hipertensão/diagnóstico , Adulto , Idoso , Auscultação/métodos , Determinação da Pressão Arterial/métodos , Coleta de Dados , Diástole/fisiologia , Feminino , Nível de Saúde , Humanos , Hipertensão/fisiopatologia , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Oscilometria/métodos , Sístole/fisiologia , Adulto Jovem
10.
Blood Press Monit ; 25(1): 22-25, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31714349

RESUMO

OBJECTIVE: The aim of this study was to test whether ambulatory blood pressure monitoring (ABPM) in patients with atrial fibrillation is reliable as in patients with sinus rhythm. METHOD: This study included 92 persistent atrial fibrillation patients (50% females; mean age 70.49 ± 11.56 years) and 92 matched sinus rhythm patients (46% females; mean age 69.23 ± 12.63 years). The participants were examined simultaneously with 24-hour ABPM and 24-hour Holter electrocardiography. The mean 24-hour (24-hour-), daytime (day-) and nighttime (night-) BP, types of BP curve, morning systolic BP (SBP) surge (MBPS), the SD of BP readings and the coefficient of variability (the SD/mean BP × 100%) were compared between atrial fibrillation and sinus rhythm patients. RESULTS: No differences of 24-hour-, day- and night-SBP levels were observed between two groups. Meanwhile, the 24-hour-SD, day-SD and night-SD, as well as the coefficient of variability for SBP were also similar between two groups. There was no significant difference in the number of MBPS between the two groups. On diastolic BP (DBP), the similar 24 hour and day levels, the 24-hour-SD, day-SD and night-SD as well as the coefficient of variability were also similar between two groups. But the nighttime DBP levels and the night-SD were higher in atrial fibrillation than in sinus rhythm. CONCLUSION: ABPM provides data with similar SBP variability in patients with atrial fibrillation as in subject with normal cardiac rhythm. The ABPM on oscillometric method may be suitable for the atrial fibrillation patients, especially for the SBP evaluation.


Assuntos
Fibrilação Atrial/fisiopatologia , Monitorização Ambulatorial da Pressão Arterial/métodos , Pressão Sanguínea , Oscilometria/métodos , Idoso , Idoso de 80 Anos ou mais , Ritmo Circadiano/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
11.
Biomed Tech (Berl) ; 65(2): 121-131, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-31600137

RESUMO

Background and objective Spirometry, which is the most commonly used technique for asthma diagnosis, is often unsuitable for small children as it requires them to follow exact instructions and perform extreme inspiration and expiration maneuvers. In contrast, impulse oscillometry (IOS) is a child-friendly technique that could serve as an alternative pulmonary function test (PFT) for asthma diagnosis and control in children as it offers several advantages over spirometry. However, the complex test results of IOS may be difficult to be understood by practitioners due to its reliance on mechanical and electrical models of the human pulmonary system. Recognizing this reality, computer-aided decision systems could help to improve the utility of IOS. The main objective of this paper is to understand the current computer-aided classification research works on this topic. Methods This paper presents a methodological review of research works related to the computer-aided classification of peripheral airway obstruction using the IOS technique, which is focused on, but not limited to, asthmatic children. Publications that focused on computer-aided classification of asthma, peripheral dysfunction and/or small airway impairment (SAI) based on impulse oscillometric features were selected for this review. Results Out of the 34 articles that were identified using the selected scientific web databases and topic-related parameters, only eight met the eligibility criteria. The most relevant results of the articles reviewed are related to the performance of the different classifiers using static features which are solely based on the first pulmonary function testing measurements (IOS and spirometry). These results included an overall classifiers' accuracy performance ranging from 42.24% to 98.61%. Conclusion There is still a great opportunity to improve the utility of IOS by developing more computer-aided robust classifiers, specifically for the asthmatic children population as the classification studies performed to date (1) are limited in number, (2) include features derived from tests that are not optimally suitable for children, (3) are solely bi-class (mostly asthma and non-asthma) and therefore fail to include different degrees of peripheral obstruction for disease prevention and control and (4) lack of validation in cases that focus on multi-class classification of the different degrees of peripheral airway obstruction.


Assuntos
Asma/diagnóstico , Pulmão/fisiopatologia , Oscilometria/métodos , Espirometria/métodos , Criança , Humanos , Testes de Função Respiratória/métodos
12.
Medicine (Baltimore) ; 98(50): e18100, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31852069

RESUMO

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.


Assuntos
Assistência Ambulatorial , Pressão Sanguínea/fisiologia , Diabetes Mellitus/fisiopatologia , Hipertensão/fisiopatologia , Oscilometria/métodos , Análise de Onda de Pulso/métodos , Rigidez Vascular/fisiologia , Brasil/epidemiologia , Estudos Transversais , Diabetes Mellitus/diagnóstico , Diabetes Mellitus/epidemiologia , Feminino , Seguimentos , Humanos , Hipertensão/diagnóstico , Hipertensão/epidemiologia , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco , Sístole
13.
Rev Bras Enferm ; 72(suppl 3): 162-169, 2019 Dec.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31851249

RESUMO

OBJECTIVE: to compare blood pressure values obtained by auscultatory and oscillometric methods in different gestational periods, considering cuff width. METHOD: it is a cross-sectional and quasi-experimental study approved by the Research Ethics Committee. The sample consisted of 108 low-risk pregnant women. Blood pressure measurements were performed in gestational periods of 10-14, 19-22 and 27-30 weeks. RESULTS: The oscillometric device presented values similar to the auscultatory method in systolic blood pressure, but overestimated diastolic blood pressure. Underestimation of blood pressure occurred when using the standard width cuff rather than the correct width cuff in both measuring methods. CONCLUSION: Verification of brachial circumference and use of adequate cuffs in both methods are indispensable to obtain reliable blood pressure values in pregnant women. We recommend performance of additional studies to evaluate diastolic blood pressure overestimation by the Microlife 3BTO-A.


Assuntos
Determinação da Pressão Arterial/instrumentação , Oscilometria/instrumentação , Gestantes , Adulto , Auscultação/instrumentação , Auscultação/métodos , Determinação da Pressão Arterial/métodos , Determinação da Pressão Arterial/normas , Estudos Transversais , Feminino , Idade Gestacional , Humanos , Pessoa de Meia-Idade , Oscilometria/métodos , Oscilometria/normas , Gravidez
14.
Blood Press Monit ; 24(5): 213-220, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31490245

RESUMO

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.


Assuntos
Determinação da Pressão Arterial/métodos , Pressão Sanguínea/efeitos dos fármacos , Norepinefrina/farmacologia , Choque Cardiogênico/fisiopatologia , Vasoconstritores/farmacologia , Idoso , Idoso de 80 Anos ou mais , Pressão Arterial , Cateterismo , Estado Terminal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Monitorização Fisiológica , Norepinefrina/administração & dosagem , Oscilometria/métodos , Estudos Prospectivos , Vasoconstritores/administração & dosagem
15.
Adv Respir Med ; 87(4): 235-238, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31476011

RESUMO

Pulmonary function testing involves a battery of tests from the simple pulse oximetry to the cardiopulmonary exercise testing. Impulse oscillometry (IOS) is one of the newly described pulmonary function tests. It is based on the old principle of forced oscillatory technique modified and refined as per research and advances. It involves the use of sound waves during normal tidal breathing, which gives information on oscillatory pressure-flow relationships and eventually resistance and reactance. The resistance at 20 Hz (R20) represents the resistance of the large airways. The resistance at 5 Hz (R5) means the total airway resistance. (R5-R20) reflects resistance in the small airways. The reactance at 5 Hz (X5) indicates the elastic recoil of the peripheral airways. Resonant frequency and area of reactance are also measured. IOS has major uses in diagnosis and control of asthma in children and the elderly, where spirometry is otherwise normal. IOS has been studied in other respiratory diseases like COPD, ILD and supraglottic stenosis.


Assuntos
Oscilometria/normas , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Testes de Função Respiratória/normas , Humanos , Oscilometria/métodos , Reprodutibilidade dos Testes , Testes de Função Respiratória/métodos
16.
Sci Rep ; 9(1): 11618, 2019 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-31406190

RESUMO

Impedance, or oscillometry, measurements of the respiratory system can generate information about the function of the respiratory system not possible with traditional spirometry. There are currently several instruments on the market using different perturbations. We have compared a new respiratory oscillometry instrument, the tremoflo, with Impulse Oscillometry (IOS). Patients with a physician's diagnosis of chronic obstructive lung disease (COPD) and healthy subjects were recruited. They underwent assessment of respiratory function with oscillometry using the IOS and tremoflo devices and the resulting impedance data from the two methods were compared. The two devices were also tested against a reference respiratory phantom with variable resistances. Whereas both devices detected impairments in the patients' lung function commensurate with small airways pathology, the tremoflo appeared to be more sensitive than the IOS. We found systematic differences between the two instruments especially for reactance measurements where the area over the reactance curve (AX) was significantly lower with the IOS compared with the tremoflo (p < 0.001). Moreover, the agreement between the two devices was reduced with increasing severity of the disease as determined with a Bland-Altman test. Testing both instruments against a respiratory phantom unit confirmed that the resistance measured by the tremoflo compares closely with the known resistance of test loads, whereas the IOS' resistance correlated with a test load of 0.19, kPa.s.L-1 at higher loads it deviated significantly from the known resistance (p < 0.0028). We conclude that the absolute values measured with the two devices may not be directly comparable and suggest that differences in the calibration procedures might account for the differences.


Assuntos
Oscilometria/métodos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oscilometria/instrumentação , Testes de Função Respiratória
17.
Arq Bras Cardiol ; 113(2): 242-249, 2019 07 18.
Artigo em Inglês, Português | MEDLINE | ID: mdl-31340236

RESUMO

BACKGROUND: Psoriasis correlates with metabolic disorders, early atheromatosis and increased cardiovascular risk. OBJECTIVES: To assess markers of cardiovascular disease in psoriatic patients. METHODS: Cross-sectional, observational study involving 11 psoriatic participants and 33 controls. Anthropometric, biochemical, hemodynamic and imaging parameters were evaluated. Arterial stiffness was assessed by oscillometric measurement of the brachial artery. Intima-media thickness (IMT) and left ventricular diastolic function were assessed by Doppler echography and echocardiography. Between-group comparisons of numerical variables were performed by the Student's t-test or Wilcoxon Mann-Whitney test for independent samples. Significance level was set at 5%. RESULTS: Psoriatic patients showed increased pulse wave velocity (PWV) (9.1 ± 1.8 vs 8.0 ± 2 m/s, p = 0.033), IMT of the left common carotid artery (p = 0.018) and a higher percentage of patients above the 75th percentile according to the ELSA table when compared with controls (54.5 vs 18.2%, p = 0.045). Psoriatic patients also showed an increase in peripheral/central systolic blood pressure (137.1 ± 13.2 vs 122.3 ± 11.6 mmHg, p = 0.004)/(127 ± 13 vs 112.5 ± 10.4 mmHg, p = 0.005), peripheral/central diastolic blood pressure (89.9 ± 8.9 vs 82.2 ± 8, p = 0.022)/(91 ± 9.3 vs 82.2 ± 8.3, p = 0.014), total cholesterol (252 ± 43.5 vs 198 ± 39.8 mg/dL, p < 0.001), LDL cholesterol (167 ± 24 vs 118 ± 40.8 mg/dL, p < 0.001) and C-reactive protein (7.6 ± 35.4 vs 1 ± 1.2 mg/L p < 0.001) compared with controls. CONCLUSION: Psoriasis patients show increased PWV, IMT, peripheral and central blood pressures, and serum cholesterol and C-reactive protein levels, denoting a higher cardiovascular risk.


Assuntos
Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/fisiopatologia , Psoríase/complicações , Psoríase/fisiopatologia , Adulto , Idoso , Pressão Sanguínea/fisiologia , Artéria Braquial/fisiopatologia , Proteína C-Reativa/análise , Espessura Intima-Media Carotídea , Estudos de Casos e Controles , Colesterol/sangue , Estudos Transversais , Ecocardiografia Doppler , Humanos , Masculino , Pessoa de Meia-Idade , Oscilometria/métodos , Análise de Onda de Pulso , Valores de Referência , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Estatísticas não Paramétricas , Rigidez Vascular
18.
MAGMA ; 32(6): 679-692, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31218552

RESUMO

OBJECTIVE: A radiofrequency (RF) power amplifier is an essential component of any magnetic resonance imaging (MRI) system. Unfortunately, no commercial amplifier exists to fulfill the needs of the transmit array spatial encoding (TRASE) MRI technique, requiring high duty cycle, high RF output power and independently controlled multi-channel capability. Thus, an RF amplifier for TRASE MRI is needed. MATERIALS AND METHODS: A dual-channel RF power amplifier dedicated for TRASE at 0.22 T (9.27 MHz) was designed and constructed using commercially available components. The amplifier was tested on the bench and used a 0.22 T MRI system with a twisted solenoid and saddle RF coil combination capable of a single-axis TRASE. RESULTS: The amplifier is capable of sequential, dual-channel operation up to 50% duty cycle, 1 kW peak output and highly stable 100 µs RF pulse trains. High spatial resolution one-dimensional TRASE was obtained with the power amplifier to demonstrate its capability. CONCLUSION: The constructed amplifier is the first prototype that meets the requirements of TRASE rectifying limitations of duty cycle and timing presented by commercial RF amplifiers. The amplifier makes possible future high resolution in vivo TRASE MRI.


Assuntos
Processamento de Imagem Assistida por Computador/instrumentação , Processamento de Imagem Assistida por Computador/métodos , Imagem por Ressonância Magnética/instrumentação , Ondas de Rádio , Algoritmos , Amplificadores Eletrônicos , Eletrônica/instrumentação , Desenho de Equipamento , Aumento da Imagem/métodos , Modelos Lineares , Oscilometria/métodos , Imagens de Fantasmas , Reprodutibilidade dos Testes
19.
Wilderness Environ Med ; 30(3): 227-235, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31221602

RESUMO

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.


Assuntos
Determinação da Pressão Arterial/métodos , Vestuário , Oscilometria/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polônia , Estudos Prospectivos , Reprodutibilidade dos Testes , Estações do Ano , Medicina Selvagem , Adulto Jovem
20.
Allergol. immunopatol ; 47(3): 295-302, mayo-jun. 2019. graf
Artigo em Inglês | IBECS | ID: ibc-186493

RESUMO

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


No disponible


Assuntos
Humanos , Animais , Asma/diagnóstico , Pulmão/fisiologia , Pneumopatias/diagnóstico , Oscilometria/métodos , Testes de Função Respiratória/métodos
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