Neighborhood Walkability Index and Its Association With Indices of Childhood Obesity in Bengaluru, Karnataka

Background: The prevalence of childhood obesity is increasing in low-middle income countries like India. Built environment features such as walkability can influence weight-related outcomes but data from developing countries are scanty. Objective: To develop population level walkability index in urban Bengaluru, and examine its association with indices of childhood obesity in school children. Study Design: Nested cross-sectional study based on a cohort. Participants: Normal healthy children aged 6 to 15 years from urban schools in Bengaluru. The children were stratified into different land use classification such as residential, commercial and open space based on residential address. Methods: Anthropometric data, body composition data, measured using air displacement plethysmography. Outcomes: Walkability index derived using residential density, street connectivity and land-use mix environment variables. Results: The mean (SD) of age, body mass index (BMI), BMI zscore and percentage body fat (% Body fat) of 292 (50% boys) children were 10.8 (2.9) year, 17.4 (3.3) kg/m2, -0.27 (1.35) and 20.9% (8.8), respectively. The mean (SD) walkability index was 16.5, which was negatively associated with BMI (slope -0.25 and -0.08) and percentage body fat (slope -0.47 and -0.21) for age 5 and 10 years, respectively in children, but the effects decreased with increasing age. Conclusions: The findings of this pilot study suggest that the neighborhood walkability may be associated with the obesity indices in younger children. Future longitudinal studies are needed to understand how built environment affects health and body composition of children in India and other low-middle income countries.

Role of machine learning techniques in classification of peripheral pulse morphology

Recording of peripheral pulse serves as a very important and essential non-invasive tool used widely by doctors for the diagnosis of various diseases. The morphology of pulse is seen to vary as a function of time in a given individual and also from individual to individual. There are many variations in morphological patterns of peripheral pulse in different disease conditions, which lead to difficulty in accurate diagnosis. The peripheral pulse waveforms are extracted from radial arteries as time series data using a peripheral pulse analyzer which is designed on the principle of impedance plethysmography. It was first introduced by Nyober in the mid-nineteen hundreds and ameliorated further by Kubicek. It involves the recording of the instantaneous blood volume by the measurement of electrical impedance as a function of time. Therefore, the study of peripheral pulse morphology has gained much attention in the past few years among researchers. Physiological variability is one of the recent investigations added during the last two decades for the objective assessment of autonomic function and the assessment of prognosis in severe sicknesses namely myocardial infarction, diabetic neuropathy, etc. In addition to heart rate variability studied worldwide, few researchers have studied blood pressure variability and peripheral blood flow variability. In this computer era, artificial intelligence and machine learning techniques have become more important day-by- day, and different types of algorithms were used for the identification of hidden patterns from plethysmographic observations on the radial pulse such as support vector machine as well as crisp and fuzzy clustering. Eight patterns were classified with a yield of 80%–90% and helped with the diagnosis of disorders such as myocardial infarction, pulmonary tuberculosis, coronary artery disorders, cirrhosis of the liver, and bronchial asthma. This paper briefly describes the use of machine learning techniques for the classification of peripheral pulse morphologies.

Pulse arrival time: Measurement and clinical applications

Pulse arrival time is the time elapsed between the R-wave of electrocardiogram and systolic peak in peripheral pulse obtained by any of the plethysmographic methods. Similarly, differential pulse arrival time, also known as pulse transit time, is the time elapsed between systolic peaks of proximal and distal peripheral pulse recordings in an extremity. Distance between the proximal and distal site in the extremity (in meters) divided by differential pulse arrival time (in seconds) gives arterial pulse wave velocity in the limb segment. Differential pulse arrival time has been used to discriminate between an aortic or arterial block from generalized atherosclerosis in aortic and arterial occlusive diseases for nearly four decades. All along there have been efforts to monitor beat-to-beat blood pressure with the help of these time intervals and other pulse parameters. Encouraging correlation has been observed with that obtained by Finapres. Recently pulse arrival time has been explored for the prompt detection of sudden hypertensive episodes during laryngeal microsurgery, for detection of mental stress, monitoring of baroreflex sensitivity, and real-time monitoring of blood pressure. This paper briefly describes the measurement technique of pulse arrival time and an overview of its clinical applications.

Gestational age, intrauterine growth and body composition at 11 years of age / Idade gestacional, crescimento intrauterino e composição corporal aos 11 anos de idade

ABSTRACT OBJETIVE To assess the association of gestational age (GA) and intrauterine growth with body composition at 11 years of age. METHOD Analysis of data from the 2004 Pelotas birth cohort, whose outcomes were fat mass (FM, kg), fat mass index (FMI, kg/m2), fat-free mass (FFM, kg), fat-free mass index (FFMI, kg/m2) - measured by air displacement plethysmography - and body mass index for age (BMI/age, Z-score). The exposures of interest were the gestational index (GA) of infants born at less than 33 weeks, from 34 to 36 and from 37 to 41, and intrauterine growth categorized as small (SGA), adequate (AGA) and large (LGA) for gestational age. Analysis of variance was used to compare means and linear regression was used to assess the strength of association. The analyses were adjusted according to variables collected at birth, such as monthly family income, maternal characteristics - education, age, pre-gestational body mass index (BMI), weight gain during pregnancy, smoking during pregnancy, type of delivery, and parity - and adolescent characteristics - skin color and birth weight. For analysis, FM and FMI underwent logarithmic transformation due to data asymmetry. RESULTS A total of 3,401 adolescents were analyzed, including boys and girls born at less than 33 weeks, with lower FM and FFM means than those born at term. However, in the adjusted analyses, there was no association between GA and any of the outcomes in either sex. LGA boys had a 10.5% higher FMI (p = 0.026) and +0.3 BMI/age Z-score (p = 0.019) as compared to AGA boys, and LGA girls had +0.3 kg/m 2 of FFMI (p = 0.039) than AGA girls. CONCLUSION GA was not associated with body composition at 11 years of age. However, LGA boys had higher BMI and BMI/age Z-score, and LGA girls had higher FFMI than AGA girls.

RESUMO OBJETIVO Avaliar a associação da idade gestacional (IG) e crescimento intrauterino com a composição corporal aos 11 anos de idade. MÉTODO Análise de dados da coorte de nascimentos de Pelotas de 2004, cujos desfechos foram massa gorda (MG, kg), índice de massa gorda (IMG, kg/m2), massa livre de gordura (MLG, kg), índice de massa livre de gordura (IMLG, kg/m2) - medidos por pletismografia por deslocamento de ar -, e índice de massa corporal para idade (IMC/Idade, escore-Z). Sendo as exposições de interesse o índice gestacional (IG) de nascidos com menos de 33 semanas, de 34 a 36 e de 37 a 41, e crescimento intrauterino categorizado em pequeno para a idade gestacional (PIG), adequado (AIG) e grande (GIG). Para comparar médias, utilizou-se análise de variância e, para avaliar a força de associação, regressão linear. As análises foram ajustadas de acordo com variáveis coletadas ao nascer, como renda familiar mensal, características maternas - escolaridade, idade, índice de massa corporal (IMC) pré-gestacional, ganho de peso na gestação, tabagismo na gestação, tipo de parto e paridade - e características dos adolescentes - cor da pele e peso ao nascer. Para análise, o MG e o IMG sofreram transformação logarítmica devido a assimetria dos dados. RESULTADOS Foram analisados 3.401 adolescentes, entre meninos e meninas nascidos com menos de 33 semanas, com médias de MG e MLG menores que as dos nascidos(as) a termo. Porém, nas análises ajustadas, não houve associação entre IG e qualquer um dos desfechos em ambos os sexos. Meninos GIG apresentaram IMG 10,5% maior (p = 0,026) e +0,3 escore-Z de IMC/Idade (p = 0,019) em relação aos AIG, e meninas GIG apresentaram +0,3 kg/m2 de IMLG (p = 0,039) do que as AIG. CONCLUSÃO A IG não se associou à composição corporal aos 11 anos. Entretanto, meninos GIG apresentaram maiores IMG e escore-Z de IMC/Idade e meninas GIG, maior IMLG, quando comparados aos AIG.

Comportamiento de volúmenes pulmonares estáticos por pletismografía en enfermedad pulmonar obstructiva crónica con disociación clínico-espirométrica / Behavior of static lung volumes due to plethysmography in chronic obstructive pulmonary disease with clinical-spirometric dissociation

Introducción: La enfermedad pulmonar obstructiva crónica es un problema sanitario mundial por su elevada prevalencia, morbilidad y cuantioso costo económico. Objetivo: Caracterizar mediante la pletismografía a los pacientes con diagnóstico de enfermedad pulmonar obstructiva crónica que presentaron una discrepancia clínica espirométrica. Métodos: Se realizó un estudio descriptivo y transversal en 33 pacientes con diagnóstico de enfermedad pulmonar obstructiva crónica que acudieron a consulta externa del Hospital Neumológico Benéfico Jurídico y el Centro de Investigaciones Clínicas. Se les realizaron volúmenes pulmonares por pletismografía corporal y espirometría en el período comprendido de noviembre 2016 a marzo 2018. Resultados: El sexo masculino (69,7 por ciento) resultó el más frecuente y el grupo de edad predominante fue mayor de 65 años (60,6 por ciento). El 41,2 por ciento de los pacientes presentaron grado de obstrucción moderadamente severo. La capacidad pulmonar total y el volumen residual fueron normales (72,7 por ciento y 42,5 por ciento) respectivamente. El 43,8 por ciento de los pacientes presentaron hiperinsuflación leve. El grado 3 de disnea fue el que predominó en los pacientes. El 12,1 por ciento de los pacientes presentaron aumento del volumen residual dado por atrapamiento aéreo grave con la disminución del volumen espiratorio forzado en el primer segundo. Conclusiones: El comportamiento de los volúmenes pulmonares por pletismografía corporal en la enfermedad pulmonar obstructiva crónica con disociación clínico-espirométrica, evidenció la disminución del volumen espiratorio forzado en el primer segundo y el aumento del volumen residual relacionándose con el grado de disnea(AU)

Introduction: Chronic obstructive pulmonary disease is a global health problem due to its high prevalence, morbidity and high economic cost. Objective: By using plethysmography, to describe patients with diagnosis of chronic obstructive pulmonary disease that had spirometric clinical discrepancy. Methods: A descriptive and cross-sectional study was carried out in 33 patients with diagnosis of chronic obstructive pulmonary disease who attended the outpatient clinic at Benéfico Jurídico Pneumologic Hospital and the Clinical Research Centre. Lung volumes were performed by body plethysmography and spirometry from November 2016 to March 2018. Results: The male sex (69.7 percent) was the most frequent and the predominant age group was older than 65 years (60.6 percent). 41.2 percent of the patients had moderately severe degree of obstruction. Total lung capacity and residual volume were normal, 72.7 percent and 42.5 percent, respectively. 43.8 percent of the patients had mild hyperinflation. Grade 3 dyspnea was the one that predominated in the patients. 12.1 percent of the patients showed increased residual volume due to severe air trapping with decreased forced expiratory volume in the first second. Conclusions: The behavior of lung volumes by body plethysmography in chronic obstructive pulmonary disease with clinical-spirometric dissociation, evidenced decrease in forced expiratory volume in the first second and increased in residual volume related to the degree of dyspnea(AU)

Quantitative analysis of breathing patterns based on wearable systems / 生物医学工程学杂志

Breathing pattern parameters refer to the characteristic pattern parameters of respiratory movements, including the breathing amplitude and cycle, chest and abdomen contribution, coordination, etc. It is of great importance to analyze the breathing pattern parameters quantificationally when exploring the pathophysiological variations of breathing and providing instructions on pulmonary rehabilitation training. Our study provided detailed method to quantify breathing pattern parameters including respiratory rate, inspiratory time, expiratory time, inspiratory time proportion, tidal volume, chest respiratory contribution ratio, thoracoabdominal phase difference and peak inspiratory flow. We also brought in "respiratory signal quality index" to deal with the quality evaluation and quantification analysis of long-term thoracic-abdominal respiratory movement signal recorded, and proposed the way of analyzing the variance of breathing pattern parameters. On this basis, we collected chest and abdomen respiratory movement signals in 23 chronic obstructive pulmonary disease (COPD) patients and 22 normal pulmonary function subjects under spontaneous state in a 15 minute-interval using portable cardio-pulmonary monitoring system. We then quantified subjects' breathing pattern parameters and variability. The results showed great difference between the COPD patients and the controls in terms of respiratory rate, inspiratory time, expiratory time, thoracoabdominal phase difference and peak inspiratory flow. COPD patients also showed greater variance of breathing pattern parameters than the controls, and unsynchronized thoracic-abdominal movements were even observed among several patients. Therefore, the quantification and analyzing method of breathing pattern parameters based on the portable cardiopulmonary parameters monitoring system might assist the diagnosis and assessment of respiratory system diseases and hopefully provide new parameters and indexes for monitoring the physical status of patients with cardiopulmonary disease.

Pulmonary capacity of patients with total traumatic injury of the brachial plexus submitted to neurotization with the phrenic nerve: a case series / Capacidade pulmonar de pacientes com lesão traumática total do plexo braquial submetidos à neurotização com o nervo frênico: uma série de casos

Total traumatic injury often requires surgical intervention such as neurotization using the phrenic nerve with the aim to recover the elbow function. However, its repercussions on the respiratory kinematics are unknown. Objective: To evaluate the ribcage volume in tricompartments division, kinematics of Duty Cycle, and shortening velocity of the respiratory muscles after nerve phrenic transfer. Methods: Five participants (4 male), aged 18 to 40 years old (32±2), diagnosed with total brachial plexus injury and with nerve phrenic transfer. The optoelectronic plethysmography (OEP) was the instrument to evaluate volume in quiet breathing (QB), inspiratory capacity (IC) and vital capacity (VC) of the rib cage in its tricompartments division (pulmonary rib cage, abdominal rib cage and abdomen rib cage) and in each hemithorax, as well as the shortening velocity of the respiratory muscles, and respiratory rate. Assessments occurred 30 days prior and 30 days after surgery. Results: There was a decrease in the total compartmental distribution in QB with statistical difference only in the abdominal compartment (p <0.05). Four patients showed a reduction in the shortening speed of the left diaphragm muscle. It was not possible to perform a group analysis of respiratory kinematics and volumes in CV, IC due to the variation found in each patient analyzed. Conclusion: There was a reduction in volume in the rib cage as well as a change in the speed of shortening of the respiratory muscles after the transfer of the phrenic nerve one month after surgery.

A lesão traumática total freqüentemente requer intervenção cirúrgica, como neurotização usando o nervo frênico, com o objetivo de recuperar a função do cotovelo. No entanto, suas repercussões na cinemática respiratória são desconhecidas. Objetivo: Avaliar o volume da caixa torácica na divisão dos tricompartimentos, a cinemática do Duty Cycle e a velocidade de encurtamento dos músculos respiratórios após a transferência do nervo frênico. Métodos: Cinco participantes (4 do sexo masculino), com idade entre 18 e 40 anos (32 ± 2), com diagnóstico de lesão total do plexo braquial e transferência do nervo frênico. A pletismografia optoeletrônica (OEP) foi o instrumento para avaliar o volume na respiração silenciosa (QB), a capacidade inspiratória (IC) e a capacidade vital (VC) da caixa torácica em sua divisão tricompartimental (caixa torácica pulmonar, caixa torácica abdominal e caixa torácica do abdômen ) e em cada hemitórax, bem como a velocidade de encurtamento dos músculos respiratórios e a frequência respiratória. As avaliações ocorreram 30 dias antes e 30 dias após a cirurgia. Resultados: Houve diminuição da distribuição compartimental total no QB com diferença estatística apenas no compartimento abdominal (p <0,05). Quatro pacientes apresentaram redução da velocidade de encurtamento do músculo diafragma esquerdo. Não foi possível realizar uma análise de grupo da cinemática respiratória e dos volumes em CV, IC devido à variação encontrada em cada paciente analisado. Conclusão: Houve redução do volume da caixa torácica e também alteração da velocidade de encurtamento dos músculos respiratórios após a transferência do nervo frênico um mês após a cirurgia.

Evaluation of anthropometric equations developed to estimate neonates body composition: a systematic review / Avaliação de equações antropométricas desenvolvidas para estimar a composição corporal de neonatos: uma revisão sistemática

Abstract This article aims to evaluate the anthropometric equations developed by selected studies in order to estimate the body composition of neonates. The systematic review consisted in the research of published articles in the following databases: PubMed, Brazilian Virtual Health Library, Embase and ScienceDirect by utilizing the following descriptors: "fat mass, fat free mass, anthropometry, air displacement plethysmography, validation, neonate". For doing so, the PRISMA protocol has been utilized. The bibliographical research resulted in 181 articles. However, only eight were selected for the present review because repetition in different databases and having been performed in adults, during pregnancy, in athletes, in preterm and children. There was discrepancy in terms of study method, mainly over the variables of the anthropometric equations, age and ethnicity of the neonates. All studies used the plethysmography method as a reference apart from one study. Only four studies had their equations validated. The studies that developed anthropometric models for estimating the body composition of neonates are scarce, and the use of these equations needs to be conducted carefully in order to avoid errors in nutritional diagnosis.

Resumo Este artigo tem por objetivo avaliar as equações antropométricas desenvolvidas pelos estudos selecionados para estimar a composição corporal de neonatos. A revisão sistemática consistiu na busca de artigos publicados nas bases de dados PubMed, Biblioteca Virtual de Saúde, Embase e ScienceDirect utilizando os seguintes descritores: "fat mass, fat free mass, anthropometry, air displacement plethysmography, validation, neonate". Para isso foi utilizado o protocolo PRISMA. A busca bibliográfica resultou em 181 artigos. Entretanto, apenas oito foram selecionados para compor a presente revisão por estarem presentes em outras bases de dados, por terem sido realizados com adultos, atletas, prematuros e crianças. Houve discrepância em relação aos métodos dos estudos, sobretudo no que diz respeito as variáveis que compuseram as equações antropométricas. Com exceção de um artigo, todos utilizaram a pletismografia como método de referência. Apenas quatro estudos tiveram suas equações validadas. Além de serem escassos os estudos que desenvolveram equações antropométricos para estimar a composição corporal de neonatos, o uso desses modelos deve ser realizado com cautela para evitar erros no diagnóstico nutricional dos neonatos.

Body composition among long distance runners

SUMMARY OBJECTIVE The current study aimed to examine the body composition of adult male ultra-trail runners (UTR) according to their level of participation (regional UTR-R, vs. national UTR-N). METHODS The sample was composed of 44 adult male UTR (aged 36.5±7.2 years; UTR-R: n=25; UTR-N: n=19). Body composition was assessed by air displacement plethysmography, bioelectrical impedance, and dual-energy X-ray absorptiometry. In addition, the Food Frequency Questionnaire (FFQ) was applied. A comparison between the groups was performed using independent samples t-test. RESULTS Significant differences between groups contrasting in the competitive level were found for chronological age (in years; UTR-R: 38.8±8.2 vs. UTR-N: 33.5±4.1); body density (in L.kg-1; UTR-R: 1.062±0.015 vs. UTR-N: 1.074±0.009); and fat mass (in kg; UTR-R: 12.7±6.8 vs. UTR-N: 7.6±2.7). CONCLUSION UTR-N were younger, presented higher values for body density, and had less fat mass, although no significant differences were found for fat-free mass. The current study evidenced the profile of long-distance runners and the need for weight management programs to regulate body composition.

RESUMO OBJETIVO O presente estudo objetivou examinar a composição corporal dos corredores de ultra-trail (UTR) e, adicionalmente, comparar dois grupos de acordo com o nível de participação (Regional vs. Nacional, respectivamente UTR-R e UTR-N). MÉTODOS A amostra foi composta por 44 corredores adultos masculinos (36,5±7,2 anos de idade; UTR-R: n=25; UTR-N: n=19). A composição corporal foi avaliada recorrendo à pletismografia de ar deslocado, bioimpedância elétrica e absorciometria de raios X de dupla energia. Adicionalmente, foi utilizado o Questionário de Frequência Alimentar. A comparação entre grupos foi realizada com base na prova t-student para amostras independentes. RESULTADOS Foram encontradas diferenças significativas por nível de competição para as seguintes variáveis dependentes: idade cronológica (em anos; UTR-R: 38,8±8,2 vs. UTR-N: 33,5±4,1); densidade corporal (em kg/L; UTR-R: 1,062±0,015 L/kg vs. UTR-N: 1,074±0,009); massa gorda (em kg; UTR-R: 12,7±6,8 kg vs. UTR-N: 7,6±2,7). CONCLUSÃO Os UTR-N tendem a ser mais jovens e apresentam valores superiores de densidade corporal e, consequentemente, valores menores de massa gorda, sendo a massa isenta de gordura semelhante entre os grupos. O presente estudo determinou o perfil dos corredores adultos masculinos de longa distância (ultra-trail), realçando a importância de uma cuidadosa regulação da massa corporal.

Clinical and functional correlations of the difference between slow vital capacity and FVC / Correlação clínica e funcional da diferença entre capacidade vital lenta e CVF

ABSTRACT Objective: To evaluate the relationship that the difference between slow vital capacity (SVC) and FVC (ΔSVC-FVC) has with demographic, clinical, and pulmonary function data. Methods: This was an analytical cross-sectional study in which participants completed a respiratory health questionnaire, as well as undergoing spirometry and plethysmography. The sample was divided into two groups: ΔSVC-FVC ≥ 200 mL and ΔSVC-FVC < 200 mL. The intergroup correlations were analyzed, and binomial logistic regression analysis was performed. Results: The sample comprised 187 individuals. In the sample as a whole, the mean ΔSVC-FVC was 0.17 ± 0.14 L, and 61 individuals (32.62%) had a ΔSVC-FVC ≥ 200 mL. The use of an SVC maneuver reduced the prevalence of nonspecific lung disease and of normal spirometry results by revealing obstructive lung disease (OLD). In the final logistic regression model (adjusted for weight and body mass index > 30 kg/m2), OLD and findings of air trapping (high functional residual capacity and a low inspiratory capacity/TLC ratio) were predictors of a ΔSVC-FVC ≥ 200 mL. The chance of a bronchodilator response was found to be greater in the ΔSVC-FVC ≥ 200 mL group: for FEV1 (OR = 4.38; 95% CI: 1.45-13.26); and for FVC (OR = 3.83; 95% CI: 1.26-11.71). Conclusions: The use of an SVC maneuver appears to decrease the prevalence of nonspecific lung disease and of normal spirometry results. Individuals with a ΔSVC-FVC ≥ 200 mL, which is probably the result of OLD and air trapping, are apparently more likely to respond to bronchodilator administration.

RESUMO Objetivo: Avaliar a relação da diferença entre a capacidade vital lenta (CVL) e CVF (ΔCVL-CVF) com dados demográficos, clínicos e de função pulmonar. Métodos: Estudo analítico, transversal, no qual os participantes responderam a um questionário de saúde respiratória e foram submetidos a espirometria e pletismografia. A amostra foi dividida em dois grupos: ΔCVL-CVF ≥ 200 mL e ΔCVL-CVF < 200 mL. Foram realizadas análises de correlações entre os grupos e de regressão logística binominal. Resultados: Foram selecionados 187 indivíduos. Na amostra total, a média da ΔCVL-CVF foi de 0,17 ± 0,14 L. Na amostra, 61 indivíduos (32,62%) apresentaram ΔCVL-CVF ≥ 200 mL. O uso da manobra expiratória lenta reduziu a prevalência de distúrbio ventilatório inespecífico e resultados espirométricos normais, ao revelar distúrbio ventilatório obstrutivo (DVO). DVO e achados de aprisionamento aéreo (capacidade residual funcional elevada e capacidade inspiratória/CPT reduzida) foram preditores de ΔCVL-CVF ≥ 200 mL no modelo final da regressão logística (ajustada para peso e índice de massa corpórea > 30 kg/m2). Foi observada maior chance de resposta ao broncodilatador no grupo ΔCVL-CVF ≥ 200 mL: VEF1 (OR = 4,38; IC95%: 1,45-13,26) e CVF (OR = 3,83; IC95%: 1,26-11,71). Conclusões: O uso da manobra expiratória lenta diminuiu a prevalência de distúrbio ventilatório inespecífico e de resultados espirométricos normais, podendo a ΔCVL-CVF ≥ 200 mL ser resultado de DVO e aprisionamento aéreo, tendo maior chance de resposta ao broncodilatador.

Characterization of the severity of dyspnea in patients with bronchiectasis: correlation with clinical, functional, and tomographic aspects / Caracterização da gravidade de dispneia em pacientes com bronquiectasias: correlação com aspectos clínicos, funcionais e tomográficos

ABSTRACT Objective: To characterize a population of patients with bronchiectasis, correlating clinical, radiological, and functional aspects with the severity of dyspnea. Methods: This was a cross-sectional study involving adult patients with HRCT-confirmed bronchiectasis, categorized according to the severity of dyspnea (as being mildly or severely symptomatic, on the basis of the modified Medical Research Council scale). We correlated the severity of dyspnea with clinical parameters, functional parameters (spirometry values, lung volumes, and DLCO), and CT parameters. Results: We evaluated 114 patients, 47 (41%) of whom were men. The median age (interquartile range) was 42 years (30-55 years). The most common form was idiopathic bronchiectasis. Of the 114 patients, 20 (17.5%) were colonized with Pseudomonas aeruginosa and 59 (51.8%) were under continuous treatment with macrolides. When we applied the Exacerbation in the previous year, FEV1, Age, Colonization, Extension, and Dyspnea score, the severity of dyspnea was categorized as moderate in 54 patients (47.4%), whereas it was categorized as mild in 50 (43.9%) when we applied the Bronchiectasis Severity Index. The most common lung function pattern was one of obstruction, seen in 95 patients (83.3%), and air trapping was seen in 77 patients (68.7%). The prevalence of an obstructive pattern on spirometry was higher among the patients with dyspnea that was more severe, and most functional parameters showed reasonable accuracy in discriminating between levels of dyspnea severity. Conclusions: Patients with bronchiectasis and dyspnea that was more severe had greater functional impairment. The measurement of lung volumes complemented the spirometry data. Because bronchiectasis is a complex, heterogeneous condition, a single variable does not seem to be sufficient to provide an overall characterization of the clinical condition.

RESUMO Objetivo: Caracterizar uma população de portadores de bronquiectasias e correlacionar aspectos clínicos, radiológicos e funcionais com a gravidade da dispneia. Métodos: Estudo transversal realizado em adultos, portadores de bronquiectasias confirmadas por TCAR, categorizados de acordo com a gravidade da dispneia (pacientes pouco e muito sintomáticos), correlacionando-os com seus parâmetros clínicos, funcionais (espirometria, volumes pulmonares e DLCO) e tomográficos. Resultados: Foram avaliados 114 pacientes (47 homens, 41%). A mediana (intervalo interquartil) de idade foi de 42 (30-55) anos. A etiologia mais frequente foi idiopática. Em relação à colonização, 20 pacientes (17,5%) eram colonizados por Pseudomonas aeruginosa e grande parte fazia uso de macrolídeo continuamente (51,8%). Quanto à gravidade da dispneia, ela foi considerada moderada em 54 pacientes (47,4%) pelo escore Exacerbation in previous year, FEV1, Age, Colonization, Extension, and Dyspnea e leve em 50 (43,9%) pelo Bronchiectasis Severity Index. O padrão funcional mais encontrado foi distúrbio ventilatório obstrutivo (em 83%), e 68% apresentavam aprisionamento aéreo. Pacientes com maior grau de dispneia apresentaram maior prevalência de distúrbio obstrutivo na espirometria, e a maioria dos parâmetros funcionais apresentaram acurácia razoável em discriminar a gravidade da dispneia. Conclusões: Pacientes com bronquiectasias e maior gravidade da dispneia apresentaram um comprometimento funcional mais expressivo. A medida de volumes pulmonares complementou os dados da espirometria. Por se tratar de uma condição complexa e heterogênea, uma única variável parece não ser suficiente para caracterizar a condição clínica de forma global.

A Light Adaptive Heart Rate Detection Method Based on Webcam / 中国医疗器械杂志

In order to extract the pulse wave signal of blood volume effectively in the case of uneven light, a light-adaptive heart rate detection method based on webcam was proposed. In this method, adaptive gamma transform is applied to face image sequence to eliminate the influence of illumination. The pulse wave source signal was extracted from the forehead area and the blood volume pulse wave was obtained by wavelet filtering. The heart rate is estimated by Fourier transform analysis. The Bland-Altman analysis indicates that the method used in this paper is in good agreement with the measurement results of the electronic sphygmomanometer, and the adaptive gamma transformation used in this paper eliminates the influence of light interference, and the measurement error of heart rate is significantly reduced, which is completely able to meet the requirements of daily heart rate monitoring.

Evaluation of lung function in patients submitted to total laryngectomy / Avaliação da função pulmonar em pacientes submetidos à laringectomia total

Abstract Introduction: The post-laryngectomy state is characterized by several alterations in lung function. A reliable estimation of lung function can be very useful in laryngectomees to prevent postoperative complications and to evaluate the results of the treatment. Objective: Characterize the presence of respiratory functional disorders and the functional pattern of laryngectomees through the use of an extratracheal device. Methods: This transversal study included 50 patients submitted to total laryngectomy at least 6 months prior to this investigation, as the treatment of choice for laryngeal cancer. Results: 56% percent of the participants had altered breathing pattern, distributed as follows: 14 with obstructive pattern with no air trapping, 11 with obstructive pattern with air trapping and only 3 with restrictive pattern. On average, the diffusion decreased (74.3%) and airway resistance increased (121.7%) when compared to the expected average values for the Brazilian individuals. Conclusion: Most patients submitted to total laryngectomy present altered lung function, usually the obstructive type, frequently associated to a history of smoking.

Resumo Introdução: A condição pós-laringectomia é caracterizada por várias alterações na função pulmonar. Uma estimativa confiável da função pulmonar pode ser muito útil em pacientes laringectomizados para prevenir complicações após as intervenções cirúrgicas e avaliar os resultados do tratamento. Objetivo: Caracterizar a presença de distúrbios funcionais respiratórios e o padrão funcional de pacientes laringectomizados através do uso de um dispositivo extratraqueal. Método: Estudo transversal que incluiu 50 pacientes submetidos à laringectomia total pelo menos seis meses antes desta investigação, como tratamento de escolha para o câncer de laringe. Resultados: Dos participantes, 56% apresentavam padrão respiratório alterado, assim distribuídos: 14 com padrão obstrutivo sem aprisionamento aéreo, 11 com padrão obstrutivo e aprisionamento aéreo e apenas três com padrão restritivo. Em média, verificou-se que a difusão encontrava-se diminuída (74,3%) e a resistência das vias aéreas aumentada (121,7%) em relação aos resultados esperados em brasileiros. Conclusão: A maioria dos pacientes submetidos à laringectomia total apresenta função pulmonar alterada, do tipo obstrutiva, quase sempre associada a história de tabagismo.

Comparison of bioelectrical impedance analysis and air displacement plethysmography / Comparación de análisis de impedancia bioeléctrica y pletismografía de desplazamiento de aire

The measurement of body composition has become an important component in the diagnosis of health, physical conditioning and nutritional status. The aim of this study was to compare two methods of detecting body composition, bioelectrical impedance and air displacement plethysmography for athletes and non-athletes. Specifically, we compared the parameters as fat mass, fat free mass and the value of basal metabolic rate. A sample size of 52 men (age 26.2 ± 5.4 years) that included a group of mixed martial arts (MMA) fighters (n = 31, age 27.2 ± 5.5 years) and a group of the non-athletes (n =21, age 24.6 ± 5.1 years). Both groups were measured by bioelectrical impedance and air displacement plethysmography. Significant differences in % body fat (p<0.05) and fat-free mass (p<0.05) were noted between bioelectrical impedance and air displacement plethysmography of non-athletes, but there were no significant differences for athletes. Furthermore, there was a significant difference (p<0.001) of basal metabolic rate between bioelectrical impedance and air displacement plethysmography, but the correlation with fat free mass was very strong for both methods. Therefore, the use of bioelectrical impedance and air displacement plethysmography may be useful for detecting changes in body composition, but their accuracy is controversial and for this reason we recommend using only one method and not combining them.

La medición de la composición corporal se ha convertido en un componente importante en el diagnóstico de la salud, el acondicionamiento físico y el estado nutricional. El objetivo de este estudio fue comparar dos métodos para detectar la composición corporal, la impedancia bioeléctrica y la pletismografía de desplazamiento de aire para atletas y no atletas. Específicamente, comparamos los parámetros como masa grasa, masa libre de grasa y el valor de la tasa metabólica basal. Un tamaño de muestra de 52 hombres (edad 26,2 ± 5,4 años) de un grupo de luchadores de artes marciales mixtas (MMA) (n = 31, edad 27,2 ± 5,5 años) y un grupo de no deportistas (n = 21, edad 24,6 ± 5,1 años). Ambos grupos se midieron por impedancia bioeléctrica y pletismografía de desplazamiento de aire. Se observaron diferencias significativas en el porcentaje de grasa corporal (p<0,05) y la masa libre de grasa (p<0,05) entre la impedancia bioeléctrica y la pletismografía de desplazamiento de aire de los no deportistas, sin embargo no hubo diferencias significativas en los atletas. Además, se observó una diferencia significativa (p<0,001) de la tasa metabólica basal entre la impedancia bioeléctrica y la pletismografía de desplazamiento de aire, pero la correlación con la masa libre de grasa fue importante para ambos métodos. Por lo tanto, el uso de la pletismografía de impedancia bioeléctrica y desplazamiento de aire puede ser útil para detectar cambios en la composición corporal, pero su precisión es controvertida por lo que recomendamos usar solo un método y no una combinación de ambos.

Preoperative “R wave amplitude variation” on electrocardiogram predicts severe hypovolemia

Preoperative fasting is essential to prevent aspiration and associated complications. However, quite often patients end up fasting for 12 h or more due to changes in the operating room schedules, delays, and postponements. Preoperative fasting may lead to a fluid deficit, which may contribute to perioperative discomfort and morbidity. We report a case of 44-year-old female posted for total mastectomy with axillary clearance for carcinoma breast, with prolonged fasting where preoperative R wave amplitude variation along with associated changes in the plethysmograph was noticed on the monitor. 500 milliliters of lactated ringer solution was administered before induction of anesthesia, by the time R wave amplitude variation decreased. Variations in plethysmography became normal after 1 L of fluid administration after induction of anesthesia. Gross R wave amplitude variation is not a very common finding and may predict severe hypovolemia in preoperative area in prolonged fasting patients.

Reference values for pulmonary volumes by plethysmography in a Brazilian sample of white adults / Valores de referência para volumes pulmonares por pletismografia em uma amostra brasileira de adultos da raça branca

ABSTRACT Objective: To derive reference values for healthy white Brazilian adults who have never smoked and to compare the obtained values with reference values derived by Crapo and by Neder. Methods: Reference equations by quantile regressions were derived in 122 men and 122 women, non-obese, living in seven cities in Brazil. Age ranged from 21 to 92 years in women and from 25 to 88 years in men. Lung function tests were performed using SensorMedics automated body plethysmographies according ATS/ERS recommendations. Lower and upper limits were derived by specific equations for 5 and 95 percentiles. The results were compared to those suggested by Crapo in 1982, and Neder in 1999. Results: Median values for total lung capacity (TLC) were influenced only by stature in men, and by stature and age in women. Residual volume was influenced by age and stature in both genders. Weight was directly related to inspiratory capacity and inversely with functional residual capacity and expiratory reserve volume in both genders. A comparison of observed TLC data with values predicted by Neder equations showed significant lower values by the present data. Mean values were similar between data from present study and those derived by Crapo. Conclusion: New predicted values for lung volumes were obtained in a sample of white Brazilians. The values differ from those derived by Neder, but are similar to those derived by Crapo.

RESUMO Objetivo: Derivar valores de referência para brasileiros adultos brancos saudáveis que nunca fumaram e comparar os valores obtidos com os valores de referência derivados por Crapo e por Neder. Métodos: Equações de referência por regressões quantílicas foram derivadas em 122 homens e 122 mulheres, não obesos, em sete cidades do Brasil. A idade variou entre 21 e 92 anos nas mulheres e de 25 a 88 anos nos homens. Os volumes pulmonares foram medidos por pletismógrafo de corpo automatizados SensorMedics, de acordo com as recomendações da SBPT e ATS/ERS. Os limites inferior e superior, expressos pelo percentil 5 e 95, foram derivados por equações específicas. Os resultados foram comparados aos sugeridos por Crapo em 1982 e Neder em 1999. Resultados: Os valores medianos para a capacidade pulmonar total (CPT) foram influenciados apenas pela estatura nos homens, e pela estatura e idade nas mulheres. O volume residual foi influenciado pela idade e estatura em ambos os sexos. O peso se correlacionou diretamente com a capacidade inspiratória e inversamente com a capacidade residual funcional e com o volume de reserva expiratório em ambos os sexos. A CPT observada, comparada com os valores previstos pela equação de Neder, foi significativamente menor. Os valores médios foram semelhantes entre os dados do presente estudo e os de Crapo. Conclusões: Novos valores previstos para os volumes pulmonares foram obtidos em uma amostra de brasileiros de raça branca. Os valores diferem daqueles derivados por Neder, mas são semelhantes aos derivados por Crapo.

The clinical research progress of surgical pleth index / 中国医师杂志

With the promotion of the concept of " precise anesthesia",it is important to achieve both the anesthetic effect and the avoidance of a series of side effects caused by overdose of anesthetic drugs in anesthesia management.How to determine the optimal dose of anesthetic drugs and maintain the appropriate depth of anesthesia has become a problem that anesthesiologists must focus on and urgently needs solving.First of all,maintaining adequate depth of anesthesia requires adequate sedation and analgesia.At present,there are many clinical monitoring methods for the depth of anesthesia (sedation and analgesia).Several tools,including bispectral index and entropy index,which have been proved to reflect the depth of sedation well,but they are not sensitive to noxious stimuli such as pain during surgery.This article reviews a recently developed method for monitoring surgical pleth index (SPI),and describes the research background,research principles,relevant influencing factors,and research progress in detail.

Comparison of pulse pressure variation and pleth variability index in the prone position in pediatric patients under 2 years old / 대한마취과학회지

BACKGROUND: The assessment of intravascular volume status is very important especially in children during anesthesia. Pulse pressure variation (PPV) and pleth variability index (PVI) are well known parameters for assessing intravascular volume status and fluid responsiveness. We compared PPV and PVI for children aged less than two years who underwent surgery in the prone position. METHODS: A total of 27 children were enrolled. We measured PPV and PVI at the same limb during surgery before and after changing the patients’ position from supine to prone. We then compared PPV and PVI at each period using Bland-Altman plot for bias between the two parameters and for any correlation. We also examined the difference between before and after the position change for each parameter, along with peak inspiratory pressure, heart rate and mean blood pressure. RESULTS: The bias between PPV and PVI was −2.2% with a 95% limits of agreement of −18.8% to 14.5%, not showing significant correlation at any period. Both PPV and PVI showed no significant difference before and after the position change. CONCLUSIONS: No significant correlation between PVI and PPV was observed in children undergoing surgery in the prone position. Further studies relating PVI, PPV, and fluid responsiveness via adequate cardiac output estimation in children aged less than 2 years are required.

Dynamic changes of lung function in mice with pulmonary fibrosis / 医学研究生学报

Objective　Pulmonary function testing is a commonly used indicator for clinical evaluation of the degree of pulmonary fibrosis in patients. This paper aims to investigate the dynamic changes of lung function in mice with pulmonary fibrosis and to establish a range of reference values for lung function parameters in normal Kunming mice.　Methods　Twenty-eight SPF Kunming mice were randomly divided into normal control group (n=14) and model group (n=14). After anesthesia with 10% chloral hydrate, the normal control group only underwent tracheal puncture. The model group received intratracheal puncture and injection of bleomycin (BLM) (5 mg/kg body weight), and the lung function indicators of all mice were detected in the same order on the 1st, 2nd, 3rd and 4th weekends after modeling: Ti, Te, PIF, PEF, TV, EV, RT, MV, f, Penh and EF50.　Results　After intratracheal BLM injection, mice in the model group showed decreased hair softness and smoothness, hair loss and decreased activity after the 2nd week. Compared with the control group, Ti, Te and RT values in the model group significantly increased at week 4 (P<0.05), while the values of PEF, RT, MV, f and EF50 decreased significantly at the same week (P<0.05). Compared with the model group at week 1, the differences in Ti, Te, RT and f values at week 2, 3 and 4 were statistically significant (P<0.05); the differences in MV and EF50 values at week 3 and 4 were statistically significant (P<0.05); while the PIF values only showed differences at week 4 (P<0.001). Compared with the Penh values in the control group at week 2, 3 and 4 (0.553±0.189, 0.662±0.164, 0.712±0.189), the differences of the model group (0.820±0.205, 0.936±0.188, 1.053±0.236) showed statistical significance (P<0.001). Compared with the model group at week 1, the differences of Penh values in the model group only showed statistical significance at week 3 and 4 (P<0.05). Through four-week lung function test, various parameters were obtained, among which the normal range of the main index Penh value was 0.27-0.88.　Conclusion　The lung function detected by the non-invasive whole body plethysmography system was stable and reliable with good effects; the lung function in mice with the BLM-induced pulmonary fibrosis continued to decrease within four weeks. Penh, which reflects airway resistance, can be used for overall screening of the lung function among the test mice after two weeks of modeling.

Functional residual capacity in healthy infants aged 1-24 months using the baby body plethysmography (Carefusion TM)

BACKGROUND@#The only lung volume that can be measured reliably in infants is the functional residual capacity (FRC). Published reference values vary, thus, there is a need to determine values for healthy infants using the available equipment.@*OBJECTIVES@#To determine the normal values of FRC in healthy infants using the baby body plethysmogram (CareFusion) and to determine the correlation between FRC and weight, length, age, and gender.@*METHODS@#FRC was measured using the CareFusion MasterScreen baby body plethysmogram in 62 healthy infants aged 1-24 months old. FRC was measured after sedation with Chloral hydrate at 50 mg/kg body weight. Three measurements were performed from which the mean (SD) FRC was calculated. To depict the change in FRC with growth, regression analysis between FRC as dependent variable and weight, length, and age as independent variables was done.@*CONCLUSION@#The FRC values obtained in this study is 24.56 ml/kg (4.41). There is a direct correlation of FRC with age, weight, and length. The result of this study was comparable to other studies and may be used as a reference value for healthy infants.