Volumetric capnography versus spirometry for the evaluation of pulmonary function in cystic fibrosis and allergic asthma.

OBJECTIVE: To compare the values of the markers for volumetric capnography and spirometry and their ability to classify children and adolescents with asthma, cystic fibrosis (CF), and healthy controls. METHODS: This was a cross-sectional study that included 103 patients with controlled persistent allergic asthma, 53 with CF and a healthy control group with 40 volunteers (aged 6 to 15 years), of both sexes. The individuals underwent volumetric capnography and spirometry. RESULTS: Phase III slope (SIII), SIII standardized by exhaled tidal volume (SIII/TV) and capnographic index (SIII/SII)×100 (KPIv) were different among the three groups assessed, with highest values for CF. The relation between the forced expiratory volume in one second and the forced vital capacity (FEV1/FVC) was the only spirometric marker that presented difference on the three groups. On individuals with normal spirometry, KPIv and FEV1/FVC were different among the three groups. The ROC curve identified the individuals with asthma or CF from the control group, both through volumetric capnography (better to identify CF in relation to the control using KPIv) and through spirometry (better to identify asthma in relation to the control). KPIv was the best parameter to distinguish asthma from CF, even in individuals with normal spirometry. CONCLUSION: Volumetric capnography and spirometry identified different alterations in lung function on asthma, CF, and healthy controls, allowing the three groups to be distinguished.

Safety, Tolerability, and Effects of Sodium Bicarbonate Inhalation in Cystic Fibrosis.

BACKGROUND: Among the many consequences of loss of CFTR protein function, a significant reduction of the secretion of bicarbonate (HCO3-) in cystic fibrosis (CF) is a major pathogenic feature. Loss of HCO3- leads to abnormally low pH and impaired mucus clearance in airways and other exocrine organs, which suggests that NaHCO3 inhalation may be a low-cost, easily accessible therapy for CF. OBJECTIVE: To evaluate the safety, tolerability, and effects of inhaled aerosols of NaHCO3 solutions (4.2% and 8.4%). METHODS: An experimental, prospective, open-label, pilot, clinical study was conducted with 12 CF volunteer participants over 18 years of age with bronchiectasis and pulmonary functions classified as mildly to severely depressed. Sputum rheology, pH, and microbiology were examined as well as spirometry, exercise performance, quality-of-life assessments, dyspnea, blood count, and venous blood gas levels. RESULTS: Sputum pH increased immediately after inhalation of NaHCO3 at each clinical visit and was inversely correlated with rheology when all parameters were evaluated: [G' (elasticity of the mucus) = - 0.241; G″ (viscosity of the mucus) = - 0.287; G* (viscoelasticity of the mucus) = - 0.275]. G* and G' were slightly correlated with peak flow, forced expiratory volume in 1 s (FEV1), and quality of life; G″ was correlated with quality of life; sputum pH was correlated with oxygen consumption (VO2) and vitality score in quality of life. No changes were observed in blood count, venous blood gas, respiratory rate, heart rate, peripheral oxygen saturation of hemoglobin (SpO2), body temperature, or incidence of dyspnea. No adverse events associated with the study were observed. CONCLUSION: Nebulized NaHCO3 inhalation appears to be a safe and well tolerated potential therapeutic agent in the management of CF. Nebulized NaHCO3 inhalation temporarily elevates airway liquid pH and reduces sputum viscosity and viscoelasticity.

Evaluation of continuous constant current and continuous pulsed current in sweat induction for cystic fibrosis diagnosis.

BACKGROUND: The sweat test (ST) is the gold standard for the diagnosis of cystic fibrosis (CF). However, little is known about sweat induction using different types of currents and waves. In this context, our objective was to develop a device to induce sweat and compare the use of continuous constant current (CCC) and continuous pulsed current (CPC) in individuals with CF and healthy controls. METHODS: A prospective cross-sectional study with experimental intervention. The variables of gender, ethnicity, age, and body mass index (BMI) were considered. The method of Gibson and Cooke was used, and the following markers were evaluated: sweat weight, electrical impedance, sufficient sweat amount, and CF diagnosis. Triangular (TPC) or sinusoidal (SPC) pulsed current was applied to the right arm, and CCC was applied to the left arm. RESULTS: The study analyzed 260 individuals, 141/213 (54.2%) were female participants, 135/260 (51.9%) were Caucasians. The distribution of individuals by concentration of chloride at the ST was: (CF) 26/260 (10%); (borderlines) 109/260 (41.9%); (healthy) 97/260 (37.3%); (insufficient weight in sweat) 28/260 (10.8%). No association was observed between the sufficient sweat amount to perform the ST when we compared the currents. However, the SPC showed a higher amount of sweat weight. Using Bland and Altman plot considering the agreement between the sweat chloride values achieved from CPC [SPC and TPC] and CCC, there was no proportional bias and mean values are unrelated and only explain less than 8% of the variation. Moreover, TPC presented higher electrical impedance when compared with SPC and CCC. SPC presented lower electrical impedance and higher sweat weight than CCC. Male participants presented lower electrical impedance and higher sweat weight with CCC and TPC, and higher sweat weight with SPC. CONCLUSIONS: The evaluated currents are safe and able to induce and produce sweat in sufficient quantities for the ST. SPC presented lower electrical impedance when compared with other currents. The use of SPC is recommended to induce sweat in patients with sweat problems. Finally, ethnicity, gender, age and BMI did not influence sweat induction at the ST, and no side effect was observed in our study.

Instrumentos objetivos tradicionais de avaliação respiratória em respiradores orais / Traditional instruments objectives of respiratory evaluation in mouth breathers

A obstrução nasal é uma das principais anormalidades que afetam a permeabilidade nasal (PN) e em consequência está associada à respiração oral. Considerando a importância das complicações respiratórias e sua relação com o mecanismo de obstrução nasal, ressalta-se a necessidade e importância desse tipo de avaliação na população pediátrica e adulta. Objetivo: apresentar uma atualização da literatura quanto aos instrumentos objetivos para avaliação da permeabilidade das vias aéreas superiores e sua aplicabilidade na avaliação respiratória de indivíduos RO. Síntese dos dados: a revisão bibliográfica foi realizada utilizando as palavras-chaves: mouth breathing, nasal obstruction, nasal patency evaluation e instrumentos objetivos tradicionais da permeabilidade das vias aéreas: rhinomanometry, sniff nasal inspiratory pressure nasal peak flow, acoustic rhinometry, rhinomanometry e nasal spirometry. Uma síntese dos trabalhos foi organizada apresentando os instrumentos objetivos mais tradicionais encontrados na literatura. Com base nos estudos selecionados, discutiu-se sobre a indicação destes recursos na avaliação da permeabilidade de vias aéreas superiores. Conclusões: a avaliação respiratória objetiva de RO pode ser realizada por diferentes instrumentos tradicionais, utilizados tanto na avaliação, diagnóstico e identificação de efeitos de intervenções de RO.

Influence of thoracic spine postural disorders on cardiorespiratory parameters in children and adolescents with cystic fibrosis.

OBJECTIVES: To assess the impact of increased thoracic kyphosis on pulmonary function and functional capacity in children and adolescents with cystic fibrosis (CF) and to verify the influence of disease severity, age and nutritional status on this deformity. METHOD: This was a cross-sectional, analytical study conducted at a university hospital. It included CF patients with confirmed diagnosis and without pulmonary exacerbation. The sample was submitted to postural assessment, spirometry (FEV1, FVC and FEV1/FVC) and 6-minute walk test distance (6-MWT distance). Data were analyzed using the Mann Whitney test, Spearman correlation and logistic regression. RESULTS: Forty-two patients were enrolled, 61.9% presented increase of thoracic kyphosis. There was no difference in values of FEV1, FVC, FEV1/FVC and 6-MWT distance between the groups with or without thoracic kyphosis (p = 0.407; p = 0.756; p = 0.415; p = 0.294). In the group without alteration, patients with more disease severity had a mean FEV1 of 74.1±21.9% and FVC of 79.8±18.7% while in those of lesser severity higher values were found (95.6±12.2% and 97.6±13.2%, respectively) (p = 0.027 and p = 0.027). The presence of kyphosis was correlated with age (p = 0.048) but not with severity (p = 0.151) and body mass index (p = 0.088). CONCLUSIONS: There was a high prevalence of increased thoracic kyphosis in children and adolescents with CF. The deformity did not affect pulmonary function and functional capacity and there was no relationship with disease severity. Regardless of posture, worsening of disease severity determined worsening of pulmonary function.

Influência da alteração postural da coluna torácica em parâmetros cardiorrespiratórios de crianças e adolescentes com fibrose cística / Influence of thoracic spine postural disorders on cardiorespiratory parameters in children and adolescents with cystic fibrosis

OBJETIVOS: Avaliar a repercussão do aumento da cifose torácica na função pulmonar e na capacidade funcional de crianças e adolescentes com fibrose cística e verificar a influência da gravidade da doença, idade e aspectos nutricionais sobre essa deformidade. MÉTODO: Estudo analítico de corte transversal, realizado em um hospital universitário. Incluiu fibrocísticos com diagnóstico confirmado e fora de exacerbação pulmonar. A amostra foi submetida à avaliação postural, registro de parâmetros espirométricos - volume expiratório forçado no primeiro segundo (VEF1), capacidade vital forçada (CVF) e VEF1/CVF - e da distância percorrida pelo teste de caminhada de 6 minutos. Para análise dos dados, utilizou-se teste de Mann-Whitney, correlação de Spearman e regressão logística, considerando-se nível de significância de 5%. RESULTADOS: No total, 42 pacientes foram incluídos, e 61,9% apresentaram aumento da cifose torácica. Não houve diferença nos valores de VEF1, CVF, VEF1/CVF e distância percorrida pelo teste de caminhada de 6 minutos entre os grupos com e sem cifose torácica (p = 0,407; p = 0,756; p = 0,415; p = 0,294). No grupo sem alteração postural, fibrocísticos mais graves apresentaram média de VEF1 de 74,1±21,9% e CVF de 79,8±18,7%, enquanto naqueles de menor gravidade foram verificados valores superiores (95,6±12,2% e 97,6±13,2%, respectivamente) (p = 0,027 e p = 0,027). A presença de cifose correlacionou-se com a idade (p = 0,048), mas não com a gravidade (p = 0,151) e o índice de massa corporal (p = 0,088). CONCLUSÕES: Observou-se uma alta prevalência de aumento da cifose torácica em crianças e adolescentes com fibrose cística. Essa deformidade não alterou a função pulmonar e a capacidade funcional e não teve relação com a gravidade da doença. Independentemente da postura, a piora da gravidade da doença determinou piora da função pulmonar.

OBJECTIVES: To assess the impact of increased thoracic kyphosis on pulmonary function and functional capacity in children and adolescents with cystic fibrosis (CF) and to verify the influence of disease severity, age and nutritional status on this deformity. METHOD: This was a cross-sectional, analytical study conducted at a university hospital. It included CF patients with confirmed diagnosis and without pulmonary exacerbation. The sample was submitted to postural assessment, spirometry (FEV1, FVC and FEV1/FVC) and 6-minute walk test distance (6-MWT distance). Data were analyzed using the Mann Whitney test, Spearman correlation and logistic regression. RESULTS: Forty-two patients were enrolled, 61.9% presented increase of thoracic kyphosis. There was no difference in values of FEV1, FVC, FEV1/FVC and 6-MWT distance between the groups with or without thoracic kyphosis (p = 0.407; p = 0.756; p = 0.415; p = 0.294). In the group without alteration, patients with more disease severity had a mean FEV1 of 74.1±21.9% and FVC of 79.8±18.7% while in those of lesser severity higher values were found (95.6±12.2% and 97.6±13.2%, respectively) (p = 0.027 and p = 0.027). The presence of kyphosis was correlated with age (p = 0.048) but not with severity (p = 0.151) and body mass index (p = 0.088). CONCLUSIONS: There was a high prevalence of increased thoracic kyphosis in children and adolescents with CF. The deformity did not affect pulmonary function and functional capacity and there was no relationship with disease severity. Regardless of posture, worsening of disease severity determined worsening of pulmonary function.

Exercise capacity, respiratory mechanics and posture in mouth breathers / Capacidade ao exercício, mecânica respiratória e postura em respiradores bucais

Chronic and persistent mouth or oral breathing (OB) has been associated with postural changes. Although posture changes in OB causes decreased respiratory muscle strength, reduced chest expansion and impaired pulmonary ventilation with consequences in the exercise capacity, few studies have verified all these assumptions. OBJECTIVE: To evaluate exercise tolerance, respiratory muscle strength and body posture in oral breathing (OB) compared with nasal breathing (NB) children. MATERIAL AND METHOD: A cross-sectional contemporary cohort study that included OB and NB children aged 8-11 years old. Children with obesity, asthma, chronic respiratory diseases, neurological and orthopedic disorders, and cardiac conditions were excluded. All participants underwent a postural assessment, maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP), the six-minute walk test (6MWT), and otorhinolaryngologic evaluation. RESULTS: There were 107 children (45 OB and 62 NB). There was an association between abnormal cervical posture and breathing pattern: 36 (80.0 percent) OB and 30 (48.4 percent) NB presented abnormal head posture (OR=4.27 [95 percent CI: 1.63-11,42], p<0.001). The mean MIP and MEP were lower in OB (p=0.003 and p=0.004). CONCLUSION: OB children had cervical spine postural changes and decreased respiratory muscle strength compared with NB.

A respiração bucal ou oral (RO) crônica e persistente tem sido associada a alterações posturais. Embora alterações de postura, na RO, causem diminuição da força muscular respiratória, menor expansibilidade torácica, prejuízo na ventilação pulmonar com consequências na capacidade de exercício, poucos estudos têm comprovado todas estas situações. OBJETIVO: Avaliar a tolerância ao exercício, a força muscular respiratória e a postura corporal em crianças respiradoras orais (RO), comparadas com respiradoras nasais (RN). MATERIAL E MÉTODO: Estudo de coorte contemporânea com corte transversal, no qual foram incluídas crianças RO e RN de 8 a 11 anos. Foram excluídas crianças obesas, asmáticas, com doenças respiratórias crônicas, distúrbios neurológicos, ortopédicos e cardiopatas. Todos os participantes foram submetidos à avaliação postural, pressão inspiratória máxima (PImáx), pressão expiratória máxima (PEmáx), teste de caminhada de seis minutos (TC6) e avaliação otorrinolaringológica. RESULTADOS: Participaram 107 crianças (45 RO e 62 RN). Houve associação entre alteração da postura cervical e padrão respiratório: 36(80,0 por cento) RO e 30(48,4 por cento) RN apresentaram alteração da postura da cabeça, respectivamente (RCP=4,27[IC95 por cento:1,63 - 11,42], p<0,001). Médias de PImáx e PEmáx foram menores nos RO (p=0,003 e p=0,004). CONCLUSÃO: Crianças RO apresentaram alteração postural da coluna cervical e diminuição da força muscular respiratória quando comparados com RN.

Respiração bucal e anteriorização da cabeça: efeitos na biomecânica respiratória e na capacidade de exercício em crianças / Mouth breathing and forward head posture: effects on respiratory biomechanics and exercise capacity in children

OBJETIVO: Avaliar a tolerância ao exercício submáximo e a força muscular respiratória em relação à anteriorização da cabeça (AC) e ao tipo respiratório em crianças com respiração bucal (RB) ou nasal (RN). MÉTODOS: Estudo analítico transversal com um grupo controle no qual foram incluídas crianças de 8 a 12 anos com diagnóstico clínico otorrinolaringológico de RB, recrutadas do Ambulatório do Respirador Bucal do Hospital de Clínicas da Universidade Estadual de Campinas, Campinas (SP), entre outubro de 2010 e janeiro de 2011. Os critérios de exclusão foram obesidade, asma, doenças respiratórias crônicas, cardiopatias e distúrbios neurológicos ou ortopédicos. Todos os participantes foram submetidos a avaliação postural, teste de caminhada de seis minutos (TC6) e determinação de PImáx e PEmáx. RESULTADOS: Das 92 crianças do estudo, 30 tinham RB e 62 tinham RN. No grupo RB, não houve diferenças nas médias de PImáx, PEmáx e distância percorrida pelo TC6 (DTC6) entre o grupo com AC classificada como grave ou moderada e aquele com AC normal (p = 0,622; p = 0,957; e p = 0,079, respectivamente). No grupo RN, as médias de PImáx e PEmáx foram maiores no grupo com AC moderada do que naquele com AC normal (p = 0,003 e p = 0,004, respectivamente). Os valores de PImáx, PEmáx e DTC6 foram menores no grupo RB do que no grupo RN. A presença de AC moderada determinou maiores valores de PImáx e PEmáx. CONCLUSÕES: A RB afetou negativamente a biomecânica respiratória e a capacidade de exercício. A presença de AC moderada atuou como um mecanismo de compensação para uma melhor função da musculatura respiratória.

OBJECTIVE: To evaluate submaximal exercise tolerance and respiratory muscle strength in relation to forward head posture (FHP) and respiratory mode in children, comparing mouth-breathing (MB) children with nasal-breathing (NB) children. METHODS: This was a controlled, analytical cross-sectional study involving children in the 8-12 year age bracket with a clinical otorhinolaryngology diagnosis of MB, recruited between October of 2010 and January of 2011 from the Mouth Breather Clinic at the State University of Campinas Hospital de Clínicas, located in the city of Campinas, Brazil. The exclusion criteria were obesity, asthma, chronic respiratory diseases, heart disease, and neurological or orthopedic disorders. All of the participants underwent postural assessment and the six-minute walk test (6MWT), together with determination of MIP and MEP. RESULTS: Of the 92 children in the study, 30 presented with MB and 62 presented with NB. In the MB group, the differences between those with moderate or severe FHP and those with normal head posture, in terms of the mean MIP, MEP and six-minute walk distance (6MWD), were not significant (p = 0.079, p = 0.622, and p = 0.957, respectively). In the NB group, the mean values of MIP and MEP were higher in the children with moderate FHP than in those with normal head posture (p = 0.003 and p = 0.004, respectively). The mean MIP, MEP, and 6MWD were lower in the MB group than in the NB group. Values of MIP and MEP were highest in the children with moderate FHP. CONCLUSIONS: Respiratory biomechanics and exercise capacity were negatively affected by MB. The presence of moderate FHP acted as a compensatory mechanism in order to improve respiratory muscle function.