Introdução: A instabilidade postural é uma manifestação tardia da doença de Parkinson (DP), sendo incapacitante e um fator de risco para quedas. O comprometimento das respostas posturais na DP é provavelmente a causa mais importante das quedas. Estas respostas posturais dependem de informações vestibulares, somatossensoriais e visuais, que são integradas nos núcleos da base, tronco cerebral e medula espinhal. Este estudo avalia um possível papel do sistema vestibular na fisiopatologia da instabilidade postural através da vertical visual subjetiva (VVS). A VVS avalia o julgamento da vertical gravitacional e é um teste sensível da função otolítica. Objetivo: Analisar a VVS em pacientes com DP e comparar com os controles normais; correlacionar a direção das inclinações da VVS e o lado de maior comprometimento da doença; correlacionar a VVS com as escalas Unified Parkinsons Disease Rating Scale (UPDRS), Hoehn e Yahr (HY); determinar se as inclinações da VVS estão relacionadas à instabilidade postural. Métodos: Pacientes com DP foram submetidos a: exame neurológico completo; escalas UPDRS e HY; teste clínico para avaliação da instabilidade postural e o teste da VVS foi realizado em 45 pacientes e 45 controles normais. Resultados: As inclinações da VVS nos controles tiveram valores entre -2,7º a +2,4º, média +0,18º e DP = 1.17, e entre -6,4º a +5,6º, média -0,50º e DP = 2.89 nos pacientes. Não houve diferença das médias entre pacientes e controles, porém os pacientes tiveram variabilidade maior. A avaliação da variabilidade no grupo dos pacientes utilizou os valores absolutos de cada medida da VVS. As médias dos valores absolutos da VVS nos controles e pacientes foram 1,55º e 3,65º, respectivamente, sendo maiores nos pacientes (p<0,0001). Houve uma fraca correlação positiva entre os resultados da VVS a avaliação motora da escala UPDRS; razoável correlação positiva com a escala HY e uma boa correlação entre a VVS e a severidade da instabilidade postural. Conclusões: Os erros do julgamento da VVS foram significantemente maiores em pacientes comparados aos controles. Além disso, houve uma fraca correlação com as escalas UPDRS e Hoehn e Yahr, e boa correlação da VVS com a instabilidade postural. Estes resultados sugerem que as vias aferentes do sistema vestibular estão comprometidas nos pacientes com DP e poderiam estar envolvidas nos mecanismos que levam à instabilidade postural, indicando que a instabilidade postural não é um fenômeno exclusivamente motor / Introduction: Postural instability is a late manifestation of Parkinsons disease (PD). The impairment of postural responses on PD is probably the most important cause of falls. These postural responses depend on vestibular, somatossensorial and visual inputs, and they are integrated on basal ganglia, brainstem and spinal cord. By use of the subjective visual vertical (SVV), this study evaluates a possible role of the vestibular system on the hysiopathology of postural instability. The SVV makes the judgment of gravitational vertical and is a specific test of otolith function. Objective: To analyze the SVV in patients with PD and to compare with normal controls; to correlate the direction of SVV-inclinations with the side of more impairment disease; to correlate the SVV with the Unified Parkinsons Disease Rating Scale (UPDRS), the Hoehn and Yahr (HY) scales, to determine if the inclination of SVV is related to the postural instability. Methods: Patients with idiopathic PD were submitted to: complete neurological examination; the scales UPDRS and HY; the clinical test to postural instability and the SVV test. The measurement of SVV was performed in 45 patients and 45 normal controls. Results: The SVV-inclination ranged from -2.7º to +2.4º, mean 0.18º and SD = 1.17 in controls, and from -6.4º to +5.6º, mean -0.50º and SD = 2.89 in patients. There was no difference in mean between patients and controls, but patients had a greater deviation. The variability evaluation in patients group used absolute values of SVV. The means of absolute values of SVV in controls and patients were 1.55º and 3.65º, respectively, and were greater in patients (p < 0.0001). There was a weak correlation between SSV and scores in the motor evaluation of UPDRS scale. A reasonable correlation was found between SVV values and scores in the HY scale. There was a good correlation between SVV and severity of postural instability. Conclusions: The error of judgment of SVV was significantly increased in the patients compared to controls. Further, there was a weak correlation with UPDRS and HY scales, and a good correlation of SVV with postural instability. These results suggest that the afferent pathways of vestibular system are impaired in patients with PD and could be involved in mechanisms underlying postural instability; so that, postural instability is not only a motor phenomemon

Introdução: O uso de biomassa como combustível para aquecimento e preparação de alimentos vem sendo considerado como um importante fator associado à prevalência aumentada de sintomas respiratórios e à perda de função pulmonar. No presente estudo apresentamos os efeitos respiratórios da exposição crônica à combustão de biomassa (BM) dentro (BMD) ou fora (BMF) do domicílio em uma população do interior do Brasil e comparamos os resultados aos de indivíduos da mesma população que utilizam gás liquefeito de petróleo (GLP). Métodos: Foram incluídos 1402 indivíduos em 260 domicílios divididos em três grupos de acordo com a exposição (GLP, BMD, BMF). Os sintomas respiratórios foram avaliados utilizando questionários validados. O índice de refletância de filtros de papel foi utilizado para avaliar a exposição à biomassa. Em 48 domicílios a concentração de material particulado PM2,5 também foi quantificada. Provas de função pulmonar (PFP) foram realizadas em 120 indivíduos. Resultados: O índice de refletância correlacionou-se diretamente com a concentração de PM2,5 (r=0,92, p<0,001) e foi portanto utilizado para estimar a exposição (ePM2,5). Demonstramos aumento significativo do ePM2,5 no grupo BMD e BMF em comparação com o grupo GLP (p<0,001). Houve ainda aumento significativo da razão de chances (OR) para tosse produtiva, chiado e dispnéia nos adultos expostos à BMD (OR=2,93, 2,33, 2,59, respectivamente) e BMF (OR=1,78, 1,78, 1,80, respectivamente) em comparação com o grupo GLP. As PFP demonstraram que tanto o grupo BM-nãotabagista como GLP-tabagista apresentaram redução no % do VEF1 predito e na relação VEF1/CVF quando comparado com GLP-não-tabagista (p=0,002), o mesmo ocorrendo para o grupo BM-tabagista, em relação a todos os demais (p<0,05). A prevalência de obstrução de vias aéreas encontrada no grupo BM-não-tabagista e GLP-tabagista foi semelhante (20%) e menor do que a observada no grupo BM-tabagista (33%). A PFP correlacionou-se inversamente com o tempo de exposição e a concentração de ePM2,5 (p<0,001). Conclusões: A exposição crônica à combustão de biomassa está associada com o aumento da prevalência de sintomas respiratórios, redução da função pulmonar e desenvolvimento de doença pulmonar obstrutiva crônica. Esses efeitos estão associados com a duração e magnitude da exposição e são potencializadas pelo tabagismo. / Introduction: The use of biomass fuels for cooking and heating is considered an important factor associated with respiratory symptoms and loss of pulmonary function. We report the respiratory effects of chronic exposure to biomass (BM) combustion in a Brazilian population and compared the results with those of individuals from the same community using Liquefied Petroleum Gas (LPG). Methods: 1,402 individuals in 260 residences were divided into three groups according to exposure (LPG, indoor-BM, outside-BM). Respiratory symptoms were assessed using questionnaires. Reflectance of paper filters was used to assess BM. In 48 residences the amount of PM2.5 was also quantified. Pulmonary function tests (PFT) were performed in 120 individuals. Results: Reflectance-index correlated directly with PM2.5 (r=0.92, p<0.001) and was used to estimate exposure (ePM2.5). There was a significant increase in ePM2.5 in Indoor-BM and Outside-BM, compared to LPG (p<0.001). There was a significantly increased odds ratio (OR) for cough with sputum, sneezing and dyspnea in adults exposed to Indoor-BM (OR=2.93, 2.33, 2.59, respectively) and Outside-BM (OR=1.78, 1.78, 1.80, respectively) compared to LPG. PFTs revealed both non-smoker-BM and smoker-LPG individuals to have decreased %predicted-FEV1 and FEV1/FVC as compared to non-smoker-LPG (p=0.022). Reduction was also observed in both parameters between smoker-BM and other groups (p<0.05). The prevalence of chronic obstructive pulmonary disease was 20% for both non-smoker-BM and smoker-LPG and smaller than that observed for smoker-BM (33%). PFT data was inversely correlated with duration and ePM2.5 (p<0.001). The prevalence of airway obstruction was 20% in both non-smoker-BM and smoker-LPG subjects. Conclusions: Chronic exposure to BM is associated with increased prevalence of respiratory symptoms, reduced lung function and development of chronic obstructive pulmonary disease. These effects are associated with the duration and magnitude of exposure and are exacerbated by tobacco smoke.

O presente trabalho teve por finalidade estudar as alterações do sistema circulatório provocadas pela cirurgia cardíaca sob circulação extracorpórea, 12 pacientes adultos, anestesiados e curarizados, selecionados aleatoriamente, sendo 6 deles valvopatas e 6 coronariopatas. As alterações respiratórias foram verificadas por medidas da mecânica respiratória e da ventilação-oxigenação pulmonar. Do ponto de vista mecânico, o sistema respiratório foi analisado como um todo e individualizando os seus componentes - pulmões e parede torácica, tanto do ponto de vista elástico como também fluxo-resistivo. A análise das propriedades resistivas do sistema respiratório foi feita através de um método que se utiliza da insuflação pulmonar com fluxo constante, seguida de uma oclusão súbita das vias aéreas. Esta análise permite que tanto para o sistema respiratório como também para os pulmões e parede torácica, obtenha-se o valor resistivo máximo (Rmax) bem como o valor mínimo da resistência (Rmin) ao lado das resistências geradas pelas desigualdades do sistema (Ru). Este estudo foi feito graças a estimativa das diferentes respostas de frequência de cada um destes componentes. As medidas de ventilação-oxigenação foram aferidas pelo cálculo do \"shunt\" pulmonar (Qs/Q) e gradiente alvéolo-arterial de oxigenio P(A-a)O2. Tanto as medidas mecânicas como as de ventilação-oxigenação foram feitas na vigência de uma fração inspirada de O2 de 100% e realizadas de 15 a 30 minutos após a entubação traqueal, sendo repetidas logo após o fechamento do tórax. [...] / The aim of this work was to study the respiratory alterations caused by cardiac surgery under cardiopulmonary bypass in 12 randomly selected anesthetized paralyzed adult patients; 6 with acquired valvar disease and 6 with ischmic cardiopathy. Respiratory alterations were assessed by respiratory mechanics and lung ventilation-oxygenation measurements. Respiratory mechanics analyzed the respiratory system as a whole and partitioned into its components: lung and chest wall, measuring both the elastic and resistive properties were measured using a constant inflation flow followed bu a sudden occlusion. This analysis provides the maximum resistance value (Rmax), the minimum resistance value (Rmin), and the resistance caused by the uneven distribution of mechanical properties within the system (Ru), for respiratory system, lung and chest wall. This analysis is based on the frequency dependence differences of each component of respiratory system. The ventilation-oxygenation evaluation was done by the calculation of pulmonary shunt and the alveolar arterial oxygen gradient (P (A-a)O2). Both mechanical and ventilation-oxygenation measurement were done with a oxygen inspired fraction of 1 and performed 15 to 30 minutes after tracheal intubation and repeated just after thorax closure. [...]

Vestibular evoked myogenic potentials (VEMP) are short latency electromyograms (EMG) evoked by high-level acoustic stimuli and recorded from surface electrodes over the tonically contracted sternocleidomastoid (SCM) muscle and are presumed to originate in the saccule. The present experiments examined the effects of click and tone-burst level and stimulus frequency on the latency, amplitude, and threshold of the VEMP in subjects with normal hearing sensitivity and no history of vestibular disease. VEMPs were recorded in all subjects using 100 dB nHL click stimuli. Most subjects had VEMPs present at 500, 750, and 1000 Hz, and few subjects had VEMPs present at 2000 Hz. The response amplitude of the VEMP increased with click and tone-burst level, whereas VEMP latency was not influenced by the stimulus level. The largest tone-burst-evoked VEMPs and lowest thresholds were obtained at 500 and 750 Hz. VEMP latency was independent of stimulus frequency when tone-burst duration was held constant.

Vestibular-evoked myogenic potentials (VEMPs) are proposed as a reliable test to supplement the current vestibular test battery by providing diagnostic information about saccular and/or inferior vestibular nerve function. VEMPs are short-latency electromyograms (EMGs) evoked by high-level acoustic stimuli and recorded from surface electrodes over the tonically contracted sternocleidomastoid muscle. VEMP amplitude is influenced by the EMG level, which must be controlled. This study examined the ability of subjects to achieve the EMG target levels over a range of target levels typically used during VEMP recordings. In addition, the influence of target EMG level on the latency and amplitude of the click- and tone-evoked VEMP was examined. The VEMP amplitude increased as a function of EMG target level, and the latency remained constant. EMG target levels ranging from 30 microV to 50 microV are suggested for clinical application of the VEMP.

<p>Deep breathing exercises are widely used in the postoperative care to prevent or reduce pulmonary complications, but no scientific evidence for the efficacy has been found after coronary artery bypass grafting (CABG) surgery. </p><p>The aim of the thesis was to describe postoperative pulmonary function and to evaluate the efficacy of deep breathing exercises performed with or without a blow bottle device for positive expiratory pressure (PEP) 10 cmH₂O or an inspiratory resistance-positive expiratory pressure (IR-PEP) mask with an inspiratory pressure of -5 cmH₂O and an expiratory pressure of +10 to +15 cmH₂O. </p><p>Patients undergoing CABG were instructed to perform 30 slow deep breaths hourly during daytime for the first four postoperative days. Patient management was similar in the groups, except for the different breathing techniques. </p><p>Measurements were performed preoperatively, on the fourth postoperative day and four months after surgery. The immediate effect of the deep breathing exercises was examined on the second postoperative day. Pulmonary function was assessed by spirometry, diffusion capacity for carbon monoxide and arterial blood gases. Atelectasis was determined by chest roentgenograms or spiral computed tomography (CT). </p><p>Lung volumes were markedly reduced on the fourth postoperative day. Four months after surgery the pulmonary function was still significantly reduced. On the second and fourth postoperative day all patients had atelectasis visible on CT. A single session of deep breathing exercises performed with or without a mechanical device caused a significant reduction in atelectasis and an improvement in oxygenation. No major differences between deep breathing performed with or without a blow bottle or IR-PEP-device were found, except for a lesser decrease in total lung capacity in the blow bottle group on the fourth postoperative day. Patients who performed deep breathing exercises after CABG had significantly smaller atelectasis and better pulmonary function on the fourth postoperative day compared to a control group who performed no exercises.</p>

Deep breathing exercises are widely used in the postoperative care to prevent or reduce pulmonary complications, but no scientific evidence for the efficacy has been found after coronary artery bypass grafting (CABG) surgery. The aim of the thesis was to describe postoperative pulmonary function and to evaluate the efficacy of deep breathing exercises performed with or without a blow bottle device for positive expiratory pressure (PEP) 10 cmH2O or an inspiratory resistance-positive expiratory pressure (IR-PEP) mask with an inspiratory pressure of -5 cmH2O and an expiratory pressure of +10 to +15 cmH2O. Patients undergoing CABG were instructed to perform 30 slow deep breaths hourly during daytime for the first four postoperative days. Patient management was similar in the groups, except for the different breathing techniques. Measurements were performed preoperatively, on the fourth postoperative day and four months after surgery. The immediate effect of the deep breathing exercises was examined on the second postoperative day. Pulmonary function was assessed by spirometry, diffusion capacity for carbon monoxide and arterial blood gases. Atelectasis was determined by chest roentgenograms or spiral computed tomography (CT). Lung volumes were markedly reduced on the fourth postoperative day. Four months after surgery the pulmonary function was still significantly reduced. On the second and fourth postoperative day all patients had atelectasis visible on CT. A single session of deep breathing exercises performed with or without a mechanical device caused a significant reduction in atelectasis and an improvement in oxygenation. No major differences between deep breathing performed with or without a blow bottle or IR-PEP-device were found, except for a lesser decrease in total lung capacity in the blow bottle group on the fourth postoperative day. Patients who performed deep breathing exercises after CABG had significantly smaller atelectasis and better pulmonary function on the fourth postoperative day compared to a control group who performed no exercises.

Thesis (MSc. (Human Physiology, Faculty of Health Sciences))--University of Pretoria, 2008. / Summary in English. Includes bibliographical references.

The overall aim of the research described in this thesis was to evaluate the effect of vitamin A supplementation on respiratory health, assessed by lung function in children aged 6--9 years. It comprises three studies. / The first study determined the magnitude of vitamin A deficiency in the target population in Wukro wereda, Northern Ethiopia. Of the 1339 eligible children identified by house to house surveys, 824 had complete data for vitamin A indicators and anthropometry. Xerophthalmia was detected in 5.8% of the children, 8.4% had serum retinol levels <0.35 mumol/L and 51.1% between 0.35--0.70 mumol/L. Liver vitamin A reserve was also found to be low in 41.0% of the children using the Modified Relative Dose Response (MRDR) and in about 85% of the children, the daily vitamin A intake was below the FAO/WHO basal requirement (<250 RE/day). / The second study found that in comparison with children with adequate vitamin A reserve (MRDR < 0.06), those with low reserve (MRDR &ge; 0.06) had forced expiratory volume in one second (FEV1) 48.8 ml (p = 0.006) lower when unadjusted, 23.1 ml (p = 0.04) when partially adjusted for age, gender and height and 14.1 ml (p = 0.20) when fully adjusted for demographic, general health, lung function and household related characteristics. / The third study describes the results of a randomized controlled trial (RCT) to evaluate the impact of vitamin A supplementation on respiratory health as assessed by change in FEV1 at 4 months. The average change was 53.3 ml (n = 496) and 53.8 ml (n = 501) in the vitamin A and placebo groups respectively. After adjusting for baseline covariates, the difference between them was -3.6 ml (95%CI: -21.6, 14.4). In sub-analysis of the data, gender and vitamin A status subcategories were found to be effect modifiers. / In conclusion, high dose vitamin A supplementation did not show an effect on change in FEV1 at 4 months in children aged 6--9 years with high prevalence of vitamin A deficiency. Sub-analysis findings suggest that the benefits to vitamin A intervention in the study setting can probably be achieved if the other nutritional deficiencies such as zinc are addressed. Moreover, the results also suggest that the effects of vitamin A supplementation on respiratory health status are complex and these need to be taken into account in future studies to assess the clinical and public health implications of vitamin A supplementation in this age group.

Diss. (sammanfattning) Stockholm : Karolinska institutet, 2005. / Härtill 5 uppsatser.