| dc.description.abstract | In the respiratory system, the respiratory muscle strength (RMS) is reflected by the pressure developed by these muscles which controls the ventilation. In classic maneuvers assessment of the RMS individuals generate maximum inspiratory and expiratory pressures (respectively, MIP and MEP) against an occluded mouthpiece generating the maximal static respiratory pressures (PRM). The sniff nasal inspiratory pressure (SNIP) is a dynamic maneuver assessment of maximal inspiratory muscle strength. Describe the RMS through measures valid and interpret them correctly is essential for the diagnosis of respiratory muscle weakness and monitoring of physiotherapy interventions. However, there is a remarkable variability between the reference values proposed for the PRM, due to individual factors and / or methodological inherent in each study, making its applicability questionable. In order to overcome this variability the American Thoracic Society and Eu ropean Respiratory Society (ATS/ERS) and the Brazilian Society of Thoracic Association (SBPT) recommend methodological standardization. The general objective of this thesis was to describe the respiratory muscle strength in a sampl e of adults from Belo Horizonte/MG with aged between 20 to 89 years following the methodological recommendations of the ATS/ERS and SBPT, including the description of reference values and prediction equations. To achieve this objective we have developed the four studies that comprise this thesis. The first study aimed to evaluate the specific methodological quality and to summarize the studies that have established reference values for MIP in adults from performing a systematic review and meta -analysis. We verified a low methodological quality and a remarkable heterogeneity between MIP values in the six studies that were included in the meta -analysis, confirming the variability of the reference values reported in the literature. The meta -analysis provided references values, created from the broader and representative ethnic group, which can be extrapolated to the general population because of the statistical method used. The objectives of the second study was to determine the number of maneuvers required for the individual to reach peak performance during the PRM measures and compare the pressure values selected from the employment of the protocols proposed by the ATS/ERS, SBPT, and the protocol proposed in this thesis. The results of this study suggest the need for a greater number of maneuvers to reach the criterion of reproducibility proposed by this thesis in relation to other criteria evaluated, and that using the proposed criteria resulted in achieving higher pressure values for PRM reaffirming thus, the effect of learning tests RMS. The third study was to evaluate the psychometric properties (test -retest reliability and concurrent validity) of PRM and SNIP obtained through the manometer developed by the Núcleo de Estudos e Pesquisa em Engenharia Biomédica (NEPEB) in partnership with the Laboratório de Avaliação e Pesquisa em Desempenho Cardiorrespiratório (LabCare) UFMG. The results of this study demonstrated that the assessment of RMS in healthy subjects with manovacuometer UFMG values were adequate test-retest reliability and concurrent validity. The fourth study in this thesis aimed to propose predictive equations, average values and lower limits of predicted normal data variations due to sex and age for the PRM and the SNIP, following recommendations made by the ATS/ERS and SBPT in a sample of adult population of Belo Horizonte/MG whit aged between 20 to 89 years. The mean values were observed, and predicted limits inferior PRM and SNIP according to age and sex and were proposed predictive equations for measures of RMS. All volunteers had normal lung function, absence of cognitive deficit (volunteers over 60 years), body mass index than non-featured malnutrition or obesity. Rega rding the predictive power of the equations of FMR, the MIP model, the combination of sex, age and weight resulted in a coefficient of determination (r2) of 34% [MIP = 63.27 - 0.55 (age) + 17 , 96 (sex) + 0.58 (weight)], the model of MEP, age and age 2, sex, waist circumference in an r2 of 49% [MEP = - 61.41 + 2.29 (age) - 0, 03 (age 2) + 33.72 (sex) + 1.40 (waist)] and the model of SNIP, age, waist circumference and physical fitness in an r 2 of 21% [SNIP = 46.44 - 0.52 (age ) + 0.86 (waist) - 10.51 (physical fitness)]. It was noted in this study explained that the physical less than 50% variation in RMS. The measure of FMR obtained by volitional tests is influenced by the biological variables, inherent to each individual, leading to instability of the measure s verified by high coefficients of variation within the same age and sex. Methodological aspects concerning the test also are responsible for the diversity of values references reported, highlighting the learning effect of the measure. In order to circumvent the factors influencing the extent of RMS recommended greater control of biological variables that can directly influence these measures and compliance with the methodological recommendations recommended by current guidelines for testing of respirator y muscles. | |
