Classificação dos valores perineométricos: uma proposta de escala

Abstract

Introduction: Pelvic floor muscles (PFM) correspond to a group of skeletal muscles that are located at the basis of the pelvic cavity. These muscles are activated in different situations in wich there is an increase in intra-abdominal pressure. Its integrity and good functioning are fundamental in maintaining urinary and fecal continence and in sustaining the pelvic organs. There are several PFM evaluation techniques supported by the literature, such as the perineometry. Perineometers are aimed to measure pressure changes in the vagina in response to voluntary contraction of PFM. Perineometry equipments are simple, minimally invasive and inexpensive. Althought it is an objective measure of the degree of pressure performed by the PFM voluntary contraction, perineometry does not have rating ranges that guide the interpretation of its results. Objective: To develop a classification scale for perineometry. Methodology: A cross-sectional observational study. The sample was the result of a non-probalistc type sampling process. Women were recruted on spontaneous demand. A perineometric evaluation and the manual strength test of the PFM were performed by means of the bidigital touch, and the force was categorized by the Oxford Modified Scale. The collected data were tabulated and analyzed in the program IMB Statistical Package for the Social Sciences version 20.0. To determine the classification ranges of perineometry, a simple linear regression was performed, using as an explanatory variable the Oxford Modified Scale and as a response variable the arithmetic mean of the three measurements of perineometry. The linear regression was performed in the statistical program R version 3.2.4. Results: The 259 women included in the analysis had a mean age of 52.80 (± 8.78) years. Perineometry presented an average of 35.1 ± 22.7 (CI: 32.1 - 38.0) cmH2O. The median PFM strength level was 3 (Q25: 2; Q75: 3). There was a strong, positive and statistically significant correlation between the degree of strength by the Oxford Modified Scale and perineometry (r = 0.846, p <0.01). The stratification of the perineometric measurements was performed on a five-point scale, ranging from very weak pressure to strong pressure. According to the proposed scale, values between 7.5 and 14.5 cmH2O correspond to a very weak pressure; The range of 14.6 to 26.5 cmH2O is equivalent to a weak pressure; A moderate pressure is in the range of 26.6 to 41.5 cmH2O; Values of 41.6 to 60.5 cmH2O represent a good pressure and values above 60.6 is a strong pressure. Conclusion: Perineometric values were stratified on a five-point scale. By observing the results, from this scale it is possible to establish the ranges of pressure exerted by the voluntary contraction of the PFM. The achieved result in this work has implications in clinical practice, since it will guide the specialists and the patients about the degree of muscular strength. For the literature, is promoted for the first time the presentation of a scale of perineometry classification standards.