Correlation of Xiphopubic Distance, Body Weight, Height and Body Mass Index with Intravesical and Abdominal Initial Resting Pressures in Urodynamic Testing in the Sitting Position.

Objectives: To compare the initial resting intravesical pressure (p ) and abdominal pressure (p ) in the sitting position with the typical range of values, to assess the correlation between such pressures and patient xipho-pubic distance, body weight, height and body mass index (BMI), and to estimate if xipho-pubic distance can be a guide to interpret initial resting pressures in urodynamic testing.

Methods: Women with lower urinary tract symptomatology referred for urodynamic testing were consecutively enrolled in a prospective study. Conventional cystometry was done following "good urodynamic practices". The correlation between initial resting p and p and xipho-pubic distance, body weight, height and BMI were studied using simple and multiple linear regression analysis. Statistical significance was defined as P < 0.05.

Results: One hundred women aged (mean ± SD) 59.2 ± 13.3 were studied. There was a significant correlation between both p and p , and xipho-pubic distance, body weight and BMI and no correlation with height. Over the multiple analysis, xipho-pubic distance and body weight correlated independently with p ; body weight correlated independently with p . Three patients had p and/or p out of typical range, with BMIs values of 18.48, 18.72 and 35.81 kg/m . There was a wide range of difference between xipho-pubic distance and initial resting pressures.

Conclusions: Out of range initial resting pressures occur in underweight (or close to) or severely obese patients. Xipho-pubic distance and body weight correlated independently with p . Body weight correlated independently with p . Xipho-pubic distance cannot be a guide to interpret the initial resting pressures.