Investigation of the Effect of Voiding Position on Uroflometric Parameters and Voiding Residue in Healthy Volunteers in Imam Reza Hospital, Mashhad, Iran

Background & Aims: Uroflowmetry is a common procedure to examine the lower urinary tract system. Uroflowmetry results are affected by different factors. In this study, the effect of voiding position on uroflowmetric parameters and voiding residue were investigated in healthy subjects. Methods: This descriptive–analysis study was performed on 41 healthy volunteers with mean age of 33.22 ± 9.45 referred to Imam Reza Hospital, Mashhad, Iran, in 2011. Nonprobability purposive sampling method was used in this study. The uroflowmetric tests were performed in the standing, sitting, and crouching positions for men and in the sitting and crouching positions for women. Post voiding residue (PVR) was measured using transabdominal ultrasound after voiding. Maximum flow rate (Qmax), average flow rate (Qave), voiding volume (VV), voiding time (VT) and PVR values were compared between voiding positions. SPSS software, paired t-test, and repeated measurement were used for data analysis. All P values less than 0.05 were considered as significant. Results: The differences between Qmax (P = 0.193 for men and P = 0.792 for women), Qave (P = 0.312 for men and P = 0.896 for women), and VV (P = 0.187 for men and P = 0.124 for women), and VT (P = 0.017) in different positions were not statistically significant. However, the lowest and highest mean post voiding residue in men (P = 0.001) were in the crouching and standing positions, respectively. Inwomen, mean post voiding residue (P = 0.039) was lower in crouching position than sitting position. Conclusion: In healthy subjects, voiding position does not affect Qmax, Qave, and VT. However it seems PVR was lower in the position they usually used.