Uroflowmetric analysis and derivation of nomograms for normal paediatric Indian population between 5 to 15 years of age

Asian J Urol. 2022 Apr;9(2):125-131. doi: 10.1016/j.ajur.2021.08.001. Epub 2021 Aug 8.

Abstract

Objective: We aimed to established normal uroflowmetric values and subsequently derived nomograms of maximum flow rate (Qmax) and average flow rate (Qavg) against voided volume (VV) in children aged 5-15 years at our institute.

Methods: A total of 440 children underwent uroflowmetric evaluation with no history of urological, renal, psychiatric, or neurological disorder between 5 and 15 years of age. Each subject data regarding Qmax, Qavg, VV, time to Qmax, and flow time, as well as age, sex, height, and weight were recorded. Of the 440 children, around 300 (68.18%) children could produce a normal flow rate at VV of more than 50 mL. Of the remaining 140 (31.82%) children, 50.00% voided less than 50 mL, and remaining 50.00% had abnormal voiding pattern, staccato or interrupted (21.43% each) and plateau or tower shaped (3.57% each). Cases were divided into two age groups (5-9 years and 10-15 years), and uroflowmetric analysis was done between boys and girls in both age groups to derive nomograms of Qavg and Qmax.

Results: Qmax and Qavg flow nomograms were plotted for boys and girls. Mean Qmax for boys was 16.68 mL/s and for girls 20.69 mL/s. The mean Qavg values were 11.04 mL/s and 8.60 mL/s for girls and boys, respectively. The Qmax and Qavg values were higher in girls. There were significant increases in flow rates with increasing age, body surface area, and VV in both sexes.

Conclusions: Nomograms for Qmax and Qavg may be a useful tool in evaluation of lower urinary tract disturbances in children.

Keywords: Flow rate; Nomograms; Pediatric; Uroflowmetry; Voided volume.