4-HOUR VOIDING OBSERVATION IN HEALTHY INFANTS

Purpose: We present the 4-hour voiding observation as a method for bas ic assessment of bladder function in infants and nontoilet trained chi ldren. Materials and Methods: Voiding pattern, including number of voi dings, voided volume, bladder capacity and residual urine for 4 hours, was determined noninvasively in 43 healthy infants. Results: The infa nts voided an average of 1 time per hour but with great variability. B ladder capacity increased with age according to the formula, 38 + 2.5 x age (months). Mean residual urine plus or minus standard deviation w as 4.6 +/- 3.0 ml. In all infants residual volume was less than 5 ml. at least once during observation. Conclusions: The 4-hour voiding obse rvation is an easy noninvasive method of characterizing the voiding pa ttern, focusing especially on emptying difficulties, in infants and no ntoilet trained children.