Can recording only the day-time voided volumes predict bladder capacity?

Area of Science:

• Pediatric Urology
• Bladder Function Assessment

Background:

• Assessing bladder capacity is crucial for diagnosing and managing pediatric lower urinary tract dysfunction.
• Traditional methods like the first morning void (FMV) can be unreliable in children with nocturnal enuresis.

Purpose of the Study:

• To establish an easy method for assessing bladder capacity using daytime voided volumes.
• To validate the estimation of maximal voided volume (MVV) using daytime measurements in healthy children.

Main Methods:

• Evaluated 177 healthy children using frequency-volume charts (FVC) over 48 hours.
• Measured daytime voided volumes and compared them to the first morning void (FMV).

Main Results:

• Daytime voided volumes typically ranged from 30% to 80% of the maximal voided volume (MVV).
• Maximal voided volume during daytime (MVVDT) was significantly lower than MVV (179.5±71.1 mL vs. 227.0±79.2 mL).
• A strong correlation (r=0.801) was found between MVV and estimated MVV using MVVDT x 1.25.

Conclusions:

• Estimating bladder capacity using MVVDT x 1.25 provides a reliable alternative when FMV is unavailable.
• This method is particularly useful for patients with nocturnal enuresis, improving bladder capacity assessment.