Is a post-void residual volume of 17 mL after consuming 750 mL of fluid a concern?

Assessment of Post-Void Residual Volume of 17 mL After Consuming 750 mL of Fluid

A post-void residual (PVR) volume of 17 mL after consuming 750 mL of fluid is completely normal and not a concern. This represents excellent bladder emptying and is well below any threshold that would indicate bladder dysfunction.

Understanding Normal Post-Void Residual Volumes

• Normal PVR volume should be less than 50 mL in healthy individuals 1
• A PVR volume of 17 mL represents only about 2.3% of the consumed fluid volume (750 mL), which is well below concerning thresholds
• For context, even the 90th percentile PVR for adolescents is around 20-35 mL depending on age and gender 2

Clinical Significance of Low PVR Values

• Low PVR volumes like 17 mL indicate:
  • Proper bladder contractility
  • Absence of outlet obstruction
  • Effective coordination between bladder contraction and urethral relaxation
  • Normal voiding function

When PVR Becomes Concerning

• PVR volumes become concerning at much higher levels:
  • PVR >100-200 mL warrants caution before certain treatments like botulinum toxin therapy 1
  • PVR >180 mL in adult men is associated with increased risk of bacteriuria 3
  • PVR >350 mL may indicate significant bladder dysfunction 1

Measurement Considerations

• PVR measurements show significant intra-individual variability and should be repeated if abnormalities are suspected 1
• The timing between voiding and PVR measurement should be short to ensure accuracy 4
• Ultrasound bladder volume measurement is preferred to urethral catheterization for PVR assessment 4

Conclusion

The PVR volume of 17 mL after consuming 750 mL of fluid represents excellent bladder emptying efficiency. This is well within normal limits and indicates healthy lower urinary tract function. No further evaluation or intervention is needed based on this finding alone.