From the Guidelines
Post-void residual (PVR) urine volume is the amount of urine that remains in the bladder after a person has finished urinating, typically measured by catheterization or ultrasound scan, with normal values usually less than 50 mL, though values up to 100 mL may be acceptable in some adults. This measurement is crucial in evaluating patients with urinary symptoms such as frequency, urgency, or incontinence, as higher volumes can indicate problems with bladder emptying due to conditions like urinary obstruction, neurogenic bladder, or detrusor muscle weakness 1.
Importance of PVR Measurement
PVR measurement is an important diagnostic tool that helps identify patients at an increased risk of acute urinary retention (AUR) and allows for the monitoring of treatment outcomes 1. The procedure is simple and can be performed non-invasively using transabdominal ultrasonography, which is recommended for its safety and accuracy 1.
Interpretation of PVR Values
While there is no universally agreed-upon definition of an elevated PVR, values above 100 mL may indicate significant urinary retention and require further investigation 1. Elevated PVR values can lead to complications like urinary tract infections or kidney damage if left untreated, emphasizing the need for regular monitoring to assess the effectiveness of treatments for bladder dysfunction and guide management decisions 1.
Clinical Application
In clinical practice, PVR measurement should be considered as part of the initial diagnostic assessment and during subsequent monitoring as a safety parameter, especially in patients with lower urinary tract symptoms (LUTS) 1. The marked intra-individual variability of residual urine volume necessitates repeating the test to improve precision, particularly if the initial result is borderline or if there are concerns about bladder emptying 1.
Conclusion is not allowed, so the answer just ends here.
From the Research
Definition of Post-Void Residual Urine Volume
- Post-void residual (PVR) urine volume refers to the amount of urine that remains in the bladder after urination 2, 3, 4, 5, 6.
- It is an important parameter in assessing urinary function and can be used to diagnose and monitor various urinary tract conditions.
Measurement of Post-Void Residual Urine Volume
- PVR volume can be measured using various methods, including catheterization and ultrasound bladder scanning 2, 4, 6.
- The accuracy of PVR measurement can vary depending on the method used, with ultrasound bladder scanning being a non-invasive and relatively accurate method 6.
Clinical Significance of Post-Void Residual Urine Volume
- A high PVR volume can indicate urinary retention, which can increase the risk of urinary tract infections, hydronephrosis, and other complications 2, 3, 4.
- The definition of a significant PVR volume is unclear, but a value of 180 ml or greater has been suggested as a cutoff point for increased risk of bacteriuria 4.
- PVR volume can also be used to assess bladder voiding efficiency and diagnose conditions such as underactive bladder 5.