Repeated pressure‐flow studies in the evaluation of bladder outlet obstruction due to benign prostatic enlargement

Abstract

Test-retest reliability of repeated voids in pressure-flow studies and the influence on maximum flow rate (Q max pQ), detrusor pressure at maximum flow rate (p det Q max ), voided volume, and residual urine were studied. Also the agreement in interpretation of pressureflow tracings between investigators and a single blinded central reader acting as a quality control center (QCC) were assessed. In addition, correlations between p det Q max and patient age, International Prostate Symptom Score (IPSS), free maximum flow rate (Q max ), and prostate volume were calculated. Using suprapubic pressure recording, 216 men with lower urinary tract symptoms (LUTS) due to benign prostatic enlargement (BPE) were investigated in 11 centers. In each pressure-flow study, three sequential voids were performed, and quality controlled recordings were analyzed for Q max pQ and p det Q max by the QCC. PROD #1031rectal ultrasound was used to measure the prostate volume. Mean Q max pQ did not change, but p det Q max decreased significantly in the second and third sequential voids. Using the Abrams-Griffiths nomogram definition of obstruction, 125 patients (67%) were classified as obstructed from the first void, but only 111 patients (59%) from the third void. The agreement between the investigator assessment and that of a single blinded reader was good.There was no significant correlation between p det Q max and patient age, IPSS, and Q max , whereas a modest correlation was found between p det Q max and prostate volume. In summary, there was no significant change in Q max pQ, but p det Q max decreased for the three consecutive voids, which can be explained by a decrease in outlet resistance. The agreement between the investigator and QCC interpretations shows the value of a standardized technique, supporting the feasibility of multicenter urodynamic studies. There is a modest, but statistically significant, correlation between detrusor pressure and prostate size, supporting the hypothesis that prostate size is a contributing factor in symptomatic BPH. Neurourol.

Lower urinary tract symptoms, prostate volume, uroflowmetry, residual urine volume and bladder wall thickness in Turkish men: a comparative analysis

“…Severe complications during or after urodynamic investigation were reported in up to 19%, including urinary retention, gross hematuria, urinary tract infection, and fever [10]. Also there are studies in the literature that reported no association between invasive pressure flow parameters and the IPSS [11][12][13]. According to guidelines pressure flow studies are optional diagnostic tests for routine work-up of elderly men with LUTS [14][15].…”

Pentosan polysulfate decreases prostate smooth muscle proliferation and extracellular matrix turnover

“…12 The symptomatic response to finasteride has been shown to be greater in prostates weighing more than 40 g. 13 However, the effect of finasteride on prostatic symptoms may be mediated by other factors than mere reduction in volume. The mechanism of action of phytoestrogens remains unclear, but at least one randomized double-blinded study reported nearly equal improvements in uroflow, symptom scores, and quality of life when compared to 5-alphareductase inhibitors.…”

>Normal Ranges of Variability for Urodynamic Studies of Neurogenic Bladders in Spinal Cord Injury

“…Most of the studies were performed on patients without SCI. The largest trial was a prospective, multicenter trial including 216 men with lower tract symptoms caused by benign prostatic hypertrophy (7). The study evaluated the test-retest reliability of several urodynamic parameters during 3 voids and found no significant changes in various parameters, including maximum flow rate, volume voided, and residual volume.…”

“…There are several studies that support both shortterm and long-term reproducibility of urodynamic studies (7)(8)(9)(10)(11). However, there have been no studies specifically evaluating and documenting the variability of urodynamic tests.…”