Symptoms versus Flow Rates versus Urodynamics in the Selection of Patients for Prostatectomy

Abstract

Many prostatectomies are performed on the basis of symptoms alone; 39% of patients referred by their family doctors and 23% of patients who were on waiting lists for prostatectomy of other hospitals, but who had not undergone any urodynamic investigations, were found to be unobstructed on urodynamic criteria. A screening peak urinary flow rate of 12 ml/s or less was associated with urodynamic evidence of obstruction in 95% of cases; 35% of patients with symptoms of outflow obstruction and a flow rate greater than 12 ml/s were also found to be obstructed. One year post-operatively, 84% of patients who were selected for surgery on combined symptomatic and urodynamic criteria were pleased symptomatically with their result. The failure of detrusor instability to resolve following prostatectomy was associated with symptomatic failure of treatment. Residual obstruction was demonstrated in 5 patients who had undergone prostatectomy and were asymptomatic at this time. This study illustrates that objective measures are necessary in the assessment of patients prior to prostatectomy in order to select only patients who are obstructed. The importance of a screening flow rate is emphasised. All patients who underwent surgery had cystometric evidence of obstruction but the symptomatic results of surgery were no better than the results in patients who had been assessed according to non-urodynamic selection criteria. We have thus failed to identify a need for routine cystometry in the pre-operative assessment of these patients. Cystometry does, however, have a role in assessing patients with pre-operative flow rates greater than 12 ml/s and in those who remain symptomatic following prostatectomy.

Comparison of parameters to determine the cause of urinary disturbance in men with prostate volume less than 20 milliliters

“…19 Additionally, McLoughlin et al concluded that a Q max of less than 12 mL/s is a good indicator of outflow obstruction. 20 In the present study, the positive predictive value of Q max for outflow obstruction was 65% at a flow rate of less than 10 mL/s and 100% at a flow rate of less than 5 mL/s. These values were lower than those reported by other researchers.…”

Uroflowmetry in a Large Population of Brazilian Men Submitted to a health check up program and its correlation with ipss and prostate size

“…Although symptoms usually stimulate patients to seek treatment, some studies have shown that there is no correlation between symptoms and bladder outlet obstruction (10,11). Uroflowmetry can be an additional tool for urologists before surgical intervention or treatment failure.…”

Effects of Short-Term Treatment with the α(1)-Blocker Alfuzosin on Urodynamic Pressure/Flow Parameters in Patients with Benign Prostatic Hyperplasia

“…It is well recognized that symptoms are often not reliably associated with outflow obstruction and a poor urinary stream may result from impaired detrusor contractility instead of obstruction, or a normal flow rate could be sustained by a supranormal detrusor pressure. Furthermore, symptom score and peak urinary flow rate are often not in agreement [13][14][15].…”