Voiding dysfunction after radical retropubic prostatectomy: more than external urethral sphincter deficiency.

OBJECTIVES

To analyse the relationship between RRP and urodynamic bladder dysfunction, and compare preoperative and postoperative functional status over long-term follow-up. Hypothesis on the pathophysiologic mechanism underlying urodynamic dysfunction has been reported.

METHODS

PubMed databank search for original articles followed by review of urodynamic parameters: bladder filling sensation, detrusor overactivity, bladder compliance, cystometric bladder capacity, impaired detrusor contractility, bladder outlet obstruction, urinary incontinence.

RESULTS

Detrusor dysfunction was rarely present as the sole diagnosis and was usually coupled with intrinsic sphincter deficiency. Data on bladder filling sensation, cystometric capacity, detrusor overactivity, impaired detrusor contractility, and bladder outlet obstruction were limited and contradictory. Detrusor overactivity was a de novo dysfunction in 2%-77% of patients. Impaired bladder compliance was present in 8%-39% of patients and was de novo in about 50%. Impaired detrusor contractility was found in 29%-61% of patients, was de novo in 47%, and recovered in about 50% of patients. The role of these dysfunctions as etiologic agents of urinary incontinence or voiding symptoms was unevenly assessed.

CONCLUSIONS

Postoperative decentralization of the bladder, inflammation and/or infection, and geometric bladder wall alteration associated with preexisting hypoxemia with/without neuroplasticity have been posited as causes of detrusor dysfunction. Nevertheless, the lack of consistent preoperative urodynamic investigation makes it difficult to assess the operation's exact role in causing these dysfunctions. Thus, urodynamics performed, at least in selected cases, preoperatively and during follow-up could help arrive at a precise diagnosis of the underlying dysfunction, indicate the appropriate treatment, and prevent the incidence and onset of postoperative urinary incontinence.