Baseline abdominal pressure and valsalva leak point pressures-correlation with clinical and urodynamic data.

Aims: To characterize the factors contributing to changes in baseline abdominal pressure (P(abd)) and the correlation between DeltaVLPP, VLPP(tot), and other clinical and urodynamic variables.

Methods: Two hundred sixty-four female patients who had undergone an anti-incontinence procedure between February 1994 and October 1999 were retrospectively reviewed. The urodynamics performed for each patient included abdominal and vesical pressures measured in a standardized manner with the patient sitting upright and the pressure sensors maintained at the level of the symphysis pubis. VLPP was determined at bladder volumes of 200 mL during a gradually increasing Valsalva maneuver.

Results: Baseline P(abd) varied between 10 and 55 cm H(2)O (mean, 32.7 +/- 8.8) and were significantly correlated with patient weight (P<0.001) and with patient body mass index (P<0.001). Baseline P(abd) was not found to be correlated with patient age, Baden and Walker Classification of the grading of pelvic floor prolapse, degree of incontinence (determined by the number of pads used per day), or prior surgical procedures for stress incontinence. Higher baseline P(abd) were significantly correlated with the peak abdominal pressure reached during the Valsalva maneuver (P<0.0001) and with VLPP(tot) (P<0.0001) but not with DeltaVLPP. Higher VLPP(tot) significantly correlated with decreased age (P=0.004), less severe incontinence (P=0.004), higher peak Valsalva pressure (P<0.0001), and the ability to increase abdominal pressure for a longer period of time (time to peak P(abd) during Valsalva). VLPP(tot) and DeltaVLPP had similar statistical correlation with all the clinical variables examined and neither could predict the outcome of any anti-incontinence surgery. By using a VLPP of 60 cm H(2)O as a cutoff to differentiate severe ISD from GSUI, 211 (67.4%) of the patients would be categorized as having ISD according to their DeltaVLPP compared with only 106 (40.1%) by using the VLPP(tot).

Conclusions: Baseline P(abd) varies considerably among patients, is correlated with patient weight and habitus. In addition, it varies with both the ability to be increased for longer periods of time and with VLPP(tot). Looking at VLPP(tot) and DeltaVLPP will result in a different categorization of the type of incontinence in at least 25% of patients and, thus, affect the physician's selection of an anti-incontinence procedure for an individual patient.