Abdominal leakage point pressure (ALPP) including Valsalva leakage point pressure (VLPP) is one of the most crucial examination to detect stress urinary incontinence (SUI). However, there is no agreed standard way of performing ALPP. This study is aimed to compare the way of VLPP using syringe to the way without syringe by asking to increase their abdominal (intravesical) pressure in women with SUI. We investigated whether Valsalva leakage was associated with the crude straining pressure and the external – sphincter electromyography (e-EMG) amplitude.

42 women were recruited who underwent urodynamic study including VLPP while external - sphincter electromyography (e-EMG) was recorded with surface electrode for their lower urinary tract symptom (mean age: 66.4±15.1 years old). UDS were performed in standardized and reproducible manner, according to Good Urodynamic Practice (Catheter size was 6Fr, infusion speed was 50mL/min) For each patient, both the way of VLPP using syringe and without syringe were examined respectively: The way of VLPP using syringe was performed by blowing into syringe at the bladder volume of maximum desire to void during UDS each patient, and Valsalva maneuver without syringe was asking to increase their abdominal (intravesical) pressure themselves. VLPP is defined as the abdominal (intravesical) pressure at which urinary leakage occur with increased abdominal pressure in absence of detrusor contraction. We described the presence of urinary leakage and the crude straining pressure, the external – sphincter electromyography amplitude using surface electrode.

Crude straining pressure (above zero) 92.7±33.1 cmH2O using syringe was higher than 58.2 ± 21.7 cmH2O without syringe (p<0.0000025). Along with this, 10 patients (38.5%) using syringe and 4 patients (15.4%) without syringe leaked respectively (no statistical significance). Between those who leaked and who did not leak, crude straining pressure (above zero) was not different. EMG amplitude was not different between both groups. Between those who leaked and who did not leak, e-EMG amplitude was not different, either.

This study showed that the crude straining pressure using syringe was significantly higher than without syringe (p<0.00000025), the detection rate of the Valsalva leakage using syringe was also higher and more than twice times in patients with a complaint of urinary incontinence. In terms of the external-sphincter EMG during Valsalva maneuver, there was no significant change. It is essential that we detect not only VLPP value but also the presence of urinary leakage to diagnose SUI.

This study showed that the crude straining pressure using syringe was significantly higher than without syringe, and the detection rate of the Valsalva leakage using syringe was also higher while external-sphincter EMG was not clearly change. The Valsalva leakage was seemed to associated with VLPP value and may be due to the external-sphincter EMG. These result suggested that the way of VLPP using syringe might more beneficial to grasp urodynamic SUI.

Warren K, Abram P. Leak point pressure: how useful are they?.Curr Opin Urol. 2015 Jul;25(4):317-22