Urodynamic monitoring during percutaneous sacral nerve neurostimulation inpatients with neurogenic detrusor hyperreflexia

The purpose of this study was to assess urodynamics parameter changes induc ed by acute sacral neurostimulation (SNS) in spinal cord injury (SCI) patie nts with neurogenic detrusor hyperreflexia. Fourteen SCI patients with urge incontinence owing to a hyperreflexive bladder were prospectively evaluate d. Neurostimulation was performed on the root that obtained the best motor response (10 Hz, 210 mu seconds) and amplitude ranges of >0 to 10 V. The ur odynamics study was done in the prone position. Four cystometries were reco rded before (two), during (one), and 10 minutes after stimulation (one). Ma ximal bladder capacity (MBC) (volume to first leakage), bladder volume at f irst uninhibited contraction (BV1StC). and maximal detrusor pressure during uninhibited contractions (P(det)max) were compared. Left S3 foramen was th e most commonly used (9/14). Mean amplitude of stimulation was 4.5 V (range , 0.5-8.5 V). Statistically significant differences (Mann-Whitney U-test) w ere found for MBC, BV1stC. and P(det)max with mean variations of +206.8 mL (+107%, P < 0.001), +151.5 mL (+98%, P < 0.01), and -23.4 cm H2O (-27%, P < 0.05), respectively. Patient gender and SCI level did not reveal any diffe rence. Patients who reached a MBC of up to 400 mL (+278.2 mL, +129%, n = 10 ) with SNS had statistically significant improvement of BV1stC (+210.2 mL, +125%, P < 0.01) and P(det)max (-33.3 cm H2O, -38%, P < 0.01). Acute tempor ary SNS in SCI patients has a profound effect on key urodynamics parameters . These neurologically impaired patients with detrusor hyperreflexia may be appropriate candidates for implantable SNS. Neurourol. Urodynam. 20:61-71, 2001. (C) 2001 Wiley-Liss. Inc.