No primary role of ambulatory urodynamics for the management of spinal cord injury patients compared to conventional urodynamics

Abstract

Adequate urodynamic assessment of bladder behavior is essential in spinal cord injury (SCI) patients. Ambulatory urodynamics are more sensitive to detect detrusor overactivity (DO) than conventional urodynamics. The primary objective of this study was to determine the value of ambulatory urodynamics for the diagnosis of DO in SCI patients compared to conventional urodynamics. Twenty-seven SCI patients who were suspected of DO underwent both conventional and ambulatory urodynamics at one day. A single involuntary detrusor contraction (IDC) was defined as a detrusor pressure rise of at least 10 cmH(2)O. DO according to the ICS definition was used in addition to minimize the influence of catheter artifacts. Outcome of urodynamics was used for decisions on treatment. Ambulatory urodynamics were more sensitive to diagnose IDC and DO. Conventional urodynamics had a sensitivity of 82% and specificity of 75% for DO diagnosis compared to ambulatory urodynamics. Mean maximum detrusor pressures did not differ significantly between both urodynamics. When the maximum detrusor pressure at conventional urodynamics did not exceed 40 cmH(2)O, 83% (10/12) of patients had a mean maximum detrusor pressure under 40 cmH(2)O at ambulatory urodynamics. Although the inter-individual DO diagnostic agreement was lower for ambulatory than conventional urodynamics (58%, K = 0.201 vs. 77%, K = 0552), the treatment agreement was higher for ambulatory urodynamics (58% vs. 42%). Ambulatory urodynamics do not seem necessary for diagnosis and risk assessment in SCI patients suspected for DO when conventional urodynamics are done properly. The exact role of urodynamics in treatment decision remains to be determined.