Continuous and stepwise cystometry through suprapubic catheters—effect of infusion pattern and infusion rate on the cystometrogram of the normal human bladder

Continuous cystometry at two filling rates (50 and 100 ml min-1) and stepwise cystometry (successive rapid volume infusions followed by bladder wall relaxation) were performed in 12 healthy subjects. Suprapubic catheters were used for infusion and recording of perivesical and intravesical pressures. The continuous cystometrograms obtained at filling rates of 50 and 100 ml min-1, respectively, did not differ with respect to desire to void, transmural pressure increase or bladder capacity. Stepwise cystometry allowed the bladders to be filled to a slightly larger volume than during continuous cystometry, but with comparatively lower transmural pressures only at very large distension of the bladder. There was considerable inter-individual variation in transmural pressure at both continuous and stepwise cystometry. Stepwise cystometry did not appear to provide any important additional information about pressure-volume relationship in the normal human bladder than could be obtained at routine clinical cystometry.