Effects of acute bolus and chronic continuous intrathecal baclofen on genitourinary dysfunction due to spinal cord pathology.

A prospective, blinded study was done to examine the effects of acute bolus and chronic continuous intrathecal baclofen on genitourinary function in 10 patients with severe spasticity due to spinal cord pathology. Genitourinary function was assessed by symptom questionnaires and urodynamic studies performed after a bolus dose of baclofen and 6 to 12 months after continuous intrathecal baclofen. Results were compared to placebo for acute bolus testing or to pre-continuous intrathecal baclofen values. In all patients with irritative voiding and urge incontinence uninhibited bladder contractions were eliminated. Of 3 patients with an indwelling urethral catheter for incontinence due to detrusor hyperreflexia 1 was converted to intermittent self-catheterization. Whereas bladder capacity, compliance, sensation and voiding pressures were not different after continuous intrathecal baclofen, when a mean of all patients was compiled, a 72% increase in capacity and 16% improvement in compliance were observed in subjects without cervical spinal cord pathology. Detrusor-sphincter dyssynergia was abolished in 40% of the patients. Continuous intrathecal baclofen may represent a novel approach to the management of patients with a neurogenic bladder who have decreased bladder compliance and detrusor hyperreflexia not controlled by oral medications.