URODYNAMIC STUDY OF LOWER URINARY TRACT: V. Alpha Adrenergic Blocker for the Treatment of Neurogenic Bladder Dysfunction

The response of the lower urinary tract to alpha adrenergic Blocker was studied. The contractile strength of detrusor muscle remained unchanged, while static urethral resistance and stimulated dynamic urethral resistance were decreased in response to intravenous administration of alpha adrenergic blocker, which were demonstrated in male and female dogs in vivo. A series of 37 patients (24 males and 13 females) with varying degrees of neurogenic bladder dysfunction were evaluated by oral administration of phenoxybenzamine hydrochloride, alpha adrenergic blocker. 6 patients were suffering from complete supranuclear lesion, 5 incomplete supranuclear lesion, 7 complete and 19 incomplete nuclear and/or infranuclear lesion. Effective daily dose of phenoxybenzamine was found between 5 and 15mg a day, which was safe and tolerable for the majority of patients. 19 patients were treated with phenoxybenzamine, one of which had parasympathomimetics also. The rest required the combination therapy of phenoxybenzamine and intermittent self-catheterization. Objective improvement was always preceded by an improvement of subjective complaints, which was observed in 88% of patients and generally appeared in 12 to 48 hours. The significant decrease of residual urine was noted in 52% of patients. 7 patients with indwelling catheter were all liberated from it after the treatment. The maximum urethral pressure in the urethral pressure profilometry significantly decreased in 8 out of 11 cases (73%), and 60% of patients showed an improved uroflowmetrogram. 43% of the cases complained of side effects such as dizziness, nasal obstruction and orthostatic hypotension. The overall result is as follows; excellent 6 (16%), effective 22 (60%) and non-effective 3 (8%). Other 6 patients (16%) could not be evaluated, since the cessation of therapy was required by the side effect during the early course of treatment. Alpha adrenergic blocker is quite of promise to facilitate the bladder emptying in patients with neurogenic bladder dysfunction with or without the assistance by the intermittent self-catheterization. Mode of micturition has been promptly improved due to the decreased urethral resistance. No severe side effects can be expected unless the daily dose exceeds 15mg a day. It should be stressed that the conventional treatment to establish the satisfactory voiding by increasing the bladder tonicity with parasympathomimetics should now be replaced by the new method of decreasing the uret