Priapism Induced by Intracavernous Injection of Vasoactive Agents: Experience in 133 Patients

Ahn, Seung Yong; Kim, Sae Chul

Abstract

Recently, the priapism is mostly seen after intracavernous injection of vasoactive drugs for the diagnosis and therapy of erectile dysfunction. Prompt relief of the priapism is essential to prevent ischemia and fibrosis of the corpora with resultant impotence. Of 2992 patients who have used intracavernous injection of vasoactive agents for diagnostic and therapeutic purposes of erectile dysfunction (August 1986-June 1995), 133 men (4.4%) experienced priapism persisting for more than 4 hours. Mean patient age was 45.6 (23-70) years. The etiology of impotence was psychogenic in 60.2%, unclear in 16.5%, vasculogenic in 10.6%, diabetogenic in 8.3%. The vasoactive agents used for the intracavernous injection were: 1) papaverine, 2) dimix; a mixture of papaverine (27. 3mg/ml) and phentolamine (0.9mg/ml), 3) trimix; a mixture of papaverine (18.8mg/ml), phentolamine (0.5mg/ml) and PGE1 (6.3mg/ml). The incidence of priapism was 3.8% in papaverine, 7. 7% in dimix and 0.7% in trimix. The average doses of papaverine, dimix and trimix to have developed the priapism were 30.3+/-9.8mg, 0.4+/-0.3ml and 0.15+/-0.1ml, respectively. Average duration of the priapism was 8.6 (4-59) hours. Priapism usually developed during diagnostic workup (63.2%) and initial dose determination phase of treatment (32.3%). The priapism resolved spontaneously in 44.4%. The priapism was treated by aspiration alone in 17.3% and irrigation with 0.1% epinephrine solution in 37.6%. One patient required cavernosaphenous shunt operation. The potency became worse after resolution of the priapism in 5 among 34 patients of follow-up. The etiology of impotence in these 5 men was vasculogenic (1/3), psychogenic (2/22) and unclear (2/4). In conclusion, trimix is the best drug among the 3 regimens for the intracavernous self-injection in terms of lowest incidence of drug-induced priapism. Vasculogenic impotence patient seems to have a greater risk of worse potency after resolution of the priapism.