Renal hemorrhage is the most worrisome complication of percutaneous renal surgery. Between August 1983 and August 1992 we performed 2,200 percutaneous renal operations, with 17 patients (0.8%) requiring angiography and embolization for significant bleeding uncontrolled by the usual measures. The angiographic diagnoses were arteriovenous fistula in 7 patients, pseudoaneurysm in 4, fistula and pseudoaneurysm in 2, and lacerated renal vessels in 2. A total of 15 patients required no further treatment after embolization, while 2 underwent either partial nephrectomy or open exploration. No risk factors for hemorrhage could be identified. We recommend angiography and embolization under 3 conditions; 1) in the immediate postoperative period when clamping of the nephrostomy tube and a tamponade balloon catheter fail to control hemorrhage (24% of our series), 2) in the early postoperative period (2 to 7 days) when the patient requires 3 or 4 units of blood after replacement of the initial blood loss (41% of our series) and 3) for sudden hemorrhage more than 7 days postoperatively (35% of our series).
The aim of this review study is to elucidate the effects that phosphodiesterase 5 (PDE5) inhibitors exert on spermatozoa motility, capacitation process and on their ability to fertilize the oocyte. Second messenger systems such as the cAMP/adenylate cyclase (AC) system and the cGMP/guanylate cyclase (GC) system appear to regulate sperm functions. Increased levels of intracytosolic cAMP result in an enhancement of sperm motility and viability. The stimulation of GC by low doses of nitric oxide (NO) leads to an improvement or maintenance of sperm motility, whereas higher concentrations have an adverse effect on sperm parameters. Several in vivo and in vitro studies have been carried out in order to examine whether PDE5 inhibitors affect positively or negatively sperm parameters and sperm fertilizing capacity. The results of these studies are controversial. Some of these studies demonstrate no significant effects of PDE5 inhibitors on the motility, viability, and morphology of spermatozoa collected from men that have been treated with PDE5 inhibitors. On the other hand, several studies demonstrate a positive effect of PDE5 inhibitors on sperm motility both in vivo and in vitro. In vitro studies of sildenafil citrate demonstrate a stimulatory effect on sperm motility with an increase in intracellular cAMP suggesting an inhibitory action of sildenafil citrate on a PDE isoform other than the PDE5. On the other hand, tadalafil's actions appear to be associated with the inhibitory effect of this compound on PDE11. In vivo studies in men treated with vardenafil in a daily basis demonstrated a significantly larger total number of spermatozoa per ejaculate, quantitative sperm motility, and qualitative sperm motility; it has been suggested that vardenafil administration enhances the secretory function of the prostate and subsequently increases the qualitative and quantitative motility of spermatozoa. The effect that PDE5 inhibitors exert on sperm parameters may lead to the improvement of the outcome of assisted reproductive technology (ART) programs. In the future PDE5 inhibitors might serve as adjunct therapeutical agents for the alleviation of male infertility.
Obstruction of the upper urinary tract is a problem commonly faced by practicing urologists. The constant evolution in endourology has effectively facilitated minimally invasive management of upper-tract obstruction. In a case in which malignancy is the cause of obstruction, however, the situation significantly changes. Questions arise regarding the need for relieving the obstruction, the means to accomplish this, and the benefits and drawbacks of each technique regarding both their efficacy and their impact on the patients well-being and the crucial issue of quality of life in the face of malignancy.
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