Effect of phosphodiesterase type 5 inhibitors on sperm motility and acrosome reaction: An in vitro study.

PURPOSE: Phosphodiesterase type 5 (PDE5) inhibitors are effective treatments for erectile dysfunction, and several recent studies have reported positive effects of PDE5 inhibitors on semen parameters as well. However, the data are still controversial. We investigated the effect of PDE5 inhibitors on sperm function by analyzing sperm motility and acrosome reaction. MATERIALS AND METHODS: This study included young healthy men who underwent fertility evaluation; 32 cases were finally included. Men were excluded if they used a PDE5 inhibitor within 2 weeks or if they had insufficient semen volume (≤2 mL), leukocytospermia, or a genitourinary infection. Changes in sperm motility and acrosome reaction were determined after in vitro exposure to the maximal semen concentration of oral intake of sildenafil (100 mg) or tadalafil (20 mg). RESULTS: Mean age of the participants was 35.4±4.9 years, mean sperm concentration was 68.7±32.4 ×106/mL, and mean sperm motility was 50.38%±8.41%. All three groups (control, sildenafil, tadalafil) experienced trends of decreased average sperm motility over time, but these changes were not significant. There were no significant differences between the three groups in the acrosome reaction after 120 minutes of drug exposure, either. The maximal semen concentration of oral intake of sildenafil (100 mg) or tadalafil (20 mg) did not substantially affect sperm motility or acrosome reaction. CONCLUSIONS: Our results suggest that on-demand use of a PDE5 inhibitor is safe and useful for the male partner of an infertile couple; however, further studies are warranted for daily PDE5 inhibitor use.

Ultrasound-Guided Block of the Axillary Nerve: A Prospective, Randomized, Single-Blind Study Comparing Interfascial and Perivascular Injections.

BACKGROUND: The ultrasound-guided block of the axillary nerve may be complicated in cases in which the posterior circumflex humeral artery (PCHA) follows an abnormal course. OBJECTIVES: To develop a new technique that does not rely on direct visualization of the PCHA or the axillary nerve, and to compare interfascial injection and conventional perivascular injection for a block of the axillary nerve. STUDY DESIGN: A prospective randomized study. SETTING: An interventional pain-management practice in a university hospital. METHODS: A total of 56 patients received ultrasound-guided block of the axillary nerve with either interfascial injection (IF Group) or perivascular injection with nerve stimulation (PV Group). The primary outcome was procedure duration, defined as the time interval from when the transducer contacted the skin to when the needle was removed from the skin. RESULTS: The mean procedure time was significantly shorter in the IF Group than in the PV Group (64 seconds [SD 28.3] vs. 135 seconds [50.3], difference of -71.4 seconds; 95% confidence interval, -93.2 to -49.5) (P < 0.001). There were no differences in secondary outcomes, including the quality of blocks, between the 2 groups. LIMITATIONS: The practitioner was not blinded to the group to which the patients belonged. CONCLUSIONS: Ultrasound-guided block of the axillary nerve with interfascial injection can be performed without placing the needle near the PCHA. KEY WORDS: Block of axillary nerve, ultrasound-guided block, posterior circumflex humeral artery, interfascial injection.