Priapism in adult or adolescent (excluding patients with sickle cell disease)

PCO₂: partial pressure of carbon dioxide; PO₂: partial pressure of oxygen.

* In penile cavernosal aspiration, a small caliber needle is used to aspirate 3 to 5 mL of blood from the lateral aspect of the corpus cavernosum for visual inspection and blood gas analysis.

¶ If cavernous blood gas analysis is not available, Doppler ultrasonography can detect low blood flow in the corpus cavernosum, which suggests ischemic priapism. Ultrasound may also detect cavernous arterial fistula, pseudoaneurysm, or other anatomic abnormalities that, when present, may suggest nonischemic priapism.

Δ After receiving phenylephrine, patients should be monitored for hypertension, headache, tachycardia, and arrhythmia; the treatment should be discontinued if any of these occur. If priapism is of ≥24 hours' duration, injection may be bypassed in favor of surgery.

◊ Resolution of priapism is determined by detumescence and improvement in pain. Persistent penile edema and/or partial erections may mimic unresolved priapism; verify with repeat cavernosal aspiration showing improved oxygenation and/or Doppler ultrasonography demonstrating restoration of blood flow. Priapism of ≥4 hours is associated with decreased phenylephrine efficacy. If no improvement is noted after 2 to 3 rounds of aspiration or injection, it is reasonable to stop aspiration and proceed to urologic consultation for surgery.