Priapism

Priapism is a sustained penile erection lasting more than 4 hours, neither caused by sexual excitation nor relieved by ejaculation. It can affect any age but mainly for those aged 5-10 years and 20-50 years.

Types

• Low Flow (Ischemic) Priapism

– Most Common

Pathophysiology

Decreased venous outflow from the corpus cavernosum due to:

• compression or thrombosis of the penile, prostatic, or pelvic veins
• Prolongation of tumescence
• Ischemia of the penis

Causes

• Drugs – sildenafil { used for treating erectile dysfunction } , intracavernosal injection of Alprostadil, Prazosin, Trazodone
• Hypercoagulable states include Sickle cell disease { as sickled erythrocytes block the venous drainage of the corpus cavernosum, Leukostasis reactions, Thalassemia and Fabry diseases,
• Autonomic dysfunctions include autonomic neuropathy, cauda equina syndrome, and spinal cord stenosis.
• Bladder cancer, prostatic cancer, and other tumors of the pelvis
• Can be idiopathic

Clinical features

Early presentation

1. Painful erection (similar to Peyronie disease)
2. The corpus cavernosum is entirely rigid.
3. Features of perineal trauma absent.

Treatment

a. First-line therapy

• Repeated intracavernosal injections with phenylephrine (alpha receptor agonist) – for an hour
• Aspiration of the sludged blood from the corpus cavernosum with/without irrigation with normal saline

b. Second-line therapy (if detumescence does not occur):

• Decompression of the penis – Creating a shunt between the corpus (e.g., Winter or Ebbehoj technique)

c. Supportive measures

• Oxygen,
• Analgesia (with opiates if necessary)
• hydration with IV fluids
• Patients with sickle cell disease who develop priapism require exchange transfusion.

Prognosis

• Early treatment (within 12 hours) usually allows for complete recovery.
• Late treatment almost always leads to penile fibrosis and erectile dysfunction.
• Medication (especially for erectile dysfunction) is the most common cause of low-flow

• High Flow Priapism

Etiology

• Blunt l trauma (e.g., saddle injury)
• Penetrating injury (e.g., local penile injections) → injury to the cavernosal artery → fistula between the cavernosal artery and corpus cavernosum
• Congenital vascular malformations

Pathophysiology

• Excessive arterial influx with sufficient venous outflow
• No penile ischemia

Clinical features

1. Up to a 72-hour delay from initial injury and onset of priapism.
2. There is no pain
3. Non rigid corpus cavernosum .
4. Symptoms of trauma: perineal swelling, dysuria, and hematuria.

Treatment

1. No treatment is necessary.
2. Persistent can be treated via selective arterial embolization

Prognosis: has a great prognosis, and resolve spontaneously.

• Recurrent priapism (also called stuttering priapism)

A type of ischemic priapism that occurs in men with sickle cell disease

Tests

– Analysis of Penile Blood Gas

LF priapism: shows dark blood due to hypercapnia, hypoxia and acidosis

HF priapism: shows bright red blood with the normal arterial values

– Doppler Ultrasound

LF priapism: shows poor arterial influx

HF priapism: shows high arterial influx and adequate outflow

– Other: include CBC, differential count AND peripheral blood smear