What is the immediate treatment for priapism?

Immediate Treatment of Priapism

The immediate treatment for ischemic priapism is intracavernosal injection of phenylephrine, which has a success rate of 43-81% and is strongly recommended by the American Urological Association as the preferred sympathomimetic agent. 1

Types of Priapism and Diagnosis

Before initiating treatment, it's crucial to determine the type of priapism:

1. Ischemic (low-flow) priapism (95% of cases):

   • Painful, rigid erection
   • Diagnostic blood gas values: PO₂ ≤30 mmHg, PCO₂ ≥60 mmHg, pH <7.25 1
   • True urologic emergency requiring immediate intervention

2. Non-ischemic (high-flow) priapism (5% of cases):

   • Usually painless, partially rigid erection
   • Often related to perineal trauma
   • Not a medical emergency 2

Treatment Algorithm for Ischemic Priapism

First-Line Treatment:

1. Corporal aspiration with or without irrigation:

   • Resolution rate: 30% 1
   • Perform using 19G or 21G butterfly needle
   • Insert into lateral aspect of proximal penis
   • Aspirate 20-30 mL of blood

2. If aspiration fails, proceed immediately to intracavernosal phenylephrine:

   • Dilute phenylephrine to 100-500 μg/mL with normal saline 1
   • Administer 1 mL injections every 3-5 minutes
   • Continue for up to 1 hour if needed
   • Monitor blood pressure, heart rate (ECG monitoring for patients with cardiovascular risk factors)

Second-Line Treatment (if medical management fails):

1. Surgical shunting procedures:
   • Distal shunts (cavernoglanular/corporoglanular): First choice, resolution rate 66-74% 1
   • Proximal shunts (Quackels, Grayhack): Resolution rate 76-77%, but higher complication risk 1

Critical Time Considerations:

• Treatment efficacy decreases significantly after 48 hours
• Significant risk of erectile dysfunction after 18 hours
• Permanent erectile dysfunction likely after 36 hours 1
• For priapism lasting >36 hours, surgical interventions are likely required as medical therapy alone is unlikely to succeed due to smooth muscle apoptosis 1

Special Considerations

Sickle Cell Disease:

• Standard urologic management should not be delayed for disease-specific interventions
• Systemic treatments alone have poor resolution rates (0-37%) 1

Cardiovascular Risk:

• Phenylephrine is preferred over other sympathomimetics due to lower cardiovascular side effects 1
• Use with caution in patients with cardiovascular disease

Common Pitfalls to Avoid

1. Delayed treatment: Time is critical - each hour increases the risk of permanent erectile dysfunction.

2. Misdiagnosis of priapism type: Using sympathomimetics in non-ischemic priapism can lead to systemic absorption and toxicity 3.

3. Inadequate phenylephrine dilution: Using undiluted phenylephrine can cause severe hypertension and cardiac complications.

4. Failure to monitor vital signs: Always monitor blood pressure and heart rate during phenylephrine administration.

5. Delaying surgical intervention: If medical management fails after 1 hour, proceed to surgical options without further delay.

The European Association of Urology guidelines also emphasize that intervention should start within 4-6 hours of priapism onset to maximize the chances of preserving erectile function 2.