Acute Ischemic Priapism Secondary to Sickle Cell Disease
This patient has acute ischemic priapism, a urologic emergency requiring immediate intracavernous intervention with aspiration and phenylephrine injection, not systemic sickle cell treatment alone. 1
Clinical Presentation
This presentation is classic for acute ischemic priapism in a patient with sickle cell disease:
- Painful, rigid erection of the corpora cavernosa with normal scrotum (corpus spongiosum and glans are typically spared) 1
- Morning occurrence is characteristic, as patients with sickle cell disease often experience stuttering priapism episodes upon awakening due to nocturnal surges in cyclic GMP that go unchecked 2
- The rigid penis indicates full corporal tumescence, distinguishing this from non-ischemic priapism which presents with only partial tumescence 1
Immediate Diagnostic Steps
Obtain a corporal blood gas immediately to confirm ischemic priapism, though in a patient with known sickle cell disease presenting with classic symptoms, this may be omitted at clinician discretion if the diagnosis is abundantly clear 1. Ischemic priapism shows:
- PO2 < 30 mm Hg
- PCO2 > 60 mm Hg
- pH < 7.25 1
Do not delay treatment to obtain blood gas if the clinical picture is clear 1.
Critical Management Principle
Systemic treatment of sickle cell disease alone (hydration, oxygen, transfusion, alkalization) should NEVER be the only treatment for ischemic priapism. 1 This is a compartment syndrome requiring direct intracavernous intervention. Studies show 0-37% resolution with systemic therapy alone, and delays in penile-directed treatment result in permanent erectile dysfunction 1.
Stepwise Treatment Algorithm
Step 1: Immediate Intracavernous Intervention
Begin with therapeutic aspiration using a 19 or 21 gauge needle inserted into the corpus cavernosum 1:
- Aspirate old blood to lower intracorporal pressure
- May irrigate with normal saline
- This alone achieves resolution in only 24-36% of cases 1
Step 2: Intracavernous Phenylephrine
If aspiration fails, immediately inject intracavernous phenylephrine (with or without continued irrigation) 1:
- Resolution rates of 43-81% with sympathomimetics versus 24-36% with aspiration alone 1
- Repeated phenylephrine injections should be performed before considering surgery 1
- Lower risk of post-priapism erectile dysfunction compared to aspiration alone 1
Step 3: Concurrent Systemic Sickle Cell Management
While performing intracavernous treatment, concurrently initiate standard sickle cell crisis management 1:
- Hydration
- Analgesia
- Oxygen
- Consider exchange transfusion
- But never delay penile intervention for systemic treatment 1
Step 4: Surgical Shunting if Medical Management Fails
If sympathomimetic injections fail, proceed to distal shunting procedures 1.
Prognosis and Counseling
Counsel the patient immediately that erectile dysfunction risk correlates directly with duration of priapism 1:
- <12 hours: 100% return of functional erections 3
- 12-24 hours: 78% return of functional erections 3
- 24-36 hours: 44% return of functional erections 3
- >36 hours: 0% return of spontaneous functional erections; likelihood of recovery is extremely low 1, 3
Common Pitfalls to Avoid
- Never treat with systemic sickle cell therapy alone - this delays definitive treatment and guarantees erectile dysfunction 1
- Do not wait for laboratory results if the clinical diagnosis is clear in a known sickle cell patient 1
- Do not perform penile duplex Doppler ultrasound in the emergency setting when diagnosis is clear by history and exam 1
- Do not proceed directly to surgery without attempting repeated phenylephrine injections 1
Additional Laboratory Considerations
In sickle cell patients with acute ischemic priapism, expect 1, 4:
- Lower hemoglobin than baseline
- Elevated lactate dehydrogenase, bilirubin, AST
- Elevated reticulocyte count
- Elevated white blood cells and platelets
- These findings do not change the need for immediate intracavernous intervention 1