Priapism

Persistent erection > 4 hrs, outside of sexual stimulation

Ischemic - emergent Non-ischemic - non-emergent
low flow, veno-occlusive high flow, arterial
↓ venous outflow from cavernosa → ↑ pressure and ↓ arterial inflow → hypoxia, acidosis ↑ arterial inflow without ↓ venous outflow → hypoxia, acidosis
Painful, fully rigid Non-painful, partially rigid
Aspirate: dark red blood Aspirate: bright red blood
Etiology: sickle cell disease, medications (trazodone (α1 blocker), PDE-5 inhibitors), etc.
Much more common than non-ischemic/high-flow priapism		 Etiology: blunt trauma (fistula between cavernous artery and corpora)
  • CBC/coags
  • Consider sickle cell testing in black patients with ischemic priapism
    • Generally associated with sickle cell disease >> trait
  • Cavernosal blood gas can differentiate between ischemic/venous (emergent) vs. non-ischemic/arterial (non-emergent) priapism
    • Use ABG kit and send on ice
  •   Ischemic Non-ischemic
    PO2 < 30 > 90
    PCO2 > 60 < 40
    pH < 7.25 7.40
  • Corporal doppler ultrasound can be used to assess cavernosal blood flow

 

Treat to prevent erectile dysfunction (ischemic: 50% in < 12 hours, 100% if > 36 hrs)

Ischemic: corporal aspiration or shunt

  • Pain control - dorsal penile block
  • Corporal aspiration - 18 ga needle x 2 at penoscrotal junction in 3 and 9 o'clock position (to avoid dorsal nerve bundle). Compress shaft and aspirate, repeat until bright red blood appears. 
    • May irrigate with cold saline to get clots out if priapism is prolonged, but limited data on efficacy
    • Phenylephrine (α agonist) may be injected - 1 mL of 100-500 mcg/mL solution q3-5 min, alternating with aspiration. Max dose 1 mg
      • Neostick from pharmacy is the correct concentration (100 mcg/mL), but don't give more than 1 stick = 10 cc = 1 mg
      • Systemic effects: HTN/tachy and reflex brady (have them on tele)
      • Will not work if priapism is so long that blood has clotted
  • Shunt - if 1 hour of aspiration + phenylephrine fails. Squeeze dark/hypoxic blood until bright red blood appears
    • Attempt distal shunt first (least to most aggressive)
      • **hide**Winter - insert biopsy needle into glans and excise cores from distal corpora
      • **hide**Ebbehoj - insert scalpel into glans and make multiple punctures in corpora
      • **hide**T-shunt - T-shaped incision in glans/corpora (stick scalpel in and rotate 90 degrees). Advance to bilateral, then tunnelling/dilation if unsuccessful
      • **hide**Al-Ghorab - 2 cm transverse incision in dorsal glans 1 cm distal to corona; excise tunica albuginea from distal corpus
      • **hide**Can do corporal tunneling (eg 16-18 Fr female sound)
    • Proximal shunt if distal was unsuccessful. Higher rate of ED.
      • **hide**Quackel (corporal-spongiosum shunt). Urethral fistula less likely with more proximal incision (located more dorsally in spongiosum)
      • **hide**Grayhack (corporal-saphenous shunt)
  • Consider penile prosthesis if all else fails

Non-ischemic: observe; 62% resolve spontaneously.

  • **hide**May embolize (e.g. autologous blood clot) if does not resolve; with surgical ligation as last resort.

Prevention

  • Sickle cell - hydroxyurea
  • α agonist (eg trazodone is an α1 blocker, phenylephrine is α agonist) - some data for pseudoephedrine
  • anti-androgen - finasteride (blocks testosterone → DHT)
author: admin | last edited: July 25, 2021, 9:25 p.m. | pk: 41

  1. Pocket urology p.456