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Priapisms in General

Considerations and Causes

• Definition: erection > 4 hours beyond or unrelated to sexual stimulation
• Sickle cell: cause of 1/3 total cases worldwide
• ED therapies: priapism more common with ICI than with oral agents, 5% with titration in office, 0.4% with self-therapy, more common with papaverine and phentolamine than alprostadil

Workup

• Heme/Onc Hx: sickle cell, thalassemia, blood dyscrasia, malignancy
• Trauma: penile/perineal trauma, spinal cord injury
• Medications (prescribed): a-antagonists, anticoagulants (heparin, warfarin), hydroxyzine, hydralazine, propranolol, atomoxetine, ED agents
• Medications (psych meds): trazodone, bupropion, chlorpromazine, clozapine, fluoxetine, lithium, olanzapine, risperidone
• Medications (recreational): alcohol, cocaine, marijuana, amphetamines
• Medications (inpatient): TPN, IV contrast, spinal/general anesthesia
• Symptoms: duration, pain, prior priapism episodes and their treatments
• Labs: check penile blood gas and CBC, consider urinary toxicology screen and hemoglobin electrophoresis
• Doppler: only use if unclear whether ischemic or non-ischemic

Ischemic Priapism

Evaluation/Diagnosis

• Definition: erection with little/no cavernous arterial inflow (compartment syndrome of the penis)
• Pain: common presenting symptom, takes 6-8hrs to develop
• ED risk: high risk (75-90%) of permanent erectile dysfunction after 24-48hr
• Penile blood gas: expect low pH (< 7.25), low oxygen (< 30), high CO₂ (> 60)

Stuttering Priapism

• Most often seen in sickle cell patients (29-42% lifetime recurrence)
• Labs: anemia, elevated LDH, bilirubin, AST, reticulocytes, WBC, and platelets
• Immediate treatment: oxygenation, alkalinization, and exchange transfusion (discuss with hematology first)
• Commonly wakes patient up from sleep (occurs with nocturnal erections)
• Long-term treatment: leuprolide, finasteride, sildenafil, hydroxyurea, baclofen, ketoconazole
• Can consider self-injection of phenylephrine
• Do not start GnRH agonists or antiandrogens if patient has not completed puberty

Non-Surgical interventions

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• Perform penile nerve block prior to aspiration/irrigation
• Aspiration: results in detumescence in 36%, aspirate until fresh blood visualized (not dark blood)
• Technique: aspirate with 19g needle at 3 or 9 o'clock to avoid neurovascular bundles, inject saline intermittently, cold saline works better (do not use in sickle cell patients)
• Phenylephrine: inject 100-200μg/mL with 1mL q3-5 minutes, to maximum dose 1mg, monitor BP while injecting to assess for hypertension and reflex bradycardia
• PO meds: pseudoephedrine and terbutaline have 28-36% efficacy, not recommended for acute management (potentially no better than placebo)
• After ICI: 200μm phenylephrine injection without aspiration (if < 4hr)
• Wrap with gauze + coban to prevent swelling and hematoma

Distal Shunts (general anesthesia recommended)

• Purpose: reoxygenation via relieving venous outflow, by creatining fistula between corpora and glans penis, will eventually close off
• Ebbehoj: straight incision (longitudinal) with #11 scalpel through glans into corpora
• Winter: place large-bore needle, angiocatheter, or Tru-cut needle through glans into corpora, reportedly least effective
• T-shunt: insert #10 scalpel longitudinally through glans into corpora, then rotate laterally (away from urethra) and remove, perform unilaterally then bilaterally if no resolution within 15min
• Al-Ghorab: 2cm transverse incision through glans distal to coronal sulcus and excision of tunica albuginea between glans and corpora
• Corporal snake: Perform Al-Ghorab, then insert 7/8 Hegar dilator through the tunical window
• Success: bright red blood aspirated, decreased intracavernosal pressure, penile detumescence and refilling, normal penile blood gas
• Tips: avoid compressive dressing, encourage squeezing to maintain patency, and consider anticoagulation (preoperative ASA 325 + SQH then ASA 81 x2 weeks)
• Complications: edema, hematoma, infection, conversion to high-flow, fistula, necrosis, and pulmonary embolism

Other options

• Proximal shunts: higher rates of erectile dysfunction and less preferred compared to distal shunt with tunneling
• Quackels: anastomose corpus to spongiosus, stagger on shaft if bilateral to prevent urethral stricture, can also cause fistula and cavernositis
• Grayhack: anastomosing saphenous vein to corpora, can lead to pulmonary embolus
• Barry: anastomosing deep dorsal vein to corpora
• Penoscrotal decompression: perform corporotomy similar to IPP placement, use pediatric Yankauer suction tip to remove clotted/fibrotic tissue (less destructive than actual IPP placement), can perform unilateral or bilateral
• IPP placement: consider if shunts fail, avoids corporal fibrosis and preserves penile length, but higher risk of complications than average IPP patient

Other Priapisms

Non-ischemic priapism

• Definition: persistent erection from unregulated arterial inflow, but no hypoxia
• Presentation: no pain, usually report history of penile/perineal trauma
• Not an emergency, penis not ischemic
• Spontaneous resolution: up to 62%
• Aspiration: only indicated for diagnosis, no benefit for treatment
• Selective embolization: indicated for immediate relief, demonstrates arteriolacunar fistula, embolize with agent of choice (non-permanent preferred), success rates 89-100%, erectile function rates 75-86%
• Selective embolization: perform after formation of pseudocapsule otherwise can result in ligation of cavernous artery

Malignant Priapism

• Cause: most common with GU malignancy (69%), then rectal cancer
• Normal priapism management not effective or recommended
• Distal resection: consider if lesion can be completely resected
• Penectomy: consider for intractable pain, obtain MRI to assess proximal extent
• Other surgical therapies: dorsal nerve resection, SPT placement
• Radiation: usually unsuccessful
• Median survival 5-14 months