|Non-ischemic (high-flow)||Ischemic (low-flow)|
|Physical Exam||Typically painless, not fully tumescent||Painful, fully tumescent with corpus cavernosa rigidity without involvement of corpus spongiosum and glans penis|
|Aetiology||High-flow priapism is extremely rare and most commonly associated with antecedent trauma including blunt trauma, or resulting from needle injury of the cavernosal artery.||Low-flow priapism is caused by impaired relaxation and/or paralysis of cavernosal smooth muscle and in sickle-cell disease|
Evidence-based guidelines and expert panels recommend the following in the management and treatment of pain crisis:
- Initiate analgesia within 30 minutes of triage. (Consensus – Panel Expertise)
- Employ individualized prescribing and pain monitoring protocols. (Consensus – Panel Expertise)
- If no contraindications, give NSAIDs as adjuvant pain therapy. (Moderate Recommendation, Low-Quality Evidence)
- Avoid meperidine (pethidine) (normeperidine, the active metabolite of meperidine, is excreted by the kidneys, and is associated with an increased incidence of seizures in the setting of renal dysfunction – common in occlusive crisis)
- One of the reasons that managing Sickle Cell pain crises can be challenging is that we often under-dose analgesics in these patients. Use IV opiods for rapid effect. The subcutaneous route is more reliable than the IM route if no IV available. Use NSAIDS sparingly in Sickle Cell Disease! While NSAIDs for acute pain crises have been shown to be effective in reducing pain and decreasing hospital length of stay, many patients with sickle cell disease have progressive chronic renal failure as a result of renal infarcts and their serum creatinine level may appear normal despite this.
- Boluses of IV fluid should NOT be given unless patients are overtly hypovolemic (sepsis, diarrheal illness, vomiting). In these situations, resuscitate only to euvolemia and for maintenance fluids use a hypotonic solution such as ½ NS or D5-½ NS.
- In patients presenting with simple pain without other symptoms who are not being admitted, lab tests are generally NOT necessary. The reticulocyte count is the most useful blood test in those patients who present with complicated pain crises.