A case of priapism following intrathecal morphine injection in a dog.

ABSTRACT

Background: Priapism refers to prolonged erection unrelated to sexual stimulation, with severe sequelae unless treated. In humans, it is a rare complication associated with epidural or spinal opioid administration. Its pathophysiology is unclear. This is the first report of priapism following neuraxial anesthesia in dog. Case Description An intrathecal morphine injection (30 mcg/kg) at L5-L6 for postoperative analgesia was given at the end of surgery for removal of cutaneous mastocytomas of the abdomen and left axillary lymphadenectomy. Painless penile erection occurred 2 hours later and lasted 6 hours, before spontaneously resolving 7-8 hours after the injection. No pain or other adverse events (e.g., nausea, urinary retention, and itching) were recorded. Recovery was complete without treatment. Conclusion: Painless, self-resolving priapism is a rare complication associated with intrathecal morphine injection in dogs.