Risk Factors for Surgical Shunting in a Large Cohort With Ischemic Priapism
Hanson Zhao MD; Kai Dallas MD; John Masterson MD; Eric Lo BA; Justin Houman MD; Carl Berdahl MD, MS; Joshua Pevnick MD; Jennifer T. Anger MD, MPH
FIRST PUBLISHED: November 15, 2020 – The Journal of Sexual Medicine
Ischemic priapism is a medical emergency. Left untreated, men may develop smooth muscle necrosis, corporal fibrosis, and erectile dysfunction.
Guidelines set forth by the American Urological Association and the European Association of Urology agree that treatment for ischemic priapism “should consist of a stepwise algorithm starting with corporal irrigation and injection of a sympathomimetic agent.” If these approaches are not successful, a surgical shunt may be the next step.
In some cases, it could be worthwhile to proceed to directly to shunting, as corporal irrigation and sympathomimetic agent injections “can delay the time to detumescence, cause significant discomfort, and subject the patient to unnecessary morbidity.”
The current study discusses possible risk factors for surgical shunt placement.
A manual chart review was conducted for patients presenting at one institution from January 1, 2010 to July 1, 2018. Collected data included demographics as well as priapism type, etiology, duration, and treatment.
Over the 9-year period, 143 patients (mean age 45.5 years) had 169 ischemic priapism encounters. Approximately 49% of the cases were caused by recreational intracavernosal injections (ICIs), defined as “using an intracavernosal agent without a prescription.” One quarter of the cases were the result of a urologist-prescribed ICI. The remaining cases were associated with phosphodiesterase type 5 inhibitors (5%), sickle cell conditions (4%), trazodone (5%), other medications (5%), and unknown causes (7%).
Almost 15% of the cases resolved spontaneously.
Twenty-six men (15%) underwent surgical shunt placement. In this group, 23 men had a phenylephrine injection and corporal irrigation before receiving the shunt.
Priapism duration data was available for 160 patients. In this group, men who received shunts tended to have longer durations (median 36 hours) compared to men who did not receive shunts (median 10 hours).
Longer priapism duration and having a history of priapism were considered independent predictors for surgical shunting.
In a subgroup of 125 men who had priapism durations of less than 24 hours, 5% received a shunt. However, in a subgroup of 25 men whose priapism lasted 24 hours or longer, 57% underwent shunt procedures.
Duration of Priapism
Duration of priapism is an independent risk factor for surgical shunting. An “optimal cutoff time” for priapism duration is 24 hours.
There is histological evidence that, after 24 hours of ischemia, tissue damage – including smooth muscle necrosis, fibroblast proliferation, and endothelial lining destruction – is present.
Therefore, for men whose priapism has exceeded the 24-hour mark, proceeding directly to shunt placement (after a short trial of irrigation/sympathomimetics) could be beneficial.
History of Priapism
Having a history of priapism is also an independent risk factor for shunting. Men who have had priapism may already have some degree of corporal fibrosis and scarring, which could reduce blood flow. In addition, these men might not respond well to corporal irrigation and alpha agonist therapy.
An estimated 57% of men with prolonged ischemia develop erectile dysfunction. Clinicians should let patients know of this possible consequence.
Several limitations were acknowledged, including the following:
- The study had a retrospective design.
- Findings come from one institution.
- Duration of priapism information comes from chart review and may not be accurate.
- It is not known how priapism etiology affected treatment response.
- It was unknown how much time delay occurred between corporal irrigation/phenylephrine injections and shunting.
- Both proximal and distal shunts were considered in the study. While both are surgical shunts, they may lead to different results.
“To minimize the morbidity and time delay associated with corporal irrigation and injection of sympathomimetics, urologists may consider proceeding to shunt placement for cases of priapism that present with a duration longer than 24 hours or for patients with a past history of priapism.”