Priapism (dr. rao)
Prolonged, pathologic erection of the penis for > 4 hours in the absence of sexual desire. There will be dorsal penile erection with ventral flaccidity resulting from engorgement of the dorsal corpora cavernosa.
Low-flow priapism
Decreased venous outflow results in increased cavernosal pressure
When cavernosal pressure exceeds arterial pressure, ischemia develops
Typically accompanied by significant pain due to ischemia (can be considered to be compartment syndrome of the penis)
Common causes
Pediatric: Sickle cell disease, leukemia
Adult: Intercavernosal injection (papaverine, phentolamine, PGE1), Anticoagulation, Pharmaceuticals (SSRIs, sedative-hypnotics, erectile dysfunction medications), Illicit drugs (cocaine, extasy)
High-flow priapism
Excess arterial inflow resulting in priapism
Often painless
Common causes: arterial laceration, spinal trauma
Complications: Penile fibrosis, urinary retention, incontinence, thrombosis + ischemia (resulting from blood stagnation)
Differential: normal sexual arousal, penile trauma, urethral foreign bodies, spinal cord injury, peyronie’s disease, penile implant
Dorsal nerve block: retract the penis caudally and insert a small gauge (25-27G) needle on either side of the midline at 10 and 2 o’clock, inject lidocaine (without epinephrine); you should feel a pop when you pass through Buck’s fascia to know you’re in the correct space
2. Corporal aspiration (getting blood out of the penis): insert a 19G butterfly needle into the lateral corpora at the 10 and 2 o’clock positions; aspirate 10-20 mL of blood (while the patient is squeezing the penis proximally) and send a blood gas; avoid the urethra (ventrally) and neurovascular bundle (dorsally); this can be repeated on the other side if priapism persists; a patient’s response to this treatment largely depends on how long they have had an erection
3. Corporal irrigation: if detumescence does not occur after 2 aspiration attempts of 20-25 mL each, irrigate the corpus cavernosa with 25 mL of cold (10°C) sterile saline; aspirate the fluid back after a period of 20 minutes if priapism persists
4. Phenylephrine injection squeezes the blood out of the penis and back into the body; ask the patient to squeeze the penis distally to help facilitate this, dilute to 100 mcg/mL and inject 1-2 mL q5min, to a maximum dose = 1 mg over 1 hour.
