A swollen, red, or painful penis can usually be categorized as a disorder of the foreskin or of the shaft of the penis. The most common abnormalities of the foreskin are phimosis, paraphimosis, and balanoposthitis. Penile shaft disorders occur less commonly and include priapism, tourniquet syndrome, and zipper injury.
Phimosis is caused by stenosis of the distal aspect of the foreskin, preventing retraction of the foreskin over the glans. There may be a history of ballooning of the foreskin during urination, with dribbling of entrapped urine after voiding is complete (Figure 133-3). Most uncircumcised infants have normal, physiologic phimosis. Nearly all cases of physiologic phimosis spontaneously resolve by 5 years of age and rarely require treatment other than daily cleaning while bathing. If a patient has persistent phimosis beyond school age and the parent desires treatment, topical steroid cream can be effective.10,11 Acquired cases of phimosis may be secondary to recurrent balanoposthitis, poor hygiene, or forcible retraction of the foreskin. Acquired cases are often refractory to medical management and may ultimately require circumcision. One of the few true emergencies related to phimosis occurs when the foreskin is nearly completely sealed off, causing acute urinary retention. Such cases may require dilation of the foreskin under procedural sedation or dorsal penile block to place a Foley catheter.
Phimosis in a toddler leading to ballooning of foreskin caused by entrapped urine.
Paraphimosis is a true urologic emergency. This occurs when a tight ring of phimotic foreskin is retracted proximal to the glans and becomes trapped in that position. Subsequent impairment of venous and lymphatic drainage causes progressive swelling of the glans and foreskin. If the paraphimosis is not promptly reduced, arterial blood supply becomes compromised, and the glans may necrose.
Symptoms of paraphimosis are pain, erythema, and swelling of the shaft and glans, distal to the constricting ring of foreskin (Figure 133-4). The area of the shaft proximal to the constriction appears normal. Because delay in reduction will lead to worsening edema resulting in a more difficult manual reduction, paraphimosis should be reduced as soon as possible. Mild paraphimosis may be manually reduced without the need for sedation or analgesia. More difficult cases will require either a dorsal penile nerve block or procedural sedation, depending on the age and degree of cooperativeness of the patient.
A 12-year-old boy with paraphimosis for more than 24 hours.
The dorsal penile nerve provides most of the somatosensory innervation to the shaft and glans penis. The dorsal penile block (Figure 133-5) is useful for minor painful procedures of the penis, such as paraphimosis reduction, dorsal slit procedure, or zipper entrapment release. Using a 25- or 27-gauge needle, inject lidocaine hydrochloride without epinephrine into the base of penis, at the junction between the penis and the suprapubic skin, off the midline to avoid the superficial dorsal vein. Inject the lidocaine just deep to the Buck fascia, which is located 3 to 5 mm beneath the skin.
Dorsal penile block. Local anesthesia infiltration around the base of the penis. Black dots represent the locations of the skin wheals. [Reproduced with permission from Reichman EF, Simon RR: Emergency Medicine Procedures, Copyright © 2004, The McGraw-Hill Companies, Inc., all rights reserved. Section 10. Genitourinary Procedures, Chapter 125, Anesthesia of the Penis, Testicle, and Epididymis, Figure 125-3.]
A slight "pop" is usually felt as the needle passes through the fascial layer. Aspirate before injecting the lidocaine, because the dorsal arteries and veins are within close proximity to the nerve. Depending on the size of the child, between 1 and 5 mL of lidocaine should be used. Half of the volume is injected at the 10 o'clock position, with the other half injected at the 2 o'clock position. Another technique involves injecting only once at the midline through the Buck fascia, with injection of the full volume directed toward each direction after negative aspiration of blood. Like most nerve blocks, optimal analgesia is achieved after 5 minutes.
Once analgesia is achieved either by dorsal nerve block or procedural sedation, manual reduction of the paraphimosis may be attempted. To decrease penile edema, it is often helpful to use a bag of ice (for 3-minute increments to avoid cold injury) or manual compression before attempting reduction. Squeezing the glans and swollen foreskin using one's palm or a compression dressing for 5 minutes usually decreases the edema to allow successful manual reduction. The most common technique for manual reduction involves placing both thumbs over the glans, with both index fingers and long fingers surrounding the trapped foreskin. One pushes the glans back into the foreskin while pulling the foreskin back into normal position. This may require a few minutes of constant pressure before the glans slips through the paraphimotic ring (Figure 133-6).
Manual reduction of paraphimosis. After appropriate analgesia is administered, place both thumbs over the glans, with both index and long fingers surrounding the trapped foreskin. The foreskin can then be reduced by placing pressure on the glans. [Reproduced with permission from Reichman EF, Simon RR: Emergency Medicine Procedures, Copyright © 2004, The McGraw-Hill Companies, Inc., Figure 129-4.]
Manual reduction may fail if there is extreme swelling of the foreskin and glans from prolonged paraphimosis. Emergent urologic consultation is necessary for such cases. Although more invasive procedures are ideally done by a surgeon, the emergency physician may need to perform such procedures if necrosis is imminent. One commonly used technique involves using a 21-gauge needle to make multiple punctures in the foreskin followed by gentle compression, thus draining some of the edema. Manual reduction can then be attempted again. A dorsal slit procedure may be necessary if other attempts at reduction fail. This involves making a vertical incision over the constricting ring to release the paraphimosis. All cases of paraphimosis, whether simple or complicated, require follow-up with a urologist to assess healing and the need for circumcision.
Balanitis (cellulitis of the glans), posthitis (cellulitis of the foreskin), and balanoposthitis (cellulitis of the glans and foreskin) are common diagnoses in young males. Poor hygiene and phimosis predispose children to such infections (Figure 133-7). On examination, the glans, the foreskin, or both the glans and foreskin are swollen, tender, and edematous. In most cases, empiric treatment with oral antibiotics with a first-generation cephalosporin and warm soaks are sufficient. In cases in which there is an associated erythematous papular rash with satellite lesions, antifungal cream may also be indicated.
A 4-year-old boy with posthitis and phimosis.
Priapism is a prolonged, unwanted erection not associated with sexual stimulation. Low-flow (venous) and high-flow (arterial) priapism are managed differently.
High-flow (nonischemic) priapism is generally due to an arteriovenous fistula from trauma (i.e., lacerated cavernous artery shunting blood into the cavernous bodies). This can lead to a persistent partial or full erection for days to weeks, but is generally not painful. Because of the continuous inflow of arterial blood, ischemia or impotence does not occur. Therefore, high-flow priapism is not a true urologic emergency. Most cases are treated conservatively, and only a few cases require angioembolization of the lacerated artery.
Low-flow (ischemic) priapism is caused by sludging of red blood cells, leading to impaired venous drainage, venous congestion, and ischemia. In children, the most common cause of low-flow priapism is sickle cell disease.12 Other less common causes in children include illicit drugs (cocaine and cannabis), antidepressants, antipsychotics, and leukemia (presenting with extreme hyperleukocytosis).13 Low-flow priapism causes a very rigid and extremely painful erection.
The type of priapism can usually be identified by history and physical examination. Doppler US can distinguish the type of priapism, with low-flow priapism showing decreased or no blood flow in the cavernosal arteries. The most reliable method, however, involves testing aspirated blood from the corpus cavernosum for blood gas analysis. Aspiration of the corpus cavernosum should be done only by an experienced urologist. Blood from low-flow priapism will be dark in color, with a partial pressures of oxygen (PO2) <30 mm Hg, a partial pressure of carbon dioxide (PCO2) >60 mm Hg, and a pH <7.25. Cavernous blood gas from high-flow priapism is bright red in color with numeric values similar to normal arterial blood.
Without a history of pelvic, genital, or perineal trauma, nearly all priapism is low flow and usually secondary to sickle cell crisis. Priapism can occur in all forms of sickle cell disease, including sickle hemoglobin C and the sickle thalassemias. Among patients with sickle cell disease, a single episode of priapism was reported by 31% to 64% of patients, with approximately 50% reporting recurrent episodes.12 Such recurrent episodes are termed "stuttering" priapism and are unpredictable and of variable duration.
Obtain a history including the duration of symptoms and any precipitating events (i.e., medications or illicit drugs). When low-flow priapism lasts for >4 hours, the risk for permanent damage leading to impotence is significant and requires emergency urology consultation. While waiting for the urologist, administer IV fluids, opioid analgesics, and supplemental oxygen, and maintain the patient as NPO (nothing by mouth) for possible procedural sedation or operative management. If sickle cell disease is the underlying cause, treat with IV venous hydration at 1.5 times maintenance rates and consider red blood cell exchange transfusion (see chapter 142, "Sickle Cell Disease in Children"). Prolonged priapism requires concurrent aggressive urologic management with corporeal aspiration and irrigation, intracavernous injection of a sympathomimetic drug (such as phenylephrine or epinephrine), or, potentially, surgical shunting as a last resort.14 Opioids may actually prevent detumescence, whereas ketamine is an established detumescent.15 Ketamine should be preferentially considered for patients requiring procedural sedation prior to corporeal aspiration or irrigation.
TOURNIQUET SYNDROME OF THE PENIS
First reported in the literature in 1832, Reinisch and colleagues coined the term hair-thread tourniquet syndrome in 1988, when they described six cases of young infants with digit strangulation.16 In a 2004 review, among the 90 cases of tourniquet syndrome found in the literature, toes were affected in 47%, penis in 25%, fingers in 20%, clitoris in 6%, and labia in 2%.17
Tourniquet syndrome of the penis presents with penile redness, swelling, and pain. Occasionally, the presenting sign is irritability of unknown cause, so a thorough history and physical are crucial to identify a tourniquet syndrome. On physical examination, the area of the penis distal to the strangulation is erythematous, edematous, and tender. Edema often obscures the hair or thread itself. Treatment includes cutting the hair or thread if visualized, or using a depilatory agent, such as Nair®. Depilatory creams will not work on synthetic fibers, however, and if unable to remove the constriction, urologic consultation is necessary. Damage from the tourniquet can range from mild penile edema, to glandular disfigurement, urethral transaction, and even penile amputation.18 Although most cases are unintentional, they can also result from abuse.
Penile zipper entrapment is most often seen in school-age boys, most commonly when not wearing underpants. The patient's shaft, foreskin, or glans becomes entrapped between the locked teeth of the zipper or within the fastener itself (Figure 133-8). If the skin is trapped between the teeth of the zipper, cut the cloth between the locked teeth, and separate the teeth of the zipper. However, if the skin is caught within the fastener of the zipper, releasing the skin is more difficult.
A 4-year-old boy with (A) penile zipper entrapment and (B) post-zipper removal after cutting the median bar.
There are several methods described in the literature for zipper release. The most commonly used method is to use sturdy wire cutters or bone cutters to cut the median bar of the zipper (Figure 133-9). This requires a special tool, which may not be available, and in some cases the angle of the zipper and type of zipper preclude easy access to the median bar. Other methods include using a mini hacksaw to cut the median bar,19 dousing the area with liberal amounts of mineral oil and then freeing the entrapped skin with gentle traction,20 and twisting a small flat-head screwdriver between the two faceplates of the zipper to widen the gap and allow release of the tissue.21
Parts of zipper are identified for penile zipper release. The most common method is to cut the median bar, thus releasing the entrapped skin. [Reproduced with permission from Reichman EF, Simon RR: Emergency Medicine Procedures, Copyright © 2004, McGraw-Hill, New York, Figure 131-1.]
The age and degree of cooperativeness of the patient will determine type of analgesia and/or sedation needed. The patient may need oral analgesics, IV analgesics, or a dorsal penile block with or without procedural sedation. If all attempts fail at bedside zipper release, consult the urologist for removal under general anesthesia in the operating room.