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A perineal urethrostomy with penile amputation is a common salvage technique used for lightweight feedlot steers. This procedure is not intended for breeding individuals. Urethral stricture is an eventual complication of this technique; therefore it should be reserved for feedlot steers to resolve their azotemia and finish growth prior to slaughter. This technique is relatively quick and can easily be performed in the field.

It can be performed with the individual restrained in a chute under epidural anesthesia or in dorsal recumbency with heavy sedation and epidural anesthesia. The perineal area from the anus to the scrotum is clipped and aseptically prepped. A 10‐ to 15‐cm midline incision is made immediately caudal to the scrotum. The incision is extended through the subcutaneous tissues and semitendinosus muscles. Blunt dissection is used until the penis can be grasped. The retractor penis muscles can often be confused for the penis. The retractor penis muscles are pink, soft, and identifiable as two separate components versus the firm penis which is covered in white tunica albuginea [21]. Once the penis is grasped, firm traction is used to pull the penis caudodorsally toward the skin incision, while the retractor penis muscles can be reflected or sharply dissected. Caudal traction and dissection are performed until a 6‐cm segment of penis can be exteriorized without tension [21]. If substantial subcutaneous urine accumulation has occurred, the penis can separate from the preputial attachments, allowing exteriorization of the entire penis [4]. The dorsal penile artery and vein are identified and ligated approximately 5 cm distal to the dorsal aspect of the skin incision [21]. The penis is transected distal to this ligature. However, removal of the distal penis requires substantial dissection of the preputial attachments in cases with urethral obstruction but absence of urethral rupture. In these cases, the dorsal penile vasculature should remain intact and be blunted dissected and reflected from the penis.

Once the penis is transected, it is turned over 180° with the urethra now oriented dorsally. A horizontal mattress pattern using a monofilament non‐absorbable suture is made through the corpus cavernosum to secure the penile stump to the skin [4, 21]. Caution should be used to not incorporate the urethra; a retrograde polypropylene catheter may be placed to ensure inadvertent urethral involvement is avoided (Figure 20.8). To assist with prevention of urine scald, the stump should extend 2–3‐cm from the skin incision [21]. Spatulation of the urethra is optional (Figure 20.8). If performed, the urethra is incised from the distal aspect of the penile stump to the proximal aspect of the incision. The urethral mucosa and tunica albuginea are sutured to the skin using an absorbable 2–0 monofilament suture in a simple continuous or interrupted pattern. Spatulation of the urethra is performed to decrease the rapidity of urethral stricture formation [21]. The skin remaining proximal and distal to the urethrostomy site is closed in a routine fashion.

Figure 20.8 Perineal urethrostomy showing spatulation of the urethra and use of polypropylene catheter to assist with urethra location during suturing.

For individuals with a urethral rupture, subcutaneous skin incisions should be made as/if needed to drain any subcutaneous urine accumulation. Individuals with uroabdomen should have abdominal drainage of urine performed.

Potential complications from this procedure include postoperative hemorrhage from the corpus cavernosum of the penile stump and hemorrhage from repeated trauma to the penile stump. A securely fitted urethral catheter can be placed to put pressure on the corpus spongiosum to assist with hemorrhaging. Other common complications include urine scald, urethral stricture, and reobstruction with blood or calculi.