A 23-year-old man fell off a bull while riding and later suffered an isolated injury to the left perineal region by one of the bulls’ horns. At the emergency department, he was hemodynamically intact, and had a perineal penetrating injury measuring approximately 6 × 5 cm. Abdominal examination findings were benign. Computed tomography of the abdomen and pelvis noted approximately 35% circumferential extraperitoneal rectal injury. In addition to initiating broad-spectrum antibiotics and proctoscopy, what is the next step in management?