Colonic Puncture During Ilioinguinal Nerve Block in a Child

Abstract

Ilioinguinal nerve block is widely used in pediatric patients to provide postoperative pain relief after inguinal incisions. Peripheral nerve blocks are commonly believed to be extremely safe and virtually without complications [1]. We report a case of colonic wall injury after ilioinguinal nerve block. Case Report A 14-yr-old, 40-kg boy presented for spermatic vein ligation. After premedication with oral midazolam, anesthesia was induced with propofol, and the airway was secured with a size 3 laryngeal mask airway. The adolescent spontaneously breathed a mixture of nitrous oxide, oxygen, and sevoflurane. Before surgery, an ilioinguinal nerve block was performed with 30 mL of a mixture of bupivacaine 0.25% and prilocaine 1%. The injection was made using a 11/4-in. 22-gauge long bevel needle 2 cm medially in a line between the superior iliac spine and the umbilicus. A fascial pop was thought to be felt. After careful aspiration, the local anesthetic solution was thought to be partly injected under the fascia, followed by generous subcutaneous infiltration. The regional block was effective for the procedure. As the surgeon exposed the spermatic vein by a high inguinal approach, a dark blue, shining structure appeared through the peritoneal sac. The peritoneum was opened, revealing a small laceration and subserosal hematoma formation in the colon. The apparent nonperforating puncture was secured with a seromuscular suture, the peritoneum was closed, and surgery proceeded uneventfully. The immediate postoperative course was uneventful, and the patient was discharged from the hospital on Day 3. The patient presented again on Day 5 with discharge from the incision site, which was managed conservatively. Because of persistent wound tenderness a second operation was performed on Day 48, where the subcutaneous tissue showed chronic inflammatory changes. A culture of the discharge grew Staphylococcus aureus. Because of persisting groin pain and signs of acute inflammation a third operation was performed on Day 51, where no intraperitoneal fistula or abscess formation could be found. Staphylococcus aureus was again cultured. Drainage of the wound and antibiotic treatment was initiated, and the patient made a slow but complete recovery. Discussion We report a case of colonic injury with subserosal bleeding during attempted ilioinguinal nerve block, which has previously not been reported. The anesthetic complication led to a laparotomy, and the postoperative course was complicated by a superficial surgical wound infection with Staphylococcus aureus, which is a typical skin contaminant. The colonic puncture itself does not seem to have posed any threat to the patient, because at no time could signs of intraperitoneal fistula or abscess formation be found. It did, however, cause diagnostic uncertainty and trigger more extensive surgery. Ilioinguinal nerve block is generally reported to be an extremely safe procedure. However, there are side effects, such as transient femoral nerve block [2-4] and rapid absorption of the local anesthetics, resulting in high plasma levels [5], especially in young children [6]. Successful ilioinguinal nerve block depends on clear identification of the external oblique aponeurosis by feeling a loss of resistance. In this case, a standard hypodermic needle with a long bevel was used. This type of needle is still recommended and used for ilioinguinal nerve block [7]. A short-bevel needle, however, enhances the recognition of fascial planes. If this had been used, the excessive needle insertion and colonic puncture might have been avoided. This case of colonic injury demonstrates that there are complications with ilioinguinal nerve block. It also highlights the importance of selecting the optimal needle while performing regional blocks. The authors thank Susan Balogh, MD, for her help in editing the manuscript.