Objective: The transversus abdominis plane (TAP) block anesthetizes the anterior branches of spinal nerves that innervate the abdominal wall from T6 to L1 dermatomes and provide effective postoperative analgesia after abdominal surgery. Several applications of TAP catheters are described for both acute and chronic abdominal wall pain, but there are no reported cases of TAP catheters used during pregnancy.
Case report: We present the case of a 23-year-old primigravida admitted to the hospital on multiple occasions during her pregnancy for right lower quadrant abdominal "stabbing" pain, with a visual analog scale score intensity of 8/10 abdominal pain. The diagnosis was unclear despite the presence of prominent ileocolic lymph nodes visualized on magnetic resonance imaging. The abdominal pain persisted despite escalating doses of intravenous opioids (up to 30 mg of intravenous hydromorphone daily). At 34 weeks' gestation, a right-sided TAP block with 0.25% bupivacaine was inserted under ultrasound guidance, and this relieved all of her pain (visual analog scale score, 0). The patient was managed with repeated boluses of 0.5% ropivacaine via a TAP catheter, which resulted in complete resolution of her pain within 3 days and allowed for complete discontinuation of opioid medications. The patient was discharged home, with no recurrence of pain. She had an uneventful cesarean delivery at term.
Conclusions: A TAP catheter inserted under ultrasound guidance can be effective for the treatment of chronic abdominal pain during pregnancy and may provide an alternative analgesic modality when intravenous opioids are not providing relief or when neuraxial analgesia techniques are not feasible or contraindicated.