A 32-year-old woman weighing 70 kg (male by sex) with a history of asthma and gender dysphoria was scheduled to undergo orchiectomy, penectomy, clitoroplasty, labiaplasty, and vaginoplasty. In the preoperative area, she received 1000 mg of oral acetaminophen, 600 mg of oral gabapentin, and a scopolamine patch. Upon entering the operating room, she was given 2 mg of intravenous (IV) midazolam for anxiolysis, and she was sat up. Standard monitors were attached, and her back was sterilely prepped; using a low-frequency curvilinear transducer in parasagittal orientation (rC60xi, SonoSite SII, FUJIFILM SonoSite Inc., USA), the right-sided ribs were counted, starting rostrally at the neck until T11 was located. The probe was moved medially to locate the transverse process (TP). Under ultrasound guidance, a 21 g nerve block needle (SonoPlex STIM, Pajunk Medical Systems L.P., USA) was inserted in-plane rostral to caudal until the TP was contacted (Fig. 1A); after aspiration demonstrated no blood return, a bolus of 35 ml of 0.25% plain bupivacaine mixed with 1 : 200.000 epinephrine was injected through the needle. This was repeated on the left side. The ultrasound was then used to demonstrate lung sliding bilaterally (Fig. 1B), confirming no pneumothorax after the nerve block. The patient was laid back and induced with 70 mg IV lidocaine and 100 mg IV propofol followed by 50 mg IV rocuronium; mask ventilation and intubation proceeded uneventfully. During the 4-hour surgery, she was maintained on a propofol drip at 75 μg/kg/min and sevoflurane at an end-tidal concentraion of 1%; as part of a multi-modal regimen, she received dexamethasone 8 mg IV, ketamine 50 mg IV, dexmedetomidine at 0.3 μg/kg/h (total 71 μg), and esmolol at 35–50 μg/kg/min. No opioids were administered, nor additional local anesthetic injected by the surgeon, and 2200 μg of phenylephrine were required to maintain systolic blood pressures in the 90s of mmHg (preoperative blood pressures 116/77 mmHg).

Extubation was uneventful, and the patient complained of minimal pain, specifically, she stated that she had more “gas pain, than surgical pain,” requiring only 50 μg fentanyl, 30 mg ketorolac, and 5 mg oxycodone in the post anesthesia care unit Her post-operative pain regimen included acetaminophen 1000 mg orally every 6 hours and ibuprofen 600 mg orally every 6 hours with breakthrough oxycodone (5–10 mg every 3-4 hours when necessary); on postoperative day (POD) 0, she tolerated food and requested 10 mg oxycodone in addition to simethicone for gas pain. Unfortunately, the patient developed bleeding from her surgical site and required a return to the operating room early on POD 1 for an exam under general anesthesia, during which she received 2 mg IV midazolam, 50 μg IV fentanyl, and 50 mg IV ketamine. No source was found, and she was re-packed and transferred to the floor. Her consequent hospital course was unremarkable, with the patient repeatedly stating her pain was well controlled. She required only 70 mg oxycodone over the next 2.5 days, after which she was discharged home.

TBS involves sensitive anatomy, and beyond a single published abstract suggesting the use of pudendal nerve blocks for post-operative pain control, guidance relies on opinion [5]. There are no previously published cases demonstrating the efficacy of the ESP block for genital surgery, possibly because the innervation involves sacral nerve roots. We used a high volume of local anesthetic to ensure spread; indeed, the ESP block facilitated the minimization of opioids during hospital stay while still affording excellent pain control.