Introduction: Bladder transplantation has not yet been successfully performed. Technical challenges include complicated deep pelvic vascular anatomy, limited visualization, and procedural complexity. In preparation for a first-in-human clinical trial of bladder transplantation (NCT05462561), we describe our pre-clinical experience with robotic vascularized composite bladder allograft (VCBA) autotransplantation. Methods: VCBA autotransplantation was performed in three settings: living porcine, pulsatile human cadaver, and brain-dead heart-beating deceased research donor. A robotic approach was utilized to optimize visualization in the deep pelvis and maximally preserve allograft perfusion. The primary objective was development of the stepwise procedure and gauging its technical success, defined by autograft perfusion by direct visual inspection and indigo-cyanine green (ICG) fluorescence. Secondary objectives included intraoperative parameters (operative times, warm ischemia time, and EBL). IACUC (21277) and IRB (HS-21-00162) approval were obtained. The IDEAL Reporting Guidelines were followed. Results: VCBA procurement and autotransplantation was performed in 3 pigs, 2 pulsatile-perfused cadavers, and 1 brain-dead, heart-beating deceased donor (Table 1). Technical success was achieved in two porcine, one cadaveric, and the brain dead deceased donor cases. Operative times in the porcine models ranged from 143-343 min, improving sequentially with each case. A similar finding was noted in the cadaveric model. In the brain-dead heart beating donor, the surgery was well tolerated, with intra-operative hemodynamic stability. Operative time was 670 min. Visual inspection revealed a pink, healthy bladder and patent vascular anastomoses, with diffuse ICG uptake. Conclusions: Porcine and cadaveric models were used to develop a protocol for VCBA procurement and transplantation. This protocol was applied to the first brain-dead heart-beating donor, documenting technically feasibility. The robotic approach facilitates the fine vascular dissection in the deep pelvis. The above cases are necessary preclinical steps towards a first-in-human trial of bladder transplantation. SOURCE OF Funding: This study has been supported by a clinical research grant from the OneLegacy Foundation.
