Robotic TAMIS: A Technical Note Comparing Si® versus Xi®.

Transanal minimally invasive surgery (TAMIS) can be performed robotically assisted (R-TAMIS) for easier rectal defect suture closure particularly on the anterior rectal wall. The surgical technique described in this technical note emphasizes three safety points: 1) decreased likelihood for rectal injury when the ports are inserted into the GelPOINT® Path Transanal Access Platform (Applied Medical, Rancho Santa Margarita, California) on the back table rather than being inserted into the rectum; 2) decreased external collision between ports when using ports of different length; and 3) increased stabilization of pneumorectum when insufflating with an AirSeal™ port (Intelligent Flow System, ConMed, Utica, New York). Although R-TAMIS can be safely performed with the da Vinci® Si® or Xi® (Intuitive Surgical Inc., Sunnyvale, California) patient cart, the following differences are noteworthy: a) the Si® vertically-mounted arms design forces the patient in an uncomfortable position with asymmetrical hip flexion as opposed to the Xi® boom-mounted horizontal arm design; b) the 28cm circumference of each Si® patient cart arms operating between the patient's legs offer decreased maneuvering freedom as opposed to the 19cm circumference of the Xi® counterparts; and c) the abduction pattern of movement of the Si® arms potentially increases the risk of external collision with the patient's legs as opposed to the Xi® "jack-knife" pattern of movement.