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

Abstract

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.

Robotic transanal minimally invasive surgery (r-TAMIS): perioperative and short-term outcomes for local excision of rectal cancers

“…Kajmolli et al compared the Si and Xi platforms reporting three main technical differences: (a) the Si vertically-mounted arms design require the patient to be positioned in an uncomfortable position with asymmetrical hip flexion as opposed to the Xi boom-mounted horizontal arm design, (b) the Si patient cart arms are more bulky compared to the Xi (28 cm vs 19 cm in circumference) which decreases manoeuvrability between patient’s legs, and (c) the abduction pattern of movement of the Si arms could potentially increase the risk of external collision with the patient's legs as opposed to the Xi jack-knife pattern of movement [ 42 ].…”