Robotic infant surgery with 3 mm instruments: a study in piglets of less than 10 kg body weight

Abstract

No data exist concerning the appication of a new robotic system with 3 mm instruments (Senhance®, Transenterix) in infants and small children. Therefore, the aim of this study was to test the system for its feasibility, performance and safety of robotic pediatric abdominal and thoracic surgery in piglets simulating infants with a body weight lower than 10 kg. 34 procedures (from explorative laparoscopy to thoracoscopic esophageal repair) were performed in 12 piglets with a median age of 23 (interquartile range: 12-28) days and a median body weight of 6.9 (6.1-7.3) kg. The Senhance® robotic system was used with 3 mm instruments, a 10 mm 3D 0° or 30° videoscope and advanced energy devices, the setup consisted of the master console and three separate arms. The amount, size, and position of the applied ports, their distance as well as the distance between the three operator arms of the robot, external and internal collisions, and complications of the procedures were recorded and analyzed. We were able to perform all planned surgical procedures with 3 mm robotic instruments in piglets with a median body weight of less than 7 kg. We encountered two non-robot associated complications (bleeding from the inferior caval and hepatic vein) which led to termination of the live procedures. Technical limitations were the reaction time and speed of robotic camera movement with eye tracking, the excessive bending of the 3 mm instruments and intermittent need of re-calibration of the fulcrum point. Robotic newborn and infant surgery appears technically feasible with the Senhance® system. Software adjustments for camera movement and sensitivity of the fulcrum point calibration algorithm to adjust for the increased compliance of the abdominal wall of infants, therefore reducing the bending of the instruments, need to be implemented by the manufacturer as a result of our study. To further evaluate the Senhance® system, prospective trials comparing it to open, laparoscopic and other robotic systems are needed.

Keywords: Minimally invasive surgery; Pediatric surgery; Robotic surgery; Robotics.

Fig. 1

Setup of the experiments. The Senhance can be seen with its three arms, operating a 10 mm camera and a 3 mm instrument in the right and left hand arm. An accessory video screen for the 2D display of the operating field is on the left side. In the background, the Draeger Primus is positioned for anesthesia

Fig. 2

Cholecysto-enterostomy: this figure displays the small workspace the anastomosis was created in. To the left, the tip of a 3 mm Maryland grasper and to the right, a 5 mm needledriver can be seen, demonstrating the confined space in comparison to the instruments created by the fan retractor seen above. The anastomosis could be fashioned with interrupted Vicryl 5–0 TF-1 sutures

Fig. 3

Esophageal reconstruction: this figure shows a 3 mm Maryland grasper and 3 mm scissors with a completed esophageal anastomosis (Vicryl 5–0 TF-1) in between