Robotic Assisted Bronchoscopy

Historical Perspective

The word robot comes from the Czech word “robota” meaning laborer. In 1921, the term robot was rst introduced by Karel Capek in his play Rossom’s Universal Robots. He described the creation and evolution of robots and eventually their revolt against humans. In 1942, writer Isaac Asimov de ned the three rules of robotics in his science ction books “Runaround” and “I, Robot”: robots must not harm humans, must follow instructions, and protect their existence [1].

Before the term “robot” came to life, autonomously operated machines could be dated to 400 BC when Archytas developed a steam-­ powered, self-propelling wooden pigeon capable of fying 200 meters [2]. However, Leonardo da Vinci in 1495 designed the “Metal-Plated Warrior”, the rst robot that imitated human movements of the jaw, arms, and neck (Fig. 26.1). This invention inspired Gianello Torriano, who created a robotic mandolin-play- ing lady in 1540 [1].

It was not until 1985 that robotics entered theeld of medicine. Robot-assisted surgeries have

T. Dammad (*)

AdventHealth Orlando, Orlando, FL, USA

Houston Methodist, Houston, TX, USA

B. A. Jalil

Heart and Vascular Institute, West Virginia University,

Morgantown, WV, USA

been an ongoing development in the last ve decades. The rst robot to be used in surgical procedures was the PUMA 560, introduced in 1985 and assisted in performing computed tomography (CT)-guided biopsies of the brain. Almost a decade after the introduction of the PUMA 560, an endoscopic surgical robot called theAESOP (Automated Endoscopic System for Optimal Positioning) was developed. A decade after introducing the AESOP, Intuitive Surgical, in 1997, introduced the Da Vinci Surgery System for laparoscopic surgery, where the rst laparoscopic cholecystectomy was performed in Belgium [3]. The Da Vinci system has seen an immense expansion in its utility from general surgery, gynecologic surgery, and cardiac and thoracic surgical procedures.

The limitations in conventional bronchoscopy led the path of innovations over the years to attempt tissue sampling in peripheral airways, beyond the visualization of a bronchoscope. One of these innovations is electromagnetic navigational bronchoscopy (ENB), which is the most common modality used to approach peripheral nodules that are beyond the visualization of the subsegmental anatomy and relies on using a combination of a virtual map of the tracheobronchial tree generated from reconstructed CT images and electromagnetically-mapped images to navigate more peripheral airways and lesions. The other modality is radial-endobronchial ultrasound (R-EBUS) which allows for sonographic visualization of peripheral lung lesions combined with

guidance sheath, with or without fuoroscopy or ENB. Although prior data suggested diagnostic yields as high as 70%, more recent data suggests the diagnostic yield to be inconsistent and closer to 40–60% [4–6]. There are a multitude of technical concerns with the stability and extension beyond the bronchoscope during sampling of peripheral lung tissue, which may explain the lower diagnostic yield. Robotic-assisted bronchoscopy (RAB) is an attempt to improve on the problems experienced during ENB.

The rst robotic-assisted bronchoscopy (RAB) platform is the Monarch (Auris Health), utilizing electromagnetic (EM) Guidance that attained Food and Drug Administration (FDA) approval in March 2018. In February 2019, the FDA approved a second RAB platform, the Ion Robotic Endoluminal platform (Intuitive Surgical), utilizing Shape Sensing Technology. Both platforms comprise similar equipment, including a bronchoscope, a robotic interface, and a controller; however, they have a few operational differences.

Description andDesign

The Monarch Platform (Auris Health,

Inc. Redwood City, CA)

The Monarch RAB platform (Fig. 26.2) consists of four main components: The bronchoscope, cart (robotic arms), tower, and the electromagnetic generator.

The bronchoscope (Fig. 26.3a–c) consists of an inner bronchoscope with an outside diameter of 4.2 mm, a working channel of 2.1 mm, a camera, and an integrated light source that enable direct visualization during the procedure. The outer sheath has a 6 mm outer diameter.

The inner bronchoscope is made to telescope through the outer sheath, and its movement can be coupled or uncoupled when advanced in the bronchial tree. Usually, their movement is un-­ coupled past the three-fourth generation of the bronchial tree. The outer sheath and inner bronchoscope both offer four-way steering control

and articulate up to 180 degrees. This con guration enhances the stability of the bronchoscope and maneuverability of the scope to access lesions further into the lung. The proximal end of the bronchoscope (Fig. 26.3d) is equipped with a valve that accesses the 2.1 mm working channel and enables irrigation, suction, and the insertion of various ancillary tools, such as radial ultrasound probe, needle, brush, or biopsy forceps.

The cart (Fig. 26.4) comprises two robotic arms with rotary pulleys (Fig. 26.5) that connect to the bronchoscope cables and exert proper tension to drive the inner bronchoscope and the outer sheath in coupled or uncoupled modes. The bronchoscopist uses a video game-type controller to move the robotic arms to drive and navigate the bronchoscope. The cart contains the electronic systems required to operate the platform and adjust its height and level the robotic arms and the bronchoscope with the entry point of the outer tip of the endotracheal tube.

The tower (Fig. 26.6) connects to the bronchoscope, controller, and the electromagnetic gener-

ator. The controller (Fig. 26.7), with its two joysticks and other control buttons, is used to drive, articulate the bronchoscope, and navigate the screen of the tower to reach the target lesion. The tower has two computers that operate the system, a non-real-time computer and a real-time computer that communicate with each other during the procedure. The non-real-time computer receives input from the pendant, keyboard, mouse, camera, electromagnetic localizer, and power distribution unit. It also contains an interface to the camera at the bronchoscope’s tip that performs the necessary image processing and generates video output streams. On the other hand, the real-time computer receives inputs from the non-real-time computer. Real-time video captured from the bronchoscope’s tip and overlaid with other information from the robotic system is displayed on the tower monitor.

The electromagnetic eld generator is placed close to the patient’s chest with the attached reference electromagnetic sensors, and it is an essential tool for navigation guidance [7].

Procedure andTechnique

Pre-procedure planning is essential for the success of the procedure. It starts with thin-cut chest computed tomography images with a slice thickness of 0.5–1 mm and slice interval of 0.5–0.8 mm.

Three-dimensional virtual lung reconstruction is generated via the software. The target lesion is marked and sized. Then, the robotic system software generates and maps the pathway. Manual planning or segmentation of the airway is possible, especially in the absence of a bronchus sign. The computed tomography scan should preferably be done within 27 days of the procedure.

Metallic objects should be removed from the immediate EM eld during the setup, ­registration, and electromagnetic navigation part of the procedure in the case of the Monarch Robotic System to prevent signal interference. There is no need to this when using the Ion Endoluminal Robotic system.

After consent is obtained and time-out is done, the patient undergoes general anesthesia by the anesthesia team. Paralytics are not mandatory but deep sedation is important. Patient is usually intubated with an endotracheal tube no smaller than 7.5 mm. A tidal volume of 8 mL/kg of predicted body weight and positive end expiratory pressure

(PEEP) of 8 to 10 cmH2O is recommended to prevent atelectasis in the anesthetized patients.

Conventional fexible bronchoscopy is rst done with a fexible bronchoscope to inspect the tracheobronchial tree thoroughly and identify other abnormalities in addition to clearing secretions. Once completed, the fexible bronchoscope is removed and the robotic bronchoscope is advanced to the patient’s airways. Next, registration is done to couple virtual anatomy with the patient’s real-time airway anatomy. The bronchoscopist thereafter navigates to the target lesion.

In the case of the Monarch Robotic Bronchoscope, the outer sheath and the inner bronchoscope are advanced in coupled mode. Once the segmental airway is reached or around the 3-4th bronchial generation, the outer sheath is locked in place, and the inner bronchoscope is uncoupled and advanced further to navigate to the target lesion. The Monarch platform preserves real-time white light vision, while ancillary tools are utilized at the target lesion (Fig. 26.10).

On the other hand, the robotic catheter of the Ion Endoluminal System with the bronchoscope will reach the target lesion, and it will be locked in position; at that point, the vision probe must be removed