Innovations in robotic technology are transforming the way surgeons operate in the 21st century. Robotic surgical platforms grant surgeons access to modern-world defining robotic engineering and computer programming, which enhance the surgeon’s operative view and augment his or her manual dexterity.^1-3 These surgical tools were developed with the goal of helping surgeons overcome the limitations of laparoscopy and to facilitate the broader adaptation of minimally invasive surgery to include more complex abdominal procedures.^4-8 The technologic superiority of robotic surgical platforms over existing open and laparoscopic instruments is undisputed, with the potential to harvest significant advantages for the surgeon and, ultimately, translate them for improved patient outcomes.

As with all new technology, however, robotic surgery poses novel challenges for general surgeons as we begin to define its role in our clinical practices, discern its optimal application for our patients, and determine its benefits and disadvantages.^9-11 Familiarity with robotic surgical systems, the current uses, its optimum utilization, and potential future applications can facilitate the employment of the robotic surgical platforms for gastrointestinal procedures. In this chapter, we will cover the development of the robotic surgical technology and the inherent advantages of the da Vinci Surgical Systems (Intuitive Surgical, Sunnyvale, CA). The chapter will explore how surgeons can exploit specific technologic innovations of the da Vinci robotic surgical platforms in robotic Heller myotomy with fundoplication, radical gastrectomy with lymphadenectomy, and robotic colorectal resections with total mesorectal excision. We will review the results of existing studies focusing on the clinical outcomes of these select robotic gastrointestinal surgeries alone and in comparison to open and laparoscopic approaches. Finally, the chapter will highlight a few distinct features of robotic surgery and possible future applications.

Development of Robotic Surgical Technology

Robotic surgery is the utilization of specifically designed robotic surgical platforms to perform minimally invasive surgical procedures. The foundation of the robotic surgical technology is derived from the innovations of a military project endorsed by the National Aeronautics and Space Administration (NASA). The Defense Advanced Research Project Administration (DARPA) funded the research project in the 1970s.^3,12 At the time, the aim of the surgical robotics project was to enable telesurgery—to create a robot that could be manipulated to care for astronauts in space aircrafts and soldiers in the battlefield without the physical presence of a surgeon alongside the patient. In 2002, the first robot-assisted telesurgery on a human, a cholecystectomy, was performed using the ZEUS system (Computer Motion, Goleta, CA).¹³ The surgeon, Dr. Jacques Marescaux, was seated at the “surgeon-side” subsystems located in New York City with a “patient-side” robot with the patient in Strasbourg, France.

Although the Zeus Robotic Surgical System is no longer used, several companies continued to develop surgical robotics; and currently, all robotic gastrointestinal operations are performed with the da Vinci Surgical Systems.^14-17 They are the only robotic platforms available for abdominal surgery in the adult and pediatric populations. Since the Food and Drug Administration approved Intuitive Surgical’s da Vinci S System in the year 2000, 3 generations of da Vinci Surgical Systems, each with increasingly more sophisticated features, have been developed: the S System (2003), the Si System (2009), and the Xi System (2014).

da Vinci Surgical Systems

The da Vinci Surgical Systems are composed of the surgeon console and the patient-side cart. Similar to laparoscopic surgery, trocars are used as smaller incisional points of entry into the peritoneal cavity. The trocars and the surgical instruments, including the camera, are then attached to robotic arms, which are a part of the patient-side cart. Unlike both open and laparoscopic operations, the primary surgeon is not at the patient’s side but controls the operation from a distance. The surgeon operates seated at the console controlling the instruments attached to the patient-side cart (Fig. 8-1).

Once seated at the console with the head rested on the viewing piece, the surgeon gains complete control of the robot arms with the ability to manipulate the 4 inserted instruments. Bilateral hand and foot controls require the surgeon to coordinate both hand and feet movements throughout the robotic procedure to manipulate the camera position, focus, distance, and angle along with 3 other instruments. A surgeon, resident, or a physician’s assistant with varying degrees of training, experience, and robotic and laparoscopic expertise should assist the primary surgeon at the patient bedside to exchange the instruments, clean the camera lens, help suction, and create exposure of the operative field when necessary during the procedure (Fig. 8-2). The more complex the operation and the less experienced the primary surgeon, the more experienced the bedside assistant should be.

Enhanced Robotic Features

The robotic surgical platforms possess several key innovations (Table 8-1).^5,12 Predominantly, the advancements of robotic surgical platforms over the conventional laparoscopic instruments are its uniquely engineered attributes. These robotic features include the 3-dimensional (3D) high-definition camera with up to 10× magnification of the surgical anatomy. The surgeon has complete control of the camera for timely adjustments of the operative view either during a pause or simultaneously with active maneuvering of 2 other robotic arms. In addition, the scaling of motion and filtering of the surgeon’s tremor allow for increased precision and accuracy of movements unaffected by the fulcrum effect or human fatigue.

The EndoWrist (Intuitive Surgical) function providing 7 degrees of articulation is another significant technologic improvement of robotic surgery over the existing laparoscopic instruments. The ability to articulate beyond the human wrist, which only has 3 degrees of freedom during cutting, sealing, and dissecting, exists in all robotic instruments except in the robotic camera, the Harmonic Ultrasound Shears, and the stapler. Moreover, the surgeon has control of 4 arms of the robotic platform.

Several additional robotic features are available to aide in intraoperative decision making. Tilepro (Intuitive Surgical) is a multidisplay imaging program that allows for simultaneous viewing of other images (intraoperative ultrasound and endoscopies and preoperative radiologic images) that can be activated any time during the operation. In addition, the robotic camera has near-infrared optical capabilities, which allow the surgeon to see fluorescent light for delineation of surgical anatomy including lymph nodes, lymphatic drainage, blood vessels, and the entire biliary tree.

While the initial robotic system was intended for cardiac surgical procedures, the use of the robotic surgical platforms has been used in most surgical subspecialties including urologic, gynecologic, thoracic, vascular, transplant, and general surgeries. In addition, until recently, the field of robotic surgery was dominated by robotic prostatectomies and benign and malignant gynecologic procedures.^18-22 However, with the availability of additional features and greater number of instruments better suited for general surgery on each new robotic surgical platform (Si System and the Xi System), general surgeons are performing numerous complex robotic operations.^23-27

Surgeons in the United States and around the world have performed a wide range of general surgical procedures with robotic assistance (Table 8-2). The robotic general surgical procedures reported to treat diseases in the foregut include Heller myotomies, hiatal hernias, antireflux surgeries (eg, Nissen fundoplication, partial fundoplications), bariatric surgery (eg, Roux-en-Y gastric bypass, sleeves), splenectomies, gastrectomies (eg, radical subtotal distal, total, or proximal gastrectomies), and lymph node dissections. For hindgut diseases, surgeons have used robotic assistance in performing simple right and left colectomies and more complex rectal resections (low anterior resection and abdominoperineal resections) with total mesorectal excisions.

Combined operations, such as colectomies with hepatectomies for metastatic colon cancer and gastrectomies with cholecystectomies for biliary disease and obesity or gastric cancer, have also been reported. Experienced surgeons are performing an increasing number of other more complex hepatopancreaticobiliary operations including liver resections, pancreatic resections (proximal, central, and distal pancreatectomies), and pancreatic resections with venous reconstructions. As pioneering surgeons explore and demonstrate the safety and feasibility of numerous robotic procedures for gastrointestinal diseases, the minimally invasive benefits of robotic surgery as an alternative to laparoscopy are quickly being revealed under critical evaluation.

Rationale for the Robotic Approach

BENEFITS OF MINIMALLY INVASIVE SURGERY

Since the first use of laparoscopy in 1982 for an “endoscopic” appendectomy,²⁸ minimally invasive surgery has earned a prominent place in the armamentarium of general surgeons and has proven its effectiveness in conferring clinical benefit to our patients. For years, pioneering surgeons who used this revolutionary method of operating in the abdomen through small incisions with long stick-like instruments while watching a 2-dimensional view of the operative anatomy experienced significant controversy and criticism regarding its safety, feasibility, increased cost, increased complication rates, and unknown long-term outcomes.²⁹ With increasing surgeon experience, large retrospective studies and well-designed prospective clinical trials have clearly defined the benefits of minimally invasive surgery for patients undergoing abdominal operations for both benign and malignant gastrointestinal diseases.^30-34

The short-term benefits attributed to the decreased trauma of a minimally invasive procedures include shorter hospital stays, less blood loss, decreased pain, earlier return to daily activities, and smaller scars.³⁵ Further support for minimally invasive surgery comes from comparable long-term oncologic outcomes of cancer patients treated with laparoscopic surgery versus open operations.^36-39 The conclusion of the studies is that if surgeons adhere to oncologic principles during laparoscopic surgery as they do through the open approach, patients gain the benefits of the short-term postoperative outcomes without compromising the long-term oncologic outcome.

The laparoscopic approach to abdominal operations to treat certain benign diseases such as cholecystectomy, reflux surgery, and morbid obesity has become standard of care with relatively quick adaptation periods.^40-43 Unfortunately, despite studies to demonstrate improved outcome of minimally invasive surgery, in more complex abdominal operations, the widespread utilization of laparoscopy remains limited. In fact, only 10% of gastric cancer and 15% to 20% of colon cancer operations are performed minimally invasively (laparoscopically) in the United States. The limitations of laparoscopic instrumentation and the steep learning curve of the advanced laparoscopic skills are barriers to widespread use of the laparoscopic approach to complex abdominal operations.^44-48

CHALLENGES OF LAPAROSCOPY

Several formidable impediments to the broader adaptation and greater application of laparoscopy for abdominal operations exist and hinder surgeons from providing the well-accepted benefits of minimally invasive surgery to our patients. Especially for complex gastrointestinal operations, not only is substantial training required to learn the laparoscopic techniques, but also surgeons must gain high-volume experience to master the laparoscopic approach for any specific procedure. This steeper learning curve translates into longer laparoscopic operative times when compared to the open operations. In addition, experienced laparoscopic surgeons have suffered from the long-term detrimental effects of the poor ergonomics of laparoscopic instruments. Robotic surgery offers surgeons access to new technology to overcome these limitations and overcome the disadvantages of laparoscopy.^49,50

ADVANTAGES OF ROBOTIC SURGICAL SYSTEMS

Enhanced robotic features may offer the surgeon several advantages to overcome the difficulty of applying minimally invasive techniques during these complex gastrointestinal procedures. The entire procedure is performed with a 3D view of the operative field, which provides depth perception more closely resembling an open operation as opposed to the 2-dimensional flat view of the laparoscopic screens. More importantly, the 3D view is magnified and can be angled 30 degrees in several directions to see points of the operative field not readily observed during an open operation.

At all points during the operation, the surgeon has control of the camera. This allows the surgeon the ability to manipulate the camera to any position he or she wants at the exact time he or she needs. In addition, when the camera is not being repositioned, it remains steady without any unwanted movements since the robotic arm holding the camera does not fatigue as a human assistant would. This permits a well-coordinated steady 3D magnified operative view throughout the entire surgical procedure.

In fact, the surgeon controls 3 other robotic arms as well. Although only 2 instruments can be manipulated at the same time, a feature to shift control between 2 arms allows the surgeon to position 1 of the arms for retraction and helps improve exposure prior to dissection of a certain area. For example, this feature can be optimized during the suprapancreatic portion of the D2 lymph node dissection during a radical gastrectomy for locally advanced gastric cancer. The third robotic arm holding a Cadiere forceps gently retracts the pancreas in the caudal direction to expose of the celiac axis and splenic artery. The exposure is maintained while the other 2 other arms holding operative instruments carry out that portion of the procedure by dissecting, cutting, burning, ligating, clipping, and providing additional retraction.^51,52

One of the major advantages of the robotic EndoWrist capability is dissection or suturing in narrow operative fields such as working in a male pelvis during robotic total mesorectal excision.^26,53,54 The robotic arms have been found to be facile in the narrow pelvis where open surgery is a challenge and where laparoscopic rectal or perirectal dissection is difficult to perform. Both the EndoWrist instruments and the tremor filter in this area have been noted to be of utility around nerve-sparing procedures of the total mesorectal excision⁵⁵ and during the precise cutting of the esophageal muscles in a Heller myotomy.^56,57 In addition, the Large Needle Driver and the Mega Suture Needle Driver are EndoWristed with 7 degrees of articulation providing natural turning of the suture at many angles, which facilitates quicker and more precise suturing of bowel or vessels during these gastrointestinal operations.

Among the many robotic surgical procedures already performed, the gastrointestinal procedures during which the surgeon can maximize the robotic technology for both the patient and the surgeon benefit can be exemplified in representative operations such as the robotic Heller myotomy with fundoplication, robotic radical gastrectomy with D2 lymphadenectomy, and robot-assisted colorectal resection with total mesorectal excision. As general surgeons continue to gain more experience with the robotic approach, we are affectively harvesting the novel technology afforded by the robotic surgical platforms for the surgeon benefit with the potential to translate them into improved patient outcomes.

In general, surgeons can perform complex operations with increasing ease and precision with the use of the robotic surgical systems over conventional laparoscopy. Current studies of robotic operations for gastrointestinal diseases demonstrate the robotic approach to be safe and feasible and to provide our patients the benefits of minimally invasive surgery with improved outcomes compared to open operations (Table 8-3).^58-60 Moreover, robotic surgeons uniformly report the use of robotic surgical systems to enhance the operative experience and confer an operative advantage during abdominal operations over laparoscopic approaches. Although, robotic surgery has not yet demonstrated any substantial improvement in clinical outcomes when compared to laparoscopy in general, with improved understanding of the superior robotic technology, surgeons have begun to harvest its advantages for specific operations.

Heller Myotomy for Achalasia: Improved Precision During Myotomy

Robotic surgical platform allows for precise dissection of esophageal muscle layers during robotic Heller myotomy, providing an opportunity for surgeons to gain improved surgical outcomes for patients being treated for achalasia. The laparoscopic approach to Heller myotomy has become the standard treatment for achalasia since the minimally invasive approach demonstrated improved outcomes when compared to the open Heller myotomies.^61,62 The esophageal perforation rate for laparoscopic Heller myotomy, however, remains 5% to 10%, leaving room for significant improvement.^63,64 The technically challenging portion of this procedure is the requirement for precise dissection and cutting of the esophageal muscle layers without damage to the underlying esophageal mucosa. Surgeons have achieved a 0% esophageal perforation rate using the robotic surgical platforms.^65-69

The initial report of a successful robotic-assisted Heller myotomy published in 2001 by Melvin et al⁷⁰ has been followed by several series and comparative studies. Talamini et al¹ reported the safety and feasibility of robotic gastrointestinal procedures in 2002 including 5 successfully performed Heller myotomies. In a series of 104 patients undergoing robot-assisted Heller myotomy (RAHM), Melvin et al⁶⁷ reported a 0% esophageal perforation rate with an improvement in the average operative time from 162.63 minutes to 113.50 minutes over a 2-year period. A multi-institutional retrospective study involving 3 institutions comparing 59 RAHM with 62 laparoscopic Heller myotomy patients resulted in similar statistically significant differences in esophageal perforation rates of 0% and 16%, respectively.⁶⁵ This group also found that although the initial robotic operations had longer operative times, the average operative times of the last 30 robotic cases did not differ significantly from the laparoscopic approach. The surgeons attribute the improved outcome to the enhanced robotic visualization of muscular layers and improved control of the robotic instruments.⁶⁹

Robotic Surgery for Gastric Cancer: Shorter Learning Curve for Robotic D2 Lymphadenectomy

Minimally invasive gastric cancer operations provide significantly improved short-term patient outcomes without compromising the long-term effectiveness of properly performed radical gastrectomy with lymphadenectomy when compared to the traditional open surgery.^61-75 Unfortunately, the technical difficulty of performing an extended lymphadenectomy, recommended for all surgically resectable patients with stage II or greater gastric cancer, is well recognized. Even in open radical gastrectomies for gastric cancer, performing D2 lymphadenectomy (removal of all soft tissue containing the lymph nodes that drain the stomach) requires fine dissection around the hepatoduodenal ligament and the celiac axis and along the splenic vessels and is known to have high morbidity and mortality rates in previously published Western studies.^76,77 For laparoscopic approach to this procedure, experienced gastric cancer surgeons report the learning curve plateau to be over 50 cases.^78-81 This is a major challenge because the incidence of gastric cancer in the United States is low, with only a few experienced surgeons able to offer the minimally invasive approach to their gastric cancer patients.⁸²

With the advent of robot-assisted gastric cancer operations, there is a real potential for increasing the percentage of minimally invasive surgeries performed for gastric cancer. The advantages of the robotic surgical platform for gastric cancer operations are several. First, in order to perform a proper minimally invasive D2 lymphadenectomy, the procedure requires 5 ports and 2 skilled assistants, one to drive the camera and other to retract, expose, and suction. With the robotic surgical platform, the surgeon has control of 4 of these 5 arms, providing a steady and readily manipulated camera for the optimum operative view at all times, the ability to create your own retraction, and exposure with the third arm while operating with 2 arms with instruments that have the capacity to articulate around vessels and other tissues.

Second, the robotic camera offers a superior view of the surgical anatomy, and the enhanced dexterity provides the surgeon great assistance during the D2 lymphadenectomy, which requires precise dissection along the pancreas and major vessels including the anterior superior pancreaticoduodenal vein on the head of the pancreas, hepatic artery, portal vein, common hepatic artery, celiac artery, left gastric artery, splenic artery and vein, and at times splenic hilum (lymph node station #10 during total gastrectomies).^83,84 Robotic gastric cancer surgeons have emphasized the importance of these perceived superiorities of the robotic technology in helping them perform better operations.

Robotic surgery for gastric cancer was first reported by Hashizume in Japan (2002)⁸⁵ and then by Giuliantti in the United States (2003)¹⁵ and has since been adopted by many experienced surgeons to perform radical gastrectomies with D2 lymphadenectomies (Table 8-4).^86-90 The single-institution safety and feasibility studies were quickly followed by comparative studies, which demonstrated the robotic surgical advantages of minimally invasive surgery in gastric cancer patients (Table 8-5).^91-100 To date, most of the studies evaluating robotic surgery in the United States include a small number of cases, with the largest study composed of 98 patients who underwent robotic distal (n = 59), total (n = 38), or proximal (n = 1) gastrectomies over a 10-year period by Giulianotti’s group. With an average follow-up of over 3 years, the study demonstrated comparative long-term oncologic outcome to laparoscopic and open operations. The 5-year cumulative survival rates for patients with stage IA, IB, II, and III disease were 100%, 84.6%, 76.9%, and 21.5%, respectively.¹⁰¹