da Vinci Surgical System

Patient-side components of a da Vinci system, including the effector arms and endoscope.

The da Vinci Surgical System is a robotic surgical system made by the American company Intuitive Surgical. It is designed to facilitate complex surgery using a minimally invasive approach, and is controlled by a surgeon from a console. The system is commonly used for prostatectomies, and increasingly for cardiac valve repair and gynecologic surgical procedures. According to the manufacturer, the da Vinci System is called "da Vinci" in part "because Leonardo da Vinci invented the first robot", as discovered by Mario Taddei. Da Vinci also used anatomical accuracy and three-dimensional details in his works.

Da Vinci robots operate in several thousand hospitals worldwide, with an estimated 200,000 surgeries conducted in 2012, most commonly for hysterectomies and prostate removals. By January 2013, more than 2,000 units had been sold worldwide. The "Si" version of the system costs on average slightly under US$2 million, in addition to several hundred thousand dollars of annual maintenance fees.

Overview

The da Vinci System consists of a surgeon’s console that is typically in the same room as the patient, and a patient-side cart with four interactive robotic arms controlled from the console. Three of the arms are for tools that hold objects, and can also act as scalpels, scissors, bovies, or unipolar or bipolar electrocautery instruments. The fourth arm carries an endoscopic camera with two lenses that gives the surgeon full stereoscopic vision from the console. The surgeon sits at the console and looks through two eye holes at a 3D image of the procedure, while maneuvering the arms with two foot pedals and two hand controllers. The da Vinci System scales, filters and translates the surgeon's hand movements into more precise micro-movements of the instruments, which operate through small incisions in the body.

To perform a surgical procedure, the surgeon must first use the system's weight to judge how hard it should work. Then he/she uses the console’s master controls to maneuver the patient-side cart’s three or four robotic arms (depending on the model). The instruments’ jointed-wrist design exceeds the natural range of motion of the human hand; motion scaling and tremor reduction further interpret and refine the surgeon’s hand movements. The da Vinci System always requires a human operator, and incorporates multiple redundant safety features designed to minimize opportunities for human error when compared with traditional approaches.

The da Vinci System has been designed to improve upon conventional laparoscopy, in which the surgeon operates while standing, using hand-held, long-shafted instruments, which have no wrists. With conventional laparoscopy, the surgeon must look up and away from the instruments, to a nearby 2D video monitor to see an image of the target anatomy. The surgeon must also rely on his/her patient-side assistant to position the camera correctly. In contrast, the da Vinci System’s ergonomic design allows the surgeon to operate from a seated position at the console, with eyes and hands positioned in line with the instruments. To move the instruments or to reposition the camera, the surgeon simply moves his/her hands.

By providing surgeons with superior visualization, enhanced dexterity, greater precision and ergonomic comfort, the da Vinci Surgical System makes it possible for more surgeons to perform minimally invasive procedures involving complex dissection or reconstruction. For the patient, a da Vinci procedure can offer all the potential benefits of a minimally invasive procedure, including less pain, less blood loss and less need for blood transfusions. Moreover, the da Vinci System can enable a shorter hospital stay, a quicker recovery and faster return to normal daily activities.

FDA approval

The Food and Drug Administration (FDA) cleared the da Vinci Surgical System in 2000 for adult and pediatric use in urologic surgical procedures, general laparoscopic surgical procedures, gynecologic laparoscopic surgical procedures, general non-cardiovascular thoracoscopic surgical procedures and thoracoscopically assisted cardiotomy procedures. The FDA also cleared the da Vinci System to be employed with adjunctive mediastinotomy to perform coronary anastomosis during cardiac revascularization.

Representative clinical uses

The da Vinci System has been successfully used in the following procedures:

• Radical prostatectomy, pyeloplasty, cystectomy, nephrectomy and ureteral reimplantation;
• Hysterectomy, myomectomy and sacrocolpopexy;
• Spleen-sparing distal pancreatectomy, cholecystectomy, Nissen fundoplication, Heller myotomy, gastric bypass, donor nephrectomy, adrenalectomy, splenectomy and bowel resection;
• Internal mammary artery a blood vessel mobilization and cardiac tissue ablation;
• Mitral valve repair and endoscopic atrial septal defect closure;
• Mammary to left anterior descending coronary artery anastomosis for cardiac revascularization with adjunctive mediastinotomy;
• Transoral resection of tumors of the upper aerodigestive tract (tonsil, tongue base, larynx) and transaxillary thyroidectomy

Future applications

Although the general term "robotic surgery" is often used to refer to the technology, this term can give the impression that the da Vinci System is performing the surgery autonomously. In contrast, the current da Vinci Surgical System cannot – in any manner – function on its own, as it was not designed as an autonomous system and lacks decision making software. Instead, it relies on a human operator for all input; however, all operations – including vision and motor functions— are performed through remote human-computer interaction, and thus with the appropriate weak AI software, the system could in principle perform partially or completely autonomously. The difficulty with creating an autonomous system of this kind is not trivial; a major obstacle is that surgery per se is not an engineered process – a requirement for weak AI. The current system is designed merely to replicate seamlessly the movement of the surgeon's hands with the tips of micro-instruments, not to make decisions or move without the surgeon’s direct input.

The da Vinci System could also potentially be used to perform truly remote operations via satellite uplink. This was, in fact, the original design objective of the Da Vinci system, though this was abandoned early in development. The possibility of long-distance operations depends on the patient having access to a da Vinci System, but technically the system could allow a doctor in the United States, for example, to perform telesurgery on a patient in Antarctica.

Criticism

Main article: Robotic surgery#Advantages and disadvantages

Critics of robotic surgery say there is a steep learning curve for surgeons who adopt it, and that there has been a lack of credible studies that indicate long-term results are superior to results following traditional laparoscopic surgery. The Da Vinci system uses proprietary software, which cannot be modified by physicians, thereby limiting the freedom to modify the operation system. With a cost of around $2 million, it may also be beyond the financial reach of many institutions.

The manufacturer of the system, Intuitive Surgical, has been criticized for short-cutting FDA approval by a process known as "premarket notification," which claims the product is similar to already approved products. Intuitive has also been accused of providing inadequate training, and encouraging health care providers to reduce the number of supervised procedures required before a doctor is allowed to use the system without supervision. There have also been claims of patient injuries caused by stray electrical currents released from inappropriate parts of the surgical tips used by the system. Intuitive counters that the same type of stray currents can occur in traditional non-robotic laparoscopic procedures. A study published in the Journal of the American Medical Association, as reported by the New York Times, claims that side-effects and blood loss in robotically-performed hysterectomies are no better than those performed by traditional surgery, despite the significantly greater cost of the system. As of 2013, FDA is reportedly investigating problems with the da Vinci robot, including deaths during surgeries that used the device; a number of related lawsuits are also underway.

External links

• Intuitive Surgical