Robotics Go Where No Surgeon Has Gone Before

The aim of the research is to create a safe, less invasive means of performing coronary bypass surgery, a lifesaving procedure in which blood vessels from the calf or chest are used to route or "bypass" blood around blocked sections of heart arteries. In traditional bypass surgery, the chest cavity is cut open and the bones are "spread," requiring a fairly lengthy and often painful recuperation for patients. The robotics bypass surgery leaves the patient with only a tiny scar, and a much faster and less painful recovery time.

Robotic bypass surgery will likely become available to a select group of heart patients in the near future. However, it will be several years before the technology will be available for large numbers of patients, says Ralph J. Damiano Jr., M.D., professor of surgery and chief of cardiothoracic and vascular surgery at Hershey Medical Center, Penn State University.

Damiano and his colleagues tested the robotic procedure on six men and four women with an average age of 56. In each patient, the robotic operation consisted of freeing a large vessel from the chest wall and sewing it into the left anterior descending coronary artery, the major vessel feeding blood to the left ventricle, the heart's main pumping chamber.

Five additional patients have since been operated on using the robotic system and none have suffered any complications as a result.

"This type of surgery will have a revolutionary impact, not only on heart surgery, but on many types of procedures," Damiano predicts.

"Once the robotic system becomes more cost effective, there is very little reason why you would not want to use it whenever possible. It enhances a physician's dexterity," he says.

"We had no robotic-related complications in any of the patients," says Damiano. "The procedures were done in a reasonable amount of time and all of the vessels were still open six months later," Damiano says. "That is very encouraging." The approach being developed by Damiano and his colleagues is a form of endoscopic surgery that uses a small tubelike instrument. One form, arthroscopy, has been used for joint-replacement surgeries, primarily for the knees, since the 1970s. Another form of endoscopic surgery called laparoscopy is used for abdominal surgeries, such as gallbladder removal. Until recently, however, researchers have not been able to use the endoscopic technique for open heart surgery.

"Anytime you use a long instrument, which is required for microsurgery, you magnify even the smallest tremor. No one has been able to do an endoscopic coronary bypass by hand, although researchers have attempted it in animals for the last five or six years with little success," says Damiano. Another problem is that in traditional endoscopic surgery, someone must hold the camera-light assembly. "That's fine for looking at a wide field, but if you focus in on a small area, even a slight motion by the person holding the light will be distracting," Damiano says.

"The key findings in our study are that robotic bypass is safe and that it appears that this technology should let us perform coronary bypass surgery without a major incision," Damiano says. "We are trying to minimize the surgery by using three pencil-size holes in the chest wall. That alone would offer a major benefit in terms of reduced pain and faster recovery time, which would allow patients to return to their jobs more quickly."

Because their research was a Phase I clinical trial -- a preliminary study aimed at showing the operation is safe -- the U.S. Food and Drug Administration allowed the Penn State team to operate on only one clogged artery in each bypass patient using its robotic system. The other vessels were treated by the traditional method. The heart surgery patients in the study had anywhere from one to four heart arteries that were blocked by a buildup of cholesterol deposits. Over time, the deposits can totally block blood flow to the heart, triggering a heart attack.

The robotic surgery required making three small holes in the chest. Endoscopic surgery uses two surgical instruments and a tiny camera-and-light combination, each of which is inserted into the body through a separate incision. The instruments are rigid and may range from 3 to 16 inches in length. In the Penn State procedure, a separate robotic arm holds each of the two instruments and camera-light assembly. The surgeon sits at a console about 10 feet from the operating table. Using handles shaped like those on traditional microsurgical instruments, the surgeon maneuvers them as if operating directly on the patient.

The surgeon's motions are relayed to a computer which digitizes them. The computer uses this information to direct two robotic arms, which are attached to the operating room table. These arms hold the instrument tips that replicate the precise maneuvers of the surgeon. "The computer takes your motion and makes it very, very smooth," Damiano explains. "Then it takes this digitized motion and uses it to drive the robotic arms."

The camera assembly is controlled through the computer by the surgeon's voice. "The camera is much steadier and that improves visualization," he adds. Co-authors are Walter J. Ehrman, M.D.; Harold A. Tabaie, M.D.; Christopher T. Ducko, M.D.; Edward R. Stephenson, Jr., M.D.; and Charles P. Kingsley, M.D.