The Smart Tissue Autonomous Robot, known as STAR, in action. A supervised autonomous robot successfully performed soft-tissue surgery. (Sheikh Zayed Institute For Pediatric Innovation)

Having robots perform surgery independently may ultimately improve outcomes for patients, researchers say.

In experiments on pigs, surgical stitches made by autonomous robots were as good as or better than stitches made by skilled surgeons. The same may be true for human patients, according to Peter Kim, the study’s senior author.

“The main message is that by giving surgeons tools that are intelligent, whether autonomous or semi-autonomous, you can make outcomes better,” said Kim, vice president of the Sheikh Zayed Institute for Pediatric Surgical Innovation at Children’s National Health System in Washington.

[Live on June 14 at The Washington Post: Health practitioners and policymakers examine an evolving health care system]

Robotic surgery has become increasingly common, but currently available robots still need to be operated by surgeons’ hands. Autonomous robots would be more consistent than humans, Kim said.

“No matter how steady a surgeon’s hands are, there is always some tremor,” he said.

Using autonomous robots in some of the 44.5 million soft-tissue surgeries in the United States each year might reduce human errors and improve efficiency, surgical time and access to quality surgeons, the researchers wrote recently in the journal Science Translational Medicine.

To see whether robots could complete surgical tasks on their own, the researchers created the Smart Tissue Autonomous Robot (STAR), which consists of a robotic arm, a suturing tool and imaging technologies. The robot uses a computer program informed by best surgical practices to determine where and how to place a stitch.

The researchers first tested STAR’s ability to stitch together two pieces of tissue harvested from pigs. The autonomous robot generally outperformed human surgeons, whether they were using robot-assisted or standard manual techniques. Then the investigators compared the skills of STAR and human surgeons for reconnecting an interrupted intestine in live pigs. The outcomes of the operations by STAR were consistent with the outcomes of a skilled surgeon.

Autonomous robotic surgery still has a long way to go,however.

“It’s something that’s clearly exciting, but we need to see more evidence,” said Keith Lillemoe, chief of surgery at Massachusetts General Hospital, who was not involved in the new study. Lillemoe is not worried about being replaced by a robot, because so many surgical decisions can’t be computerized, he said.

“Surgery is no different than any other field,” Lillemoe said. “Technology can always make us better.”